scons - Man Page

SCons acts on the selected targets, whether the requested operation is build, no-exec or clean. Targets are selected as follows:

1. Targets specified on the command line. These may be files, directories, or phony targets defined using the Alias function. Directory targets are scanned by scons for any targets that may be found with a destination in or under that directory. The targets listed on the command line are made available in the COMMAND_LINE_TARGETS list.
2. If no targets are specified on the command line, scons will select those targets specified in the SConscript files via calls to the Default function. These are known as the default targets, and are made available in the DEFAULT_TARGETS list.
3. If no targets are selected by the previous steps, scons selects the current directory for scanning, unless command-line options which affect the directory for target scanning are present (-C, -D, -u, -U). Since targets thus selected were not the result of user instructions, this target list is not made available for direct inspection; use the --debug=explain option if they need to be examined.
4. scons always adds to the selected targets any intermediate targets which are necessary to build the specified ones. For example, if constructing a shared library or dll from C source files, scons will also build the object files which will make up the library.

To ignore the default targets specified through calls to Default and instead build all target files in or below the current directory specify the current directory (.) as a command-line target:

scons .

To build all target files, including any files outside of the current directory, supply a command-line target of the root directory (on POSIX systems):

scons /

or the path name(s) of the volume(s) in which all the targets should be built (on Windows systems):

scons C:\ D:\

A subset of a hierarchical tree may be built by remaining at the project top directory and specifying the subdirectory as the target to build:

scons src/subdir

or by changing directory and invoking scons with the -u option, which traverses up the directory hierarchy until it finds the SConstruct file, and then builds targets relatively to the current subdirectory (see also the related -D and -U options):

cd src/subdir
scons -u .

In all cases, more files may be built than are requested, as scons needs to make sure any dependent files are built.

Specifying "cleanup" targets in SConscript files is usually not necessary. The -c flag removes all selected targets:

scons -c .

to remove all target files in or under the current directory, or:

scons -c build export

to remove target files under build and export.

Additional files or directories to remove can be specified using the Clean function in the SConscript files. Conversely, targets that would normally be removed by the -c invocation can be retained by calling the NoClean function with those targets.

scons supports building multiple targets in parallel via a -j option that takes, as its argument, the number of simultaneous tasks that may be spawned:

scons -j 4

builds four targets in parallel, for example.

The build configuration is described by one or more files, known as SConscript files. There must be at least one file for a valid build (scons will quit if it does not find one). scons by default looks for this file by the name SConstruct in the directory from which you run scons, though if necessary, also looks for alternative file names Sconstruct, sconstruct, SConstruct.py, Sconstruct.py and sconstruct.py in that order. A different file name (which can include a pathname part) may be specified via the -f option. Except for the SConstruct file, these files are not searched for automatically; you add additional configuration files to the build by calling the SConscript function. This allows parts of the build to be conditionally included or excluded at run-time depending on how scons is invoked.

Each SConscript file in a build configuration is invoked independently in a separate context. This provides necessary isolation so that different parts of the build don't accidentally step on each other. You have to be explicit about sharing information, by using the Export function or the exports argument to the SConscript function, as well as the Return function in a called SConscript file, and consume shared information by using the Import function.

The following sections describe the various SCons facilities that can be used in SConscript files. Quick links:

A Construction Environment is the basic means by which you communicate build information to SCons. A new construction environment is created using the Environment function:

env = Environment()

Construction environment attributes called Construction Variables may be set either by specifying them as keyword arguments when the object is created or by assigning them a value after the object is created. These two are nominally equivalent:

env = Environment(FOO='foo')
env['FOO'] = 'foo'

Note that certain settings which affect tool detection are referenced only when the tools are initialized, so you need either to supply them as part of the call to Environment, or defer tool initialization. For example, initializing the Microsoft Visual C++ version you wish to use:

# initializes msvc to v14.1
env = Environment(MSVC_VERSION="14.1")

env = Environment()
# msvc tool was initialized to default, does not reinitialize
env['MSVC_VERSION'] = "14.1"

env = Environment(tools=[])
env['MSVC_VERSION'] = "14.1"
# msvc tool initialization was deferred, so will pick up new value
env.Tool('default')

As a convenience, construction variables may also be set or modified by the parse_flags keyword argument during object creation, which has the effect of the env.MergeFlags method being applied to the argument value after all other processing is completed. This is useful either if the exact content of the flags is unknown (for example, read from a control file) or if the flags need to be distributed to a number of construction variables. env.ParseFlags describes how these arguments are distributed to construction variables.

env = Environment(parse_flags='-Iinclude -DEBUG -lm')

This example adds 'include' to the $CPPPATH construction variable, 'EBUG' to $CPPDEFINES, and 'm' to $LIBS.

An existing construction environment can be duplicated by calling the env.Clone method. Without arguments, it will be a copy with the same settings. Otherwise, env.Clone takes the same arguments as Environment, and uses the arguments to create a modified copy.

SCons provides a special construction environment called the Default Environment. The default environment is used only for global functions, that is, construction activities called without the context of a regular construction environment. See DefaultEnvironment for more information.

By default, a new construction environment is initialized with a set of builder methods and construction variables that are appropriate for the current platform. The optional platform keyword argument may be used to specify that the construction environment should be initialized for a different platform:

env = Environment(platform='cygwin')

Specifying a platform initializes the appropriate construction variables in the environment to use and generate file names with prefixes and suffixes appropriate for that platform.

Note that the win32 platform adds the SystemDrive and SystemRoot variables from the user's external environment to the construction environment's ENV dictionary. This is so that any executed commands that use sockets to connect with other systems will work on Windows systems.

The platform argument may be a string value representing one of the pre-defined platforms (aix, cygwin, darwin, hpux, irix, os2, posix, sunos or win32), or a callable platform object returned by a call to Platform selecting a pre-defined platform, or it may be a user-supplied callable, in which case the Environment method will call it to update the new construction environment:

def my_platform(env):
    env['VAR'] = 'xyzzy'

env = Environment(platform=my_platform)

Note that supplying a non-default platform or custom function for initialization may bypass settings that should happen for the host system and should be used with care. It is most useful in the case where the platform is an alternative for the one that would be auto-detected, such as platform="cygwin" on a system which would otherwise identify as win32.

The optional tools and toolpath keyword arguments affect the way tools available to the environment are initialized. See the section called “Tools” for details.

The optional variables keyword argument allows passing a Variables object which will be used in the initialization of the construction environment See the section called “Command-Line Construction Variables” for details.

SCons has many included tool modules (more properly, tool specification modules) which are used to help initialize the construction environment prior to building, and more can be written to suit a particular purpose, or added from external sources (a repository of contributed tools is available). More information on writing custom tools can be found in the Extending SCons section and specifically Tool Modules.

An SCons tool is only responsible for setup. For example, if an SConscript file declares the need to construct an object file from a C-language source file by calling the Object builder, then a tool module representing an available C compiler needs to have run first, to set up that builder and all the construction variables it needs in the associated construction environment. The tool itself is not called in the process of the build. Tool setup happens when a construction environment is constructed, and in the basic case needs no intervention - platform-specific lists of default tools are used to examine the specific capabilities of that platform and configure the environment, skipping those tools which are not applicable.

If necessary, a specific set of tools to initialize in an environment during creation may be specified using the optional keyword argument tools. tools must be a list, even if there are one (or zero) tools. This is useful to override the defaults, to specify non-default built-in tools, and to cause added tools to be called:

env = Environment(tools=['msvc', 'lex'])

The tools argument overrides the default tool list, it does not add to it, so be sure to include all the tools you need. For example, if you are building a c/c++ program, you must specify a tool for at least a compiler and a linker, as in tools=['clang', 'link'].

If the tools argument is omitted, or if tools includes the reserved name 'default', then SCons will auto-detect usable tools, using the search path from the execution environment (that is, env['ENV']['PATH']) for looking up any external programs, and the platform name in effect to determine the default tools for that platform. Note the contents of PATH from the external environment os.environ is not used. Changing the PATH in the execution environment after the construction environment is constructed will not cause the tools to be re-detected.

Tools can also be directly called by using the Tool method (see below).

SCons supports the following tool specifications out of the box:

386asm

Sets construction variables for the 386ASM assembler for the Phar Lap ETS embedded operating system.

Sets: $AS, $ASCOM, $ASFLAGS, $ASPPCOM, $ASPPFLAGS.

Uses: $CC, $CPPFLAGS, $_CPPDEFFLAGS, $_CPPINCFLAGS.

aixc++

Sets construction variables for the IMB xlc / Visual Age C++ compiler.

Sets: $CXX, $CXXVERSION, $SHCXX, $SHOBJSUFFIX.

aixcc

Sets construction variables for the IBM xlc / Visual Age C compiler.

Sets: $CC, $CCVERSION, $SHCC.

aixf77

Sets construction variables for the IBM Visual Age f77 Fortran compiler.

Sets: $F77, $SHF77.

aixlink

Sets construction variables for the IBM Visual Age linker.

Sets: $LINKFLAGS, $SHLIBSUFFIX, $SHLINKFLAGS.

applelink

Sets construction variables for the Apple linker (similar to the GNU linker).

Sets: $APPLELINK_COMPATIBILITY_VERSION, $APPLELINK_CURRENT_VERSION, $APPLELINK_NO_COMPATIBILITY_VERSION, $APPLELINK_NO_CURRENT_VERSION, $FRAMEWORKPATHPREFIX, $LDMODULECOM, $LDMODULEFLAGS, $LDMODULEPREFIX, $LDMODULESUFFIX, $LINKCOM, $SHLINKCOM, $SHLINKFLAGS, $_APPLELINK_COMPATIBILITY_VERSION, $_APPLELINK_CURRENT_VERSION, $_FRAMEWORKPATH, $_FRAMEWORKS.

Uses: $FRAMEWORKSFLAGS.

ar

Sets construction variables for the ar library archiver.

Sets: $AR, $ARCOM, $ARFLAGS, $LIBPREFIX, $LIBSUFFIX, $RANLIB, $RANLIBCOM, $RANLIBFLAGS.

as

Sets construction variables for the as assembler.

Sets: $AS, $ASCOM, $ASFLAGS, $ASPPCOM, $ASPPFLAGS.

Uses: $CC, $CPPFLAGS, $_CPPDEFFLAGS, $_CPPINCFLAGS.

bcc32

Sets construction variables for the bcc32 compiler.

Sets: $CC, $CCCOM, $CCFLAGS, $CFILESUFFIX, $CFLAGS, $CPPDEFPREFIX, $CPPDEFSUFFIX, $INCPREFIX, $INCSUFFIX, $SHCC, $SHCCCOM, $SHCCFLAGS, $SHCFLAGS, $SHOBJSUFFIX.

Uses: $_CPPDEFFLAGS, $_CPPINCFLAGS.

cc

Sets construction variables for generic POSIX C compilers.

Sets: $CC, $CCCOM, $CCDEPFLAGS, $CCFLAGS, $CFILESUFFIX, $CFLAGS, $CPPDEFPREFIX, $CPPDEFSUFFIX, $FRAMEWORKPATH, $FRAMEWORKS, $INCPREFIX, $INCSUFFIX, $SHCC, $SHCCCOM, $SHCCFLAGS, $SHCFLAGS, $SHOBJSUFFIX.

Uses: $CCCOMSTR, $PLATFORM, $SHCCCOMSTR.

clang

Set construction variables for the Clang C compiler.

Sets: $CC, $CCDEPFLAGS, $CCVERSION, $SHCCFLAGS.

clangxx

Set construction variables for the Clang C++ compiler.

Sets: $CXX, $CXXVERSION, $SHCXXFLAGS, $SHOBJSUFFIX, $STATIC_AND_SHARED_OBJECTS_ARE_THE_SAME.

compilation_db

Sets up CompilationDatabase builder which generates a clang tooling compatible compilation database.

Sets: $COMPILATIONDB_COMSTR, $COMPILATIONDB_PATH_FILTER, $COMPILATIONDB_USE_ABSPATH.

cvf

Sets construction variables for the Compaq Visual Fortran compiler.

Sets: $FORTRAN, $FORTRANCOM, $FORTRANMODDIR, $FORTRANMODDIRPREFIX, $FORTRANMODDIRSUFFIX, $FORTRANPPCOM, $OBJSUFFIX, $SHFORTRANCOM, $SHFORTRANPPCOM.

Uses: $CPPFLAGS, $FORTRANFLAGS, $SHFORTRANFLAGS, $_CPPDEFFLAGS, $_FORTRANINCFLAGS, $_FORTRANMODFLAG.

cXX

Sets construction variables for generic POSIX C++ compilers.

Sets: $CPPDEFPREFIX, $CPPDEFSUFFIX, $CXX, $CXXCOM, $CXXFILESUFFIX, $CXXFLAGS, $INCPREFIX, $INCSUFFIX, $OBJSUFFIX, $SHCXX, $SHCXXCOM, $SHCXXFLAGS, $SHOBJSUFFIX.

Uses: $CXXCOMSTR, $SHCXXCOMSTR.

cyglink

Set construction variables for cygwin linker/loader.

Sets: $IMPLIBPREFIX, $IMPLIBSUFFIX, $LDMODULEVERSIONFLAGS, $LINKFLAGS, $RPATHPREFIX, $RPATHSUFFIX, $SHLIBPREFIX, $SHLIBSUFFIX, $SHLIBVERSIONFLAGS, $SHLINKCOM, $SHLINKFLAGS, $_LDMODULEVERSIONFLAGS, $_SHLIBVERSIONFLAGS.

default

Sets construction variables for a default list of Tool modules. Use default in the tools list to retain the original defaults, since the tools parameter is treated as a literal statement of the tools to be made available in that construction environment, not an addition.

The list of tools selected by default is not static, but is dependent both on the platform and on the software installed on the platform. Some tools will not initialize if an underlying command is not found, and some tools are selected from a list of choices on a first-found basis. The finished tool list can be examined by inspecting the $TOOLS construction variable in the construction environment.

On all platforms, the tools from the following list are selected if their respective conditions are met: filesystem;, wix, lex, yacc, rpcgen, swig, jar, javac, javah, rmic, dvipdf, dvips, gs, tex, latex, pdflatex, pdftex, tar, zip, textfile.

On Linux systems, the default tools list selects (first-found): a C compiler from gcc, intelc, icc, cc; a C++ compiler from g++, intelc, icc, cXX; an assembler from gas, nasm, masm; a linker from gnulink, ilink; a Fortran compiler from gfortran, g77, ifort, ifl, f95, f90, f77; and a static archiver ar. It also selects all found from the list m4 rpm.

On Windows systems, the default tools list selects (first-found): a C compiler from msvc, mingw, gcc, intelc, icl, icc, cc, bcc32; a C++ compiler from msvc, intelc, icc, g++, cXX, bcc32; an assembler from masm, nasm, gas, 386asm; a linker from mslink, gnulink, ilink, linkloc, ilink32; a Fortran compiler from gfortran, g77, ifl, cvf, f95, f90, fortran; and a static archiver from mslib, ar, tlib; It also selects all found from the list msvs, midl.

On MacOS systems, the default tools list selects (first-found): a C compiler from gcc, cc; a C++ compiler from g++, cXX; an assembler as; a linker from applelink, gnulink; a Fortran compiler from gfortran, f95, f90, g77; and a static archiver ar. It also selects all found from the list m4, rpm.

Default lists for other platforms can be found by examining the scons source code (see SCons/Tool/__init__.py).

dmd

Sets construction variables for D language compiler DMD.

Sets: $DC, $DCOM, $DDEBUG, $DDEBUGPREFIX, $DDEBUGSUFFIX, $DFILESUFFIX, $DFLAGPREFIX, $DFLAGS, $DFLAGSUFFIX, $DINCPREFIX, $DINCSUFFIX, $DLIB, $DLIBCOM, $DLIBDIRPREFIX, $DLIBDIRSUFFIX, $DLIBFLAGPREFIX, $DLIBFLAGSUFFIX, $DLIBLINKPREFIX, $DLIBLINKSUFFIX, $DLINK, $DLINKCOM, $DLINKFLAGPREFIX, $DLINKFLAGS, $DLINKFLAGSUFFIX, $DPATH, $DRPATHPREFIX, $DRPATHSUFFIX, $DVERPREFIX, $DVERSIONS, $DVERSUFFIX, $SHDC, $SHDCOM, $SHDLIBVERSIONFLAGS, $SHDLINK, $SHDLINKCOM, $SHDLINKFLAGS.

docbook

This tool tries to make working with Docbook in SCons a little easier. It provides several toolchains for creating different output formats, like HTML or PDF. Contained in the package is a distribution of the Docbook XSL stylesheets as of version 1.76.1. As long as you don't specify your own stylesheets for customization, these official versions are picked as default...which should reduce the inevitable setup hassles for you.

Implicit dependencies to images and XIncludes are detected automatically if you meet the HTML requirements. The additional stylesheet utils/xmldepend.xsl by Paul DuBois is used for this purpose.

Note, that there is no support for XML catalog resolving offered! This tool calls the XSLT processors and PDF renderers with the stylesheets you specified, that's it. The rest lies in your hands and you still have to know what you're doing when resolving names via a catalog.

For activating the tool "docbook", you have to add its name to the Environment constructor, like this

env = Environment(tools=['docbook'])

On its startup, the docbook tool tries to find a required xsltproc processor, and a PDF renderer, e.g. fop. So make sure that these are added to your system's environment PATH and can be called directly without specifying their full path.

For the most basic processing of Docbook to HTML, you need to have installed

• the Python lxml binding to libxml2, or
• a standalone XSLT processor, currently detected are xsltproc, saxon, saxon-xslt and xalan.

Rendering to PDF requires you to have one of the applications fop or xep installed.

Creating a HTML or PDF document is very simple and straightforward. Say

env = Environment(tools=['docbook'])
env.DocbookHtml('manual.html', 'manual.xml')
env.DocbookPdf('manual.pdf', 'manual.xml')

to get both outputs from your XML source manual.xml. As a shortcut, you can give the stem of the filenames alone, like this:

env = Environment(tools=['docbook'])
env.DocbookHtml('manual')
env.DocbookPdf('manual')

and get the same result. Target and source lists are also supported:

env = Environment(tools=['docbook'])
env.DocbookHtml(['manual.html','reference.html'], ['manual.xml','reference.xml'])

or even

env = Environment(tools=['docbook'])
env.DocbookHtml(['manual','reference'])

Important
Whenever you leave out the list of sources, you may not specify a file extension! The Tool uses the given names as file stems, and adds the suffixes for target and source files accordingly.

The rules given above are valid for the Builders DocbookHtml, DocbookPdf, DocbookEpub, DocbookSlidesPdf and DocbookXInclude. For the DocbookMan transformation you can specify a target name, but the actual output names are automatically set from the refname entries in your XML source.

The Builders DocbookHtmlChunked, DocbookHtmlhelp and DocbookSlidesHtml are special, in that:

1. they create a large set of files, where the exact names and their number depend on the content of the source file, and
2. the main target is always named index.html, i.e. the output name for the XSL transformation is not picked up by the stylesheets.

As a result, there is simply no use in specifying a target HTML name. So the basic syntax for these builders is always:

env = Environment(tools=['docbook'])
env.DocbookHtmlhelp('manual')

If you want to use a specific XSL file, you can set the additional xsl parameter to your Builder call as follows:

env.DocbookHtml('other.html', 'manual.xml', xsl='html.xsl')

Since this may get tedious if you always use the same local naming for your customized XSL files, e.g. html.xsl for HTML and pdf.xsl for PDF output, a set of variables for setting the default XSL name is provided. These are:

DOCBOOK_DEFAULT_XSL_HTML
DOCBOOK_DEFAULT_XSL_HTMLCHUNKED
DOCBOOK_DEFAULT_XSL_HTMLHELP
DOCBOOK_DEFAULT_XSL_PDF
DOCBOOK_DEFAULT_XSL_EPUB
DOCBOOK_DEFAULT_XSL_MAN
DOCBOOK_DEFAULT_XSL_SLIDESPDF
DOCBOOK_DEFAULT_XSL_SLIDESHTML

and you can set them when constructing your environment:

env = Environment(
    tools=['docbook'],
    DOCBOOK_DEFAULT_XSL_HTML='html.xsl',
    DOCBOOK_DEFAULT_XSL_PDF='pdf.xsl',
)
env.DocbookHtml('manual')  # now uses html.xsl

Sets: $DOCBOOK_DEFAULT_XSL_EPUB, $DOCBOOK_DEFAULT_XSL_HTML, $DOCBOOK_DEFAULT_XSL_HTMLCHUNKED, $DOCBOOK_DEFAULT_XSL_HTMLHELP, $DOCBOOK_DEFAULT_XSL_MAN, $DOCBOOK_DEFAULT_XSL_PDF, $DOCBOOK_DEFAULT_XSL_SLIDESHTML, $DOCBOOK_DEFAULT_XSL_SLIDESPDF, $DOCBOOK_FOP, $DOCBOOK_FOPCOM, $DOCBOOK_FOPFLAGS, $DOCBOOK_XMLLINT, $DOCBOOK_XMLLINTCOM, $DOCBOOK_XMLLINTFLAGS, $DOCBOOK_XSLTPROC, $DOCBOOK_XSLTPROCCOM, $DOCBOOK_XSLTPROCFLAGS, $DOCBOOK_XSLTPROCPARAMS.

Uses: $DOCBOOK_FOPCOMSTR, $DOCBOOK_XMLLINTCOMSTR, $DOCBOOK_XSLTPROCCOMSTR.

dvi

Attaches the DVI builder to the construction environment.

dvipdf

Sets construction variables for the dvipdf utility.

Sets: $DVIPDF, $DVIPDFCOM, $DVIPDFFLAGS.

Uses: $DVIPDFCOMSTR.

dvips

Sets construction variables for the dvips utility.

Sets: $DVIPS, $DVIPSFLAGS, $PSCOM, $PSPREFIX, $PSSUFFIX.

Uses: $PSCOMSTR.

f03

Set construction variables for generic POSIX Fortran 03 compilers.

Sets: $F03, $F03COM, $F03FLAGS, $F03PPCOM, $SHF03, $SHF03COM, $SHF03FLAGS, $SHF03PPCOM, $_F03INCFLAGS.

Uses: $F03COMSTR, $F03PPCOMSTR, $FORTRANCOMMONFLAGS, $SHF03COMSTR, $SHF03PPCOMSTR.

f08

Set construction variables for generic POSIX Fortran 08 compilers.

Sets: $F08, $F08COM, $F08FLAGS, $F08PPCOM, $SHF08, $SHF08COM, $SHF08FLAGS, $SHF08PPCOM, $_F08INCFLAGS.

Uses: $F08COMSTR, $F08PPCOMSTR, $FORTRANCOMMONFLAGS, $SHF08COMSTR, $SHF08PPCOMSTR.

f77

Set construction variables for generic POSIX Fortran 77 compilers.

Sets: $F77, $F77COM, $F77FILESUFFIXES, $F77FLAGS, $F77PPCOM, $F77PPFILESUFFIXES, $FORTRAN, $FORTRANCOM, $FORTRANFLAGS, $SHF77, $SHF77COM, $SHF77FLAGS, $SHF77PPCOM, $SHFORTRAN, $SHFORTRANCOM, $SHFORTRANFLAGS, $SHFORTRANPPCOM, $_F77INCFLAGS.

Uses: $F77COMSTR, $F77PPCOMSTR, $FORTRANCOMMONFLAGS, $FORTRANCOMSTR, $FORTRANFLAGS, $FORTRANPPCOMSTR, $SHF77COMSTR, $SHF77PPCOMSTR, $SHFORTRANCOMSTR, $SHFORTRANFLAGS, $SHFORTRANPPCOMSTR.

f90

Set construction variables for generic POSIX Fortran 90 compilers.

Sets: $F90, $F90COM, $F90FLAGS, $F90PPCOM, $SHF90, $SHF90COM, $SHF90FLAGS, $SHF90PPCOM, $_F90INCFLAGS.

Uses: $F90COMSTR, $F90PPCOMSTR, $FORTRANCOMMONFLAGS, $SHF90COMSTR, $SHF90PPCOMSTR.

f95

Set construction variables for generic POSIX Fortran 95 compilers.

Sets: $F95, $F95COM, $F95FLAGS, $F95PPCOM, $SHF95, $SHF95COM, $SHF95FLAGS, $SHF95PPCOM, $_F95INCFLAGS.

Uses: $F95COMSTR, $F95PPCOMSTR, $FORTRANCOMMONFLAGS, $SHF95COMSTR, $SHF95PPCOMSTR.

fortran

Set construction variables for generic POSIX Fortran compilers.

Sets: $FORTRAN, $FORTRANCOM, $FORTRANFLAGS, $SHFORTRAN, $SHFORTRANCOM, $SHFORTRANFLAGS, $SHFORTRANPPCOM.

Uses: $CPPFLAGS, $FORTRANCOMSTR, $FORTRANPPCOMSTR, $SHFORTRANCOMSTR, $SHFORTRANPPCOMSTR, $_CPPDEFFLAGS.

g++

Set construction variables for the g++ C++ compiler.

Sets: $CXX, $CXXVERSION, $SHCXXFLAGS, $SHOBJSUFFIX.

g77

Set construction variables for the g77 Fortran compiler.

Sets: $F77, $F77COM, $F77FILESUFFIXES, $F77PPCOM, $F77PPFILESUFFIXES, $FORTRAN, $FORTRANCOM, $FORTRANPPCOM, $SHF77, $SHF77COM, $SHF77FLAGS, $SHF77PPCOM, $SHFORTRAN, $SHFORTRANCOM, $SHFORTRANFLAGS, $SHFORTRANPPCOM.

Uses: $F77FLAGS, $FORTRANCOMMONFLAGS, $FORTRANFLAGS.

gas

Sets construction variables for the gas assembler. Calls the as tool.

Sets: $AS.

gcc

Set construction variables for the gcc C compiler.

Sets: $CC, $CCDEPFLAGS, $CCVERSION, $SHCCFLAGS.

gdc

Sets construction variables for the D language compiler GDC.

Sets: $DC, $DCOM, $DDEBUG, $DDEBUGPREFIX, $DDEBUGSUFFIX, $DFILESUFFIX, $DFLAGPREFIX, $DFLAGS, $DFLAGSUFFIX, $DINCPREFIX, $DINCSUFFIX, $DLIB, $DLIBCOM, $DLIBDIRPREFIX, $DLIBDIRSUFFIX, $DLIBFLAGPREFIX, $DLIBFLAGSUFFIX, $DLIBLINKPREFIX, $DLIBLINKSUFFIX, $DLINK, $DLINKCOM, $DLINKFLAGPREFIX, $DLINKFLAGS, $DLINKFLAGSUFFIX, $DPATH, $DRPATHPREFIX, $DRPATHSUFFIX, $DVERPREFIX, $DVERSIONS, $DVERSUFFIX, $SHDC, $SHDCOM, $SHDLIBVERSIONFLAGS, $SHDLINK, $SHDLINKCOM, $SHDLINKFLAGS.

gettext

A toolset supporting internationalization and localization of software being constructed with SCons. The toolset loads the following tools:

• xgettext - extract internationalized messages from source code to POT file(s).
• msginit - initialize PO files during initial translation of a project.
• msgmerge - update PO files that already contain translated messages,
• msgfmt - compile textual PO files to binary installable MO files.

When you enable gettext, it internally loads all the above-mentioned tools, so you're encouraged to see their individual documentation.

Each of the above tools provides its own builder(s) which may be used to perform particular activities related to software internationalization. You may be however interested in top-level Translate builder.

To use the gettext tools, add the 'gettext' tool to your construction environment:

env = Environment(tools=['default', 'gettext'])

gfortran

Sets construction variables for the GNU Fortran compiler. Calls the fortran Tool module to set variables.

Sets: $F77, $F90, $F95, $FORTRAN, $SHF77, $SHF77FLAGS, $SHF90, $SHF90FLAGS, $SHF95, $SHF95FLAGS, $SHFORTRAN, $SHFORTRANFLAGS.

gnulink

Set construction variables for GNU linker/loader.

Sets: $LDMODULEVERSIONFLAGS, $RPATHPREFIX, $RPATHSUFFIX, $SHLIBVERSIONFLAGS, $SHLINKFLAGS, $_LDMODULESONAME, $_SHLIBSONAME.

gs

This Tool sets the required construction variables for working with the Ghostscript software. It also registers an appropriate Action with the PDF Builder, such that the conversion from PS/EPS to PDF happens automatically for the TeX/LaTeX toolchain. Finally, it adds an explicit Gs Builder for Ghostscript to the environment.

Sets: $GS, $GSCOM, $GSFLAGS.

Uses: $GSCOMSTR.

hpc++

Set construction variables for the compilers aCC on HP/UX systems.

hpcc

Set construction variables for aCC compilers on HP/UX systems. Calls the cXX tool for additional variables.

Sets: $CXX, $CXXVERSION, $SHCXXFLAGS.

hplink

Sets construction variables for the linker on HP/UX systems.

Sets: $LINKFLAGS, $SHLIBSUFFIX, $SHLINKFLAGS.

icc

Sets construction variables for the icc compiler on OS/2 systems.

Sets: $CC, $CCCOM, $CFILESUFFIX, $CPPDEFPREFIX, $CPPDEFSUFFIX, $CXXCOM, $CXXFILESUFFIX, $INCPREFIX, $INCSUFFIX.

Uses: $CCFLAGS, $CFLAGS, $CPPFLAGS, $_CPPDEFFLAGS, $_CPPINCFLAGS.

icl

Sets construction variables for the Intel C/C++ compiler. Calls the intelc Tool module to set its variables.

ifl

Sets construction variables for the Intel Fortran compiler.

Sets: $FORTRAN, $FORTRANCOM, $FORTRANPPCOM, $SHFORTRANCOM, $SHFORTRANPPCOM.

Uses: $CPPFLAGS, $FORTRANFLAGS, $_CPPDEFFLAGS, $_FORTRANINCFLAGS.

ifort

Sets construction variables for newer versions of the Intel Fortran compiler for Linux.

Sets: $F77, $F90, $F95, $FORTRAN, $SHF77, $SHF77FLAGS, $SHF90, $SHF90FLAGS, $SHF95, $SHF95FLAGS, $SHFORTRAN, $SHFORTRANFLAGS.

ilink

Sets construction variables for the ilink linker on OS/2 systems.

Sets: $LIBDIRPREFIX, $LIBDIRSUFFIX, $LIBLINKPREFIX, $LIBLINKSUFFIX, $LINK, $LINKCOM, $LINKFLAGS.

ilink32

Sets construction variables for the Borland ilink32 linker.

Sets: $LIBDIRPREFIX, $LIBDIRSUFFIX, $LIBLINKPREFIX, $LIBLINKSUFFIX, $LINK, $LINKCOM, $LINKFLAGS.

install

Sets construction variables for file and directory installation.

Sets: $INSTALL, $INSTALLSTR.

intelc

Sets construction variables for the Intel C/C++ compiler (Linux and Windows, version 7 and later). Calls the gcc or msvc (on Linux and Windows, respectively) tool to set underlying variables.

Sets: $AR, $CC, $CXX, $INTEL_C_COMPILER_VERSION, $LINK.

jar

Sets construction variables for the jar utility.

Sets: $JAR, $JARCOM, $JARFLAGS, $JARSUFFIX.

Uses: $JARCOMSTR.

javac

Sets construction variables for the javac compiler.

Sets: $JAVABOOTCLASSPATH, $JAVAC, $JAVACCOM, $JAVACFLAGS, $JAVACLASSPATH, $JAVACLASSSUFFIX, $JAVAINCLUDES, $JAVASOURCEPATH, $JAVASUFFIX.

Uses: $JAVACCOMSTR.

javah

Sets construction variables for the javah tool.

Sets: $JAVACLASSSUFFIX, $JAVAH, $JAVAHCOM, $JAVAHFLAGS.

Uses: $JAVACLASSPATH, $JAVAHCOMSTR.

latex

Sets construction variables for the latex utility.

Sets: $LATEX, $LATEXCOM, $LATEXFLAGS.

Uses: $LATEXCOMSTR.

ldc

Sets construction variables for the D language compiler LDC2.

Sets: $DC, $DCOM, $DDEBUG, $DDEBUGPREFIX, $DDEBUGSUFFIX, $DFILESUFFIX, $DFLAGPREFIX, $DFLAGS, $DFLAGSUFFIX, $DINCPREFIX, $DINCSUFFIX, $DLIB, $DLIBCOM, $DLIBDIRPREFIX, $DLIBDIRSUFFIX, $DLIBFLAGPREFIX, $DLIBFLAGSUFFIX, $DLIBLINKPREFIX, $DLIBLINKSUFFIX, $DLINK, $DLINKCOM, $DLINKFLAGPREFIX, $DLINKFLAGS, $DLINKFLAGSUFFIX, $DPATH, $DRPATHPREFIX, $DRPATHSUFFIX, $DVERPREFIX, $DVERSIONS, $DVERSUFFIX, $SHDC, $SHDCOM, $SHDLIBVERSIONFLAGS, $SHDLINK, $SHDLINKCOM, $SHDLINKFLAGS.

lex

Sets construction variables for the lex lexical analyzer.

Sets: $LEX, $LEXCOM, $LEXFLAGS, $LEXUNISTD.

Uses: $LEXCOMSTR, $LEXFLAGS, $LEX_HEADER_FILE, $LEX_TABLES_FILE.

link

Sets construction variables for generic POSIX linkers. This is a "smart" linker tool which selects a compiler to complete the linking based on the types of source files.

Sets: $LDMODULE, $LDMODULECOM, $LDMODULEFLAGS, $LDMODULENOVERSIONSYMLINKS, $LDMODULEPREFIX, $LDMODULESUFFIX, $LDMODULEVERSION, $LDMODULEVERSIONFLAGS, $LIBDIRPREFIX, $LIBDIRSUFFIX, $LIBLINKPREFIX, $LIBLINKSUFFIX, $LINK, $LINKCOM, $LINKFLAGS, $SHLIBSUFFIX, $SHLINK, $SHLINKCOM, $SHLINKFLAGS, $__LDMODULEVERSIONFLAGS, $__SHLIBVERSIONFLAGS.

Uses: $LDMODULECOMSTR, $LINKCOMSTR, $SHLINKCOMSTR.

linkloc

Sets construction variables for the LinkLoc linker for the Phar Lap ETS embedded operating system.

Sets: $LIBDIRPREFIX, $LIBDIRSUFFIX, $LIBLINKPREFIX, $LIBLINKSUFFIX, $LINK, $LINKCOM, $LINKFLAGS, $SHLINK, $SHLINKCOM, $SHLINKFLAGS.

Uses: $LINKCOMSTR, $SHLINKCOMSTR.

m4

Sets construction variables for the m4 macro processor.

Sets: $M4, $M4COM, $M4FLAGS.

Uses: $M4COMSTR.

masm

Sets construction variables for the Microsoft assembler.

Sets: $AS, $ASCOM, $ASFLAGS, $ASPPCOM, $ASPPFLAGS.

Uses: $ASCOMSTR, $ASPPCOMSTR, $CPPFLAGS, $_CPPDEFFLAGS, $_CPPINCFLAGS.

midl

Sets construction variables for the Microsoft IDL compiler.

Sets: $MIDL, $MIDLCOM, $MIDLFLAGS.

Uses: $MIDLCOMSTR.

mingw

Sets construction variables for MinGW (Minimal Gnu on Windows).

Sets: $AS, $CC, $CXX, $LDMODULECOM, $LIBPREFIX, $LIBSUFFIX, $OBJSUFFIX, $RC, $RCCOM, $RCFLAGS, $RCINCFLAGS, $RCINCPREFIX, $RCINCSUFFIX, $SHCCFLAGS, $SHCXXFLAGS, $SHLINKCOM, $SHLINKFLAGS, $SHOBJSUFFIX, $WINDOWSDEFPREFIX, $WINDOWSDEFSUFFIX.

Uses: $RCCOMSTR, $SHLINKCOMSTR.

msgfmt

This tool is a part of the gettext toolset. It provides SCons an interface to the msgfmt(1) command by setting up the MOFiles builder, which generates binary message catalog (MO) files from a textual translation description (PO files).

Sets: $MOSUFFIX, $MSGFMT, $MSGFMTCOM, $MSGFMTCOMSTR, $MSGFMTFLAGS, $POSUFFIX.

Uses: $LINGUAS_FILE.

msginit

This tool is a part of scons gettext toolset. It provides SCons an interface to the msginit(1) program, by setting up the POInit builder, which creates a new PO file, initializing the meta information with values from the construction environment (or options).

Sets: $MSGINIT, $MSGINITCOM, $MSGINITCOMSTR, $MSGINITFLAGS, $POAUTOINIT, $POCREATE_ALIAS, $POSUFFIX, $POTSUFFIX, $_MSGINITLOCALE.

Uses: $LINGUAS_FILE, $POAUTOINIT, $POTDOMAIN.

msgmerge

This tool is a part of scons gettext toolset. It provides SCons an interface to the msgmerge(1) command, by setting up the POUpdate builder, which merges two Uniform style .po files together.

Sets: $MSGMERGE, $MSGMERGECOM, $MSGMERGECOMSTR, $MSGMERGEFLAGS, $POSUFFIX, $POTSUFFIX, $POUPDATE_ALIAS.

Uses: $LINGUAS_FILE, $POAUTOINIT, $POTDOMAIN.

mslib

Sets construction variables for the Microsoft mslib library archiver.

Sets: $AR, $ARCOM, $ARFLAGS, $LIBPREFIX, $LIBSUFFIX.

Uses: $ARCOMSTR.

mslink

Sets construction variables for the Microsoft linker.

Sets: $LDMODULE, $LDMODULECOM, $LDMODULEFLAGS, $LDMODULEPREFIX, $LDMODULESUFFIX, $LIBDIRPREFIX, $LIBDIRSUFFIX, $LIBLINKPREFIX, $LIBLINKSUFFIX, $LINK, $LINKCOM, $LINKFLAGS, $REGSVR, $REGSVRCOM, $REGSVRFLAGS, $SHLINK, $SHLINKCOM, $SHLINKFLAGS, $WINDOWSDEFPREFIX, $WINDOWSDEFSUFFIX, $WINDOWSEXPPREFIX, $WINDOWSEXPSUFFIX, $WINDOWSPROGMANIFESTPREFIX, $WINDOWSPROGMANIFESTSUFFIX, $WINDOWSSHLIBMANIFESTPREFIX, $WINDOWSSHLIBMANIFESTSUFFIX, $WINDOWS_INSERT_DEF.

Uses: $LDMODULECOMSTR, $LINKCOMSTR, $REGSVRCOMSTR, $SHLINKCOMSTR.

mssdk

Sets variables for Microsoft Platform SDK and/or Windows SDK. Note that unlike most other Tool modules, mssdk does not set construction variables, but sets the environment variables in the environment SCons uses to execute the Microsoft toolchain: %INCLUDE%, %LIB%, %LIBPATH% and %PATH%.

Uses: $MSSDK_DIR, $MSSDK_VERSION, $MSVS_VERSION.

msvc

Sets construction variables for the Microsoft Visual C++ compiler.

Sets: $BUILDERS, $CC, $CCCOM, $CCDEPFLAGS, $CCFLAGS, $CCPCHFLAGS, $CCPDBFLAGS, $CFILESUFFIX, $CFLAGS, $CPPDEFPREFIX, $CPPDEFSUFFIX, $CXX, $CXXCOM, $CXXFILESUFFIX, $CXXFLAGS, $INCPREFIX, $INCSUFFIX, $OBJPREFIX, $OBJSUFFIX, $PCHCOM, $PCHPDBFLAGS, $RC, $RCCOM, $RCFLAGS, $SHCC, $SHCCCOM, $SHCCFLAGS, $SHCFLAGS, $SHCXX, $SHCXXCOM, $SHCXXFLAGS, $SHOBJPREFIX, $SHOBJSUFFIX.

Uses: $CCCOMSTR, $CXXCOMSTR, $MSVC_NOTFOUND_POLICY, $MSVC_SCRIPTERROR_POLICY, $MSVC_SCRIPT_ARGS, $MSVC_SDK_VERSION, $MSVC_SPECTRE_LIBS, $MSVC_TOOLSET_VERSION, $MSVC_USE_SCRIPT, $MSVC_USE_SCRIPT_ARGS, $MSVC_USE_SETTINGS, $MSVC_VERSION, $PCH, $PCHSTOP, $PDB, $SHCCCOMSTR, $SHCXXCOMSTR.

msvs

Sets construction variables for Microsoft Visual Studio.

Sets: $MSVSBUILDCOM, $MSVSCLEANCOM, $MSVSENCODING, $MSVSPROJECTCOM, $MSVSREBUILDCOM, $MSVSSCONS, $MSVSSCONSCOM, $MSVSSCONSCRIPT, $MSVSSCONSFLAGS, $MSVSSOLUTIONCOM.

mwcc

Sets construction variables for the Metrowerks CodeWarrior compiler.

Sets: $CC, $CCCOM, $CFILESUFFIX, $CPPDEFPREFIX, $CPPDEFSUFFIX, $CXX, $CXXCOM, $CXXFILESUFFIX, $INCPREFIX, $INCSUFFIX, $MWCW_VERSION, $MWCW_VERSIONS, $SHCC, $SHCCCOM, $SHCCFLAGS, $SHCFLAGS, $SHCXX, $SHCXXCOM, $SHCXXFLAGS.

Uses: $CCCOMSTR, $CXXCOMSTR, $SHCCCOMSTR, $SHCXXCOMSTR.

mwld

Sets construction variables for the Metrowerks CodeWarrior linker.

Sets: $AR, $ARCOM, $LIBDIRPREFIX, $LIBDIRSUFFIX, $LIBLINKPREFIX, $LIBLINKSUFFIX, $LINK, $LINKCOM, $SHLINK, $SHLINKCOM, $SHLINKFLAGS.

nasm

Sets construction variables for the nasm Netwide Assembler.

Sets: $AS, $ASCOM, $ASFLAGS, $ASPPCOM, $ASPPFLAGS.

Uses: $ASCOMSTR, $ASPPCOMSTR.

ninja

Sets up the Ninja builder, which generates a ninja build file, and then optionally runs ninja.

Note
This is an experimental feature. This functionality is subject to change and/or removal without a deprecation cycle.

Sets: $IMPLICIT_COMMAND_DEPENDENCIES, $NINJA_ALIAS_NAME, $NINJA_CMD_ARGS, $NINJA_COMPDB_EXPAND, $NINJA_DEPFILE_PARSE_FORMAT, $NINJA_DIR, $NINJA_DISABLE_AUTO_RUN, $NINJA_ENV_VAR_CACHE, $NINJA_FILE_NAME, $NINJA_FORCE_SCONS_BUILD, $NINJA_GENERATED_SOURCE_ALIAS_NAME, $NINJA_GENERATED_SOURCE_SUFFIXES, $NINJA_MSVC_DEPS_PREFIX, $NINJA_POOL, $NINJA_REGENERATE_DEPS, $NINJA_SCONS_DAEMON_KEEP_ALIVE, $NINJA_SCONS_DAEMON_PORT, $NINJA_SYNTAX, $_NINJA_REGENERATE_DEPS_FUNC.

Uses: $AR, $ARCOM, $ARFLAGS, $CC, $CCCOM, $CCDEPFLAGS, $CCFLAGS, $CXX, $CXXCOM, $ESCAPE, $LINK, $LINKCOM, $PLATFORM, $PRINT_CMD_LINE_FUNC, $PROGSUFFIX, $RANLIB, $RANLIBCOM, $SHCCCOM, $SHCXXCOM, $SHLINK, $SHLINKCOM.

packaging

Sets construction variables for the Package Builder. If this tool is enabled, the --package-type command-line option is also enabled.

pdf

Sets construction variables for the Portable Document Format builder.

Sets: $PDFPREFIX, $PDFSUFFIX.

pdflatex

Sets construction variables for the pdflatex utility.

Sets: $LATEXRETRIES, $PDFLATEX, $PDFLATEXCOM, $PDFLATEXFLAGS.

Uses: $PDFLATEXCOMSTR.

pdftex

Sets construction variables for the pdftex utility.

Sets: $LATEXRETRIES, $PDFLATEX, $PDFLATEXCOM, $PDFLATEXFLAGS, $PDFTEX, $PDFTEXCOM, $PDFTEXFLAGS.

Uses: $PDFLATEXCOMSTR, $PDFTEXCOMSTR.

python

Loads the Python source scanner into the invoking environment. When loaded, the scanner will attempt to find implicit dependencies for any Python source files in the list of sources provided to an Action that uses this environment.

Available since scons 4.0..

qt

Placeholder tool to alert anyone still using qt tools to switch to qt3 or newer tool.

qt3

Sets construction variables for building Qt3 applications.

Note
This tool is only suitable for building targeted to Qt3, which is obsolete (the tool is deprecated since 4.3, and was renamed to qt3 in 4.5.0. ). There are contributed tools for Qt4 and Qt5, see https://github.com/SCons/scons-contrib^[1]. Qt4 has also passed end of life for standard support (in Dec 2015).

Note paths for these construction variables are assembled using the os.path.join method so they will have the appropriate separator at runtime, but are listed here in the various entries only with the '/' separator for simplicity.

In addition, the construction variables $CPPPATH, $LIBPATH and $LIBS may be modified and the variables $PROGEMITTER, $SHLIBEMITTER and $LIBEMITTER are modified. Because the build-performance is affected when using this tool, you have to explicitly specify it at Environment creation:

Environment(tools=['default','qt3'])

The qt3 tool supports the following operations:

Automatic moc file generation from header files. You do not have to specify moc files explicitly, the tool does it for you. However, there are a few preconditions to do so: Your header file must have the same basename as your implementation file and must stay in the same directory. It must have one of the suffixes .h, .hpp, .H, .hxx, .hh. You can turn off automatic moc file generation by setting $QT3_AUTOSCAN to False. See also the corresponding Moc Builder.

Automatic moc file generation from C++ files. As described in the Qt documentation, include the moc file at the end of the C++ file. Note that you have to include the file, which is generated by the transformation ${QT3_MOCCXXPREFIX}<basename>${QT3_MOCCXXSUFFIX}, by default <basename>.mo. A warning is generated after building the moc file if you do not include the correct file. If you are using VariantDir, you may need to specify duplicate=True. You can turn off automatic moc file generation by setting $QT3_AUTOSCAN to False. See also the corresponding Moc Builder.

Automatic handling of .ui files. The implementation files generated from .ui files are handled much the same as yacc or lex files. Each .ui file given as a source of Program, Library or SharedLibrary will generate three files: the declaration file, the implementation file and a moc file. Because there are also generated headers, you may need to specify duplicate=True in calls to VariantDir. See also the corresponding Uic Builder.

Sets: $QT3DIR, $QT3_AUTOSCAN, $QT3_BINPATH, $QT3_CPPPATH, $QT3_LIB, $QT3_LIBPATH, $QT3_MOC, $QT3_MOCCXXPREFIX, $QT3_MOCCXXSUFFIX, $QT3_MOCFROMCXXCOM, $QT3_MOCFROMCXXFLAGS, $QT3_MOCFROMHCOM, $QT3_MOCFROMHFLAGS, $QT3_MOCHPREFIX, $QT3_MOCHSUFFIX, $QT3_UIC, $QT3_UICCOM, $QT3_UICDECLFLAGS, $QT3_UICDECLPREFIX, $QT3_UICDECLSUFFIX, $QT3_UICIMPLFLAGS, $QT3_UICIMPLPREFIX, $QT3_UICIMPLSUFFIX, $QT3_UISUFFIX.

Uses: $QT3DIR.

rmic

Sets construction variables for the rmic utility.

Sets: $JAVACLASSSUFFIX, $RMIC, $RMICCOM, $RMICFLAGS.

Uses: $RMICCOMSTR.

rpcgen

Sets construction variables for building with RPCGEN.

Sets: $RPCGEN, $RPCGENCLIENTFLAGS, $RPCGENFLAGS, $RPCGENHEADERFLAGS, $RPCGENSERVICEFLAGS, $RPCGENXDRFLAGS.

sgiar

Sets construction variables for the SGI library archiver.

Sets: $AR, $ARCOMSTR, $ARFLAGS, $LIBPREFIX, $LIBSUFFIX, $SHLINK, $SHLINKFLAGS.

Uses: $ARCOMSTR, $SHLINKCOMSTR.

sgic++

Sets construction variables for the SGI C++ compiler.

Sets: $CXX, $CXXFLAGS, $SHCXX, $SHOBJSUFFIX.

sgicc

Sets construction variables for the SGI C compiler.

Sets: $CXX, $SHOBJSUFFIX.

sgilink

Sets construction variables for the SGI linker.

Sets: $LINK, $RPATHPREFIX, $RPATHSUFFIX, $SHLINKFLAGS.

sunar

Sets construction variables for the Sun library archiver.

Sets: $AR, $ARCOM, $ARFLAGS, $LIBPREFIX, $LIBSUFFIX.

Uses: $ARCOMSTR.

sunc++

Sets construction variables for the Sun C++ compiler.

Sets: $CXX, $CXXVERSION, $SHCXX, $SHCXXFLAGS, $SHOBJPREFIX, $SHOBJSUFFIX.

suncc

Sets construction variables for the Sun C compiler.

Sets: $CXX, $SHCCFLAGS, $SHOBJPREFIX, $SHOBJSUFFIX.

sunf77

Set construction variables for the Sun f77 Fortran compiler.

Sets: $F77, $FORTRAN, $SHF77, $SHF77FLAGS, $SHFORTRAN, $SHFORTRANFLAGS.

sunf90

Set construction variables for the Sun f90 Fortran compiler.

Sets: $F90, $FORTRAN, $SHF90, $SHF90FLAGS, $SHFORTRAN, $SHFORTRANFLAGS.

sunf95

Set construction variables for the Sun f95 Fortran compiler.

Sets: $F95, $FORTRAN, $SHF95, $SHF95FLAGS, $SHFORTRAN, $SHFORTRANFLAGS.

sunlink

Sets construction variables for the Sun linker.

Sets: $RPATHPREFIX, $RPATHSUFFIX, $SHLINKFLAGS.

swig

Sets construction variables for the SWIG interface compiler.

Sets: $SWIG, $SWIGCFILESUFFIX, $SWIGCOM, $SWIGCXXFILESUFFIX, $SWIGDIRECTORSUFFIX, $SWIGFLAGS, $SWIGINCPREFIX, $SWIGINCSUFFIX, $SWIGPATH, $SWIGVERSION, $_SWIGINCFLAGS.

Uses: $SWIGCOMSTR.

tar

Sets construction variables for the tar archiver.

Sets: $TAR, $TARCOM, $TARFLAGS, $TARSUFFIX.

Uses: $TARCOMSTR.

tex

Sets construction variables for the TeX formatter and typesetter.

Sets: $BIBTEX, $BIBTEXCOM, $BIBTEXFLAGS, $LATEX, $LATEXCOM, $LATEXFLAGS, $MAKEINDEX, $MAKEINDEXCOM, $MAKEINDEXFLAGS, $TEX, $TEXCOM, $TEXFLAGS.

Uses: $BIBTEXCOMSTR, $LATEXCOMSTR, $MAKEINDEXCOMSTR, $TEXCOMSTR.

textfile

Set construction variables for the Textfile and Substfile builders.

Sets: $FILE_ENCODING, $LINESEPARATOR, $SUBSTFILEPREFIX, $SUBSTFILESUFFIX, $TEXTFILEPREFIX, $TEXTFILESUFFIX.

Uses: $SUBST_DICT.

tlib

Sets construction variables for the Borland tlib library archiver.

Sets: $AR, $ARCOM, $ARFLAGS, $LIBPREFIX, $LIBSUFFIX.

Uses: $ARCOMSTR.

xgettext

This tool is a part of the gettext toolset. It provides SCons an interface to the xgettext(1) program, which extracts internationalized messages from source code. The tool sets up the POTUpdate builder to make PO Template files.

Sets: $POTSUFFIX, $POTUPDATE_ALIAS, $XGETTEXTCOM, $XGETTEXTCOMSTR, $XGETTEXTFLAGS, $XGETTEXTFROM, $XGETTEXTFROMPREFIX, $XGETTEXTFROMSUFFIX, $XGETTEXTPATH, $XGETTEXTPATHPREFIX, $XGETTEXTPATHSUFFIX, $_XGETTEXTDOMAIN, $_XGETTEXTFROMFLAGS, $_XGETTEXTPATHFLAGS.

Uses: $POTDOMAIN.

yacc

Sets construction variables for the yacc parser generator.

Sets: $YACC, $YACCCOM, $YACCFLAGS, $YACCHFILESUFFIX, $YACCHXXFILESUFFIX, $YACCVCGFILESUFFIX, $YACC_GRAPH_FILE_SUFFIX.

Uses: $YACCCOMSTR, $YACCFLAGS, $YACC_GRAPH_FILE, $YACC_HEADER_FILE.

zip

Sets construction variables for the zip archiver.

Sets: $ZIP, $ZIPCOM, $ZIPCOMPRESSION, $ZIPFLAGS, $ZIPSUFFIX.

Uses: $ZIPCOMSTR.

You tell SCons what to build by calling Builders, functions which take particular action(s) to produce target(s) of a particular type (conventionally hinted at by the builder name, e.g. Program) from the specified source files. A builder call is a declaration: SCons enters the specified relationship into its internal dependency node graph, and only later makes the decision on whether anything is actually built, since this depends on command-line options, target selection rules, and whether the target(s) are out-of-date with respect to the sources.

SCons provides a number of builders, and you can also write your own (see Builder Objects). Builders are created dynamically at run-time, often (though not always) by tools which determine whether the external dependencies for the builder are satisfied, and which perform the necessary setup (see Tools). Builders are attached to a construction environment as methods. The available builder methods are registered as key-value pairs in the $BUILDERS attribute of the construction environment, so the available builders can be examined. This example displays them for debugging purposes:

env = Environment()
print("Builders:", list(env['BUILDERS']))

Builder methods take two required arguments: target and source. The target and source arguments can be specified either as positional arguments, in which case target comes first, or as keyword arguments, using target= and source=. Although both arguments are nominally required, if there is a single source and the target can be inferred the target argument can be omitted (see below). Builder methods also take a variety of keyword arguments, described below.

Because long lists of file names can lead to a lot of quoting in a builder call, SCons supplies a Split global function and a same-named environment method that splits a single string into a list, using strings of white-space characters as the delimiter (similar to the Python string split method, but succeeds even if the input isn't a string).

The following are equivalent examples of calling the Program builder method:

env.Program('bar', ['bar.c', 'foo.c'])
env.Program('bar', Split('bar.c foo.c'))
env.Program('bar', env.Split('bar.c foo.c'))
env.Program(source=['bar.c', 'foo.c'], target='bar')
env.Program(target='bar', source=Split('bar.c foo.c'))
env.Program(target='bar', source=env.Split('bar.c foo.c'))
env.Program('bar', source='bar.c foo.c'.split())

Sources and targets can be specified as a scalar or as a list, composed of either strings or nodes (more on nodes below). When specifying path strings, Python follows the POSIX pathname convention: if a string begins with the operating system pathname separator (on Windows both the slash and backslash separator are accepted, and any leading drive specifier is ignored for the determination) it is considered an absolute path, otherwise it is a relative path. If the path string contains no separator characters, it is searched for as a file in the current directory. If it contains separator characters, the search follows down from the starting point, which is the top of the directory tree for an absolute path and the current directory for a relative path. The "current directory" in this context is the directory of the SConscript file currently being processed.

SCons also recognizes a third way to specify path strings: if the string begins with the # character it is top-relative - it works like a relative path, but the search follows down from the project top directory rather than from the current directory. The # can optionally be followed by a pathname separator, which is ignored if found in that position. Top-relative paths only work in places where scons will interpret the path (see some examples below). To be used in other contexts the string will need to be converted to a relative or absolute path first.

Examples:

# The comments describing the targets that will be built
# assume these calls are in a SConscript file in the
# a subdirectory named "subdir".

# Builds the program "subdir/foo" from "subdir/foo.c":
env.Program('foo', 'foo.c')

# Builds the program "/tmp/bar" from "subdir/bar.c":
env.Program('/tmp/bar', 'bar.c')

# An initial '#' or '#/' are equivalent; the following
# calls build the programs "foo" and "bar" (in the
# top-level SConstruct directory) from "subdir/foo.c" and
# "subdir/bar.c", respectively:
env.Program('#foo', 'foo.c')
env.Program('#/bar', 'bar.c')

# Builds the program "other/foo" (relative to the top-level
# SConstruct directory) from "subdir/foo.c":
env.Program('#other/foo', 'foo.c')

# This will not work, only SCons interfaces understand '#',
# os.path.exists is pure Python:
if os.path.exists('#inc/foo.h'):
    env.Append(CPPPATH='#inc')

When the target shares the same base name as the source and only the suffix varies, and if the builder method has a suffix defined for the target file type, then the target argument may be omitted completely, and scons will deduce the target file name from the source file name. The following examples all build the executable program bar (on POSIX systems) or bar.exe (on Windows systems) from the bar.c source file:

env.Program(target='bar', source='bar.c')
env.Program('bar', source='bar.c')
env.Program(source='bar.c')
env.Program('bar.c')

The optional srcdir keyword argument specifies that all source file strings that are not absolute paths or top-relative paths shall be interpreted relative to the specified srcdir. The following example will build the build/prog (or build/prog.exe on Windows) program from the files src/f1.c and src/f2.c:

env.Program('build/prog', ['f1.c', 'f2.c'], srcdir='src')

The optional parse_flags keyword argument causes behavior similar to the env.MergeFlags method, where the argument value is broken into individual settings and merged into the appropriate construction variables.

env.Program('hello', 'hello.c', parse_flags='-Iinclude -DEBUG -lm')

This example adds 'include' to the $CPPPATH construction variable, 'EBUG' to $CPPDEFINES, and 'm' to $LIBS.

The optional chdir keyword argument specifies that the Builder's action(s) should be executed after changing directory. If the chdir argument is a path string or a directory Node, scons will change to the specified directory. If the chdir is not a string or Node and evaluates true, then scons will change to the target file's directory.

# scons will change to the "sub" subdirectory
# before executing the "cp" command.
env.Command(
    target='sub/dir/foo.out',
    source='sub/dir/foo.in',
    action="cp dir/foo.in dir/foo.out",
    chdir='sub',
)

# Because chdir is not a string, scons will change to the
# target's directory ("sub/dir") before executing the
# "cp" command.
env.Command('sub/dir/foo.out', 'sub/dir/foo.in', "cp foo.in foo.out", chdir=True)

Note that SCons will not automatically modify its expansion of construction variables like $TARGET and $SOURCE when using the chdir keyword argument--that is, the expanded file names will still be relative to the project top directory, and consequently incorrect relative to the chdir directory. If you use the chdir keyword argument, you will typically need to supply a different command line using expansions like ${TARGET.file} and ${SOURCE.file} to use just the filename portion of the target and source.

Keyword arguments that are not specifically recognized are treated as construction variable overrides, which replace or add those variables on a limited basis. These overrides will only be in effect when building the target of the builder call, and will not affect other parts of the build. For example, if you want to specify some libraries needed by just one program:

env.Program('hello', 'hello.c', LIBS=['gl', 'glut'])

or generate a shared library with a non-standard suffix:

env.SharedLibrary(
    target='word',
    source='word.cpp',
    SHLIBSUFFIX='.ocx',
    LIBSUFFIXES=['.ocx'],
)

Note that both the $SHLIBSUFFIX and $LIBSUFFIXES construction variables must be set if you want scons to search automatically for dependencies on the non-standard library names; see the descriptions of these variables for more information.

Although the builder methods defined by scons are, in fact, methods of a construction environment object, many may also be called without an explicit environment:

Program('hello', 'hello.c')
SharedLibrary('word', 'word.cpp')

If called this way, the builder will internally use the Default Environment that consists of the tools and values that scons has determined are appropriate for the local system.

Builder methods that can be called without an explicit environment (indicated in the listing of builders below without a leading env.) may be called from custom Python modules that you import into an SConscript file by adding the following to the Python module:

from SCons.Script import *

A builder may add additional targets beyond those requested if an attached Emitter chooses to do so (see the section called “Builder Objects” for more information. $PROGEMITTER is an example). For example, the GNU linker takes a command-line argument -Map=mapfile, which causes it to produce a linker map file in addition to the executable file actually being linked. If the Program builder's emitter is configured to add this mapfile if the option is set, then two targets will be returned when you only provided for one.

For this reason, builder methods always return a NodeList, a list-like object whose elements are Nodes. Nodes are the internal representation of build targets or sources (see the section called “Node Objects” for more information). The returned NodeList object can be passed to other builder methods as source(s) or to other SCons functions or methods where a path string would normally be accepted.

For example, to add a specific preprocessor define when compiling one specific object file but not the others:

bar_obj_list = env.StaticObject('bar.c', CPPDEFINES='-DBAR')
env.Program("prog", ['foo.c', bar_obj_list, 'main.c'])

Using a Node as in this example makes for a more portable build by avoiding having to specify a platform-specific object suffix when calling the Program builder method.

The NodeList object is also convenient to pass to the Default function, for the same reason of avoiding a platform-specific name:

tgt = env.Program("prog", ["foo.c", "bar.c", "main.c"])
Default(tgt)

Builder calls will automatically "flatten" lists passed as source and target, so they are free to contain elements which are themselves lists, such as bar_obj_list returned by the StaticObject call. If you need to manipulate a list of lists returned by builders directly in Python code, you can either build a new list by hand:

foo = Object('foo.c')
bar = Object('bar.c')
objects = ['begin.o'] + foo + ['middle.o'] + bar + ['end.o']
for obj in objects:
    print(str(obj))

Or you can use the Flatten function supplied by SCons to create a list containing just the Nodes, which may be more convenient:

foo = Object('foo.c')
bar = Object('bar.c')
objects = Flatten(['begin.o', foo, 'middle.o', bar, 'end.o'])
for obj in objects:
    print(str(obj))

Since builder calls return a list-like object, not an actual Python list, it is not appropriate to use the Python add operator (+ or +=) to append builder results to a Python list. Because the list and the object are different types, Python will not update the original list in place, but will instead create a new NodeList object containing the concatenation of the list elements and the builder results. This will cause problems for any other Python variables in your SCons configuration that still hold on to a reference to the original list. Instead, use the Python list extend method to make sure the list is updated in-place. Example:

object_files = []

# Do NOT use += here:
#    object_files += Object('bar.c')
#
# It will not update the object_files list in place.
#
# Instead, use the list extend method:
object_files.extend(Object('bar.c'))

The path name for a Node's file may be used by passing the Node to Python's built-in str function:

bar_obj_list = env.StaticObject('bar.c', CPPDEFINES='-DBAR')
print("The path to bar_obj is:", str(bar_obj_list[0]))

Note that because the Builder call returns a NodeList, you have to access the first element in the list (bar_obj_list[0] in the example) to get at the Node that actually represents the object file.

When trying to handle errors that may occur in a builder method, consider that the corresponding Action is executed at a different time than the SConscript file statement calling the builder. It is not useful to wrap a builder call in a try block, since success in the builder call is not the same as the builder itself succeeding. If necessary, a Builder's Action should be coded to exit with a useful exception message indicating the problem in the SConscript files - programmatically recovering from build errors is rarely useful.

The following builder methods are predefined in the SCons core software distribution. Depending on the setup of a particular construction environment and on the type and software installation status of the underlying system, not all builders may be available in that construction environment. Since the function calling signature is the same for all builders:

Buildername(target, source, [key=val, ...])

it is omitted in this listing for brevity.

CFile(), env.CFile()

Builds a C source file given a lex (.l) or yacc (.y) input file. The suffix specified by the $CFILESUFFIX construction variable (.c by default) is automatically added to the target if it is not already present. Example:

# builds foo.c
env.CFile(target='foo.c', source='foo.l')

# builds bar.c
env.CFile(target='bar', source='bar.y')

Command(), env.Command()

There is actually no Builder named Command, rather the term "Command Builder" refers to a function which, on each call, creates and calls an anonymous Builder. This is useful for "one-off" builds where a full Builder is not needed. Since the anonymous Builder is never hooked into the standard Builder framework, an Action must always be specified. See the Command function description for the calling syntax and details.

CompilationDatabase(), env.CompilationDatabase()

CompilationDatabase is a special builder which adds a target to create a JSON formatted compilation database compatible with clang tooling (see the LLVM specification^[2]). This database is suitable for consumption by various tools and editors who can use it to obtain build and dependency information which otherwise would be internal to SCons. The builder does not require any source files to be specified, rather it arranges to emit information about all of the C, C++ and assembler source/output pairs identified in the build that are not excluded by the optional filter $COMPILATIONDB_PATH_FILTER. The target is subject to the usual SCons target selection rules.

If called with no arguments, the builder will default to a target name of compile_commands.json.

If called with a single positional argument, scons will "deduce" the target name from that source argument, giving it the same name, and then ignore the source. This is the usual way to call the builder if a non-default target name is wanted.

If called with either the target= or source= keyword arguments, the value of the argument is taken as the target name. If called with both, the target= value is used and source= is ignored. If called with multiple sources, the source list will be ignored, since there is no way to deduce what the intent was; in this case the default target name will be used.

Note
You must load the compilation_db tool prior to specifying any part of your build or some source/output files will not show up in the compilation database.

Available since scons 4.0.

CXXFile(), env.CXXFile()

Builds a C++ source file given a lex (.ll) or yacc (.yy) input file. The suffix specified by the $CXXFILESUFFIX construction variable (.cc by default) is automatically added to the target if it is not already present. Example:

# builds foo.cc
env.CXXFile(target='foo.cc', source='foo.ll')

# builds bar.cc
env.CXXFile(target='bar', source='bar.yy')

DocbookEpub(), env.DocbookEpub()

A pseudo-Builder, providing a Docbook toolchain for EPUB output.

env = Environment(tools=['docbook'])
env.DocbookEpub('manual.epub', 'manual.xml')

or simply

env = Environment(tools=['docbook'])
env.DocbookEpub('manual')

DocbookHtml(), env.DocbookHtml()

A pseudo-Builder, providing a Docbook toolchain for HTML output.

env = Environment(tools=['docbook'])
env.DocbookHtml('manual.html', 'manual.xml')

or simply

env = Environment(tools=['docbook'])
env.DocbookHtml('manual')

DocbookHtmlChunked(), env.DocbookHtmlChunked()

A pseudo-Builder providing a Docbook toolchain for chunked HTML output. It supports the base.dir parameter. The chunkfast.xsl file (requires "EXSLT") is used as the default stylesheet. Basic syntax:

env = Environment(tools=['docbook'])
env.DocbookHtmlChunked('manual')

where manual.xml is the input file.

If you use the root.filename parameter in your own stylesheets you have to specify the new target name. This ensures that the dependencies get correct, especially for the cleanup via “scons -c”:

env = Environment(tools=['docbook'])
env.DocbookHtmlChunked('mymanual.html', 'manual', xsl='htmlchunk.xsl')

Some basic support for the base.dir parameter is provided. You can add the base_dir keyword to your Builder call, and the given prefix gets prepended to all the created filenames:

env = Environment(tools=['docbook'])
env.DocbookHtmlChunked('manual', xsl='htmlchunk.xsl', base_dir='output/')

Make sure that you don't forget the trailing slash for the base folder, else your files get renamed only!

DocbookHtmlhelp(), env.DocbookHtmlhelp()

A pseudo-Builder, providing a Docbook toolchain for HTMLHELP output. Its basic syntax is:

env = Environment(tools=['docbook'])
env.DocbookHtmlhelp('manual')

where manual.xml is the input file.

If you use the root.filename parameter in your own stylesheets you have to specify the new target name. This ensures that the dependencies get correct, especially for the cleanup via “scons -c”:

env = Environment(tools=['docbook'])
env.DocbookHtmlhelp('mymanual.html', 'manual', xsl='htmlhelp.xsl')

Some basic support for the base.dir parameter is provided. You can add the base_dir keyword to your Builder call, and the given prefix gets prepended to all the created filenames:

env = Environment(tools=['docbook'])
env.DocbookHtmlhelp('manual', xsl='htmlhelp.xsl', base_dir='output/')

Make sure that you don't forget the trailing slash for the base folder, else your files get renamed only!

DocbookMan(), env.DocbookMan()

A pseudo-Builder, providing a Docbook toolchain for Man page output. Its basic syntax is:

env = Environment(tools=['docbook'])
env.DocbookMan('manual')

where manual.xml is the input file. Note, that you can specify a target name, but the actual output names are automatically set from the refname entries in your XML source.

DocbookPdf(), env.DocbookPdf()

A pseudo-Builder, providing a Docbook toolchain for PDF output.

env = Environment(tools=['docbook'])
env.DocbookPdf('manual.pdf', 'manual.xml')

or simply

env = Environment(tools=['docbook'])
env.DocbookPdf('manual')

DocbookSlidesHtml(), env.DocbookSlidesHtml()

A pseudo-Builder, providing a Docbook toolchain for HTML slides output.

env = Environment(tools=['docbook'])
env.DocbookSlidesHtml('manual')

If you use the titlefoil.html parameter in your own stylesheets you have to give the new target name. This ensures that the dependencies get correct, especially for the cleanup via “scons -c”:

env = Environment(tools=['docbook'])
env.DocbookSlidesHtml('mymanual.html','manual', xsl='slideshtml.xsl')

Some basic support for the base.dir parameter is provided. You can add the base_dir keyword to your Builder call, and the given prefix gets prepended to all the created filenames:

env = Environment(tools=['docbook'])
env.DocbookSlidesHtml('manual', xsl='slideshtml.xsl', base_dir='output/')

Make sure that you don't forget the trailing slash for the base folder, else your files get renamed only!

DocbookSlidesPdf(), env.DocbookSlidesPdf()

A pseudo-Builder, providing a Docbook toolchain for PDF slides output.

env = Environment(tools=['docbook'])
env.DocbookSlidesPdf('manual.pdf', 'manual.xml')

or simply

env = Environment(tools=['docbook'])
env.DocbookSlidesPdf('manual')

DocbookXInclude(), env.DocbookXInclude()

A pseudo-Builder, for resolving XIncludes in a separate processing step.

env = Environment(tools=['docbook'])
env.DocbookXInclude('manual_xincluded.xml', 'manual.xml')

DocbookXslt(), env.DocbookXslt()

A pseudo-Builder, applying a given XSL transformation to the input file.

env = Environment(tools=['docbook'])
env.DocbookXslt('manual_transformed.xml', 'manual.xml', xsl='transform.xslt')

Note, that this builder requires the xsl parameter to be set.

DVI(), env.DVI()

Builds a .dvi file from a .tex, .ltx or .latex input file. If the source file suffix is .tex, scons will examine the contents of the file; if the string \documentclass or \documentstyle is found, the file is assumed to be a LaTeX file and the target is built by invoking the $LATEXCOM command line; otherwise, the $TEXCOM command line is used. If the file is a LaTeX file, the DVI builder method will also examine the contents of the .aux file and invoke the $BIBTEX command line if the string bibdata is found, start $MAKEINDEX to generate an index if a .ind file is found and will examine the contents .log file and re-run the $LATEXCOM command if the log file says it is necessary.

The suffix .dvi (hard-coded within TeX itself) is automatically added to the target if it is not already present. Examples:

# builds from aaa.tex
env.DVI(target = 'aaa.dvi', source = 'aaa.tex')
# builds bbb.dvi
env.DVI(target = 'bbb', source = 'bbb.ltx')
# builds from ccc.latex
env.DVI(target = 'ccc.dvi', source = 'ccc.latex')

Gs(), env.Gs()

A Builder for explicitly calling the gs executable. Depending on the underlying OS, the different names gs, gsos2 and gswin32c are tried.

env = Environment(tools=['gs'])
env.Gs(
    'cover.jpg',
    'scons-scons.pdf',
    GSFLAGS='-dNOPAUSE -dBATCH -sDEVICE=jpeg -dFirstPage=1 -dLastPage=1 -q',
)

Install(), env.Install()

Installs one or more source files or directories in the specified target, which must be a directory. The names of the specified source files or directories remain the same within the destination directory. The sources may be given as a string or as a node returned by a builder.

env.Install(target='/usr/local/bin', source=['foo', 'bar'])

Note that if target paths chosen for the Install builder (and the related InstallAs and InstallVersionedLib builders) are outside the project tree, such as in the example above, they may not be selected for "building" by default, since in the absence of other instructions scons builds targets that are underneath the top directory (the directory that contains the SConstruct file, usually the current directory). Use command line targets or the Default function in this case.

If the --install-sandbox command line option is given, the target directory will be prefixed by the directory path specified. This is useful to test installation behavior without installing to a "live" location in the system.

See also FindInstalledFiles. For more thoughts on installation, see the User Guide (particularly the section on Command-Line Targets and the chapters on Installing Files and on Alias Targets).

InstallAs(), env.InstallAs()

Installs one or more source files or directories to specific names, allowing changing a file or directory name as part of the installation. It is an error if the target and source arguments list different numbers of files or directories.

env.InstallAs(target='/usr/local/bin/foo',
              source='foo_debug')
env.InstallAs(target=['../lib/libfoo.a', '../lib/libbar.a'],
              source=['libFOO.a', 'libBAR.a'])

See the note under Install.

InstallVersionedLib(), env.InstallVersionedLib()

Installs a versioned shared library. The symlinks appropriate to the architecture will be generated based on symlinks of the source library.

env.InstallVersionedLib(target='/usr/local/bin/foo',
                        source='libxyz.1.5.2.so')

See the note under Install.

Jar(), env.Jar()

Builds a Java archive (.jar) file from the specified list of sources. Any directories in the source list will be searched for .class files). Any .java files in the source list will be compiled to .class files by calling the Java Builder.

If the $JARCHDIR value is set, the jar command will change to the specified directory using the -C option. If $JARCHDIR is not set explicitly, SCons will use the top of any subdirectory tree in which Java .class were built by the Java Builder.

If the contents any of the source files begin with the string Manifest-Version, the file is assumed to be a manifest and is passed to the jar command with the m option set.

env.Jar(target = 'foo.jar', source = 'classes')

env.Jar(target = 'bar.jar',
        source = ['bar1.java', 'bar2.java'])

Java(), env.Java()

Builds one or more Java class files. The sources may be any combination of explicit .java files, or directory trees which will be scanned for .java files.

SCons will parse each source .java file to find the classes (including inner classes) defined within that file, and from that figure out the target .class files that will be created. The class files will be placed underneath the specified target directory.

SCons will also search each Java file for the Java package name, which it assumes can be found on a line beginning with the string package in the first column; the resulting .class files will be placed in a directory reflecting the specified package name. For example, the file Foo.java defining a single public Foo class and containing a package name of sub.dir will generate a corresponding sub/dir/Foo.class class file.

Examples:

env.Java(target='classes', source='src')
env.Java(target='classes', source=['src1', 'src2'])
env.Java(target='classes', source=['File1.java', 'File2.java'])

Java source files can use the native encoding for the underlying OS. Since SCons compiles in simple ASCII mode by default, the compiler will generate warnings about unmappable characters, which may lead to errors as the file is processed further. In this case, the user must specify the LANG environment variable to tell the compiler what encoding is used. For portability, it's best if the encoding is hard-coded, so that the compilation works when run on a system with a different encoding.

env = Environment()
env['ENV']['LANG'] = 'en_GB.UTF-8'

JavaH(), env.JavaH()

Builds C header and source files for implementing Java native methods. The target can be either a directory in which the header files will be written, or a header file name which will contain all of the definitions. The source can be the names of .class files, the names of .java files to be compiled into .class files by calling the Java builder method, or the objects returned from the Java builder method.

If the construction variable $JAVACLASSDIR is set, either in the environment or in the call to the JavaH builder method itself, then the value of the variable will be stripped from the beginning of any .class file names.

Examples:

# builds java_native.h
classes = env.Java(target="classdir", source="src")
env.JavaH(target="java_native.h", source=classes)

# builds include/package_foo.h and include/package_bar.h
env.JavaH(target="include", source=["package/foo.class", "package/bar.class"])

# builds export/foo.h and export/bar.h
env.JavaH(
    target="export",
    source=["classes/foo.class", "classes/bar.class"],
    JAVACLASSDIR="classes",
)

Note
Java versions starting with 10.0 no longer use the javah command for generating JNI headers/sources, and indeed have removed the command entirely (see Java Enhancement Proposal JEP 313^[3]), making this tool harder to use for that purpose. SCons may autodiscover a javah belonging to an older release if there are multiple Java versions on the system, which will lead to incorrect results. To use with a newer Java, override the default values of $JAVAH (to contain the path to the javac) and $JAVAHFLAGS (to contain at least a -h flag) and note that generating headers with javac requires supplying source .java files only, not .class files.

Library(), env.Library()

A synonym for the StaticLibrary builder method.

LoadableModule(), env.LoadableModule()

On most systems, this is the same as SharedLibrary. On Mac OS X (Darwin) platforms, this creates a loadable module bundle.

M4(), env.M4()

Builds an output file from an M4 input file. This uses a default $M4FLAGS value of -E, which considers all warnings to be fatal and stops on the first warning when using the GNU version of m4. Example:

env.M4(target = 'foo.c', source = 'foo.c.m4')

Moc(), env.Moc()

Builds an output file from a moc input file. moc input files are either header files or C++ files. This builder is only available after using the tool qt3. See the $QT3DIR variable for more information. Example:

env.Moc('foo.h')  # generates moc_foo.cc
env.Moc('foo.cpp')  # generates foo.moc

MOFiles(), env.MOFiles()

This builder is set up by the msgfmt tool. The builder compiles PO files to MO files. MOFiles is a single-source builder. The source parameter can also be omitted if $LINGUAS_FILE is set.

Example 1. Create pl.mo and en.mo by compiling pl.po and en.po:

env.MOFiles(['pl', 'en'])

Example 2. Compile files for languages defined in LINGUAS file:

env.MOFiles(LINGUAS_FILE=True)

Example 3. Create pl.mo and en.mo by compiling pl.po and en.po plus files for languages defined in LINGUAS file:

env.MOFiles(['pl', 'en'], LINGUAS_FILE=True)

Example 4. Compile files for languages defined in LINGUAS file (another version):

env['LINGUAS_FILE'] = True
env.MOFiles()

MSVSProject(), env.MSVSProject()

Build a Microsoft Visual C++ project file and solution file.

Builds a Microsoft Visual C++ project file based on the version of Visual Studio (or to be more precise, of MSBuild) that is configured: either the latest installed version, or the version specified by $MSVC_VERSION in the current construction environment. For Visual Studio 6.0 a .dsp file is generated. For Visual Studio versions 2002-2008, a .vcproj file is generated. For Visual Studio 2010 and later a .vcxproj file is generated. Note there are multiple versioning schemes involved in the Microsoft compilation environment - see the description of $MSVC_VERSION for equivalences. Note SCons does not know how to construct project files for other languages (e.g. .csproj for C#, .vbproj for Visual Basic or .pyproject for Python).

For the .vcxproj file, the underlying format is the MSBuild XML Schema, and the details conform to: https://learn.microsoft.com/en-us/cpp/build/reference/vcxproj-file-structure^[4]. The generated solution file enables Visual Studio to understand the project structure, and allows building it using MSBuild to call back to SCons. The project file encodes a toolset version that has been selected by SCons as described above. Since recent Visual Studio versions support multiple concurrent toolsets, use $MSVC_VERSION to select the desired one if it does not match the SCons default. The project file also includes entries which describe how to call SCons to build the project from within Visual Studio (or from an MSBuild command line). In some situations SCons may generate this incorrectly - notably when using the scons-local distribution, which is not installed in a way that that matches the default invocation line. If so, the $SCONS_HOME construction variable can be used to describe the right way to locate the SCons code so that it can be imported.

By default, a matching solution file for the project is also generated. This behavior may be disabled by specifying auto_build_solution=0 to the MSVSProject builder. The solution file can also be independently generated by calling the MSVSSolution builder, such as in the case where a solution should describe multiple projects. See the MSVSSolution description for further information.

The MSVSProject builder accepts several keyword arguments describing lists of filenames to be placed into the project file. Currently, srcs, incs, localincs, resources, and misc are recognized. The names are intended to be self-explanatory, but note that the filenames need to be specified as strings, not as SCons File Nodes (for example if you generate files for inclusion by using the Glob function, the results should be converted to a list of strings before passing them to MSVSProject). This is because Visual Studio and MSBuild know nothing about SCons Node types. Each of the filename lists are individually optional, but at least one list must be specified for the resulting project file to be non-empty.

In addition to the above lists of values, the following values may be specified as keyword arguments:

target

The name of the target .dsp or .vcproj file. The correct suffix for the version of Visual Studio must be used, but the $MSVSPROJECTSUFFIX construction variable will be defined to the correct value (see example below).

variant

The name of this particular variant. Except for Visual Studio 6 projects, this can also be a list of variant names. These are typically things like "Debug" or "Release", but really can be anything you want. For Visual Studio 7 projects, they may also specify a target platform separated from the variant name by a | (vertical pipe) character: Debug|Xbox. The default target platform is Win32. Multiple calls to MSVSProject with different variants are allowed; all variants will be added to the project file with their appropriate build targets and sources.

cmdargs

Additional command line arguments for the different variants. The number of cmdargs entries must match the number of variant entries, or be empty (not specified). If you give only one, it will automatically be propagated to all variants.

cppdefines

Preprocessor definitions for the different variants. The number of cppdefines entries must match the number of variant entries, or be empty (not specified). If you give only one, it will automatically be propagated to all variants. If you don't give this parameter, SCons will use the invoking environment's $CPPDEFINES entry for all variants.

cppflags

Compiler flags for the different variants. If a /std:c++ flag is found then /Zc:__cplusplus is appended to the flags if not already found, this ensures that Intellisense uses the /std:c++ switch. The number of cppflags entries must match the number of variant entries, or be empty (not specified). If you give only one, it will automatically be propagated to all variants. If you don't give this parameter, SCons will combine the invoking environment's $CCFLAGS, $CXXFLAGS, $CPPFLAGS entries for all variants.

cpppaths

Compiler include paths for the different variants. The number of cpppaths entries must match the number of variant entries, or be empty (not specified). If you give only one, it will automatically be propagated to all variants. If you don't give this parameter, SCons will use the invoking environment's $CPPPATH entry for all variants.

buildtarget

An optional string, node, or list of strings or nodes (one per build variant), to tell the Visual Studio debugger what output target to use in what build variant. The number of buildtarget entries must match the number of variant entries.

runfile

The name of the file that Visual Studio 7 and later will run and debug. This appears as the value of the Output field in the resulting Microsoft Visual C++ project file. If this is not specified, the default is the same as the specified buildtarget value.
Note

SCons and Microsoft Visual Studio understand projects in different ways, and the mapping is sometimes imperfect:

Because SCons always executes its build commands from the directory in which the SConstruct file is located, if you generate a project file in a different directory than the directory of the SConstruct file, users will not be able to double-click on the file name in compilation error messages displayed in the Visual Studio console output window. This can be remedied by adding the Microsoft Visual C++ /FC compiler option to the $CCFLAGS variable so that the compiler will print the full path name of any files that cause compilation errors.

If the project file is only used to teach the Visual Studio project browser about the file layout there should be no issues, However, Visual Studio should not be used to make changes to the project structure, build options, etc. as these will (a) not feed back to the SCons description of the project and (b) be lost if SCons regenerates the project file. The SConscript files should remain the definitive description of the build.

If the project file is used to drive MSBuild (such as selecting "build" from the Visual Studio interface) you lose the direct control of target selection and command-line options you would have if launching the build directly from SCons, because these will be hard-coded in the project file to the values specified in the MSVSProject call. You can regain some of this control by defining multiple variants, using multiple MSVSProject calls to arrange different build targets, arguments, defines, flags and paths for different variants.

If the build is divided into a solution with multiple MSBuild projects the mapping is further strained. In this case, it is important not to set Visual Studio to do parallel builds, as it will then launch the separate project builds in parallel, and SCons does not work well if called that way. Instead, you can set up the SCons build for parallel building - see the SetOption function for how to do this with num_jobs.

Example usage:

barsrcs = ['bar.cpp']
barincs = ['bar.h']
barlocalincs = ['StdAfx.h']
barresources = ['bar.rc', 'resource.h']
barmisc = ['bar_readme.txt']

dll = env.SharedLibrary(target='bar.dll', source=barsrcs)
buildtarget = [s for s in dll if str(s).endswith('dll')]
env.MSVSProject(
    target='Bar' + env['MSVSPROJECTSUFFIX'],
    srcs=barsrcs,
    incs=barincs,
    localincs=barlocalincs,
    resources=barresources,
    misc=barmisc,
    buildtarget=buildtarget,
    variant='Release',
)

DebugSettings

A dictionary of debug settings that get written to the .vcproj.user or the .vcxproj.user file, depending on the version installed. As for cmdargs, you can specify a DebugSettings dictionary per variant. If you give only one, it will be propagated to all variants.

Changed in version 2.4: Added the optional DebugSettings parameter.

Currently, only Visual Studio v9.0 and Visual Studio version v11 are implemented, for other versions no file is generated. To generate the user file, you just need to add a DebugSettings dictionary to the environment with the right parameters for your MSVS version. If the dictionary is empty, or does not contain any good value, no file will be generated.

Following is a more contrived example, involving the setup of a project for variants and DebugSettings:

# Assuming you store your defaults in a file
vars = Variables('variables.py')
msvcver = vars.args.get('vc', '9')

# Check command args to force one Microsoft Visual Studio version
if msvcver == '9' or msvcver == '11':
    env = Environment(MSVC_VERSION=msvcver + '.0', MSVC_BATCH=False)
else:
    env = Environment()

AddOption(
    '--userfile',
    action='store_true',
    dest='userfile',
    default=False,
    help="Create Visual C++ project file",
)

#
# 1. Configure your Debug Setting dictionary with options you want in the list
# of allowed options, for instance if you want to create a user file to launch
# a specific application for testing your dll with Microsoft Visual Studio 2008 (v9):
#
V9DebugSettings = {
    'Command': 'c:\\myapp\\using\\thisdll.exe',
    'WorkingDirectory': 'c:\\myapp\\using\\',
    'CommandArguments': '-p password',
    # 'Attach':'false',
    # 'DebuggerType':'3',
    # 'Remote':'1',
    # 'RemoteMachine': None,
    # 'RemoteCommand': None,
    # 'HttpUrl': None,
    # 'PDBPath': None,
    # 'SQLDebugging': None,
    # 'Environment': '',
    # 'EnvironmentMerge':'true',
    # 'DebuggerFlavor': None,
    # 'MPIRunCommand': None,
    # 'MPIRunArguments': None,
    # 'MPIRunWorkingDirectory': None,
    # 'ApplicationCommand': None,
    # 'ApplicationArguments': None,
    # 'ShimCommand': None,
    # 'MPIAcceptMode': None,
    # 'MPIAcceptFilter': None,
}

#
# 2. Because there are a lot of different options depending on the Microsoft
# Visual Studio version, if you use more than one version you have to
# define a dictionary per version, for instance if you want to create a user
# file to launch a specific application for testing your dll with Microsoft
# Visual Studio 2012 (v11):
#
V10DebugSettings = {
    'LocalDebuggerCommand': 'c:\\myapp\\using\\thisdll.exe',
    'LocalDebuggerWorkingDirectory': 'c:\\myapp\\using\\',
    'LocalDebuggerCommandArguments': '-p password',
    # 'LocalDebuggerEnvironment': None,
    # 'DebuggerFlavor': 'WindowsLocalDebugger',
    # 'LocalDebuggerAttach': None,
    # 'LocalDebuggerDebuggerType': None,
    # 'LocalDebuggerMergeEnvironment': None,
    # 'LocalDebuggerSQLDebugging': None,
    # 'RemoteDebuggerCommand': None,
    # 'RemoteDebuggerCommandArguments': None,
    # 'RemoteDebuggerWorkingDirectory': None,
    # 'RemoteDebuggerServerName': None,
    # 'RemoteDebuggerConnection': None,
    # 'RemoteDebuggerDebuggerType': None,
    # 'RemoteDebuggerAttach': None,
    # 'RemoteDebuggerSQLDebugging': None,
    # 'DeploymentDirectory': None,
    # 'AdditionalFiles': None,
    # 'RemoteDebuggerDeployDebugCppRuntime': None,
    # 'WebBrowserDebuggerHttpUrl': None,
    # 'WebBrowserDebuggerDebuggerType': None,
    # 'WebServiceDebuggerHttpUrl': None,
    # 'WebServiceDebuggerDebuggerType': None,
    # 'WebServiceDebuggerSQLDebugging': None,
}

#
# 3. Select the dictionary you want depending on the version of Visual Studio
# Files you want to generate.
#
if not env.GetOption('userfile'):
    dbgSettings = None
elif env.get('MSVC_VERSION', None) == '9.0':
    dbgSettings = V9DebugSettings
elif env.get('MSVC_VERSION', None) == '11.0':
    dbgSettings = V10DebugSettings
else:
    dbgSettings = None

#
# 4. Add the dictionary to the DebugSettings keyword.
#
barsrcs = ['bar.cpp', 'dllmain.cpp', 'stdafx.cpp']
barincs = ['targetver.h']
barlocalincs = ['StdAfx.h']
barresources = ['bar.rc', 'resource.h']
barmisc = ['ReadMe.txt']

dll = env.SharedLibrary(target='bar.dll', source=barsrcs)

env.MSVSProject(
    target='Bar' + env['MSVSPROJECTSUFFIX'],
    srcs=barsrcs,
    incs=barincs,
    localincs=barlocalincs,
    resources=barresources,
    misc=barmisc,
    buildtarget=[dll[0]] * 2,
    variant=('Debug|Win32', 'Release|Win32'),
    cmdargs=f'vc={msvcver}',
    DebugSettings=(dbgSettings, {}),
)

MSVSSolution(), env.MSVSSolution()

Build a Microsoft Visual Studio Solution file.

Builds a Visual Studio solution file based on the version of Visual Studio that is configured: either the latest installed version, or the version specified by $MSVC_VERSION in the construction environment. For Visual Studio 6, a .dsw file is generated. For Visual Studio .NET 2002 and later, it will generate a .sln file. Note there are multiple versioning schemes involved in the Microsoft compilation environment - see the description of $MSVC_VERSION for equivalences.

The solution file is a container for one or more projects, and follows the format described at https://learn.microsoft.com/en-us/visualstudio/extensibility/internals/solution-dot-sln-file^[5].

The following values must be specified:

target

The name of the target .dsw or .sln file. The correct suffix for the version of Visual Studio must be used, but the value $MSVSSOLUTIONSUFFIX will be defined to the correct value (see example below).

variant

The name of this particular variant, or a list of variant names (the latter is only supported for MSVS 7 solutions). These are typically things like "Debug" or "Release", but really can be anything you want. For MSVS 7 they may also specify target platform, like this "Debug|Xbox". Default platform is Win32.

projects

A list of project file names, or Project nodes returned by calls to the MSVSProject Builder, to be placed into the solution file. Note that these filenames need to be specified as strings, NOT as SCons File Nodes. This is because the solution file will be interpreted by MSBuild and by Visual Studio, which know nothing about SCons Node types.

In addition to the mandatory arguments above, the following optional values may be specified as keyword arguments:

auto_filter_projects

Under certain circumstances, solution file names or solution file nodes may be present in the projects argument list. When solution file names or nodes are present in the projects argument list, the generated solution file may contain erroneous Project records resulting in VS IDE error messages when opening the generated solution file. By default, an exception is raised when a solution file name or solution file node is detected in the projects argument list.

The accepted values for auto_filter_projects are:

None

An exception is raised when a solution file name or solution file node is detected in the projects argument list.

None is the default value.

True or evaluates True

Automatically remove solution file names and solution file nodes from the projects argument list.

False or evaluates False

Leave the solution file names and solution file nodes in the projects argument list. An exception is not raised.

When opening the generated solution file with the VS IDE, the VS IDE will likely report that there are erroneous Project records that are not supported or that need to be modified.

Example Usage:

env.MSVSSolution(
    target="Bar" + env["MSVSSOLUTIONSUFFIX"],
    projects=["bar" + env["MSVSPROJECTSUFFIX"]],
    variant="Release",
)

Ninja(), env.Ninja()

A special builder which adds a target to create a Ninja build file. The builder does not require any source files to be specified.

Note
This is an experimental feature. To enable it you must use one of the following methods

# On the command line
--experimental=ninja

# Or in your SConstruct
SetOption('experimental', 'ninja')

This functionality is subject to change and/or removal without deprecation cycle.

To use this tool you need to install the Python ninja package, as the tool by default depends on being able to do an import of the package This can be done via:

python -m pip install ninja

If called with no arguments, the builder will default to a target name of ninja.build.

If called with a single positional argument, scons will "deduce" the target name from that source argument, giving it the same name, and then ignore the source. This is the usual way to call the builder if a non-default target name is wanted.

If called with either the target= or source= keyword arguments, the value of the argument is taken as the target name. If called with both, the target= value is used and source= is ignored. If called with multiple sources, the source list will be ignored, since there is no way to deduce what the intent was; in this case the default target name will be used.

Available since scons 4.2.

Object(), env.Object()

A synonym for the StaticObject builder method.

Package(), env.Package()

Builds software distribution packages. A package is a container format which includes files to install along with metadata. Packaging is optional, and must be enabled by specifying the packaging tool. For example:

env = Environment(tools=['default', 'packaging'])

SCons can build packages in a number of well known packaging formats. The target package type may be selected with the $PACKAGETYPE construction variable or the --package-type command line option. The package type may be a list, in which case SCons will attempt to build packages for each type in the list. Example:

env.Package(PACKAGETYPE=['src_zip', 'src_targz'], ...other args...)

The currently supported packagers are:

msi	Microsoft Installer package
rpm	RPM Package Manager package
ipkg	Itsy Package Management package
tarbz2	bzip2-compressed tar file
targz	gzip-compressed tar file
tarxz	xz-compressed tar file
zip	zip file
src_tarbz2	bzip2-compressed tar file suitable as source to another packager
src_targz	gzip-compressed tar file suitable as source to another packager
src_tarxz	xz-compressed tar file suitable as source to another packager
src_zip	zip file suitable as source to another packager

The file list to include in the package may be specified with the source keyword argument. If omitted, the FindInstalledFiles function is called behind the scenes to select all files that have an Install, InstallAs or InstallVersionedLib Builder attached. If the target keyword argument is omitted, the target name(s) will be deduced from the package type(s).

The metadata comes partly from attributes of the files to be packaged, and partly from packaging tags. Tags can be passed as keyword arguments to the Package builder call, and may also be attached to files (or more accurately, Nodes representing files) with the Tag function. Some package-level tags are mandatory, and will lead to errors if omitted. The mandatory tags vary depending on the package type.

While packaging, the builder uses a temporary location named by the value of the $PACKAGEROOT variable - the package sources are copied there before packaging.

Packaging example:

env = Environment(tools=["default", "packaging"])
env.Install("/bin/", "my_program")
env.Package(
    NAME="foo",
    VERSION="1.2.3",
    PACKAGEVERSION=0,
    PACKAGETYPE="rpm",
    LICENSE="gpl",
    SUMMARY="balalalalal",
    DESCRIPTION="this should be really really long",
    X_RPM_GROUP="Application/fu",
    SOURCE_URL="https://foo.org/foo-1.2.3.tar.gz",
)

In this example, the target /bin/my_program created by the Install call would not be built by default since it is not under the project top directory. However, since no source is specified to the Package builder, it is selected for packaging by the default sources rule. Since packaging is done using $PACKAGEROOT, no write is actually done to the system's /bin directory, and the target will be selected since after rebasing to underneath $PACKAGEROOT it is now under the top directory of the project.

PCH(), env.PCH()

Builds a Microsoft Visual C++ precompiled header. Calling this builder returns a list of two target nodes: the PCH as the first element, and the object file as the second element. Normally the object file is ignored. The PCH builder is generally used in conjunction with the $PCH construction variable to force object files to use the precompiled header:

env['PCH'] = env.PCH('StdAfx.cpp')[0]

Note
This builder is specific to the PCH implementation in Microsoft Visual C++. Other compiler chains also implement precompiled header support, but PCH does not work with them at this time. As a result, the builder is only generated into the construction environment when Microsoft Visual C++ is being used as the compiler.

The builder only works correctly in a C++ project. The Microsoft implementation distinguishes between precompiled headers from C and C++. Use of the builder will cause the PCH generation to happen with a flag that tells cl.exe all of the files are C++ files; if that PCH file is then supplied when compiling a C source file, cl.exe will fail the build with a compatibility violation.

If possible, arrange the project so that a C++ source file passed to the PCH builder is not also included in the list of sources to be otherwise compiled in the project. SCons will correctly track that file in the dependency tree as a result of the PCH call, and (for MSVC 11.0 and greater) automatically add the corresponding object file to the link line. If the source list is automatically generated, for example using the Glob function, it may be necessary to remove that file from the list.

PDF(), env.PDF()

Builds a .pdf file from a .dvi input file (or, by extension, a .tex, .ltx, or .latex input file). The suffix specified by the $PDFSUFFIX construction variable (.pdf by default) is added automatically to the target if it is not already present. PDF is a single-source builder. Example:

# builds from aaa.tex
env.PDF(target = 'aaa.pdf', source = 'aaa.tex')
# builds bbb.pdf from bbb.dvi
env.PDF(target = 'bbb', source = 'bbb.dvi')

POInit(), env.POInit()

This builder is set up by the msginit tool. The builder initializes missing PO file(s) if $POAUTOINIT is set. If $POAUTOINIT is not set (the default), POInit prints instruction for the user (such as a translator), telling how the PO file should be initialized. In normal projects you should not use POInit and use POUpdate instead. POUpdate chooses intelligently between msgmerge(1) and msginit(1). POInit always uses msginit(1) and should be regarded as builder for special purposes or for temporary use (e.g. for quick, one time initialization of a bunch of PO files) or for tests. POInit is a single-source builder. The source parameter can also be omitted if $LINGUAS_FILE is set.

Target nodes defined through POInit are not built by default (they're Ignored from '.' node) but are added to special Alias ('po-create' by default). The alias name may be changed through the $POCREATE_ALIAS construction variable. All PO files defined through POInit may be easily initialized by scons po-create.

Example 1. Initialize en.po and pl.po from messages.pot:

env.POInit(['en', 'pl']) # messages.pot --> [en.po, pl.po]

Example 2. Initialize en.po and pl.po from foo.pot:

env.POInit(['en', 'pl'], ['foo']) # foo.pot --> [en.po, pl.po]

Example 3. Initialize en.po and pl.po from foo.pot but using the $POTDOMAIN construction variable:

env.POInit(['en', 'pl'], POTDOMAIN='foo') # foo.pot --> [en.po, pl.po]

Example 4. Initialize PO files for languages defined in LINGUAS file. The files will be initialized from template messages.pot:

env.POInit(LINGUAS_FILE=True)  # needs 'LINGUAS' file

Example 5. Initialize en.po and pl.pl PO files plus files for languages defined in LINGUAS file. The files will be initialized from template messages.pot:

env.POInit(['en', 'pl'], LINGUAS_FILE=True)

Example 6. You may preconfigure your environment first, and then initialize PO files:

env['POAUTOINIT'] = True
env['LINGUAS_FILE'] = True
env['POTDOMAIN'] = 'foo'
env.POInit()

which has same efect as:

env.POInit(POAUTOINIT=True, LINGUAS_FILE=True, POTDOMAIN='foo')

PostScript(), env.PostScript()

Builds a .ps file from a .dvi input file (or, by extension, a .tex, .ltx, or .latex input file). The suffix specified by the $PSSUFFIX construction variable (.ps by default) is added automatically to the target if it is not already present. PostScript is a single-source builder. Example:

# builds from aaa.tex
env.PostScript(target = 'aaa.ps', source = 'aaa.tex')
# builds bbb.ps from bbb.dvi
env.PostScript(target = 'bbb', source = 'bbb.dvi')

POTUpdate(), env.POTUpdate()

The builder is set up by the xgettext tool, part of the gettext toolset. The builder updates the target POT file if exists or creates it if it doesn't. The target node is not selected for building by default (e.g. scons .), but only on demand (i.e. when the given POT file is required or when special alias is invoked). This builder adds its target node (messages.pot, say) to a special alias (pot-update by default, see $POTUPDATE_ALIAS) so you can update/create them easily with scons pot-update. The file is not written until there is no real change in internationalized messages (or in comments that enter POT file).

Note
You may see xgettext(1) being invoked by the xgettext tool even if there is no real change in internationalized messages (so the POT file is not being updated). This happens every time a source file has changed. In such case we invoke xgettext(1) and compare its output with the content of POT file to decide whether the file should be updated or not.

Example 1. Let's create po/ directory and place following SConstruct script there:

# SConstruct in 'po/' subdir
env = Environment(tools=['default', 'xgettext'])
env.POTUpdate(['foo'], ['../a.cpp', '../b.cpp'])
env.POTUpdate(['bar'], ['../c.cpp', '../d.cpp'])

Then invoke scons few times:

$ scons             # Does not create foo.pot nor bar.pot
$ scons foo.pot     # Updates or creates foo.pot
$ scons pot-update  # Updates or creates foo.pot and bar.pot
$ scons -c          # Does not clean foo.pot nor bar.pot.

the results shall be as the comments above say.

Example 2. The target argument can be omitted, in which case the default target name messages.pot is used. The target may also be overridden by setting the $POTDOMAIN construction variable or providing it as an override to the POTUpdate builder:

# SConstruct script
env = Environment(tools=['default', 'xgettext'])
env['POTDOMAIN'] = "foo"
env.POTUpdate(source=["a.cpp", "b.cpp"])  # Creates foo.pot ...
env.POTUpdate(POTDOMAIN="bar", source=["c.cpp", "d.cpp"])  # and bar.pot

Example 3. The source parameter may also be omitted, if it is specified in a separate file, for example POTFILES.in:

# POTFILES.in in 'po/' subdirectory
../a.cpp
../b.cpp
# end of file

The name of the file (POTFILES.in) containing the list of sources is provided via $XGETTEXTFROM:

# SConstruct file in 'po/' subdirectory
env = Environment(tools=['default', 'xgettext'])
env.POTUpdate(XGETTEXTFROM='POTFILES.in')

Example 4. You can use $XGETTEXTPATH to define the source search path. Assume, for example, that you have files a.cpp, b.cpp, po/SConstruct, po/POTFILES.in. Then your POT-related files could look like this:

# POTFILES.in in 'po/' subdirectory
a.cpp
b.cpp
# end of file

# SConstruct file in 'po/' subdirectory
env = Environment(tools=['default', 'xgettext'])
env.POTUpdate(XGETTEXTFROM='POTFILES.in', XGETTEXTPATH='../')

Example 5. Multiple search directories may be defined as a list, i.e. XGETTEXTPATH=['dir1', 'dir2', ...]. The order in the list determines the search order of source files. The path to the first file found is used.

Let's create 0/1/po/SConstruct script:

# SConstruct file in '0/1/po/' subdirectory
env = Environment(tools=['default', 'xgettext'])
env.POTUpdate(XGETTEXTFROM='POTFILES.in', XGETTEXTPATH=['../', '../../'])

and 0/1/po/POTFILES.in:

# POTFILES.in in '0/1/po/' subdirectory
a.cpp
# end of file

Write two *.cpp files, the first one is 0/a.cpp:

/* 0/a.cpp */
gettext("Hello from ../../a.cpp")

and the second is 0/1/a.cpp:

/* 0/1/a.cpp */
gettext("Hello from ../a.cpp")

then run scons. You'll obtain 0/1/po/messages.pot with the message "Hello from ../a.cpp". When you reverse order in $XGETTEXTFOM, i.e. when you write SConscript as

# SConstruct file in '0/1/po/' subdirectory
env = Environment(tools=['default', 'xgettext'])
env.POTUpdate(XGETTEXTFROM='POTFILES.in', XGETTEXTPATH=['../../', '../'])

then the messages.pot will contain msgid "Hello from ../../a.cpp" line and not msgid "Hello from ../a.cpp".

POUpdate(), env.POUpdate()

The builder is set up by the msgmerge tool. part of the gettext toolset. The builder updates PO files with msgmerge(1), or initializes missing PO files as described in the documentation of the msginit tool and the POInit builder (see also $POAUTOINIT). POUpdate is a single-source builder. The source parameter can also be omitted if $LINGUAS_FILE is set.

The target nodes are not selected for building by default (e.g. scons .). Instead, they are added automatically to special Alias ('po-update' by default). The alias name may be changed through the $POUPDATE_ALIAS construction variable. You can easily update PO files in your project by scons po-update. Note that POUpdate does not add its targets to the po-create alias as POInit does.

Example 1. Update en.po and pl.po from messages.pot template (see also $POTDOMAIN), assuming that the later one exists or there is rule to build it (see POTUpdate):

env.POUpdate(['en','pl'])  # messages.pot --> [en.po, pl.po]

Example 2. Update en.po and pl.po from foo.pot template:

env.POUpdate(['en', 'pl'], ['foo'])  # foo.pot -->  [en.po, pl.pl]

Example 3. Update en.po and pl.po from foo.pot (another version):

env.POUpdate(['en', 'pl'], POTDOMAIN='foo')  # foo.pot -- > [en.po, pl.pl]

Example 4. Update files for languages defined in LINGUAS file. The files are updated from messages.pot template:

env.POUpdate(LINGUAS_FILE=True)  # needs 'LINGUAS' file

Example 5. Same as above, but update from foo.pot template:

env.POUpdate(LINGUAS_FILE=True, source=['foo'])

Example 6. Update en.po and pl.po plus files for languages defined in LINGUAS file. The files are updated from messages.pot template:

# produce 'en.po', 'pl.po' + files defined in 'LINGUAS':
env.POUpdate(['en', 'pl' ], LINGUAS_FILE=True)

Example 7. Use $POAUTOINIT to automatically initialize PO file if it doesn't exist:

env.POUpdate(LINGUAS_FILE=True, POAUTOINIT=True)

Example 8. Update PO files for languages defined in LINGUAS file. The files are updated from foo.pot template. All necessary settings are pre-configured via environment.

env['POAUTOINIT'] = True
env['LINGUAS_FILE'] = True
env['POTDOMAIN'] = 'foo'
env.POUpdate()

Program(), env.Program()

Builds an executable given one or more object files or C, C++, D, or Fortran source files. If any C, C++, D or Fortran source files are specified, then they will be automatically compiled to object files using the Object builder method; see that builder method's description for a list of legal source file suffixes and how they are interpreted. The target executable file prefix, specified by the $PROGPREFIX construction variable (nothing by default), and suffix, specified by the $PROGSUFFIX construction variable (by default, .exe on Windows systems, nothing on POSIX systems), are automatically added to the target if not already present. Example:

env.Program(target='foo', source=['foo.o', 'bar.c', 'baz.f'])

ProgramAllAtOnce(), env.ProgramAllAtOnce()

Builds an executable from D sources without first creating individual objects for each file.

D sources can be compiled file-by-file as C and C++ source are, and D is integrated into the scons Object and Program builders for this model of build. D codes can though do whole source meta-programming (some of the testing frameworks do this). For this it is imperative that all sources are compiled and linked in a single call to the D compiler. This builder serves that purpose.

    env.ProgramAllAtOnce('executable', ['mod_a.d, mod_b.d', 'mod_c.d'])

This command will compile the modules mod_a, mod_b, and mod_c in a single compilation process without first creating object files for the modules. Some of the D compilers will create executable.o others will not.

RES(), env.RES()

Builds a Microsoft Visual C++ resource file. This builder method is only provided when Microsoft Visual C++ or MinGW is being used as the compiler. The .res (or .o for MinGW) suffix is added to the target name if no other suffix is given. The source file is scanned for implicit dependencies as though it were a C file. Example:

env.RES('resource.rc')

RMIC(), env.RMIC()

Builds stub and skeleton class files for remote objects from Java .class files. The target is a directory relative to which the stub and skeleton class files will be written. The source can be the names of .class files, or the objects return from the Java builder method.

If the construction variable $JAVACLASSDIR is set, either in the environment or in the call to the RMIC builder method itself, then the value of the variable will be stripped from the beginning of any .class file names.

classes = env.Java(target='classdir', source='src')
env.RMIC(target='outdir1', source=classes)
env.RMIC(
    target='outdir2',
    source=['package/foo.class', 'package/bar.class'],
)
env.RMIC(
    target='outdir3',
    source=['classes/foo.class', 'classes/bar.class'],
    JAVACLASSDIR='classes',
)

RPCGenClient(), env.RPCGenClient()

Generates an RPC client stub (_clnt.c) file from a specified RPC (.x) source file. Because rpcgen only builds output files in the local directory, the command will be executed in the source file's directory by default.

# Builds src/rpcif_clnt.c
env.RPCGenClient('src/rpcif.x')

RPCGenHeader(), env.RPCGenHeader()

Generates an RPC header (.h) file from a specified RPC (.x) source file. Because rpcgen only builds output files in the local directory, the command will be executed in the source file's directory by default.

# Builds src/rpcif.h
env.RPCGenHeader('src/rpcif.x')

RPCGenService(), env.RPCGenService()

Generates an RPC server-skeleton (_svc.c) file from a specified RPC (.x) source file. Because rpcgen only builds output files in the local directory, the command will be executed in the source file's directory by default.

# Builds src/rpcif_svc.c
env.RPCGenClient('src/rpcif.x')

RPCGenXDR(), env.RPCGenXDR()

Generates an RPC XDR routine (_xdr.c) file from a specified RPC (.x) source file. Because rpcgen only builds output files in the local directory, the command will be executed in the source file's directory by default.

# Builds src/rpcif_xdr.c
env.RPCGenClient('src/rpcif.x')

SharedLibrary(), env.SharedLibrary()

Builds a shared library given one or more object files and/or C, C++, D or Fortran source files. Any source files listed in the source parameter will be automatically compiled to object files suitable for use in a shared library. Any object files listed in the source parameter must have been built for a shared library (that is, using the SharedObject builder method). scons will raise an error if there is any mismatch.

The target library file prefix, specified by the $SHLIBPREFIX construction variable (by default, lib on POSIX systems, nothing on Windows systems), and suffix, specified by the $SHLIBSUFFIX construction variable (by default, .dll on Windows systems, .so on POSIX systems), are automatically added (if not already present) to the target name to make up the library filename. On a POSIX system, if the $SHLIBVERSION construction variable is set, it is appended (following a period) to the resulting library name.

Example:

env.SharedLibrary(target='bar', source=['bar.c', 'foo.o'])

On Windows systems, the SharedLibrary builder method will always build an import library (.lib) in addition to the shared library (.dll), adding a .lib library with the same basename if there is not already a .lib file explicitly listed in the targets.

On Cygwin systems, the SharedLibrary builder method will always build an import library (.dll.a) in addition to the shared library (.dll), adding a .dll.a library with the same basename if there is not already a .dll.a file explicitly listed in the targets.

On some platforms, there is a distinction between a shared library (loaded automatically by the system to resolve external references) and a loadable module (explicitly loaded by user action). For maximum portability, use the LoadableModule builder for the latter.

If $SHLIBVERSION is defined, a versioned shared library is created. This modifies $SHLINKFLAGS as required, adds the version number to the library name, and creates any symbolic links that are needed.

env.SharedLibrary(target='bar', source=['bar.c', 'foo.o'], SHLIBVERSION='1.5.2')

On a POSIX system, supplying a simple version string (no dots) creates exactly one symbolic link: SHLIBVERSION="1" would create (for example) library libbar.so.1 and symbolic link libbar.so. Supplying a dotted version string will create two symbolic links (irrespective of the number of segments in the version): SHLIBVERSION="1.5.2" for the same library would create library libbar.so.1.5.2 and symbolic links libbar.so and libbar.so.1. A Darwin (OSX) system creates one symlink in either case, for the second example the library would be libbar.1.5.2.dylib and the link would be libbar.dylib.

On Windows systems, specifying the register=1 keyword argument will cause the .dll to be registered after it is built. The command that is run is determined by the $REGSVR construction variable (regsvr32 by default), and the flags passed are determined by $REGSVRFLAGS. By default, $REGSVRFLAGS includes the /s option, to prevent dialogs from popping up and requiring user attention when it is run. If you change $REGSVRFLAGS, be sure to include the /s option. For example,

env.SharedLibrary(target='bar', source=['bar.cxx', 'foo.obj'], register=1)

will register bar.dll as a COM object when it is done linking it.

SharedObject(), env.SharedObject()

Builds an object file intended for inclusion in a shared library. Source files must have one of the same set of extensions specified above for the StaticObject builder method. On some platforms building a shared object requires additional compiler option (e.g. -fPIC for gcc) in addition to those needed to build a normal (static) object, but on some platforms there is no difference between a shared object and a normal (static) one. When there is a difference, SCons will only allow shared objects to be linked into a shared library, and will use a different suffix for shared objects. On platforms where there is no difference, SCons will allow both normal (static) and shared objects to be linked into a shared library, and will use the same suffix for shared and normal (static) objects. The target object file prefix, specified by the $SHOBJPREFIX construction variable (by default, the same as $OBJPREFIX), and suffix, specified by the $SHOBJSUFFIX construction variable, are automatically added to the target if not already present. Examples:

env.SharedObject(target='ddd', source='ddd.c')
env.SharedObject(target='eee.o', source='eee.cpp')
env.SharedObject(target='fff.obj', source='fff.for')

Note that the source files will be scanned according to the suffix mappings in the SourceFileScanner object. See the manpage section "Scanner Objects" for more information.

StaticLibrary(), env.StaticLibrary()

Builds a static library given one or more object files or C, C++, D or Fortran source files. If any source files are given, then they will be automatically compiled to object files. The static library file prefix, specified by the $LIBPREFIX construction variable (by default, lib on POSIX systems, nothing on Windows systems), and suffix, specified by the $LIBSUFFIX construction variable (by default, .lib on Windows systems, .a on POSIX systems), are automatically added to the target if not already present. Example:

env.StaticLibrary(target='bar', source=['bar.c', 'foo.o'])

Any object files listed in the source must have been built for a static library (that is, using the StaticObject builder method). scons will raise an error if there is any mismatch.

StaticObject(), env.StaticObject()

Builds a static object file from one or more C, C++, D, or Fortran source files. Source files must have one of the following extensions:

  .asm    assembly language file
  .ASM    assembly language file
  .c      C file
  .C      Windows:  C file
          POSIX:  C++ file
  .cc     C++ file
  .cpp    C++ file
  .cxx    C++ file
  .cxx    C++ file
  .c++    C++ file
  .C++    C++ file
  .d      D file
  .f      Fortran file
  .F      Windows:  Fortran file
          POSIX:  Fortran file + C pre-processor
  .for    Fortran file
  .FOR    Fortran file
  .fpp    Fortran file + C pre-processor
  .FPP    Fortran file + C pre-processor
  .m      Object C file
  .mm     Object C++ file
  .s      assembly language file
  .S      Windows:  assembly language file
          ARM: CodeSourcery Sourcery Lite
  .sx     assembly language file + C pre-processor
          POSIX:  assembly language file + C pre-processor
  .spp    assembly language file + C pre-processor
  .SPP    assembly language file + C pre-processor

The target object file prefix, specified by the $OBJPREFIX construction variable (nothing by default), and suffix, specified by the $OBJSUFFIX construction variable (.obj on Windows systems, .o on POSIX systems), are automatically added to the target if not already present. Examples:

env.StaticObject(target='aaa', source='aaa.c')
env.StaticObject(target='bbb.o', source='bbb.c++')
env.StaticObject(target='ccc.obj', source='ccc.f')

Note that the source files will be scanned according to the suffix mappings in the SourceFileScanner object. See the manpage section "Scanner Objects" for more information.

Substfile(), env.Substfile()

The Substfile builder creates a single text file from a template consisting of a file or set of files (or nodes), replacing text using the $SUBST_DICT construction variable (if set). If a set, they are concatenated into the target file using the value of the $LINESEPARATOR construction variable as a separator between contents; the separator is not emitted after the contents of the last file. Nested lists of source files are flattened. See also Textfile.

By default, the target file encoding is "utf-8" and can be changed by $FILE_ENCODING Examples:

If a single source file name is specified and has a .in suffix, the suffix is stripped and the remainder of the name is used as the default target name.

The prefix and suffix specified by the $SUBSTFILEPREFIX and $SUBSTFILESUFFIX construction variables (an empty string by default in both cases) are automatically added to the target if they are not already present.

If a construction variable named $SUBST_DICT is present, it may be either a Python dictionary or a sequence of (key, value) tuples. If it is a dictionary it is converted into a list of tuples with unspecified order, so if one key is a prefix of another key or if one substitution could be further expanded by another substitution, it is unpredictable whether the expansion will occur.

Any occurrences of a key in the source are replaced by the corresponding value, which may be a Python callable function or a string. If the value is a callable, it is called with no arguments to get a string. Strings are subst-expanded and the result replaces the key.

env = Environment(tools=['default'])

env['prefix'] = '/usr/bin'
script_dict = {'@prefix@': '/bin', '@exec_prefix@': '$prefix'}
env.Substfile('script.in', SUBST_DICT=script_dict)

conf_dict = {'%VERSION%': '1.2.3', '%BASE%': 'MyProg'}
env.Substfile('config.h.in', conf_dict, SUBST_DICT=conf_dict)

# UNPREDICTABLE - one key is a prefix of another
bad_foo = {'$foo': '$foo', '$foobar': '$foobar'}
env.Substfile('foo.in', SUBST_DICT=bad_foo)

# PREDICTABLE - keys are applied longest first
good_foo = [('$foobar', '$foobar'), ('$foo', '$foo')]
env.Substfile('foo.in', SUBST_DICT=good_foo)

# UNPREDICTABLE - one substitution could be further expanded
bad_bar = {'@bar@': '@soap@', '@soap@': 'lye'}
env.Substfile('bar.in', SUBST_DICT=bad_bar)

# PREDICTABLE - substitutions are expanded in order
good_bar = (('@bar@', '@soap@'), ('@soap@', 'lye'))
env.Substfile('bar.in', SUBST_DICT=good_bar)

# the SUBST_DICT may be in common (and not an override)
substutions = {}
subst = Environment(tools=['textfile'], SUBST_DICT=substitutions)
substitutions['@foo@'] = 'foo'
subst['SUBST_DICT']['@bar@'] = 'bar'
subst.Substfile(
    'pgm1.c',
    [Value('#include "@foo@.h"'), Value('#include "@bar@.h"'), "common.in", "pgm1.in"],
)
subst.Substfile(
    'pgm2.c',
    [Value('#include "@foo@.h"'), Value('#include "@bar@.h"'), "common.in", "pgm2.in"],
)

Tar(), env.Tar()

Builds a tar archive of the specified files and/or directories. Unlike most builder methods, the Tar builder method may be called multiple times for a given target; each additional call adds to the list of entries that will be built into the archive. Any source directories will be scanned for changes to any on-disk files, regardless of whether or not scons knows about them from other Builder or function calls.

env.Tar('src.tar', 'src')

# Create the stuff.tar file.
env.Tar('stuff', ['subdir1', 'subdir2'])
# Also add "another" to the stuff.tar file.
env.Tar('stuff', 'another')

# Set TARFLAGS to create a gzip-filtered archive.
env = Environment(TARFLAGS = '-c -z')
env.Tar('foo.tar.gz', 'foo')

# Also set the suffix to .tgz.
env = Environment(TARFLAGS = '-c -z',
                  TARSUFFIX = '.tgz')
env.Tar('foo')

Textfile(), env.Textfile()

The Textfile builder generates a single text file from a template consisting of a list of strings, replacing text using the $SUBST_DICT construction variable (if set) - see Substfile for a description of replacement. The strings will be separated in the target file using the value of the $LINESEPARATOR construction variable; the line separator is not emitted after the last string. Nested lists of source strings are flattened. Source strings need not literally be Python strings: they can be Nodes or Python objects that convert cleanly to Value nodes.

The prefix and suffix specified by the $TEXTFILEPREFIX and $TEXTFILESUFFIX construction variables (by default an empty string and .txt, respectively) are automatically added to the target if they are not already present.

By default, the target file encoding is "utf-8" and can be changed by $FILE_ENCODING Examples:

# builds/writes foo.txt
env.Textfile(target='foo.txt', source=['Goethe', 42, 'Schiller'])

# builds/writes bar.txt
env.Textfile(target='bar', source=['lalala', 'tanteratei'], LINESEPARATOR='|*')

# nested lists are flattened automatically
env.Textfile(target='blob', source=['lalala', ['Goethe', 42, 'Schiller'], 'tanteratei'])

# files may be used as input by wrapping them in File()
env.Textfile(
    target='concat',  # concatenate files with a marker between
    source=[File('concat1'), File('concat2')],
    LINESEPARATOR='====================\n',
)

Results:

foo.txt

  Goethe
  42
  Schiller

bar.txt

  lalala|*tanteratei

blob.txt

  lalala
  Goethe
  42
  Schiller
  tanteratei

Translate(), env.Translate()

This pseudo-Builder is part of the gettext toolset. The builder extracts internationalized messages from source files, updates the POT template (if necessary) and then updates PO translations (if necessary). If $POAUTOINIT is set, missing PO files will be automatically created (i.e. without translator person intervention). The variables $LINGUAS_FILE and $POTDOMAIN are taken into account too. All other construction variables used by POTUpdate, and POUpdate work here too.

Example 1. The simplest way is to specify input files and output languages inline in a SCons script when invoking Translate:

# SConscript in 'po/' directory
env = Environment(tools=["default", "gettext"])
env['POAUTOINIT'] = True
env.Translate(['en', 'pl'], ['../a.cpp', '../b.cpp'])

Example 2. If you wish, you may also stick to the conventional style known from autotools, i.e. using POTFILES.in and LINGUAS files to specify the targets and sources:

# LINGUAS
en pl
# end

# POTFILES.in
a.cpp
b.cpp
# end

# SConscript
env = Environment(tools=["default", "gettext"])
env['POAUTOINIT'] = True
env['XGETTEXTPATH'] = ['../']
env.Translate(LINGUAS_FILE=True, XGETTEXTFROM='POTFILES.in')

The last approach is perhaps the recommended one. It allows easily split internationalization/localization onto separate SCons scripts, where a script in source tree is responsible for translations (from sources to PO files) and script(s) under variant directories are responsible for compilation of PO to MO files to and for installation of MO files. The "gluing factor" synchronizing these two scripts is then the content of LINGUAS file. Note, that the updated POT and PO files are usually going to be committed back to the repository, so they must be updated within the source directory (and not in variant directories). Additionally, the file listing of po/ directory contains LINGUAS file, so the source tree looks familiar to translators, and they may work with the project in their usual way.

Example 3. Let's prepare a development tree as below

 project/
  + SConstruct
  + build/
  + src/
      + po/
          + SConscript
          + SConscript.i18n
          + POTFILES.in
          + LINGUAS

with build being the variant directory. Write the top-level SConstruct script as follows

# SConstruct
env = Environment(tools=["default", "gettext"])
VariantDir('build', 'src', duplicate=False)
env['POAUTOINIT'] = True
SConscript('src/po/SConscript.i18n', exports='env')
SConscript('build/po/SConscript', exports='env')

the src/po/SConscript.i18n as

# src/po/SConscript.i18n
Import('env')
env.Translate(LINGUAS_FILE=True, XGETTEXTFROM='POTFILES.in', XGETTEXTPATH=['../'])

and the src/po/SConscript

# src/po/SConscript
Import('env')
env.MOFiles(LINGUAS_FILE=True)

Such a setup produces POT and PO files under the source tree in src/po/ and binary MO files under the variant tree in build/po/. This way the POT and PO files are separated from other output files, which must not be committed back to source repositories (e.g. MO files).

Note
In the above example, the PO files are not updated, nor created automatically when you issue the command scons .. The files must be updated (created) by hand via scons po-update and then MO files can be compiled by running scons ..

TypeLibrary(), env.TypeLibrary()

Builds a Windows type library (.tlb) file from an input IDL file (.idl). In addition, it will build the associated interface stub and proxy source files, naming them according to the base name of the .idl file. For example,

env.TypeLibrary(source="foo.idl")

Will create foo.tlb, foo.h, foo_i.c, foo_p.c and foo_data.c files.

Uic(), env.Uic()

Builds a header file, an implementation file and a moc file from an ui file. and returns the corresponding nodes in the that order. This builder is only available after using the tool qt3. Note: you can specify .ui files directly as source files to the Program, Library and SharedLibrary builders without using this builder. Using this builder lets you override the standard naming conventions (be careful: prefixes are always prepended to names of built files; if you don't want prefixes, you may set them to ``). See the $QT3DIR variable for more information. Example:

env.Uic('foo.ui')  # -> ['foo.h', 'uic_foo.cc', 'moc_foo.cc']
env.Uic(
    target=Split('include/foo.h gen/uicfoo.cc gen/mocfoo.cc'),
    source='foo.ui'
)  # -> ['include/foo.h', 'gen/uicfoo.cc', 'gen/mocfoo.cc']

Zip(), env.Zip()

Builds a zip archive of the specified files and/or directories. Unlike most builder methods, the Zip builder method may be called multiple times for a given target; each additional call adds to the list of entries that will be built into the archive. Any source directories will be scanned for changes to any on-disk files, regardless of whether or not scons knows about them from other Builder or function calls.

env.Zip('src.zip', 'src')

# Create the stuff.zip file.
env.Zip('stuff', ['subdir1', 'subdir2'])
# Also add "another" to the stuff.tar file.
env.Zip('stuff', 'another')

All targets of builder methods automatically depend on their sources. An explicit dependency can be specified using the env.Depends method of a construction environment (see below).

In addition, scons automatically scans source files for various programming languages, so the dependencies do not need to be specified explicitly. By default, SCons can C source files, C++ source files, Fortran source files with .F (POSIX systems only), .fpp, or .FPP file extensions, and assembly language files with .S (POSIX systems only), .spp, or .SPP files extensions for C preprocessor dependencies. SCons also has default support for scanning D source files, You can also write your own Scanners to add support for additional source file types. These can be added to the default Scanner object used by the Object, StaticObject and SharedObject Builders by adding them to the SourceFileScanner object. See the section called “Scanner Objects” for more information about defining your own Scanner objects and using the SourceFileScanner object.

SCons provides a variety of construction environment methods and global functions to manipulate the build configuration. Often, a construction environment method and a global function with the same name exist for convenience. In this section, both forms are shown if the function can be called in either way. The documentation style for these is as follows:

Function(arguments, [optional arguments, ...])  # Global function
env.Function(arguments, [optional arguments, ...])  # Environment method

In these function signatures, arguments in brackets ([]) are optional, and ellipses (...) indicate possible repetition. Positional vs. keyword arguments are usually detailed in the following text, not in the signature itself. The Python positional-only (/) and keyword-only (*) markers are not used.

When the Python keyword=value style is shown, it can have two meanings. If the keyword argument is known to the function, the value is the default for that argument if it is omitted. If the keyword is unknown to the function, some methods treat it as a construction variable assignment; otherwise an exception is raised for an unknown argument.

A global function and a same-named construction environment method have the same base functionality, with two key differences:

1. Construction environment methods that change the environment act on the environment instance from which they are called, while the corresponding global function acts on a special “hidden” construction environment called the Default Environment. In some cases, the global function may take an initial argument giving the object to operate on.
2. String-valued arguments (including strings in list-valued arguments) are subject to construction variable expansion by the environment method form; variable expansion is not immediately performed in the global function. For example, Default('$MYTARGET') adds '$MYTARGET' to the list of default targets, while if the value in env of MYTARGET is 'mine', env.Default('$MYTARGET' adds 'mine' to the default targets. For more details on construction variable expansion, see the Construction variables section.

Global functions are automatically in scope inside SConscript files. If your project adds Python modules that you include via the Python import statement from an SConscript file, such code will need to add the functions to that module’s global scope explicitly. You can do that by adding the following import to the Python module: from SCons.Script import *.

SCons provides the following construction environment methods and global functions. The list can be augmented on a project basis using AddMethod

Action(action, [output, [var, ...]] [key=value, ...]), env.Action(action, [output, [var, ...]] [key=value, ...])

A factory function to create an Action object for the specified action. See the manpage section "Action Objects" for a complete explanation of the arguments and behavior.

Note that the env.Action form of the invocation will expand construction variables in any argument strings, including the action argument, at the time it is called using the construction variables in the construction environment through which env.Action was called. The Action global function form delays all variable expansion until the Action object is actually used.

AddMethod(object, function, [name]), env.AddMethod(function, [name])

Adds function to an object as a method. function will be called with an instance object as the first argument as for other methods. If name is given, it is used as the name of the new method, else the name of function is used.

When the global function AddMethod is called, the object to add the method to must be passed as the first argument; typically this will be Environment, in order to create a method which applies to all construction environments subsequently constructed. When called using the env.AddMethod form, the method is added to the specified construction environment only. Added methods propagate through env.Clone calls.

More examples:

# Function to add must accept an instance argument.
# The Python convention is to call this 'self'.
def my_method(self, arg):
    print("my_method() got", arg)

# Use the global function to add a method to the Environment class:
AddMethod(Environment, my_method)
env = Environment()
env.my_method('arg')

# Use the optional name argument to set the name of the method:
env.AddMethod(my_method, 'other_method_name')
env.other_method_name('another arg')

AddOption(opt_str, ..., attr=value, ...)

Adds a local (project-specific) command-line option. One or more opt_str values are the strings representing how the option can be called, while the keyword arguments define attributes of the option. For the most part these are the same as for the OptionParser.add_option method in the standard Python library module optparse, but with a few additional capabilities noted below. See the optparse documentation^[6] for a thorough discussion of its option-processing capabilities. All options added through AddOption are placed in a special "Local Options" option group.

In addition to the arguments and values supported by the optparse add_option method, AddOption allows setting the nargs keyword value to a string '?' (question mark) to indicate that the option argument for that option string may be omitted. If the option string is present on the command line but has no matching option argument, the value of the const keyword argument is produced as the value of the option. If the option string is omitted from the command line, the value of the default keyword argument is produced, as usual; if there is no default keyword argument in the AddOption call, None is produced.

optparse recognizes abbreviations of long option names, as long as they can be unambiguously resolved. For example, if add_option is called to define a --devicename option, it will recognize --device, --dev and so forth as long as there is no other option which could also match to the same abbreviation. Options added via AddOption do not support the automatic recognition of abbreviations. Instead, to allow specific abbreviations, include them as synonyms in the AddOption call itself.

Once a new command-line option has been added with AddOption, the option value may be accessed using GetOption or env.GetOption. If the settable=True argument was supplied in the AddOption call, the value may also be set later using SetOption or env.SetOption, if conditions in an SConscript file require overriding any default value. Note however that a value specified on the command line will always override a value set in an SConscript file.

Changed in 4.8.0: added the settable keyword argument to enable an added option to be settable via SetOption.

Help text for an option is a combination of the string supplied in the help keyword argument to AddOption and information collected from the other keyword arguments. Such help is displayed if the -h command line option is used (but not with -H). Help for all local options is displayed under the separate heading Local Options. The options are unsorted - they will appear in the help text in the order in which the AddOption calls occur.

Example:

AddOption(
    '--prefix',
    dest='prefix',
    nargs=1,
    type='string',
    action='store',
    metavar='DIR',
    help='installation prefix',
)
env = Environment(PREFIX=GetOption('prefix'))

For that example, the following help text would be produced:

Local Options:
  --prefix=DIR                installation prefix

Help text for local options may be unavailable if the Help function has been called, see the Help documentation for details.

Note
As an artifact of the internal implementation, the behavior of options added by AddOption which take option arguments is undefined if whitespace (rather than an = sign) is used as the separator on the command line. Users should avoid such usage; it is recommended to add a note to this effect to project documentation if the situation is likely to arise. In addition, if the nargs keyword is used to specify more than one following option argument (that is, with a value of 2 or greater), such arguments would necessarily be whitespace separated, triggering the issue. Developers should not use AddOption this way. Future versions of SCons will likely forbid such usage.

AddPostAction(target, action), env.AddPostAction(target, action)

Arranges for the specified action to be performed after the specified target has been built. action may be an Action object, or anything that can be converted into an Action object. See the manpage section "Action Objects" for a complete explanation.

When multiple targets are supplied, the action may be called multiple times, once after each action that generates one or more targets in the list.

foo = Program('foo.c')
# remove execute permission from binary:
AddPostAction(foo, Chmod('$TARGET', "a-x"))

AddPreAction(target, action), env.AddPreAction(target, action)

Arranges for the specified action to be performed before the specified target is built. action may be an Action object, or anything that can be converted into an Action object. See the manpage section "Action Objects" for a complete explanation.

When multiple targets are specified, the action(s) may be called multiple times, once before each action that generates one or more targets in the list.

Note that if any of the targets are built in multiple steps, the action will be invoked just before the "final" action that specifically generates the specified target(s). For example, when building an executable program from a specified source .c file via an intermediate object file:

foo = Program('foo.c')
AddPreAction(foo, 'pre_action')

The specified pre_action would be executed before scons calls the link command that actually generates the executable program binary foo, not before compiling the foo.c file into an object file.

Alias(alias, [source, [action]]), env.Alias(alias, [source, [action]])

Creates an alias target that can be used as a reference to zero or more other targets, specified by the optional source parameter. Aliases provide a way to give a shorter or more descriptive name to specific targets, and to group multiple targets under a single name. The alias name, or an Alias Node object, may be used as a dependency of any other target, including another alias.

alias and source may each be a string or Node object, or a list of strings or Node objects; if Nodes are used for alias they must be Alias nodes. If source is omitted, the alias is created but has no reference; if selected for building this will result in a “Nothing to be done.” message. An empty alias can be used to define the alias in a visible place in the project; it can later be appended to in a subsidiary SConscript file with the actual target(s) to refer to. The optional action parameter specifies an action or list of actions that will be executed whenever the any of the alias targets are out-of-date.

Alias can be called for an existing alias, which appends the alias and/or action arguments to the existing lists for that alias.

Returns a list of Alias Node objects representing the alias(es), which exist outside of any physical file system. The alias name space is separate from the name space for tangible targets; to avoid confusion do not reuse target names as alias names.

Examples:

Alias('install')
Alias('install', '/usr/bin')
Alias(['install', 'install-lib'], '/usr/local/lib')

env.Alias('install', ['/usr/local/bin', '/usr/local/lib'])
env.Alias('install', ['/usr/local/man'])

env.Alias('update', ['file1', 'file2'], "update_database $SOURCES")

AllowSubstExceptions([exception, ...])

Specifies the exceptions that will be ignored when expanding construction variables. By default, any construction variable expansions that generate a NameError or IndexError exception will expand to a '' (an empty string) and not cause scons to fail. All exceptions not in the specified list will generate an error message and terminate processing.

If AllowSubstExceptions is called multiple times, each call completely overwrites the previous list of ignored exceptions. Calling it with no arguments means no exceptions will be ignored.

Example:

# Requires that all construction variable names exist.
# (You may wish to do this if you want to enforce strictly
# that all construction variables must be defined before use.)
AllowSubstExceptions()

# Also allow a string containing a zero-division expansion
# like '${1 / 0}' to evaluate to ''.
AllowSubstExceptions(IndexError, NameError, ZeroDivisionError)

AlwaysBuild(target, ...), env.AlwaysBuild(target, ...)

Marks each given target so that it is always assumed to be out-of-date, and will always be rebuilt if needed. Note, however, that AlwaysBuild does not add its target(s) to the default target list, so the targets will only be built if they are specified on the command line, or are a dependent of a target specified on the command line--but they will always be built if so specified. Multiple targets can be passed in to a single call to AlwaysBuild.

env.Append(key=val, [...])

Appends value(s) intelligently to construction variables in env. The construction variables and values to add to them are passed as key=val pairs (Python keyword arguments). env.Append is designed to allow adding values without having to think about the data type of an existing construction variable. Regular Python syntax can also be used to manipulate the construction variable, but for that you may need to know the types involved, for example pure Python lets you directly "add" two lists of strings, but adding a string to a list or a list to a string requires different syntax - things Append takes care of. Some pre-defined construction variables do have type expectations based on how SCons will use them: for example $CPPDEFINES is often a string or a list of strings, but can also be a list of tuples or a dictionary; while $LIBEMITTER is expected to be a callable or list of callables, and $BUILDERS is expected to be a dictionary. Consult the documentation for the various construction variables for more details.

The following descriptions apply to both the Append and Prepend methods, as well as their Unique variants, with the differences being the insertion point of the added values and whether duplication is allowed.

val can be almost any type. If env does not have a construction variable named key, then key is simply stored with a value of val. Otherwise, val is combined with the existing value, possibly converting into an appropriate type which can hold the expanded contents. There are a few special cases to be aware of. Normally, when two strings are combined, the result is a new string containing their concatenation (and you are responsible for supplying any needed separation); however, the contents of $CPPDEFINES will be post-processed by adding a prefix and/or suffix to each entry when the command line is produced, so SCons keeps them separate - appending a string will result in a separate string entry, not a combined string. For $CPPDEFINES. as well as $LIBS, and the various *PATH variables, SCons will amend the variable by supplying the compiler-specific syntax (e.g. prepending a -D or /D prefix for $CPPDEFINES), so you should omit this syntax when adding values to these variables. Examples (gcc syntax shown in the expansion of CPPDEFINES):

env = Environment(CXXFLAGS="-std=c11", CPPDEFINES="RELEASE")
print(f"CXXFLAGS = {env['CXXFLAGS']}, CPPDEFINES = {env['CPPDEFINES']}")
# notice including a leading space in CXXFLAGS addition
env.Append(CXXFLAGS=" -O", CPPDEFINES="EXTRA")
print(f"CXXFLAGS = {env['CXXFLAGS']}, CPPDEFINES = {env['CPPDEFINES']}")
print("CPPDEFINES will expand to", env.subst('$_CPPDEFFLAGS'))

$ scons -Q
CXXFLAGS = -std=c11, CPPDEFINES = RELEASE
CXXFLAGS = -std=c11 -O, CPPDEFINES = deque(['RELEASE', 'EXTRA'])
CPPDEFINES will expand to -DRELEASE -DEXTRA
scons: `.' is up to date.

Because $CPPDEFINES is intended for command-line specification of C/C++ preprocessor macros, additional syntax is accepted when adding to it. The preprocessor accepts arguments to predefine a macro name by itself (-DFOO for most compilers, /DFOO for Microsoft C++), which gives it an implicit value of 1, or can be given with a replacement value (-DBAR=TEXT). SCons follows these rules when adding to $CPPDEFINES:

• A string is split on spaces, giving an easy way to enter multiple macros in one addition. Use an = to specify a valued macro.
• A tuple is treated as a valued macro. Use the value None if the macro should not have a value. It is an error to supply more than two elements in such a tuple.
• A list is processed in order, adding each item without further interpretation. In this case, space-separated strings are not split.
• A dictionary is processed in order, adding each key-value pair as a valued macro. Use the value None if the macro should not have a value.

Examples:

env = Environment(CPPDEFINES="FOO")
print("CPPDEFINES =", env['CPPDEFINES'])
env.Append(CPPDEFINES="BAR=1")
print("CPPDEFINES =", env['CPPDEFINES'])
env.Append(CPPDEFINES=[("OTHER", 2)])
print("CPPDEFINES =", env['CPPDEFINES'])
env.Append(CPPDEFINES={"EXTRA": "arg"})
print("CPPDEFINES =", env['CPPDEFINES'])
print("CPPDEFINES will expand to", env.subst('$_CPPDEFFLAGS'))

$ scons -Q
CPPDEFINES = FOO
CPPDEFINES = deque(['FOO', 'BAR=1'])
CPPDEFINES = deque(['FOO', 'BAR=1', ('OTHER', 2)])
CPPDEFINES = deque(['FOO', 'BAR=1', ('OTHER', 2), ('EXTRA', 'arg')])
CPPDEFINES will expand to -DFOO -DBAR=1 -DOTHER=2 -DEXTRA=arg
scons: `.' is up to date.

Examples of adding multiple macros:

env = Environment()
env.Append(CPPDEFINES=[("ONE", 1), "TWO", ("THREE", )])
print("CPPDEFINES =", env['CPPDEFINES'])
env.Append(CPPDEFINES={"FOUR": 4, "FIVE": None})
print("CPPDEFINES =", env['CPPDEFINES'])
print("CPPDEFINES will expand to", env.subst('$_CPPDEFFLAGS'))

$ scons -Q
CPPDEFINES = [('ONE', 1), 'TWO', ('THREE',)]
CPPDEFINES = deque([('ONE', 1), 'TWO', ('THREE',), ('FOUR', 4), ('FIVE', None)])
CPPDEFINES will expand to -DONE=1 -DTWO -DTHREE -DFOUR=4 -DFIVE
scons: `.' is up to date.

Changed in version 4.5: clarified the use of tuples vs. other types, handling is now consistent across the four functions.

env = Environment()
env.Append(CPPDEFINES=("MACRO1", "MACRO2"))
print("CPPDEFINES =", env['CPPDEFINES'])
env.Append(CPPDEFINES=[("MACRO3", "MACRO4")])
print("CPPDEFINES =", env['CPPDEFINES'])
print("CPPDEFINES will expand to", env.subst('$_CPPDEFFLAGS'))

$ scons -Q
CPPDEFINES = ('MACRO1', 'MACRO2')
CPPDEFINES = deque(['MACRO1', 'MACRO2', ('MACRO3', 'MACRO4')])
CPPDEFINES will expand to -DMACRO1 -DMACRO2 -DMACRO3=MACRO4
scons: `.' is up to date.

See $CPPDEFINES for more details.

Appending a string val to a dictionary-typed construction variable enters val as the key in the dictionary, and None as its value. Using a tuple type to supply a key-value pair only works for the special case of $CPPDEFINES described above.

Although most combinations of types work without needing to know the details, some combinations do not make sense and Python raises an exception.

When using env.Append to modify construction variables which are path specifications (conventionally, the names of such end in PATH), it is recommended to add the values as a list of strings, even if you are only adding a single string. The same goes for adding library names to $LIBS.

env.Append(CPPPATH=["#/include"])

See also env.AppendUnique, env.Prepend and env.PrependUnique.

env.AppendENVPath(name, newpath, [envname, sep, delete_existing=False])

Append path elements specified by newpath to the given search path string or list name in mapping envname in the construction environment. Supplying envname is optional: the default is the execution environment $ENV. Optional sep is used as the search path separator, the default is the platform's separator (os.pathsep). A path element will only appear once. Any duplicates in newpath are dropped, keeping the last appearing (to preserve path order). If delete_existing is False (the default) any addition duplicating an existing path element is ignored; if delete_existing is True the existing value will be dropped and the path element will be added at the end. To help maintain uniqueness all paths are normalized (using os.path.normpath and os.path.normcase).

Example:

print('before:', env['ENV']['INCLUDE'])
include_path = '/foo/bar:/foo'
env.AppendENVPath('INCLUDE', include_path)
print('after:', env['ENV']['INCLUDE'])

Yields:

before: /foo:/biz
after: /biz:/foo/bar:/foo

See also env.PrependENVPath.

env.AppendUnique(key=val, [...], [delete_existing=False])

Append values to construction variables in the current construction environment, maintaining uniqueness. Works like env.Append, except that values that would become duplicates are not added. If delete_existing is set to a true value, then for any duplicate, the existing instance of val is first removed, then val is appended, having the effect of moving it to the end.

Example:

env.AppendUnique(CCFLAGS='-g', FOO=['foo.yyy'])

See also env.Append, env.Prepend and env.PrependUnique.

Builder(action, [arguments]), env.Builder(action, [arguments])

Creates a Builder object for the specified action. See the manpage section "Builder Objects" for a complete explanation of the arguments and behavior.

Note that the env.Builder() form of the invocation will expand construction variables in any arguments strings, including the action argument, at the time it is called using the construction variables in the env construction environment through which env.Builder was called. The Builder form delays all variable expansion until after the Builder object is actually called.

CacheDir(cache_dir, custom_class=None), env.CacheDir(cache_dir, custom_class=None)

Direct scons to maintain a derived-file cache in cache_dir. The derived files in the cache will be shared among all the builds specifying the same cache_dir. Specifying a cache_dir of None disables derived file caching.

Calling the environment method env.CacheDir limits the effect to targets built through the specified construction environment. Calling the global function CacheDir sets a global default that will be used by all targets built through construction environments that do not set up environment-specific caching by calling env.CacheDir.

Caching behavior can be configured by passing a specialized cache class as the optional custom_class parameter. This class must be a subclass of SCons.CacheDir.CacheDir. SCons will internally invoke the custom class for performing caching operations. If the parameter is omitted or set to None, SCons will use the default SCons.CacheDir.CacheDir class.

When derived-file caching is being used and scons finds a derived file that needs to be rebuilt, it will first look in the cache to see if a file with matching build signature exists (indicating the input file(s) and build action(s) were identical to those for the current target), and if so, will retrieve the file from the cache. scons will report Retrieved `file' from cache instead of the normal build message. If the derived file is not present in the cache, scons will build it and then place a copy of the built file in the cache, identified by its build signature, for future use.

The Retrieved `file' from cache messages are useful for human consumption, but less useful when comparing log files between scons runs which will show differences that are noisy and not actually significant. To disable, use the --cache-show option. With this option, scons changes printing to always show the action that would have been used to build the file without caching.

Derived-file caching may be disabled for any invocation of scons by giving the --cache-disable command line option; cache updating may be disabled, leaving cache fetching enabled, by giving the --cache-readonly option.

If the --cache-force option is used, scons will place a copy of all derived files into the cache, even if they already existed and were not built by this invocation. This is useful to populate a cache the first time a cache_dir is used for a build, or to bring a cache up to date after a build with cache updating disabled (--cache-disable or --cache-readonly) has been done.

The NoCache method can be used to disable caching of specific files. This can be useful if inputs and/or outputs of some tool are impossible to predict or prohibitively large.

Note that (at this time) SCons provides no facilities for managing the derived-file cache. It is up to the developer to arrange for cache pruning, expiry, access control, etc. if needed.

Clean(targets, files), env.Clean(targets, files)

Set additional files for removal when any of targets are selected for cleaning (-c command line option). targets and files can each be a single filename or node, or a list of filenames or nodes. These can refer to files or directories. Calling this method repeatedly has an additive effect.

The related NoClean method has higher priority: any target specified to NoClean will not be cleaned even if also given as a files parameter to Clean.

Examples:

Clean('foo', ['bar', 'baz'])
Clean('dist', env.Program('hello', 'hello.c'))
Clean(['foo', 'bar'], 'something_else_to_clean')

SCons does not directly track directories as targets - they are created if needed and not normally removed in clean mode. In this example, installing the project creates a subdirectory for the documentation. The Clean call ensures that the subdirectory is removed if the project is uninstalled.

Clean(docdir, os.path.join(docdir, projectname))

env.Clone([key=val, ...])

Returns an independent copy of a construction environment. If there are any unrecognized keyword arguments specified, they are added as construction variables in the copy, overwriting any existing values for those keywords. See the manpage section "Construction Environments" for more details.

Example:

env2 = env.Clone()
env3 = env.Clone(CCFLAGS='-g')

A list of tools and a toolpath may be specified, as in the Environment constructor:

def MyTool(env):
    env['FOO'] = 'bar'

env4 = env.Clone(tools=['msvc', MyTool])

The parse_flags keyword argument is also recognized, to allow merging command-line style arguments into the appropriate construction variables (see env.MergeFlags).

# create an environment for compiling programs that use wxWidgets
wx_env = env.Clone(parse_flags='!wx-config --cflags --cxxflags')

The variables keyword argument is also recognized, to allow (re)initializing construction variables from a Variables object.

Changed in version 4.8.0: the variables parameter was added.

Command(target, source, action, [key=val, ...]), env.Command(target, source, action, [key=val, ...])

Creates an anonymous builder and calls it, thus recording action to build target from source into the dependency tree. This can be more convenient for a single special-case build than having to define and add a new named Builder.

The Command function accepts the source_scanner and target_scanner keyword arguments which are used to specify custom scanners for the specified sources or targets. The value must be a Scanner object. For example, the global DirScanner object can be used if any of the sources will be directories that must be scanned on-disk for changes to files that aren't already specified in other Builder or function calls.

The Command function also accepts the source_factory and target_factory keyword arguments which are used to specify factory functions to create SCons Nodes from any sources or targets specified as strings. If any sources or targets are already Node objects, they are not further transformed even if a factory is specified for them. The default for each is the Entry factory.

These four arguments, if given, are used in the creation of the Builder. Other Builder-specific keyword arguments are not recognized as such. See the manpage section "Builder Objects" for more information about how these arguments work in a Builder.

Any remaining keyword arguments are passed on to the generated builder when it is called, and behave as described in the manpage section "Builder Methods", in short: recognized arguments have their specified meanings, while the rest are used to override any same-named existing construction variables from the construction environment.

action can be an external command, specified as a string, or a callable Python object; see the manpage section "Action Objects" for more complete information. Also note that a string specifying an external command may be preceded by an at-sign (@) to suppress printing the command in question, or by a hyphen (-) to ignore the exit status of the external command.

Examples:

env.Command(
    target='foo.out',
    source='foo.in',
    action="$FOO_BUILD < $SOURCES > $TARGET"
)

env.Command(
    target='bar.out',
    source='bar.in',
    action=["rm -f $TARGET", "$BAR_BUILD < $SOURCES > $TARGET"],
    ENV={'PATH': '/usr/local/bin/'},
)


import os
def rename(env, target, source):
    os.rename('.tmp', str(target[0]))


env.Command(
    target='baz.out',
    source='baz.in',
    action=["$BAZ_BUILD < $SOURCES > .tmp", rename],
)

Note that the Command function will usually assume, by default, that the specified targets and/or sources are Files, if no other part of the configuration identifies what type of entries they are. If necessary, you can explicitly specify that targets or source nodes should be treated as directories by using the Dir or env.Dir functions.

Examples:

env.Command('ddd.list', Dir('ddd'), 'ls -l $SOURCE > $TARGET')

env['DISTDIR'] = 'destination/directory'
env.Command(env.Dir('$DISTDIR')), None, make_distdir)

Also note that SCons will usually automatically create any directory necessary to hold a target file, so you normally don't need to create directories by hand.

Configure(env, [custom_tests, conf_dir, log_file, config_h]), env.Configure([custom_tests, conf_dir, log_file, config_h])

Creates a Configure object for integrated functionality similar to GNU autoconf. See the manpage section "Configure Contexts" for a complete explanation of the arguments and behavior.

DebugOptions([json])

Allows setting options for SCons debug options. Currently, the only supported value is json which sets the path to the JSON file created when --debug=json is set.

DebugOptions(json='#/build/output/scons_stats.json')

New in version 4.6.0.

Decider(function), env.Decider(function)

Specifies that all up-to-date decisions for targets built through this construction environment will be handled by function. function can be the name of a function or one of the following strings that specify a predefined decider function:

"content"

Specifies that a target shall be considered out-of-date and rebuilt if the dependency's content has changed since the last time the target was built, as determined by performing a checksum on the dependency's contents using the selected hash function, and comparing it to the checksum recorded the last time the target was built. content is the default decider.

Changed in version 4.1: The decider was renamed to content since the hash function is now selectable. The former name, MD5, can still be used as a synonym, but is deprecated.

"content-timestamp"

Specifies that a target shall be considered out-of-date and rebuilt if the dependency's content has changed since the last time the target was built, except that dependencies with a timestamp that matches the last time the target was rebuilt will be assumed to be up-to-date and not rebuilt. This provides behavior very similar to the content behavior of always checksumming file contents, with an optimization of not checking the contents of files whose timestamps haven't changed. The drawback is that SCons will not detect if a file's content has changed but its timestamp is the same, as might happen in an automated script that runs a build, updates a file, and runs the build again, all within a single second.

Changed in version 4.1: The decider was renamed to content-timestamp since the hash function is now selectable. The former name, MD5-timestamp, can still be used as a synonym, but is deprecated.

"timestamp-newer"

Specifies that a target shall be considered out-of-date and rebuilt if the dependency's timestamp is newer than the target file's timestamp. This is the behavior of the classic Make utility, and make can be used a synonym for timestamp-newer.

"timestamp-match"

Specifies that a target shall be considered out-of-date and rebuilt if the dependency's timestamp is different than the timestamp recorded the last time the target was built. This provides behavior very similar to the classic Make utility (in particular, files are not opened up so that their contents can be checksummed) except that the target will also be rebuilt if a dependency file has been restored to a version with an earlier timestamp, such as can happen when restoring files from backup archives.

Examples:

# Use exact timestamp matches by default.
Decider('timestamp-match')

# Use hash content signatures for any targets built
# with the attached construction environment.
env.Decider('content')

In addition to the above already-available functions, the function argument may be a Python function you supply. Such a function must accept the following four arguments:

dependency

The Node (file) which should cause the target to be rebuilt if it has "changed" since the last time target was built.

target

The Node (file) being built. In the normal case, this is what should get rebuilt if the dependency has "changed."

prev_ni

Stored information about the state of the dependency the last time the target was built. This can be consulted to match various file characteristics such as the timestamp, size, or content signature.

repo_node

If set, use this Node instead of the one specified by dependency to determine if the dependency has changed. This argument is optional so should be written as a default argument (typically it would be written as repo_node=None). A caller will normally only set this if the target only exists in a Repository.

The function should return a value which evaluates True if the dependency has "changed" since the last time the target was built (indicating that the target should be rebuilt), and a value which evaluates False otherwise (indicating that the target should not be rebuilt). Note that the decision can be made using whatever criteria are appropriate. Ignoring some or all of the function arguments is perfectly normal.

Example:

def my_decider(dependency, target, prev_ni, repo_node=None):
    return not os.path.exists(str(target))

env.Decider(my_decider)

Default(target[, ...]), env.Default(target[, ...])

Specify default targets to the SCons target selection mechanism. Any call to Default will cause SCons to use the defined default target list instead of its built-in algorithm for determining default targets (see the manpage section "Target Selection").

target may be one or more strings, a list of strings, a NodeList as returned by a Builder, or None. A string target may be the name of a file or directory, or a target previously defined by a call to Alias (defining the alias later will still create the alias, but it will not be recognized as a default). Calls to Default are additive. A target of None will clear any existing default target list; subsequent calls to Default will add to the (now empty) default target list like normal.

Both forms of this call affect the same global list of default targets; the construction environment method applies construction variable expansion to the targets.

The current list of targets added using Default is available in the DEFAULT_TARGETS list (see below).

Examples:

Default('foo', 'bar', 'baz')
env.Default(['a', 'b', 'c'])
hello = env.Program('hello', 'hello.c')
env.Default(hello)

DefaultEnvironment([key=value, ...])

Instantiates and returns the global construction environment object. The Default Environment is used internally by SCons when executing a global function or the global form of a Builder method that requires access to a construction environment.

On the first call, arguments are interpreted as for the Environment function. The Default Environment is a singleton; subsequent calls to DefaultEnvironment return the already-constructed object, and any keyword arguments are silently ignored.

The Default Environment can be modified after instantiation, similar to other construction environments, although some construction environment methods may be unavailable. Modifying the Default Environment has no effect on any other construction environment, either existing or newly constructed.

It is not necessary to explicitly call DefaultEnvironment. SCons instantiates the default environment automatically when the build phase begins, if has not already been done. However, calling it explicitly provides the opportunity to affect and examine its contents. Instantiation occurs even if nothing in the build system appears to use it, due to internal uses.

If the project SConscript files do not use global functions or Builders, a small performance gain may be achieved by calling DefaultEnvironment with an empty tools list (DefaultEnvironment(tools=[])). This avoids the tool initialization cost for the Default Environment, which is mainly of interest in the test suite where scons is launched repeatedly in a short time period.

Depends(target, dependency), env.Depends(target, dependency)

Specifies an explicit dependency; the target will be rebuilt whenever the dependency has changed. Both the specified target and dependency can be a string (usually the path name of a file or directory) or Node objects, or a list of strings or Node objects (such as returned by a Builder call). This should only be necessary for cases where the dependency is not caught by a Scanner for the file.

Example:

env.Depends('foo', 'other-input-file-for-foo')

mylib = env.Library('mylib.c')
installed_lib = env.Install('lib', mylib)
bar = env.Program('bar.c')

# Arrange for the library to be copied into the installation
# directory before trying to build the "bar" program.
# (Note that this is for example only.  A "real" library
# dependency would normally be configured through the $LIBS
# and $LIBPATH variables, not using an env.Depends() call.)

env.Depends(bar, installed_lib)

env.Detect(progs)

Find an executable from one or more choices: progs may be a string or a list of strings. Returns the first value from progs that was found, or None. Executable is searched by checking the paths in the execution environment (env['ENV']['PATH']). On Windows systems, additionally applies the filename suffixes found in the execution environment (env['ENV']['PATHEXT']) but will not include any such extension in the return value. env.Detect is a wrapper around env.WhereIs.

env.Dictionary([var, ...], [as_dict=])

Return an object containing construction variables from env. If var is omitted, all the construction variables with their values are returned in a dict. If var is specified, and as_dict is true, the specified construction variables are returned in a dict; otherwise (the default, for backwards compatibility), values only are returned, as a scalar if one var is given, or as a list if multiples.

Example:

cvars = env.Dictionary()
cc_values = env.Dictionary('CC', 'CCFLAGS', 'CCCOM')

Note
The object returned by env.Dictionary should be treated as a read-only view into the construction variables. Some construction variables require special internal handling, and modifying them through the env.Dictionary object can bypass that handling and cause data inconsistencies. The primary use of env.Dictionary is for diagnostic purposes - it is used widely by test cases specifically because it bypasses the special handling so that behavior can be verified.

Changed in 4.9.0: as_dict added.

Dir(name, [directory]), env.Dir(name, [directory])

Returns Directory Node(s). A Directory Node is an object that represents a directory. name can be a relative or absolute path or a list of such paths. directory is an optional directory that will be used as the parent directory. If no directory is specified, the current script's directory is used as the parent.

If name is a single pathname, the corresponding node is returned. If name is a list, SCons returns a list of nodes. Construction variables are expanded in name.

Directory Nodes can be used anywhere you would supply a string as a directory name to a Builder method or function. Directory Nodes have attributes and methods that are useful in many situations; see manpage section "Filesystem Nodes" for more information.

env.Dump([var, ...], [format=TYPE])

Serialize construction variables from env to a string. If var is omitted, all the construction variables are serialized. If one or more var values are supplied, only those variables and their values are serialized.

The optional format string selects the serialization format:

pretty

Returns a pretty-printed representation of the construction variables - the result will look like a Python dict (this is the default).

json

Returns a JSON-formatted representation of the variables. The variables will be presented as a JSON object literal, the JSON equivalent of a Python dict..

Changed in 4.9.0: More than one key can be specified. The returned string always looks like a dict (or equivalent in other formats); previously a single key serialized only the value, not the key with the value.

Examples: this SConstruct

env = Environment()
print(env.Dump('CCCOM'))
print(env.Dump('CC', 'CCFLAGS', format='json'))

will print something like:

{'CCCOM': '$CC -o $TARGET -c $CFLAGS $CCFLAGS $_CCCOMCOM $SOURCES'}
{
    "CC": "gcc",
    "CCFLAGS": []
}

While this SConstruct:

env = Environment()
print(env.Dump())

will print something like:

{ 'AR': 'ar',
  'ARCOM': '$AR $ARFLAGS $TARGET $SOURCES\n$RANLIB $RANLIBFLAGS $TARGET',
  'ARFLAGS': ['r'],
  'AS': 'as',
  'ASCOM': '$AS $ASFLAGS -o $TARGET $SOURCES',
  'ASFLAGS': [],
  ...

EnsurePythonVersion(major, minor)

Ensure that the Python version is at least major.minor. This function will print out an error message and exit SCons with a non-zero exit code if the actual Python version is not late enough.

Example:

EnsurePythonVersion(2,2)

EnsureSConsVersion(major, minor, [revision])

Ensure that the SCons version is at least major.minor, or major.minor.revision. if revision is specified. This function will print out an error message and exit SCons with a non-zero exit code if the actual SCons version is not late enough.

Examples:

EnsureSConsVersion(0,14)

EnsureSConsVersion(0,96,90)

Environment([key=value, ...]), env.Environment([key=value, ...])

Return a new construction environment initialized with the specified key=value pairs. The keyword arguments parse_flags, platform, toolpath, tools and variables are specially recognized and do not lead to construction variable creation. See the manpage section "Construction Environments" for more details.

Execute(action, [actionargs ...]), env.Execute(action, [actionargs ...])

Executes an Action. action may be an Action object or it may be a command-line string, list of commands, or executable Python function, each of which will first be converted into an Action object and then executed. Any additional arguments to Execute are passed on to the Action factory function which actually creates the Action object (see the manpage section Action Objects for a description). Example:

Execute(Copy('file.out', 'file.in'))

Execute performs its action immediately, as part of the SConscript-reading phase. There are no sources or targets declared in an Execute call, so any objects it manipulates will not be tracked as part of the SCons dependency graph. In the example above, neither file.out nor file.in will be tracked objects.

Execute returns the exit value of the command or return value of the Python function. scons prints an error message if the executed action fails (exits with or returns a non-zero value), however it does not, automatically terminate the build for such a failure. If you want the build to stop in response to a failed Execute call, you must explicitly check for a non-zero return value:

if Execute("mkdir sub/dir/ectory"):
    # The mkdir failed, don't try to build.
    Exit(1)

Exit([value])

This tells scons to exit immediately with the specified value. A default exit value of 0 (zero) is used if no value is specified.

Export([vars...], [key=value...]), env.Export([vars...], [key=value...])

Exports variables for sharing with other SConscript files. The variables are added to a global collection where they can be imported by other SConscript files. vars may be one or more strings, or a list of strings. If any string contains whitespace, it is split automatically into individual strings. Each string must match the name of a variable that is in scope during evaluation of the current SConscript file, or an exception is raised.

A vars argument may also be a dictionary or individual keyword arguments; in accordance with Python syntax rules, keyword arguments must come after any non-keyword arguments. The dictionary/keyword form can be used to map the local name of a variable to a different name to be used for imports. See the Examples for an illustration of the syntax.

Export calls are cumulative. Specifying a previously exported variable will replace the previous value in the collection. Both local variables and global variables can be exported.

To use an exported variable, an SConscript must call Import to bring it into its own scope. Importing creates an additional reference to the object that was originally exported, so if that object is mutable, changes made will be visible to other users of that object.

Examples:

env = Environment()
# Make env available for all SConscript files to Import().
Export("env")

package = 'my_name'
# Make env and package available for all SConscript files:.
Export("env", "package")

# Make env and package available for all SConscript files:
Export(["env", "package"])

# Make env available using the name debug:
Export(debug=env)

# Make env available using the name debug:
Export({"debug": env})

Note that the SConscript function also supports an exports argument that allows exporting one or more variables to the SConscript files invoked by that call (only). See the description of that function for details.

File(name, [directory]), env.File(name, [directory])

Returns File Node(s). A File Node is an object that represents a file. name can be a relative or absolute path or a list of such paths. directory is an optional directory that will be used as the parent directory. If no directory is specified, the current script's directory is used as the parent.

If name is a single pathname, the corresponding node is returned. If name is a list, SCons returns a list of nodes. Construction variables are expanded in name.

File Nodes can be used anywhere you would supply a string as a file name to a Builder method or function. File Nodes have attributes and methods that are useful in many situations; see manpage section "Filesystem Nodes" for more information.

FindFile(file, dirs), env.FindFile(file, dirs)

Search for file in the path specified by dirs. dirs may be a list of directory names or a single directory name. In addition to searching for files that exist in the filesystem, this function also searches for derived files that have not yet been built.

Example:

foo = env.FindFile('foo', ['dir1', 'dir2'])

FindInstalledFiles(), env.FindInstalledFiles()

Returns the list of targets set up by the Install or InstallAs builders.

This function serves as a convenient method to select the contents of a binary package.

Example:

Install('/bin', ['executable_a', 'executable_b'])

# will return the file node list
# ['/bin/executable_a', '/bin/executable_b']
FindInstalledFiles()

Install('/lib', ['some_library'])

# will return the file node list
# ['/bin/executable_a', '/bin/executable_b', '/lib/some_library']
FindInstalledFiles()

FindPathDirs(variable)

Returns a function (actually a callable Python object) intended to be used as the path_function of a Scanner object. The returned object will look up the specified variable in a construction environment and treat the construction variable's value as a list of directory paths that should be searched (like $CPPPATH, $LIBPATH, etc.).

Note that use of FindPathDirs is generally preferable to writing your own path_function for the following reasons: 1) The returned list will contain all appropriate directories found in source trees (when VariantDir is used) or in code repositories (when Repository or the -Y option are used). 2) scons will identify expansions of variable that evaluate to the same list of directories as, in fact, the same list, and avoid re-scanning the directories for files, when possible.

Example:

def my_scan(node, env, path, arg):
    # Code to scan file contents goes here...
    return include_files

scanner = Scanner(name = 'myscanner',
                  function = my_scan,
                  path_function = FindPathDirs('MYPATH'))

FindSourceFiles(node='"."'), env.FindSourceFiles(node='"."')

Returns the list of nodes which serve as the source of the built files. It does so by inspecting the dependency tree starting at the optional argument node which defaults to the '"."'-node. It will then return all leaves of node. These are all children which have no further children.

This function is a convenient method to select the contents of a Source Package.

Example:

Program('src/main_a.c')
Program('src/main_b.c')
Program('main_c.c')

# returns ['main_c.c', 'src/main_a.c', 'SConstruct', 'src/main_b.c']
FindSourceFiles()

# returns ['src/main_b.c', 'src/main_a.c' ]
FindSourceFiles('src')

As you can see, build support files (SConstruct in the above example) will also be returned by this function.

Flatten(sequence), env.Flatten(sequence)

Takes a sequence (that is, a Python list or tuple) that may contain nested sequences and returns a flattened list containing all of the individual elements in any sequence. This can be helpful for collecting the lists returned by calls to Builders; other Builders will automatically flatten lists specified as input, but direct Python manipulation of these lists does not.

Examples:

foo = Object('foo.c')
bar = Object('bar.c')

# Because `foo' and `bar' are lists returned by the Object() Builder,
# `objects' will be a list containing nested lists:
objects = ['f1.o', foo, 'f2.o', bar, 'f3.o']

# Passing such a list to another Builder is all right because
# the Builder will flatten the list automatically:
Program(source = objects)

# If you need to manipulate the list directly using Python, you need to
# call Flatten() yourself, or otherwise handle nested lists:
for object in Flatten(objects):
    print(str(object))

GetBuildFailures()

Returns a list of exceptions for the actions that failed while attempting to build targets. Each element in the returned list is a BuildError object with the following attributes that record various aspects of the build failure:

.node The node that was being built when the build failure occurred.

.status The numeric exit status returned by the command or Python function that failed when trying to build the specified Node.

.errstr The SCons error string describing the build failure. (This is often a generic message like "Error 2" to indicate that an executed command exited with a status of 2.)

.filename The name of the file or directory that actually caused the failure. This may be different from the .node attribute. For example, if an attempt to build a target named sub/dir/target fails because the sub/dir directory could not be created, then the .node attribute will be sub/dir/target but the .filename attribute will be sub/dir.

.executor The SCons Executor object for the target Node being built. This can be used to retrieve the construction environment used for the failed action.

.action The actual SCons Action object that failed. This will be one specific action out of the possible list of actions that would have been executed to build the target.

.command The actual expanded command that was executed and failed, after expansion of $TARGET, $SOURCE, and other construction variables.

Note that the GetBuildFailures function will always return an empty list until any build failure has occurred, which means that GetBuildFailures will always return an empty list while the SConscript files are being read. Its primary intended use is for functions that will be executed before SCons exits by passing them to the standard Python atexit.register() function. Example:

import atexit

def print_build_failures():
    from SCons.Script import GetBuildFailures
    for bf in GetBuildFailures():
        print("%s failed: %s" % (bf.node, bf.errstr))

atexit.register(print_build_failures)

GetBuildPath(file, [...]), env.GetBuildPath(file, [...])

Returns the scons path name (or names) for the specified file (or files). The specified file or files may be scons Nodes or strings representing path names.

GetLaunchDir()

Returns the absolute path name of the directory from which scons was initially invoked. This can be useful when using the -u, -U or -D options, which internally change to the directory in which the SConstruct file is found.

GetOption(name), env.GetOption(name)

Query the value of settable options which may have been set on the command line, via option defaults, or by using the SetOption function. The value of the option is returned in a type matching how the option was declared - see the documentation of the corresponding command line option for information about each specific option.

name can be an entry from the following table, which shows the corresponding command line arguments that could affect the value. name can be also be the destination variable name from a project-specific option added using the AddOption function, as long as that addition has been processed prior to the GetOption call in the SConscript files.

Query name	Command-line options	Notes
cache_debug	--cache-debug
cache_disable	--cache-disable,      --no-cache
cache_force	--cache-force,      --cache-populate
cache_readonly	--cache-readonly
cache_show	--cache-show
clean	-c,      --clean,      --remove
climb_up	-D      -U      -u      --up      --search_up
config	--config
debug	--debug
directory	-C, --directory
diskcheck	--diskcheck
duplicate	--duplicate
enable_virtualenv	--enable-virtualenv
experimental	--experimental	since 4.2
file	-f,      --file,      --makefile,      --sconstruct
hash_format	--hash-format	since 4.2
help	-h, --help
ignore_errors	-i, --ignore-errors
ignore_virtualenv	--ignore-virtualenv
implicit_cache	--implicit-cache
implicit_deps_changed	--implicit-deps-changed
implicit_deps_unchanged	--implicit-deps-unchanged
include_dir	-I, --include-dir
install_sandbox	--install-sandbox	Available only if the install tool has been called
keep_going	-k, --keep-going
max_drift	--max-drift
md5_chunksize	--hash-chunksize,      --md5-chunksize	--hash-chunksize since 4.2
no_exec	-n,      --no-exec,      --just-print,      --dry-run,      --recon
no_progress	-Q
num_jobs	-j, --jobs
package_type	--package-type	Available only if the packaging tool has been called
profile_file	--profile
question	-q, --question
random	--random
repository	-Y,      --repository,      --srcdir
silent	-s,      --silent,      --quiet
site_dir	--site-dir, --no-site-dir
stack_size	--stack-size
taskmastertrace_file	--taskmastertrace
tree_printers	--tree
warn	--warn, --warning

GetSConsVersion()

Returns the current SCons version in the form of a Tuple[int, int, int], representing the major, minor, and revision values respectively. Added in 4.8.0.

Glob(pattern, [ondisk=True, source=False, strings=False, exclude=None]), env.Glob(pattern, [ondisk=True, source=False, strings=False, exclude=None])

Returns a possibly empty list of Nodes (or strings) that match pathname specification pattern. pattern can be absolute, top-relative, or (most commonly) relative to the directory of the current SConscript file. Glob matches both files stored on disk and Nodes which SCons already knows about, even if any corresponding file is not currently stored on disk. The environment method form (env.Glob) performs string substitution on pattern and returns whatever matches the resulting expanded pattern. The results are sorted, unlike for the similar Python glob.glob function, to ensure build order will be stable.

pattern can contain POSIX-style shell metacharacters for matching:

Pattern	Meaning
*	matches everything
?	matches any single character
[seq]	matches any character in seq      (can be a list or a range).
[!seq]	matches any character not in seq

For a literal match, wrap the metacharacter in brackets to escape the normal behavior. For example, '[?]' matches the character '?'.

Filenames starting with a dot are specially handled - they can only be matched by patterns that start with a dot (or have a dot immediately following a pathname separator character, or slash), they are not not matched by the metacharacters. Metacharacter matches also do not span directory separators.

Glob understands repositories (see the Repository function) and source directories (see the VariantDir function) and returns a Node (or string, if so configured) match in the local (SConscript) directory if a matching Node is found anywhere in a corresponding repository or source directory.

If the optional ondisk argument evaluates false, the search for matches on disk is disabled, and only matches from already-configured File or Dir Nodes are returned. The default is to return Nodes for matches on disk as well.

If the optional source argument evaluates true, and the local directory is a variant directory, then Glob returns Nodes from the corresponding source directory, rather than the local directory.

If the optional strings argument evaluates true, Glob returns matches as strings, rather than Nodes. The returned strings will be relative to the local (SConscript) directory. (Note that while this may make it easier to perform arbitrary manipulation of file names, it loses the context SCons would have in the Node, so if the returned strings are passed to a different SConscript file, any Node translation there will be relative to that SConscript directory, not to the original SConscript directory.)

The optional exclude argument may be set to a pattern or a list of patterns describing files or directories to filter out of the match list. Elements matching a least one specified pattern will be excluded. These patterns use the same syntax as for pattern.

Examples:

Program("foo", Glob("*.c"))
Zip("/tmp/everything", Glob(".??*") + Glob("*"))
sources = Glob("*.cpp", exclude=["os_*_specific_*.cpp"]) \
    + Glob("os_%s_specific_*.cpp" % currentOS)

Help(text, append=False, local_only=False), env.Help(text, append=False, local_only=False)

Adds text to the help message shown when scons is called with the -h or --help argument.

On the first call to Help, if append is False (the default), any existing help text is discarded. The default help text is the help for the scons command itself plus help collected from any project-local AddOption calls. This is the help printed if Help has never been called. If append is True, text is appended to the existing help text. If local_only is also True (the default is False), the project-local help from AddOption calls is preserved in the help message but the scons command help is not.

Subsequent calls to Help ignore the keyword arguments append and local_only and always append to the existing help text.

Changed in 4.6.0: added local_only.

Ignore(target, dependency), env.Ignore(target, dependency)

Ignores dependency when deciding if target needs to be rebuilt. target and dependency can each be a single filename or Node or a list of filenames or Nodes.

Ignore can also be used to remove a target from the default build by specifying the directory the target will be built in as target and the file you want to skip selecting for building as dependency. Note that this only removes the target from the default target selection algorithm: if it is a dependency of another object being built SCons still builds it normally. See the third and forth examples below.

Examples:

env.Ignore('foo', 'foo.c')
env.Ignore('bar', ['bar1.h', 'bar2.h'])
env.Ignore('.', 'foobar.obj')
env.Ignore('bar', 'bar/foobar.obj')

Import(vars...), env.Import(vars...)

Imports variables into the scope of the current SConscript file. vars must be strings representing names of variables which have been previously exported either by the Export function or by the exports argument to the SConscript function. Variables exported by the SConscript call take precedence. Multiple variable names can be passed to Import as separate arguments, as a list of strings, or as words in a space-separated string. The wildcard "*" can be used to import all available variables.

If the imported variable is mutable, changes made locally will be reflected in the object the variable is bound to. This allows subsidiary SConscript files to contribute to building up, for example, a construction environment.

Examples:

Import("env")
Import("env", "variable")
Import(["env", "variable"])
Import("*")

Literal(string), env.Literal(string)

The specified string will be preserved as-is and not have construction variables expanded.

Local(targets), env.Local(targets)

The specified targets will have copies made in the local tree, even if an already up-to-date copy exists in a repository. Returns a list of the target Node or Nodes.

env.MergeFlags(arg, [unique])

Merges values from arg into construction variables in env. If arg is a dictionary, each key-value pair represents a construction variable name and the corresponding flags to merge. If arg is not a dictionary, MergeFlags attempts to convert it to one before the values are merged. env.ParseFlags is used for this, so values to be converted are subject to the same limitations: ParseFlags has knowledge of which construction variables certain flags should go to, but not all; and only for GCC and compatible compiler chains. arg must be a single object, so to pass multiple strings, enclose them in a list.

If unique is true (the default), duplicate values are not retained. In case of duplication, any construction variable names that end in PATH keep the left-most value so the path search order is not altered. All other construction variables keep the right-most value. If unique is false, values are appended even if they are duplicates.

Examples:

# Add an optimization flag to $CCFLAGS.
env.MergeFlags({'CCFLAGS': '-O3'})

# Combine the flags returned from running pkg-config with an optimization
# flag and merge the result into the construction variables.
env.MergeFlags(['!pkg-config gtk+-2.0 --cflags', '-O3'])

# Combine an optimization flag with the flags returned from running pkg-config
# for two distinct packages and merge into the construction variables.
env.MergeFlags(
    [
        '-O3',
        '!pkg-config gtk+-2.0 --cflags --libs',
        '!pkg-config libpng12 --cflags --libs',
    ]
)

NoCache(target, ...), env.NoCache(target, ...)

Specifies a list of files which should not be cached whenever the CacheDir method has been activated. The specified targets may be a list or an individual target.

Multiple files should be specified either as separate arguments to the NoCache method, or as a list. NoCache will also accept the return value of any of the construction environment Builder methods.

Calling NoCache on directories and other non-File Node types has no effect because only File Nodes are cached.

Examples:

NoCache('foo.elf')
NoCache(env.Program('hello', 'hello.c'))

NoClean(targets, ...), env.NoClean(targets, ...)

Specifies files or directories which should not be removed whenever a specified target (or its dependencies) is selected and clean mode is active (-c command line option). targets may be one or more file or directory names or nodes, and/or lists of names or nodes. NoClean can be called multiple times.

Calling NoClean for a target overrides calling Clean for the same target, so any targets passed to both functions will not be removed in clean mode.

Examples:

NoClean('foo.elf')
NoClean(env.Program('hello', 'hello.c'))

env.ParseConfig(command, [function, unique])

Updates the current construction environment with the values extracted from the output of running external command, by passing it to a helper function. command may be a string or a list of strings representing the command and its arguments. If function is omitted or None, env.MergeFlags is used. By default, duplicate values are not added to any construction variables; you can specify unique=False to allow duplicate values to be added.

command is executed using the SCons execution environment (that is, the construction variable $ENV in the current construction environment). If command needs additional information to operate properly, that needs to be set in the execution environment. For example, pkg-config may need a custom value set in the PKG_CONFIG_PATH environment variable.

env.MergeFlags needs to understand the output produced by command in order to distribute it to appropriate construction variables. env.MergeFlags uses a separate function to do that processing - see env.ParseFlags for the details, including a table of options and corresponding construction variables. To provide alternative processing of the output of command, you can supply a custom function, which must accept three arguments: the construction environment to modify, a string argument containing the output from running command, and the optional unique flag.

ParseDepends(filename, [must_exist, only_one]), env.ParseDepends(filename, [must_exist, only_one])

Parses the contents of filename as a list of dependencies in the style of Make or mkdep, and explicitly establishes all of the listed dependencies.

By default, it is not an error if filename does not exist. The optional must_exist argument may be set to True to have SCons raise an exception if the file does not exist, or is otherwise inaccessible.

The optional only_one argument may be set to True to have SCons raise an exception if the file contains dependency information for more than one target. This can provide a small sanity check for files intended to be generated by, for example, the gcc -M flag, which should typically only write dependency information for one output file into a corresponding .d file.

filename and all of the files listed therein will be interpreted relative to the directory of the SConscript file which calls the ParseDepends function.

env.ParseFlags(flags, ...)

Parses one or more strings containing typical command-line flags for GCC-style tool chains and returns a dictionary with the flag values separated into the appropriate SCons construction variables. Intended as a companion to the env.MergeFlags method, but allows for the values in the returned dictionary to be modified, if necessary, before merging them into the construction environment. (Note that env.MergeFlags will call this method if its argument is not a dictionary, so it is usually not necessary to call env.ParseFlags directly unless you want to manipulate the values.)

If the first character in any string is an exclamation mark (!), the rest of the string is executed as a command, and the output from the command is parsed as GCC tool chain command-line flags and added to the resulting dictionary. This can be used to call a *-config command typical of the POSIX programming environment (for example, pkg-config). Note that such a command is executed using the SCons execution environment; if the command needs additional information, that information needs to be explicitly provided. See ParseConfig for more details.

Flag values are translated according to the prefix found, and added to the following construction variables:

-arch                   CCFLAGS, LINKFLAGS
-D                      CPPDEFINES
-framework              FRAMEWORKS
-frameworkdir=          FRAMEWORKPATH
-fmerge-all-constants   CCFLAGS, LINKFLAGS
-fopenmp                CCFLAGS, LINKFLAGS
-fsanitize              CCFLAGS, LINKFLAGS
-include                CCFLAGS
-imacros                CCFLAGS
-isysroot               CCFLAGS, LINKFLAGS
-isystem                CCFLAGS
-iquote                 CCFLAGS
-idirafter              CCFLAGS
-I                      CPPPATH
-l                      LIBS
-L                      LIBPATH
-mno-cygwin             CCFLAGS, LINKFLAGS
-mwindows               LINKFLAGS
-openmp                 CCFLAGS, LINKFLAGS
-pthread                CCFLAGS, LINKFLAGS
-std=                   CFLAGS
-stdlib=                CXXFLAGS
-Wa,                    ASFLAGS, CCFLAGS
-Wl,-rpath=             RPATH
-Wl,-R,                 RPATH
-Wl,-R                  RPATH
-Wl,                    LINKFLAGS
-Wp,                    CPPFLAGS
-                       CCFLAGS
+                       CCFLAGS, LINKFLAGS

Any other strings not associated with options are assumed to be the names of libraries and added to the $LIBS construction variable.

Examples (all of which produce the same result):

dict = env.ParseFlags('-O2 -Dfoo -Dbar=1')
dict = env.ParseFlags('-O2', '-Dfoo', '-Dbar=1')
dict = env.ParseFlags(['-O2', '-Dfoo -Dbar=1'])
dict = env.ParseFlags('-O2', '!echo -Dfoo -Dbar=1')

Platform(plat), env.Platform(plat)

When called as a global function, returns a callable platform object selected by plat (defaults to the detected platform for the current system) that can be used to initialize a construction environment by passing it as the platform keyword argument to the Environment function.

Example:

env = Environment(platform=Platform('win32'))

When called as a method of an environment, calls the platform object indicated by plat to update that environment.

env.Platform('posix')

See the manpage section "Construction Environments" for more details.

Precious(target, ...), env.Precious(target, ...)

Marks target as precious so it is not deleted before it is rebuilt. Normally SCons deletes a target before building it. Multiple targets can be passed in a single call, and may be strings and/or nodes. Returns a list of the affected target nodes.

env.Prepend(key=val, [...])

Prepend values to construction variables in the current construction environment, works like env.Append (see for details), except that values are added to the front, rather than the end, of any existing value of the construction variable

Example:

env.Prepend(CCFLAGS='-g ', FOO=['foo.yyy'])

See also env.Append, env.AppendUnique and env.PrependUnique.

env.PrependENVPath(name, newpath, [envname, sep, delete_existing=True])

Prepend path elements specified by newpath to the given search path string or list name in mapping envname in the construction environment. Supplying envname is optional: the default is the execution environment $ENV. Optional sep is used as the search path separator, the default is the platform's separator (os.pathsep). A path element will only appear once. Any duplicates in newpath are dropped, keeping the first appearing (to preserve path order). If delete_existing is False any addition duplicating an existing path element is ignored; if delete_existing is True (the default) the existing value will be dropped and the path element will be inserted at the beginning. To help maintain uniqueness all paths are normalized (using os.path.normpath and os.path.normcase).

Example:

print('before:', env['ENV']['INCLUDE'])
include_path = '/foo/bar:/foo'
env.PrependENVPath('INCLUDE', include_path)
print('after:', env['ENV']['INCLUDE'])

Yields:

before: /biz:/foo
after: /foo/bar:/foo:/biz

See also env.AppendENVPath.

env.PrependUnique(key=val, [...], [delete_existing=False])

Prepend values to construction variables in the current construction environment, maintaining uniqueness. Works like env.Append, except that values are added to the front, rather than the end, of the construction variable, and values that would become duplicates are not added. If delete_existing is set to a true value, then for any duplicate, the existing instance of val is first removed, then val is inserted, having the effect of moving it to the front.

Example:

env.PrependUnique(CCFLAGS='-g', FOO=['foo.yyy'])

See also env.Append, env.AppendUnique and env.Prepend.

Progress(callable, [interval]), Progress(string, [interval, file, overwrite]), Progress(list_of_strings, [interval, file, overwrite])

Allows SCons to show progress made during the build by displaying a string or calling a function while evaluating Nodes (e.g. files).

If the first specified argument is a Python callable (a function or an object that has a __call__ method), the function will be called once every interval times a Node is evaluated (default 1). The callable will be passed the evaluated Node as its only argument. (For future compatibility, it's a good idea to also add *args and **kwargs as arguments to your function or method signatures. This will prevent the code from breaking if SCons ever changes the interface to call the function with additional arguments in the future.)

An example of a simple custom progress function that prints a string containing the Node name every 10 Nodes:

def my_progress_function(node, *args, **kwargs):
    print('Evaluating node %s!' % node)
Progress(my_progress_function, interval=10)

A more complicated example of a custom progress display object that prints a string containing a count every 100 evaluated Nodes. Note the use of \r (a carriage return) at the end so that the string will overwrite itself on a display:

import sys
class ProgressCounter(object):
    count = 0
    def __call__(self, node, *args, **kw):
        self.count += 100
        sys.stderr.write('Evaluated %s nodes\r' % self.count)

Progress(ProgressCounter(), interval=100)

If the first argument to Progress is a string or list of strings, it is taken as text to be displayed every interval evaluated Nodes. If the first argument is a list of strings, then each string in the list will be displayed in rotating fashion every interval evaluated Nodes.

The default is to print the string on standard output. An alternate output stream may be specified with the file keyword argument, which the caller must pass already opened.

The following will print a series of dots on the error output, one dot for every 100 evaluated Nodes:

import sys
Progress('.', interval=100, file=sys.stderr)

If the string contains the verbatim substring $TARGET;, it will be replaced with the Node. Note that, for performance reasons, this is not a regular SCons variable substitution, so you can not use other variables or use curly braces. The following example will print the name of every evaluated Node, using a carriage return) (\r) to cause each line to overwritten by the next line, and the overwrite keyword argument (default False) to make sure the previously-printed file name is overwritten with blank spaces:

import sys
Progress('$TARGET\r', overwrite=True)

A list of strings can be used to implement a "spinner" on the user's screen as follows, changing every five evaluated Nodes:

Progress(['-\r', '\\\r', '|\r', '/\r'], interval=5)

Pseudo(target, ...), env.Pseudo(target, ...)

Marks target as a pseudo target, not representing the production of any physical target file. If any pseudo target does exist, SCons will abort the build with an error. Multiple targets can be passed in a single call, and may be strings and/or Nodes. Returns a list of the affected target nodes.

Pseudo may be useful in conjuction with a builder call (such as Command) which does not create a physical target, and the behavior if the target accidentally existed would be incorrect. This is similar in concept to the GNU make .PHONY target. SCons also provides a powerful target alias capability (see Alias) which may provide more flexibility in many situations when defining target names that are not directly built.

PyPackageDir(modulename), env.PyPackageDir(modulename)

Finds the location of modulename, which can be a string or a sequence of strings, each representing the name of a Python module. Construction variables are expanded in modulename. Returns a Directory Node (see Dir), or a list of Directory Nodes if modulename is a sequence. None is returned for any module not found.

When a Tool module which is installed as a Python module is used, you need to specify a toolpath argument to Tool, Environment or Clone, as tools outside the standard project locations (site_scons/site_tools) will not be found otherwise. Using PyPackageDir allows this path to be discovered at runtime instead of hardcoding the path.

Example:

env = Environment(
    tools=["default", "ExampleTool"],
    toolpath=[PyPackageDir("example_tool")]
)

env.Replace(key=val, [...])

Replaces construction variables in the Environment with the specified keyword arguments.

Example:

env.Replace(CCFLAGS='-g', FOO='foo.xxx')

Repository(directory), env.Repository(directory)

Sets directory as a repository to be searched for files contributing to the build. Multiple calls to Repository are allowed, with repositories searched in the given order. Repositories specified via command-line option have higher priority.

In scons, a repository is partial or complete copy of the source tree, from the top-level directory down, containing source files that can be used to build targets in the current worktree. Repositories can also contain derived files. An example might be an official source tree maintained by an integrator. If a repository contains derived files, they should be the result of building with SCons, so a signature database (sconsign) is present in the repository, allowing better decisions on whether they are up-to-date or not.

Note that if an up-to-date derived file already exists in a repository, scons will not make a copy in the local directory tree. If you need a local copy to be made, use the Local method.

Requires(target, prerequisite), env.Requires(target, prerequisite)

Specifies an order-only relationship between target and prerequisite. The prerequisites will be (re)built, if necessary, before the target file(s), but the target file(s) do not actually depend on the prerequisites and will not be rebuilt simply because the prerequisite file(s) change. target and prerequisite may each be a string or Node, or a list of strings or Nodes. If there are multiple target values, the prerequisite(s) are added to each one. Returns a list of the affected target nodes.

Example:

env.Requires('foo', 'file-that-must-be-built-before-foo')

Return([vars..., stop=True])

Return to the calling SConscript, optionally returning the values of variables named in vars. Multiple strings containing variable names may be passed to Return. A string containing white space is split into individual variable names. Returns the value if one variable is specified, else returns a tuple of values. Returns an empty tuple if vars is omitted.

By default Return stops processing the current SConscript and returns immediately. The optional stop keyword argument may be set to a false value to continue processing the rest of the SConscript file after the Return call (this was the default behavior prior to SCons 0.98.) However, the values returned are still the values of the variables in the named vars at the point Return was called.

Examples:

# Returns no values (evaluates False)
Return()

# Returns the value of the 'foo' Python variable.
Return("foo")

# Returns the values of the Python variables 'foo' and 'bar'.
Return("foo", "bar")

# Returns the values of Python variables 'val1' and 'val2'.
Return('val1 val2')

Scanner(function, [name, argument, skeys, path_function, node_class, node_factory, scan_check, recursive]), env.Scanner(function, [name, argument, skeys, path_function, node_class, node_factory, scan_check, recursive])

Creates a Scanner object for the specified function. See manpage section "Scanner Objects" for a complete explanation of the arguments and behavior.

SConscript(scriptnames, [exports, variant_dir, duplicate, must_exist]), env.SConscript(scriptnames, [exports, variant_dir, duplicate, must_exist]), SConscript(dirs=subdirs, [name=scriptname, exports, variant_dir, duplicate, must_exist]), env.SConscript(dirs=subdirs, [name=scriptname, exports, variant_dir, duplicate, must_exist])

Executes subsidiary SConscript (build configuration) file(s). There are two ways to call the SConscript function.

The first calling style is to supply one or more SConscript file names as the first positional argument, which can be a string or a list of strings. If there is a second positional argument, it is treated as if the exports keyword argument had been given (see below). Examples:

SConscript('SConscript')  # run SConscript in the current directory
SConscript('src/SConscript')  # run SConscript in the src directory
SConscript(['src/SConscript', 'doc/SConscript'])
SConscript(Split('src/SConscript doc/SConscript'))
config = SConscript('MyConfig.py')

The second calling style is to omit the positional argument naming the script and instead specify directory names using the dirs keyword argument. The value can be a string or list of strings. In this case, scons will execute a subsidiary configuration file named SConscript (by default) in each of the specified directories. You may specify a name other than SConscript by supplying an optional name=scriptname keyword argument. The first three examples below have the same effect as the first three examples above:

SConscript(dirs='.')  # run SConscript in the current directory
SConscript(dirs='src')  # run SConscript in the src directory
SConscript(dirs=['src', 'doc'])
SConscript(dirs=['sub1', 'sub2'], name='MySConscript')

The optional exports keyword argument specifies variables to make available for use by the called SConscripts, which are evaluated in an isolated context and otherwise do not have access to local variables from the calling SConscript. The value may be a string or list of strings representing variable names, or a dictionary mapping local names to the names they can be imported by. For the first (scriptnames) calling style, a second positional argument will also be interpreted as exports; the second (directory) calling style accepts no positional arguments and must use the keyword form. These variables are locally exported only to the called SConscript file(s), and take precedence over any same-named variables in the global pool managed by the Export function. The subsidiary SConscript files must use the Import function to import the variables into their local scope. Examples:

foo = SConscript('sub/SConscript', exports='env')
SConscript('dir/SConscript', exports=['env', 'variable'])
SConscript(dirs='subdir', exports='env variable')
SConscript(dirs=['one', 'two', 'three'], exports='shared_info')

If the optional variant_dir argument is present, it causes an effect equivalent to the VariantDir function, but in effect only within the scope of the SConscript call. The variant_dir argument is interpreted relative to the directory of the calling SConscript file. The source directory is the directory in which the called SConscript file resides and the SConscript file is evaluated as if it were in the variant_dir directory. Thus:

SConscript('src/SConscript', variant_dir='build')

is equivalent to:

VariantDir('build', 'src')
SConscript('build/SConscript')

If the sources are in the same directory as the SConstruct,

SConscript('SConscript', variant_dir='build')

is equivalent to:

VariantDir('build', '.')
SConscript('build/SConscript')

The optional duplicate argument is interpreted as for VariantDir. If the variant_dir argument is omitted, the duplicate argument is ignored. See the description of VariantDir for additional details and restrictions.

If the optional must_exist is True (the default), an exception is raised if a requested SConscript file is not found. To allow missing scripts to be silently ignored (the default behavior prior to SCons version 3.1), pass must_exist=False in the SConscript call.

Changed in 4.6.0: must_exist now defaults to True.

Here are some composite examples:

# collect the configuration information and use it to build src and doc
shared_info = SConscript('MyConfig.py')
SConscript('src/SConscript', exports='shared_info')
SConscript('doc/SConscript', exports='shared_info')

# build debugging and production versions.  SConscript
# can use Dir('.').path to determine variant.
SConscript('SConscript', variant_dir='debug', duplicate=0)
SConscript('SConscript', variant_dir='prod', duplicate=0)

# build debugging and production versions.  SConscript
# is passed flags to use.
opts = { 'CPPDEFINES' : ['DEBUG'], 'CCFLAGS' : '-pgdb' }
SConscript('SConscript', variant_dir='debug', duplicate=0, exports=opts)
opts = { 'CPPDEFINES' : ['NODEBUG'], 'CCFLAGS' : '-O' }
SConscript('SConscript', variant_dir='prod', duplicate=0, exports=opts)

# build common documentation and compile for different architectures
SConscript('doc/SConscript', variant_dir='build/doc', duplicate=0)
SConscript('src/SConscript', variant_dir='build/x86', duplicate=0)
SConscript('src/SConscript', variant_dir='build/ppc', duplicate=0)

SConscript returns the values of any variables named by the executed SConscript file(s) in arguments to the Return function. If a single SConscript call causes multiple scripts to be executed, the return value is a tuple containing the returns of each of the scripts. If an executed script does not explicitly call Return, it returns None.

SConscriptChdir(value)

By default, scons changes its working directory to the directory in which each subsidiary SConscript file lives while reading and processing that script. This behavior may be disabled by specifying an argument which evaluates false, in which case scons will stay in the top-level directory while reading all SConscript files. (This may be necessary when building from repositories, when all the directories in which SConscript files may be found don't necessarily exist locally.) You may enable and disable this ability by calling SConscriptChdir multiple times.

Example:

SConscriptChdir(False)
SConscript('foo/SConscript')	# will not chdir to foo
SConscriptChdir(True)
SConscript('bar/SConscript')	# will chdir to bar

SConsignFile([name, dbm_module]), env.SConsignFile([name, dbm_module])

Specify where to store the SCons file signature database, and which database format to use. This may be useful to specify alternate database files and/or file locations for different types of builds.

The optional name argument is the base name of the database file(s). If not an absolute path name, these are placed relative to the directory containing the top-level SConstruct file. The default is .sconsign. The actual database file(s) stored on disk may have an appropriate suffix appended by the chosen dbm_module

The optional dbm_module argument specifies which Python database module to use for reading/writing the file. The module must be imported first; then the imported module name is passed as the argument. The default is a custom SCons.dblite module that uses pickled Python data structures, which works on all Python versions. See documentation of the Python dbm module for other available types.

If called with no arguments, the database will default to .sconsign.dblite in the top directory of the project, which is also the default if if SConsignFile is not called.

The setting is global, so the only difference between the global function and the environment method form is variable expansion on name. There should only be one active call to this function/method in a given build setup.

If name is set to None, scons will store file signatures in a separate .sconsign file in each directory, not in a single combined database file. This is a backwards-compatibility measure to support what was the default behavior prior to SCons 0.97 (i.e. before 2008). Use of this mode is discouraged and may be deprecated in a future SCons release.

Examples:

# Explicitly stores signatures in ".sconsign.dblite"
# in the top-level SConstruct directory (the default behavior).
SConsignFile()

# Stores signatures in the file "etc/scons-signatures"
# relative to the top-level SConstruct directory.
# SCons will add a database suffix to this name.
SConsignFile("etc/scons-signatures")

# Stores signatures in the specified absolute file name.
# SCons will add a database suffix to this name.
SConsignFile("/home/me/SCons/signatures")

# Stores signatures in a separate .sconsign file
# in each directory.
SConsignFile(None)

# Stores signatures in a GNU dbm format .sconsign file
import dbm.gnu
SConsignFile(dbm_module=dbm.gnu)

env.SetDefault(key=val, [...])

Sets construction variables to default values specified with the keyword arguments if (and only if) the variables are not already set. The following statements are equivalent:

env.SetDefault(FOO='foo')
if 'FOO' not in env:
    env['FOO'] = 'foo'

SetOption(name, value), env.SetOption(name, value)

Sets scons option variable name to value. These options are all also settable via command-line options but the variable name may differ from the command-line option name - see the table for correspondences. A value set via command-line option will take precedence over one set with SetOption, which allows setting a project default in the scripts and temporarily overriding it via command line. SetOption calls can also be placed in the site_init.py file.

See the documentation in the manpage for the corresponding command line option for information about each specific option. The value parameter is mandatory, for option values which are boolean in nature (that is, the command line option does not take an argument) use a value which evaluates to true (e.g. True, 1) or false (e.g. False, 0).

Options which affect the reading and processing of SConscript files are not settable using SetOption since those files must be read in order to find the SetOption call in the first place.

For project-specific options (sometimes called local options) added via an AddOption call, SetOption is available only after the AddOption call has completed successfully, and only if that call included the settable=True argument.

The settable variables with their associated command-line options are:

Settable name	Command-line options	Notes
clean	-c,    --clean,    --remove
diskcheck	--diskcheck
duplicate	--duplicate
experimental	--experimental	since 4.2
hash_chunksize	--hash-chunksize	Actually sets md5_chunksize.    since 4.2
hash_format	--hash-format	since 4.2
help	-h, --help
implicit_cache	--implicit-cache
implicit_deps_changed	--implicit-deps-changed	Also sets implicit_cache.    (settable since 4.2)
implicit_deps_unchanged	--implicit-deps-unchanged	Also sets implicit_cache.    (settable since 4.2)
max_drift	--max-drift
md5_chunksize	--md5-chunksize
no_exec	-n,    --no-exec,    --just-print,    --dry-run,    --recon
no_progress	-Q	See    [7]
num_jobs	-j, --jobs
random	--random
silent	-s,    --silent,    --quiet
stack_size	--stack-size
warn	--warn
---- [a] If no_progress is set via SetOption in an SConscript file (but not if set in a site_init.py file) there will still be an initial status message about reading SConscript files since SCons has to start reading them before it can see the SetOption.

Example:

SetOption('max_drift', 0)

SideEffect(side_effect, target), env.SideEffect(side_effect, target)

Declares side_effect as a side effect of building target. Both side_effect and target can be a list, a file name, or a node. A side effect is a target file that is created or updated as a side effect of building other targets. For example, a Windows PDB file is created as a side effect of building the .obj files for a static library, and various log files are created updated as side effects of various TeX commands. If a target is a side effect of multiple build commands, scons will ensure that only one set of commands is executed at a time. Consequently, you only need to use this method for side-effect targets that are built as a result of multiple build commands.

Because multiple build commands may update the same side effect file, by default the side_effect target is not automatically removed when the target is removed by the -c option. (Note, however, that the side_effect might be removed as part of cleaning the directory in which it lives.) If you want to make sure the side_effect is cleaned whenever a specific target is cleaned, you must specify this explicitly with the Clean or env.Clean function.

This function returns the list of side effect Node objects that were successfully added. If the list of side effects contained any side effects that had already been added, they are not added and included in the returned list.

Split(arg), env.Split(arg)

If arg is a string, splits on whitespace and returns a list of strings without whitespace. This mode is the most common case, and can be used to split a list of filenames (for example) rather than having to type them as a list of individually quoted words. If arg is a list or tuple returns the list or tuple unchanged. If arg is any other type of object, returns a list containing just the object. These non-string cases do not actually do any spliting, but allow an argument variable to be passed to Split without having to first check its type.

Example:

files = Split("f1.c f2.c f3.c")
files = env.Split("f4.c f5.c f6.c")
files = Split("""
    f7.c
    f8.c
    f9.c
""")

env.subst(input, [raw, target, source, conv])

Performs construction variable interpolation (substitution) on input, which can be a string or a sequence. Substitutable elements take the form ${expression}, although if there is no ambiguity in recognizing the element, the braces can be omitted. A literal $ can be entered by using $$.

By default, leading or trailing white space will be removed from the result, and all sequences of white space will be compressed to a single space character. Additionally, any $( and $) character sequences will be stripped from the returned string, The optional raw argument may be set to 1 if you want to preserve white space and $(-$) sequences. The raw argument may be set to 2 if you want to additionally discard all characters between any $( and $) pairs (as is done for signature calculation).

If input is a sequence (list or tuple), the individual elements of the sequence will be expanded, and the results will be returned as a list.

The optional target and source keyword arguments must be set to lists of target and source nodes, respectively, if you want the $TARGET, $TARGETS, $SOURCE and $SOURCES to be available for expansion. This is usually necessary if you are calling env.subst from within a Python function used as an SCons action.

Returned string values or sequence elements are converted to their string representation by default. The optional conv argument may specify a conversion function that will be used in place of the default. For example, if you want Python objects (including SCons Nodes) to be returned as Python objects, you can use a Python lambda expression to pass in an unnamed function that simply returns its unconverted argument.

Example:

print(env.subst("The C compiler is: $CC"))

def compile(target, source, env):
    sourceDir = env.subst(
        "${SOURCE.srcdir}",
        target=target,
        source=source
    )

source_nodes = env.subst('$EXPAND_TO_NODELIST', conv=lambda x: x)

Tag(node, tags)

Annotates file or directory Nodes with information about how the Package Builder should package those files or directories. All Node-level tags are optional.

Examples:

# makes sure the built library will be installed with 644 file access mode
Tag(Library('lib.c'), UNIX_ATTR="0o644")

# marks file2.txt to be a documentation file
Tag('file2.txt', DOC)

Tool(name, [toolpath, key=value, ...]), env.Tool(name, [toolpath, key=value, ...])

Locates the tool specification module name and returns a callable tool object for that tool. When the environment method (env.Tool) form is used, the tool object is automatically called before the method returns to update env, and name is appended to the $TOOLS construction variable in that environment. When the global function Tool form is used, the tool object is constructed but not called, as it lacks the context of an environment to update, and the returned object needs to be used to arrange for the call.

The tool module is searched for in the tool search paths (see the Tools section in the manual page for details) and in any paths specified by the optional toolpath parameter, which must be a list of strings. If toolpath is omitted, the toolpath supplied when the environment was created, if any, is used.

Any remaining keyword arguments are saved in the tool object, and will be passed to the tool module's generate function when the tool object is actually called. The generate function can update the construction environment with construction variables and arrange any other initialization needed to use the mechanisms that tool describes, and can use these extra arguments to help guide its actions.

Changed in version 4.2: env.Tool now returns the tool object, previously it did not return (i.e. returned None).

Examples:

env.Tool('gcc')
env.Tool('opengl', toolpath=['build/tools'])

The returned tool object can be passed to an Environment or Clone call as part of the tools keyword argument, in which case the tool is applied to the environment being constructed, or it can be called directly, in which case a construction environment to update must be passed as the argument. Either approach will also update the $TOOLS construction variable.

Examples:

env = Environment(tools=[Tool('msvc')])

env = Environment()
msvctool = Tool('msvc')
msvctool(env)  # adds 'msvc' to the TOOLS variable
gltool = Tool('opengl', toolpath = ['tools'])
gltool(env)  # adds 'opengl' to the TOOLS variable

ValidateOptions([throw_exception=False])

Check that all the options specified on the command line are either SCons built-in options or defined via calls to AddOption. SCons will eventually fail on unknown options anyway, but calling this function allows the build to "fail fast" before executing expensive logic later in the build.

This function should only be called after the last AddOption call in your SConscript logic. Be aware that some tools call AddOption, if you are getting error messages for arguments that they add, you will need to ensure that those tools are loaded before calling ValidateOptions.

If there are any unknown command line options, ValidateOptions prints an error message and exits with an error exit status. If the optional throw_exception argument is True (default is False), a SConsBadOptionError is raised, giving an opportunity for the SConscript logic to catch that exception and handle invalid options appropriately. Note that this exception name needs to be imported (see the example below).

A common build problem is typos (or thinkos) - a user enters an option that is just a little off the expected value, or perhaps a different word with a similar meaning. It may be useful to abort the build before going too far down the wrong path. For example:

$ scons --compilers=mingw  # the correct flag is --compiler

Here SCons could go off and run a bunch of configure steps with the default value of --compiler, since the incorrect command line did not actually supply a value to it, costing developer time to track down why the configure logic made the "wrong" choices. This example shows catching this:

from SCons.Script.SConsOptions import SConsBadOptionError

AddOption(
    '--compiler',
    dest='compiler',
    action='store',
    default='gcc',
    type='string',
)

# ... other SConscript logic ...

try:
    ValidateOptions(throw_exception=True)
except SConsBadOptionError as e:
    print(f"ValidateOptions detects a fail: ", e.opt_str)
    Exit(3)

New in version 4.5.0

Value(value, [built_value], [name]), env.Value(value, [built_value], [name])

Returns a Node object representing the specified Python value. Value Nodes can be used as dependencies of targets. If the string representation of the Value Node changes between SCons runs, it is considered out-of-date and any targets depending on it will be rebuilt. Since Value Nodes have no filesystem representation, timestamps are not used; the timestamp deciders perform the same content-based up to date check.

The optional built_value argument can be specified when the Value Node is created to indicate the Node should already be considered "built."

The optional name parameter can be provided as an alternative name for the resulting Value node; this is advised if the value parameter cannot be converted to a string.

Value Nodes have a write method that can be used to "build" a Value Node by setting a new value. The corresponding read method returns the built value of the Node.

Changed in version 4.0: the name parameter was added.

Examples:

env = Environment()

def create(target, source, env):
    """Action function to create a file from a Value.

    Writes 'prefix=$SOURCE' into the file name given as $TARGET.
    """
    with open(str(target[0]), 'wb') as f:
        f.write(b'prefix=' + source[0].get_contents() + b'\n')

# Fetch the prefix= argument, if any, from the command line.
# Use /usr/local as the default.
prefix = ARGUMENTS.get('prefix', '/usr/local')

# Attach builder named Config to the construction environment
# using the 'create' action function above.
env['BUILDERS']['Config'] = Builder(action=create)
env.Config(target='package-config', source=Value(prefix))

def build_value(target, source, env):
    """Action function to "build" a Value.

    Writes contents of $SOURCE into $TARGET, thus updating if it existed.
    """
    target[0].write(source[0].get_contents())

output = env.Value('before')
input = env.Value('after')

# Attach a builder named UpdateValue to the construction environment
# using the 'build_value' action function above.
env['BUILDERS']['UpdateValue'] = Builder(action=build_value)
env.UpdateValue(target=Value(output), source=Value(input))

VariantDir(variant_dir, src_dir, [duplicate]), env.VariantDir(variant_dir, src_dir, [duplicate])

Sets up a mapping to define a variant build directory in variant_dir. src_dir must not be underneath variant_dir. A VariantDir mapping is global, even if called using the env.VariantDir form. VariantDir can be called multiple times with the same src_dir to set up multiple variant builds with different options.

Note if variant_dir is not under the project top directory, target selection rules will not pick targets in the variant directory unless they are explicitly specified.

When files in variant_dir are referenced, SCons backfills as needed with files from src_dir to create a complete build directory. By default, SCons physically duplicates the source files, SConscript files, and directory structure as needed into the variant directory. Thus, a build performed in the variant directory is guaranteed to be identical to a build performed in the source directory even if intermediate source files are generated during the build, or if preprocessors or other scanners search for included files using paths relative to the source file, or if individual compilers or other invoked tools are hard-coded to put derived files in the same directory as source files. Only the files SCons calculates are needed for the build are duplicated into variant_dir. If possible on the platform, the duplication is performed by linking rather than copying. This behavior is affected by the --duplicate command-line option.

Duplicating the source files may be disabled by setting the duplicate argument to False. This will cause SCons to invoke Builders using the path names of source files in src_dir and the path names of derived files within variant_dir. This is more efficient than duplicating, and is safe for most builds; revert to duplicate=True if it causes problems.

VariantDir works most naturally when used with a subsidiary SConscript file. The subsidiary SConscript file must be called as if it were in variant_dir, regardless of the value of duplicate. When calling an SConscript file, you can use the exports keyword argument to pass parameters (individually or as an appropriately set up environment) so the SConscript can pick up the right settings for that variant build. The SConscript must Import these to use them. Example:

env1 = Environment(...settings for variant1...)
env2 = Environment(...settings for variant2...)

# run src/SConscript in two variant directories
VariantDir('build/variant1', 'src')
SConscript('build/variant1/SConscript', exports={"env": env1})
VariantDir('build/variant2', 'src')
SConscript('build/variant2/SConscript', exports={"env": env2})

See also the SConscript function for another way to specify a variant directory in conjunction with calling a subsidiary SConscript file.

More examples:

# use names in the build directory, not the source directory
VariantDir('build', 'src', duplicate=0)
Program('build/prog', 'build/source.c')

# this builds both the source and docs in a separate subtree
VariantDir('build', '.', duplicate=0)
SConscript(dirs=['build/src','build/doc'])

# same as previous example, but only uses SConscript
SConscript(dirs='src', variant_dir='build/src', duplicate=0)
SConscript(dirs='doc', variant_dir='build/doc', duplicate=0)

WhereIs(program, [path, pathext, reject]), env.WhereIs(program, [path, pathext, reject])

Searches for the specified executable program, returning the full path to the program or None.

When called as a construction environment method, searches the paths in the path keyword argument, or if None (the default) the paths listed in the construction environment (env['ENV']['PATH']). The external environment's path list (os.environ['PATH']) is used as a fallback if the key env['ENV']['PATH'] does not exist.

On Windows systems, searches for executable programs with any of the file extensions listed in the pathext keyword argument, or if None (the default) the pathname extensions listed in the construction environment (env['ENV']['PATHEXT']). The external environment's pathname extensions list (os.environ['PATHEXT']) is used as a fallback if the key env['ENV']['PATHEXT'] does not exist.

When called as a global function, uses the external environment's path os.environ['PATH'] and path extensions os.environ['PATHEXT'], respectively, if path and pathext are None.

Will not select any path name or names in the optional reject list.

In addition to the global functions and methods, scons supports a number of variables that can be used for run-time queries in SConscript files to affect how you want the build to be performed.

ARGLIST

A list of the variable=value build variable arguments specified on the command line. Each element in the list is a tuple consisting of the variable and its value. The separate variable and value elements of the tuple can be accessed by subscripting for elements [0] and [1] of the tuple, or, more readably, by using tuple unpacking. Examples:

print("first variable, value =", ARGLIST[0][0], ARGLIST[0][1])
print("second variable, value =", ARGLIST[1][0], ARGLIST[1][1])
var, value = ARGLIST[2]
print("third variable, value =", var, value)
for var, value in ARGLIST:
    # process variable and value

The values obtained from ARGLIST (or from ARGUMENTS) are always strings since they originate from outside the SCons process. As "untrusted data", they should be validated before usage, and may need conversion to an appropriate type.

ARGUMENTS

A dictionary of all the variable=value build variable arguments specified on the command line. The dictionary is in command-line order, so if a given variable has more than one value assigned to it on the command line, the last (right-most) value is the one saved in the ARGUMENTS dictionary.

Example:

if ARGUMENTS.get("debug", ""):
    env = Environment(CCFLAGS="-g")
else:
    env = Environment()

See also ARGLIST.

BUILD_TARGETS

A list of the targets which scons has been asked to build. The contents will be either those targets listed on the command line, or, if none, those targets set via calls to the Default function. It does not contain any dependent targets that scons selects for building as a result of making the sure the specified targets are up to date, if those targets did not appear on the command line. The list is empty if neither command line targets nor Default calls are present.

The elements of this list may be strings or nodes, so you should run the list through the Python str function to make sure any Node path names are converted to strings.

Because this list may be taken from the list of targets specified using the Default function, the contents of the list may change on each successive call to Default. See DEFAULT_TARGETS for additional information.

Example:

if 'foo' in BUILD_TARGETS:
    print("Don't forget to test the `foo' program!")
if 'special/program' in BUILD_TARGETS:
    SConscript('special')

COMMAND_LINE_TARGETS

A list of the targets explicitly specified on the command line. If there are command line targets, this list has the same contents as BUILD_TARGETS. If there are no targets specified on the command line, this list is empty. The elements of this list are strings. This can be used, for example, to take specific actions only when a certain target(s) are explicitly requested for building.

Example:

if 'foo' in COMMAND_LINE_TARGETS:
    print("Don't forget to test the `foo' program!")
if 'special/program' in COMMAND_LINE_TARGETS:
    SConscript('special')

DEFAULT_TARGETS

A list of the target nodes that have been specified using the Default function. If there are no command line targets, this list will have the same contents as BUILD_TARGETS. Since the elements of the list are nodes, you need to call the Python str function on them to get the path name for each Node.

Example:

print(str(DEFAULT_TARGETS[0]))
if 'foo' in [str(t) for t in DEFAULT_TARGETS]:
    print("Don't forget to test the `foo' program!")

The contents of the DEFAULT_TARGETS list changes on each successive call to the Default function:

print([str(t) for t in DEFAULT_TARGETS])   # originally []
Default('foo')
print([str(t) for t in DEFAULT_TARGETS])   # now a node ['foo']
Default('bar')
print([str(t) for t in DEFAULT_TARGETS])   # now a node ['foo', 'bar']
Default(None)
print([str(t) for t in DEFAULT_TARGETS])   # back to []

Consequently, be sure to use DEFAULT_TARGETS only after you've made all of your Default() calls, or else simply be careful of the order of these statements in your SConscript files so that you don't look for a specific default target before it's actually been added to the list.

These variables may be accessed from custom Python modules that you import into an SConscript file by adding the following to the Python module:

from SCons.Script import *

Construction Variables are key-value pairs used to store information in a construction environment that is needed needed for builds using that environment. Construction variable naming must follow the same rules as Python identifier naming: the initial character must be an underscore or letter, followed by any number of underscores, letters, or digits. The convention is to use uppercase for all letters for easier visual identification.

Construction variables are used to hold many different types of information. For example, the $CPPDEFINES variable is how to tell a C/C++ compiler about preprocessor macros you need for your build. The tool discovery that SCons performs will cause the $CXX variable to hold the name of the C++ compiler, if one was detected on the system, but you can give it a different value to force a compiler command of a different name to be used. Some variables contain lists of filename suffixes that are recognized by a particular compiler chain. $BUILDERS contains a mapping of configured Builder names (e.g. Textfile) to the actual Builder instance to call when that Builder is used. Construction variables may include references to other construction variables: the same tool which set up the C/C++ compiler will also set up an "action string", describing how to invoke that compiler, in $CXXCOM, which contains other construction variables using $VARIABLE syntax. These references will be expanded and replaced on use (see Variable Substitution).

Construction variables are referenced as if they were keys and values in a Python dictionary:

env["CC"] = "cc"
flags = env.get("CPPDEFINES", [])

Construction variables can also be retrieved and set by using the Dictionary method of the construction environment to create an actual dictionary:

cvars = env.Dictionary()
cvars["CC"] = "cc"

in the previous example, since cvars is an external copy, the value of $CC in the construction environment itself is not changed by the assignment.

Construction variables can set by passing them as keyword arguments when creating a new construction environment:

env = Environment(CC="cc")

or when copying a construction environment using the Clone method:

env2 = env.Clone(CC="cl.exe")

Construction variables can also be supplied as keyword arguments to a builder, in which case those settings affect only the work done by that builder call, and not the construction environment as a whole. This concept is called an override:

env.Program('hello', 'hello.c', LIBS=['gl', 'glut'])

Many useful construction variables are automatically defined by SCons, tuned to the specific platform in use, and you can modify these or define any additional construction variables for use in your own Builders, Scanners and other tools. Take care not to overwrite ones which SCons is using. The following is a list of predefined construction variables. Pay attention to whether the values are ones you may be expected to set vs. ones that are set to expected values by internal tools and other initializations and probably should not be modified.

Note the actual list available at execution time will never include all of these, as the ones detected as not being applicable (wrong platform, necessary external command or files not installed, etc.) will not be set up. Correct build setups should be resilient to the possible absence of certain construction variables before using them, for example by using a Python dictionary get method to retrieve the value and taking alternative action if the return indicates the variable is unset. The env.Dump method can be called to examine the construction variables set in a particular environment.

__LDMODULEVERSIONFLAGS

This construction variable automatically introduces $_LDMODULEVERSIONFLAGS if $LDMODULEVERSION is set. Otherwise, it evaluates to an empty string.

__SHLIBVERSIONFLAGS

This construction variable automatically introduces $_SHLIBVERSIONFLAGS if $SHLIBVERSION is set. Otherwise, it evaluates to an empty string.

APPLELINK_COMPATIBILITY_VERSION

On Mac OS X this is used to set the linker flag: -compatibility_version

The value is specified as X[.Y[.Z]] where X is between 1 and 65535, Y can be omitted or between 1 and 255, Z can be omitted or between 1 and 255. This value will be derived from $SHLIBVERSION if not specified. The lowest digit will be dropped and replaced by a 0.

If the $APPLELINK_NO_COMPATIBILITY_VERSION is set then no -compatibility_version will be output.

See MacOS's ld manpage for more details

_APPLELINK_COMPATIBILITY_VERSION

A macro (by default a generator function) used to create the linker flags to specify apple's linker's -compatibility_version flag. The default generator uses $APPLELINK_COMPATIBILITY_VERSION and $APPLELINK_NO_COMPATIBILITY_VERSION and $SHLIBVERSION to determine the correct flag.

APPLELINK_CURRENT_VERSION

On Mac OS X this is used to set the linker flag: -current_version

The value is specified as X[.Y[.Z]] where X is between 1 and 65535, Y can be omitted or between 1 and 255, Z can be omitted or between 1 and 255. This value will be set to $SHLIBVERSION if not specified.

If the $APPLELINK_NO_CURRENT_VERSION is set then no -current_version will be output.

See MacOS's ld manpage for more details

_APPLELINK_CURRENT_VERSION

A macro (by default a generator function) used to create the linker flags to specify apple's linker's -current_version flag. The default generator uses $APPLELINK_CURRENT_VERSION and $APPLELINK_NO_CURRENT_VERSION and $SHLIBVERSION to determine the correct flag.

APPLELINK_NO_COMPATIBILITY_VERSION

Set this to any True (1|True|non-empty string) value to disable adding -compatibility_version flag when generating versioned shared libraries.

This overrides $APPLELINK_COMPATIBILITY_VERSION.

APPLELINK_NO_CURRENT_VERSION

Set this to any True (1|True|non-empty string) value to disable adding -current_version flag when generating versioned shared libraries.

This overrides $APPLELINK_CURRENT_VERSION.

AR

The static library archiver.

ARCHITECTURE

Specifies the system architecture for which the package is being built. The default is the system architecture of the machine on which SCons is running. This is used to fill in the Architecture: field in an Ipkg control file, and the BuildArch: field in the RPM .spec file, as well as forming part of the name of a generated RPM package file.

See the Package builder.

ARCOM

The command line used to generate a static library from object files.

ARCOMSTR

The string displayed when a static library is generated from object files. If this is not set, then $ARCOM (the command line) is displayed.

env = Environment(ARCOMSTR = "Archiving $TARGET")

ARFLAGS

General options passed to the static library archiver.

AS

The assembler.

ASCOM

The command line used to generate an object file from an assembly-language source file.

ASCOMSTR

The string displayed when an object file is generated from an assembly-language source file. If this is not set, then $ASCOM (the command line) is displayed.

env = Environment(ASCOMSTR = "Assembling $TARGET")

ASFLAGS

General options passed to the assembler.

ASPPCOM

The command line used to assemble an assembly-language source file into an object file after first running the file through the C preprocessor. Any options specified in the $ASFLAGS and $CPPFLAGS construction variables are included on this command line.

ASPPCOMSTR

The string displayed when an object file is generated from an assembly-language source file after first running the file through the C preprocessor. If this is not set, then $ASPPCOM (the command line) is displayed.

env = Environment(ASPPCOMSTR = "Assembling $TARGET")

ASPPFLAGS

General options when an assembling an assembly-language source file into an object file after first running the file through the C preprocessor. The default is to use the value of $ASFLAGS.

BIBTEX

The bibliography generator for the TeX formatter and typesetter and the LaTeX structured formatter and typesetter.

BIBTEXCOM

The command line used to call the bibliography generator for the TeX formatter and typesetter and the LaTeX structured formatter and typesetter.

BIBTEXCOMSTR

The string displayed when generating a bibliography for TeX or LaTeX. If this is not set, then $BIBTEXCOM (the command line) is displayed.

env = Environment(BIBTEXCOMSTR = "Generating bibliography $TARGET")

BIBTEXFLAGS

General options passed to the bibliography generator for the TeX formatter and typesetter and the LaTeX structured formatter and typesetter.

BUILDERS

A dictionary mapping the names of the builders available through the construction environment to underlying Builder objects. Custom builders need to be added to this to make them available.

A platform-dependent default list of builders such as Program, Library etc. is used to populate this construction variable when the construction environment is initialized via the presence/absence of the tools those builders depend on. $BUILDERS can be examined to learn which builders will actually be available at run-time.

Note that if you initialize this construction variable through assignment when the construction environment is created, that value for $BUILDERS will override any defaults:

bld = Builder(action='foobuild < $SOURCE > $TARGET')
env = Environment(BUILDERS={'NewBuilder': bld})

To instead use a new Builder object in addition to the default Builders, add your new Builder object like this:

env = Environment()
env.Append(BUILDERS={'NewBuilder': bld})

or this:

env = Environment()
env['BUILDERS']['NewBuilder'] = bld

CACHEDIR_CLASS

The class type that SCons should use when instantiating a new CacheDir in this construction environment. Must be a subclass of the SCons.CacheDir.CacheDir class.

CC

The C compiler.

CCCOM

The command line used to compile a C source file to a (static) object file. Any options specified in the $CFLAGS, $CCFLAGS and $CPPFLAGS construction variables are included on this command line. See also $SHCCCOM for compiling to shared objects.

CCCOMSTR

If set, the string displayed when a C source file is compiled to a (static) object file. If not set, then $CCCOM (the command line) is displayed. See also $SHCCCOMSTR for compiling to shared objects.

env = Environment(CCCOMSTR = "Compiling static object $TARGET")

CCDEPFLAGS

Options to pass to C or C++ compiler to generate list of dependency files.

This is set only by compilers which support this functionality. (gcc, clang, and msvc currently)

CCFLAGS

General options that are passed to the C and C++ compilers. See also $SHCCFLAGS for compiling to shared objects.

CCPCHFLAGS

Options added to the compiler command line to support building with precompiled headers. The default value expands expands to the appropriate Microsoft Visual C++ command-line options when the $PCH construction variable is set.

CCPDBFLAGS

Options added to the compiler command line to support storing debugging information in a Microsoft Visual C++ PDB file. The default value expands expands to appropriate Microsoft Visual C++ command-line options when the $PDB construction variable is set.

The Microsoft Visual C++ compiler option that SCons uses by default to generate PDB information is /Z7. This works correctly with parallel (-j) builds because it embeds the debug information in the intermediate object files, as opposed to sharing a single PDB file between multiple object files. This is also the only way to get debug information embedded into a static library. Using the /Zi instead may yield improved link-time performance, although parallel builds will no longer work.

You can generate PDB files with the /Zi switch by overriding the default $CCPDBFLAGS variable as follows:

env['CCPDBFLAGS'] = ['${(PDB and "/Zi /Fd%s" % File(PDB)) or ""}']

An alternative would be to use the /Zi to put the debugging information in a separate .pdb file for each object file by overriding the $CCPDBFLAGS variable as follows:

env['CCPDBFLAGS'] = '/Zi /Fd${TARGET}.pdb'

CCVERSION

The version number of the C compiler. This may or may not be set, depending on the specific C compiler being used.

CFILESUFFIX

The suffix for C source files. This is used by the internal CFile builder when generating C files from Lex (.l) or YACC (.y) input files. The default suffix, of course, is .c (lower case). On case-insensitive systems (like Windows), SCons also treats .C (upper case) files as C files.

CFLAGS

General options that are passed to the C compiler (C only; not C++). See also $SHCFLAGS for compiling to shared objects.

CHANGE_SPECFILE

A hook for modifying the file that controls the packaging build (the .spec for RPM, the control for Ipkg, the .wxs for MSI). If set, the function will be called after the SCons template for the file has been written.

See the Package builder.

CHANGED_SOURCES

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

CHANGED_TARGETS

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

CHANGELOG

The name of a file containing the change log text to be included in the package. This is included as the %changelog section of the RPM .spec file.

See the Package builder.

COMPILATIONDB_COMSTR

The string displayed when the CompilationDatabase builder's action is run.

COMPILATIONDB_PATH_FILTER

A string which instructs CompilationDatabase to only include entries where the output member matches the pattern in the filter string using fnmatch, which uses glob style wildcards.

The default value is an empty string '', which disables filtering.

COMPILATIONDB_USE_ABSPATH

A boolean flag to instruct CompilationDatabase whether to write the file and output members in the compilation database using absolute or relative paths.

The default value is False (use relative paths)

_concat

A function used to produce variables like $_CPPINCFLAGS. It takes four mandatory arguments, and up to 4 additional optional arguments: 1) a prefix to concatenate onto each element, 2) a list of elements, 3) a suffix to concatenate onto each element, 4) an environment for variable interpolation, 5) an optional function that will be called to transform the list before concatenation, 6) an optionally specified target (Can use TARGET), 7) an optionally specified source (Can use SOURCE), 8) optional affect_signature flag which will wrap non-empty returned value with $( and $) to indicate the contents should not affect the signature of the generated command line.

        env['_CPPINCFLAGS'] = '${_concat(INCPREFIX, CPPPATH, INCSUFFIX, __env__, RDirs, TARGET, SOURCE, affect_signature=False)}'

CONFIGUREDIR

The name of the directory in which Configure context test files are written. The default is .sconf_temp in the top-level directory containing the SConstruct file.

If variant directories are in use, and the configure check results should not be shared between variants, you can set $CONFIGUREDIR and $CONFIGURELOG so they are unique per variant directory.

CONFIGURELOG

The name of the Configure context log file. The default is config.log in the top-level directory containing the SConstruct file.

If variant directories are in use, and the configure check results should not be shared between variants, you can set $CONFIGUREDIR and $CONFIGURELOG so they are unique per variant directory.

_CPPDEFFLAGS

An automatically-generated construction variable containing the C preprocessor command-line options to define values. The value of $_CPPDEFFLAGS is created by respectively prepending and appending $CPPDEFPREFIX and $CPPDEFSUFFIX to each definition in $CPPDEFINES.

CPPDEFINES

A platform independent specification of C preprocessor macro definitions. The definitions are added to command lines through the automatically-generated $_CPPDEFFLAGS construction variable, which is constructed according to the contents of $CPPDEFINES:

• If $CPPDEFINES is a string, the values of the $CPPDEFPREFIX and $CPPDEFSUFFIX construction variables are respectively prepended and appended to each definition in $CPPDEFINES, split on whitespace.

  # Adds -Dxyz to POSIX compiler command lines,
  # and /Dxyz to Microsoft Visual C++ command lines.
  env = Environment(CPPDEFINES='xyz')

• If $CPPDEFINES is a list, the values of the $CPPDEFPREFIX and $CPPDEFSUFFIX construction variables are respectively prepended and appended to each element in the list. If any element is a tuple (or list) then the first item of the tuple is the macro name and the second is the macro definition. If the definition is not omitted or None, the name and definition are combined into a single name=definition item before the prepending/appending.

  # Adds -DB=2 -DA to POSIX compiler command lines,
  # and /DB=2 /DA to Microsoft Visual C++ command lines.
  env = Environment(CPPDEFINES=[('B', 2), 'A'])

• If $CPPDEFINES is a dictionary, the values of the $CPPDEFPREFIX and $CPPDEFSUFFIX construction variables are respectively prepended and appended to each key from the dictionary. If the value for a key is not None, then the key (macro name) and the value (macros definition) are combined into a single name=definition item before the prepending/appending.

  # Adds -DA -DB=2 to POSIX compiler command lines,
  # or /DA /DB=2 to Microsoft Visual C++ command lines.
  env = Environment(CPPDEFINES={'B':2, 'A':None})

Depending on how contents are added to $CPPDEFINES, it may be transformed into a compound type, for example a list containing strings, tuples and/or dictionaries. SCons can correctly expand such a compound type.

Note that SCons may call the compiler via a shell. If a macro definition contains characters such as spaces that have meaning to the shell, or is intended to be a string value, you may need to use the shell's quoting syntax to avoid interpretation by the shell before the preprocessor sees it. Function-like macros are not supported via this mechanism (and some compilers do not even implement that functionality via the command lines). When quoting, note that one set of quote characters are used to define a Python string, then quotes embedded inside that would be consumed by the shell unless escaped. These examples may help illustrate:

env = Environment(CPPDEFINES=['USE_ALT_HEADER=\\"foo_alt.h\\"'])
env = Environment(CPPDEFINES=[('USE_ALT_HEADER', '\\"foo_alt.h\\"')])

:Changed in version 4.5: SCons no longer sorts $CPPDEFINES values entered in dictionary form. Python now preserves dictionary keys in the order they are entered, so it is no longer necessary to sort them to ensure a stable command line.

CPPDEFPREFIX

The prefix used to specify preprocessor macro definitions on the C compiler command line. This will be prepended to each definition in the $CPPDEFINES construction variable when the $_CPPDEFFLAGS variable is automatically generated.

CPPDEFSUFFIX

The suffix used to specify preprocessor macro definitions on the C compiler command line. This will be appended to each definition in the $CPPDEFINES construction variable when the $_CPPDEFFLAGS variable is automatically generated.

CPPFLAGS

User-specified C preprocessor options. These will be included in any command that uses the C preprocessor, including not just compilation of C and C++ source files via the $CCCOM, $SHCCCOM, $CXXCOM and $SHCXXCOM command lines, but also the $FORTRANPPCOM, $SHFORTRANPPCOM, $F77PPCOM and $SHF77PPCOM command lines used to compile a Fortran source file, and the $ASPPCOM command line used to assemble an assembly language source file, after first running each file through the C preprocessor. Note that this variable does not contain -I (or similar) include search path options that scons generates automatically from $CPPPATH. See $_CPPINCFLAGS, below, for the variable that expands to those options.

_CPPINCFLAGS

An automatically-generated construction variable containing the C preprocessor command-line options for specifying directories to be searched for include files. The value of $_CPPINCFLAGS is created by respectively prepending and appending $INCPREFIX and $INCSUFFIX to each directory in $CPPPATH.

CPPPATH

The list of directories that the C preprocessor will search for include directories. The C/C++ implicit dependency scanner will search these directories for include files. In general, it's not advised to put include directory directives directly into $CCFLAGS or $CXXFLAGS as the result will be non-portable and the directories will not be searched by the dependency scanner. $CPPPATH should be a list of path strings, or a single string, not a pathname list joined by Python's os.pathsep.

Note: directory names in $CPPPATH will be looked-up relative to the directory of the SConscript file when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use the # prefix:

env = Environment(CPPPATH='#/include')

The directory lookup can also be forced using the Dir function:

include = Dir('include')
env = Environment(CPPPATH=include)

The directory list will be added to command lines through the automatically-generated $_CPPINCFLAGS construction variable, which is constructed by respectively prepending and appending the values of the $INCPREFIX and $INCSUFFIX construction variables to each directory in $CPPPATH. Any command lines you define that need the $CPPPATH directory list should include $_CPPINCFLAGS:

env = Environment(CCCOM="my_compiler $_CPPINCFLAGS -c -o $TARGET $SOURCE")

CPPSUFFIXES

The list of suffixes of files that will be scanned for C preprocessor implicit dependencies (#include lines). The default list is:

[".c", ".C", ".cxx", ".cpp", ".c++", ".cc",
 ".h", ".H", ".hxx", ".hpp", ".hh",
 ".F", ".fpp", ".FPP",
 ".m", ".mm",
 ".S", ".spp", ".SPP"]

CXX

The C++ compiler. See also $SHCXX for compiling to shared objects.

CXXCOM

The command line used to compile a C++ source file to an object file. Any options specified in the $CXXFLAGS and $CPPFLAGS construction variables are included on this command line. See also $SHCXXCOM for compiling to shared objects.

CXXCOMSTR

If set, the string displayed when a C++ source file is compiled to a (static) object file. If not set, then $CXXCOM (the command line) is displayed. See also $SHCXXCOMSTR for compiling to shared objects.

env = Environment(CXXCOMSTR = "Compiling static object $TARGET")

CXXFILESUFFIX

The suffix for C++ source files. This is used by the internal CXXFile builder when generating C++ files from Lex (.ll) or YACC (.yy) input files. The default suffix is .cc. SCons also treats files with the suffixes .cpp, .cxx, .c++, and .C++ as C++ files, and files with .mm suffixes as Objective-C++ files. On case-sensitive systems (Linux, UNIX, and other POSIX-alikes), SCons also treats .C (upper case) files as C++ files.

CXXFLAGS

General options that are passed to the C++ compiler. By default, this includes the value of $CCFLAGS, so that setting $CCFLAGS affects both C and C++ compilation. If you want to add C++-specific flags, you must set or override the value of $CXXFLAGS. See also $SHCXXFLAGS for compiling to shared objects.

CXXVERSION

The version number of the C++ compiler. This may or may not be set, depending on the specific C++ compiler being used.

DC

The D compiler to use. See also $SHDC for compiling to shared objects.

DCOM

The command line used to compile a D file to an object file. Any options specified in the $DFLAGS construction variable is included on this command line. See also $SHDCOM for compiling to shared objects.

DCOMSTR

If set, the string displayed when a D source file is compiled to a (static) object file. If not set, then $DCOM (the command line) is displayed. See also $SHDCOMSTR for compiling to shared objects.

DDEBUG

List of debug tags to enable when compiling.

DDEBUGPREFIX

DDEBUGPREFIX.

DDEBUGSUFFIX

DDEBUGSUFFIX.

DESCRIPTION

A long description of the project being packaged. This is included in the relevant section of the file that controls the packaging build.

See the Package builder.

DESCRIPTION_lang

A language-specific long description for the specified lang. This is used to populate a %description -l section of an RPM .spec file.

See the Package builder.

DFILESUFFIX

DFILESUFFIX.

DFLAGPREFIX

DFLAGPREFIX.

DFLAGS

General options that are passed to the D compiler.

DFLAGSUFFIX

DFLAGSUFFIX.

DI_FILE_DIR

Path where .di files will be generated

DI_FILE_DIR_PREFIX

Prefix to send the di path argument to compiler

DI_FILE_DIR_SUFFFIX

Suffix to send the di path argument to compiler

DI_FILE_SUFFIX

Suffix of d include files default is .di

DINCPREFIX

DINCPREFIX.

DINCSUFFIX

DLIBFLAGSUFFIX.

Dir

A function that converts a string into a Dir instance relative to the target being built.

Dirs

A function that converts a list of strings into a list of Dir instances relative to the target being built.

DLIB

Name of the lib tool to use for D codes.

DLIBCOM

The command line to use when creating libraries.

DLIBDIRPREFIX

DLIBLINKPREFIX.

DLIBDIRSUFFIX

DLIBLINKSUFFIX.

DLIBFLAGPREFIX

DLIBFLAGPREFIX.

DLIBFLAGSUFFIX

DLIBFLAGSUFFIX.

DLIBLINKPREFIX

DLIBLINKPREFIX.

DLIBLINKSUFFIX

DLIBLINKSUFFIX.

DLINK

Name of the linker to use for linking systems including D sources. See also $SHDLINK for linking shared objects.

DLINKCOM

The command line to use when linking systems including D sources. See also $SHDLINKCOM for linking shared objects.

DLINKFLAGPREFIX

DLINKFLAGPREFIX.

DLINKFLAGS

List of linker flags. See also $SHDLINKFLAGS for linking shared objects.

DLINKFLAGSUFFIX

DLINKFLAGSUFFIX.

DOCBOOK_DEFAULT_XSL_EPUB

The default XSLT file for the DocbookEpub builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_DEFAULT_XSL_HTML

The default XSLT file for the DocbookHtml builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_DEFAULT_XSL_HTMLCHUNKED

The default XSLT file for the DocbookHtmlChunked builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_DEFAULT_XSL_HTMLHELP

The default XSLT file for the DocbookHtmlhelp builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_DEFAULT_XSL_MAN

The default XSLT file for the DocbookMan builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_DEFAULT_XSL_PDF

The default XSLT file for the DocbookPdf builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_DEFAULT_XSL_SLIDESHTML

The default XSLT file for the DocbookSlidesHtml builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_DEFAULT_XSL_SLIDESPDF

The default XSLT file for the DocbookSlidesPdf builder within the current environment, if no other XSLT gets specified via keyword.

DOCBOOK_FOP

The path to the PDF renderer fop or xep, if one of them is installed (fop gets checked first).

DOCBOOK_FOPCOM

The full command-line for the PDF renderer fop or xep.

DOCBOOK_FOPCOMSTR

The string displayed when a renderer like fop or xep is used to create PDF output from an XML file.

DOCBOOK_FOPFLAGS

Additional command-line flags for the PDF renderer fop or xep.

DOCBOOK_XMLLINT

The path to the external executable xmllint, if it's installed. Note, that this is only used as last fallback for resolving XIncludes, if no lxml Python binding can be imported in the current system.

DOCBOOK_XMLLINTCOM

The full command-line for the external executable xmllint.

DOCBOOK_XMLLINTCOMSTR

The string displayed when xmllint is used to resolve XIncludes for a given XML file.

DOCBOOK_XMLLINTFLAGS

Additional command-line flags for the external executable xmllint.

DOCBOOK_XSLTPROC

The path to the external executable xsltproc (or saxon, xalan), if one of them is installed. Note, that this is only used as last fallback for XSL transformations, if no lxml Python binding can be imported in the current system.

DOCBOOK_XSLTPROCCOM

The full command-line for the external executable xsltproc (or saxon, xalan).

DOCBOOK_XSLTPROCCOMSTR

The string displayed when xsltproc is used to transform an XML file via a given XSLT stylesheet.

DOCBOOK_XSLTPROCFLAGS

Additional command-line flags for the external executable xsltproc (or saxon, xalan).

DOCBOOK_XSLTPROCPARAMS

Additional parameters that are not intended for the XSLT processor executable, but the XSL processing itself. By default, they get appended at the end of the command line for saxon and saxon-xslt, respectively.

DPATH

List of paths to search for import modules.

DRPATHPREFIX

DRPATHPREFIX.

DRPATHSUFFIX

DRPATHSUFFIX.

DSUFFIXES

The list of suffixes of files that will be scanned for imported D package files. The default list is ['.d'].

DVERPREFIX

DVERPREFIX.

DVERSIONS

List of version tags to enable when compiling.

DVERSUFFIX

DVERSUFFIX.

DVIPDF

The TeX DVI file to PDF file converter.

DVIPDFCOM

The command line used to convert TeX DVI files into a PDF file.

DVIPDFCOMSTR

The string displayed when a TeX DVI file is converted into a PDF file. If this is not set, then $DVIPDFCOM (the command line) is displayed.

DVIPDFFLAGS

General options passed to the TeX DVI file to PDF file converter.

DVIPS

The TeX DVI file to PostScript converter.

DVIPSFLAGS

General options passed to the TeX DVI file to PostScript converter.

ENV

The execution environment - a dictionary of environment variables used when SCons invokes external commands to build targets defined in this construction environment. When $ENV is passed to a command, all list values are assumed to be path lists and are joined using the search path separator. Any other non-string values are coerced to a string.

Note that by default SCons does not propagate the environment in effect when you execute scons (the "shell environment") to the execution environment. This is so that builds will be guaranteed repeatable regardless of the environment variables set at the time scons is invoked. If you want to propagate a shell environment variable to the commands executed to build target files, you must do so explicitly. A common example is the system PATH environment variable, so that scons will find utilities the same way as the invoking shell (or other process):

import os
env = Environment(ENV={'PATH': os.environ['PATH']})

Although it is usually not recommended, you can propagate the entire shell environment in one go:

import os
env = Environment(ENV=os.environ.copy())

ESCAPE

A function that will be called to escape shell special characters in command lines. The function should take one argument: the command line string to escape; and should return the escaped command line.

F03

The Fortran 03 compiler. You should normally set the $FORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $F03 if you need to use a specific compiler or compiler version for Fortran 03 files.

F03COM

The command line used to compile a Fortran 03 source file to an object file. You only need to set $F03COM if you need to use a specific command line for Fortran 03 files. You should normally set the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.

F03COMSTR

If set, the string displayed when a Fortran 03 source file is compiled to an object file. If not set, then $F03COM or $FORTRANCOM (the command line) is displayed.

F03FILESUFFIXES

The list of file extensions for which the F03 dialect will be used. By default, this is ['.f03']

F03FLAGS

General user-specified options that are passed to the Fortran 03 compiler. Note that this variable does not contain -I (or similar) include search path options that scons generates automatically from $F03PATH. See $_F03INCFLAGS below, for the variable that expands to those options. You only need to set $F03FLAGS if you need to define specific user options for Fortran 03 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

_F03INCFLAGS

An automatically-generated construction variable containing the Fortran 03 compiler command-line options for specifying directories to be searched for include files. The value of $_F03INCFLAGS is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in $F03PATH.

F03PATH

The list of directories that the Fortran 03 compiler will search for include directories. The implicit dependency scanner will search these directories for include files. Don't explicitly put include directory arguments in $F03FLAGS because the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in $F03PATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use #: You only need to set $F03PATH if you need to define a specific include path for Fortran 03 files. You should normally set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler for all Fortran versions.

env = Environment(F03PATH='#/include')

The directory lookup can also be forced using the Dir() function:

include = Dir('include')
env = Environment(F03PATH=include)

The directory list will be added to command lines through the automatically-generated $_F03INCFLAGS construction variable, which is constructed by appending the values of the $INCPREFIX and $INCSUFFIX construction variables to the beginning and end of each directory in $F03PATH. Any command lines you define that need the F03PATH directory list should include $_F03INCFLAGS:

env = Environment(F03COM="my_compiler $_F03INCFLAGS -c -o $TARGET $SOURCE")

F03PPCOM

The command line used to compile a Fortran 03 source file to an object file after first running the file through the C preprocessor. Any options specified in the $F03FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $F03PPCOM if you need to use a specific C-preprocessor command line for Fortran 03 files. You should normally set the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

F03PPCOMSTR

If set, the string displayed when a Fortran 03 source file is compiled to an object file after first running the file through the C preprocessor. If not set, then $F03PPCOM or $FORTRANPPCOM (the command line) is displayed.

F03PPFILESUFFIXES

The list of file extensions for which the compilation + preprocessor pass for F03 dialect will be used. By default, this is empty.

F08

The Fortran 08 compiler. You should normally set the $FORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $F08 if you need to use a specific compiler or compiler version for Fortran 08 files.

F08COM

The command line used to compile a Fortran 08 source file to an object file. You only need to set $F08COM if you need to use a specific command line for Fortran 08 files. You should normally set the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.

F08COMSTR

If set, the string displayed when a Fortran 08 source file is compiled to an object file. If not set, then $F08COM or $FORTRANCOM (the command line) is displayed.

F08FILESUFFIXES

The list of file extensions for which the F08 dialect will be used. By default, this is ['.f08']

F08FLAGS

General user-specified options that are passed to the Fortran 08 compiler. Note that this variable does not contain -I (or similar) include search path options that scons generates automatically from $F08PATH. See $_F08INCFLAGS below, for the variable that expands to those options. You only need to set $F08FLAGS if you need to define specific user options for Fortran 08 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

_F08INCFLAGS

An automatically-generated construction variable containing the Fortran 08 compiler command-line options for specifying directories to be searched for include files. The value of $_F08INCFLAGS is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in $F08PATH.

F08PATH

The list of directories that the Fortran 08 compiler will search for include directories. The implicit dependency scanner will search these directories for include files. Don't explicitly put include directory arguments in $F08FLAGS because the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in $F08PATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use #: You only need to set $F08PATH if you need to define a specific include path for Fortran 08 files. You should normally set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler for all Fortran versions.

env = Environment(F08PATH='#/include')

The directory lookup can also be forced using the Dir() function:

include = Dir('include')
env = Environment(F08PATH=include)

The directory list will be added to command lines through the automatically-generated $_F08INCFLAGS construction variable, which is constructed by appending the values of the $INCPREFIX and $INCSUFFIX construction variables to the beginning and end of each directory in $F08PATH. Any command lines you define that need the F08PATH directory list should include $_F08INCFLAGS:

env = Environment(F08COM="my_compiler $_F08INCFLAGS -c -o $TARGET $SOURCE")

F08PPCOM

The command line used to compile a Fortran 08 source file to an object file after first running the file through the C preprocessor. Any options specified in the $F08FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $F08PPCOM if you need to use a specific C-preprocessor command line for Fortran 08 files. You should normally set the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

F08PPCOMSTR

If set, the string displayed when a Fortran 08 source file is compiled to an object file after first running the file through the C preprocessor. If not set, then $F08PPCOM or $FORTRANPPCOM (the command line) is displayed.

F08PPFILESUFFIXES

The list of file extensions for which the compilation + preprocessor pass for F08 dialect will be used. By default, this is empty.

F77

The Fortran 77 compiler. You should normally set the $FORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $F77 if you need to use a specific compiler or compiler version for Fortran 77 files.

F77COM

The command line used to compile a Fortran 77 source file to an object file. You only need to set $F77COM if you need to use a specific command line for Fortran 77 files. You should normally set the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.

F77COMSTR

If set, the string displayed when a Fortran 77 source file is compiled to an object file. If not set, then $F77COM or $FORTRANCOM (the command line) is displayed.

F77FILESUFFIXES

The list of file extensions for which the F77 dialect will be used. By default, this is ['.f77']

F77FLAGS

General user-specified options that are passed to the Fortran 77 compiler. Note that this variable does not contain -I (or similar) include search path options that scons generates automatically from $F77PATH. See $_F77INCFLAGS below, for the variable that expands to those options. You only need to set $F77FLAGS if you need to define specific user options for Fortran 77 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

_F77INCFLAGS

An automatically-generated construction variable containing the Fortran 77 compiler command-line options for specifying directories to be searched for include files. The value of $_F77INCFLAGS is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in $F77PATH.

F77PATH

The list of directories that the Fortran 77 compiler will search for include directories. The implicit dependency scanner will search these directories for include files. Don't explicitly put include directory arguments in $F77FLAGS because the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in $F77PATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use #: You only need to set $F77PATH if you need to define a specific include path for Fortran 77 files. You should normally set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler for all Fortran versions.

env = Environment(F77PATH='#/include')

The directory lookup can also be forced using the Dir() function:

include = Dir('include')
env = Environment(F77PATH=include)

The directory list will be added to command lines through the automatically-generated $_F77INCFLAGS construction variable, which is constructed by appending the values of the $INCPREFIX and $INCSUFFIX construction variables to the beginning and end of each directory in $F77PATH. Any command lines you define that need the F77PATH directory list should include $_F77INCFLAGS:

env = Environment(F77COM="my_compiler $_F77INCFLAGS -c -o $TARGET $SOURCE")

F77PPCOM

The command line used to compile a Fortran 77 source file to an object file after first running the file through the C preprocessor. Any options specified in the $F77FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $F77PPCOM if you need to use a specific C-preprocessor command line for Fortran 77 files. You should normally set the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

F77PPCOMSTR

If set, the string displayed when a Fortran 77 source file is compiled to an object file after first running the file through the C preprocessor. If not set, then $F77PPCOM or $FORTRANPPCOM (the command line) is displayed.

F77PPFILESUFFIXES

The list of file extensions for which the compilation + preprocessor pass for F77 dialect will be used. By default, this is empty.

F90

The Fortran 90 compiler. You should normally set the $FORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $F90 if you need to use a specific compiler or compiler version for Fortran 90 files.

F90COM

The command line used to compile a Fortran 90 source file to an object file. You only need to set $F90COM if you need to use a specific command line for Fortran 90 files. You should normally set the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.

F90COMSTR

If set, the string displayed when a Fortran 90 source file is compiled to an object file. If not set, then $F90COM or $FORTRANCOM (the command line) is displayed.

F90FILESUFFIXES

The list of file extensions for which the F90 dialect will be used. By default, this is ['.f90']

F90FLAGS

General user-specified options that are passed to the Fortran 90 compiler. Note that this variable does not contain -I (or similar) include search path options that scons generates automatically from $F90PATH. See $_F90INCFLAGS below, for the variable that expands to those options. You only need to set $F90FLAGS if you need to define specific user options for Fortran 90 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

_F90INCFLAGS

An automatically-generated construction variable containing the Fortran 90 compiler command-line options for specifying directories to be searched for include files. The value of $_F90INCFLAGS is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in $F90PATH.

F90PATH

The list of directories that the Fortran 90 compiler will search for include directories. The implicit dependency scanner will search these directories for include files. Don't explicitly put include directory arguments in $F90FLAGS because the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in $F90PATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use #: You only need to set $F90PATH if you need to define a specific include path for Fortran 90 files. You should normally set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler for all Fortran versions.

env = Environment(F90PATH='#/include')

The directory lookup can also be forced using the Dir() function:

include = Dir('include')
env = Environment(F90PATH=include)

The directory list will be added to command lines through the automatically-generated $_F90INCFLAGS construction variable, which is constructed by appending the values of the $INCPREFIX and $INCSUFFIX construction variables to the beginning and end of each directory in $F90PATH. Any command lines you define that need the F90PATH directory list should include $_F90INCFLAGS:

env = Environment(F90COM="my_compiler $_F90INCFLAGS -c -o $TARGET $SOURCE")

F90PPCOM

The command line used to compile a Fortran 90 source file to an object file after first running the file through the C preprocessor. Any options specified in the $F90FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $F90PPCOM if you need to use a specific C-preprocessor command line for Fortran 90 files. You should normally set the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

F90PPCOMSTR

If set, the string displayed when a Fortran 90 source file is compiled after first running the file through the C preprocessor. If not set, then $F90PPCOM or $FORTRANPPCOM (the command line) is displayed.

F90PPFILESUFFIXES

The list of file extensions for which the compilation + preprocessor pass for F90 dialect will be used. By default, this is empty.

F95

The Fortran 95 compiler. You should normally set the $FORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $F95 if you need to use a specific compiler or compiler version for Fortran 95 files.

F95COM

The command line used to compile a Fortran 95 source file to an object file. You only need to set $F95COM if you need to use a specific command line for Fortran 95 files. You should normally set the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.

F95COMSTR

If set, the string displayed when a Fortran 95 source file is compiled to an object file. If not set, then $F95COM or $FORTRANCOM (the command line) is displayed.

F95FILESUFFIXES

The list of file extensions for which the F95 dialect will be used. By default, this is ['.f95']

F95FLAGS

General user-specified options that are passed to the Fortran 95 compiler. Note that this variable does not contain -I (or similar) include search path options that scons generates automatically from $F95PATH. See $_F95INCFLAGS below, for the variable that expands to those options. You only need to set $F95FLAGS if you need to define specific user options for Fortran 95 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

_F95INCFLAGS

An automatically-generated construction variable containing the Fortran 95 compiler command-line options for specifying directories to be searched for include files. The value of $_F95INCFLAGS is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in $F95PATH.

F95PATH

The list of directories that the Fortran 95 compiler will search for include directories. The implicit dependency scanner will search these directories for include files. Don't explicitly put include directory arguments in $F95FLAGS because the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in $F95PATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use #: You only need to set $F95PATH if you need to define a specific include path for Fortran 95 files. You should normally set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler for all Fortran versions.

env = Environment(F95PATH='#/include')

The directory lookup can also be forced using the Dir() function:

include = Dir('include')
env = Environment(F95PATH=include)

The directory list will be added to command lines through the automatically-generated $_F95INCFLAGS construction variable, which is constructed by appending the values of the $INCPREFIX and $INCSUFFIX construction variables to the beginning and end of each directory in $F95PATH. Any command lines you define that need the F95PATH directory list should include $_F95INCFLAGS:

env = Environment(F95COM="my_compiler $_F95INCFLAGS -c -o $TARGET $SOURCE")

F95PPCOM

The command line used to compile a Fortran 95 source file to an object file after first running the file through the C preprocessor. Any options specified in the $F95FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $F95PPCOM if you need to use a specific C-preprocessor command line for Fortran 95 files. You should normally set the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

F95PPCOMSTR

If set, the string displayed when a Fortran 95 source file is compiled to an object file after first running the file through the C preprocessor. If not set, then $F95PPCOM or $FORTRANPPCOM (the command line) is displayed.

F95PPFILESUFFIXES

The list of file extensions for which the compilation + preprocessor pass for F95 dialect will be used. By default, this is empty.

File

A function that converts a string into a File instance relative to the target being built.

FILE_ENCODING

File encoding used for files written by Textfile and Substfile. Set to "utf-8" by default.

New in version 4.5.0.

FORTRAN

The default Fortran compiler for all versions of Fortran.

FORTRANCOM

The command line used to compile a Fortran source file to an object file. By default, any options specified in the $FORTRANFLAGS, $_FORTRANMODFLAG, and $_FORTRANINCFLAGS construction variables are included on this command line.

FORTRANCOMMONFLAGS

General user-specified options that are passed to the Fortran compiler. Similar to $FORTRANFLAGS, but this construction variable is applied to all dialects.

New in version 4.4.

FORTRANCOMSTR

If set, the string displayed when a Fortran source file is compiled to an object file. If not set, then $FORTRANCOM (the command line) is displayed.

FORTRANFILESUFFIXES

The list of file extensions for which the FORTRAN dialect will be used. By default, this is ['.f', '.for', '.ftn']

FORTRANFLAGS

General user-specified options for the FORTRAN dialect that are passed to the Fortran compiler. Note that this variable does not contain -I (or similar) include or module search path options that scons generates automatically from $FORTRANPATH. See $_FORTRANINCFLAGS and $_FORTRANMODFLAG for the construction variables that expand those options.

_FORTRANINCFLAGS

An automatically-generated construction variable containing the Fortran compiler command-line options for specifying directories to be searched for include files and module files. The value of $_FORTRANINCFLAGS is created by respectively prepending and appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in $FORTRANPATH.

FORTRANMODDIR

Directory location where the Fortran compiler should place any module files it generates. This variable is empty, by default. Some Fortran compilers will internally append this directory in the search path for module files, as well.

FORTRANMODDIRPREFIX

The prefix used to specify a module directory on the Fortran compiler command line. This will be prepended to the beginning of the directory in the $FORTRANMODDIR construction variables when the $_FORTRANMODFLAG variables is automatically generated.

FORTRANMODDIRSUFFIX

The suffix used to specify a module directory on the Fortran compiler command line. This will be appended to the end of the directory in the $FORTRANMODDIR construction variables when the $_FORTRANMODFLAG variables is automatically generated.

_FORTRANMODFLAG

An automatically-generated construction variable containing the Fortran compiler command-line option for specifying the directory location where the Fortran compiler should place any module files that happen to get generated during compilation. The value of $_FORTRANMODFLAG is created by respectively prepending and appending $FORTRANMODDIRPREFIX and $FORTRANMODDIRSUFFIX to the beginning and end of the directory in $FORTRANMODDIR.

FORTRANMODPREFIX

The module file prefix used by the Fortran compiler. SCons assumes that the Fortran compiler follows the quasi-standard naming convention for module files of module_name.mod. As a result, this variable is left empty, by default. For situations in which the compiler does not necessarily follow the normal convention, the user may use this variable. Its value will be appended to every module file name as scons attempts to resolve dependencies.

FORTRANMODSUFFIX

The module file suffix used by the Fortran compiler. SCons assumes that the Fortran compiler follows the quasi-standard naming convention for module files of module_name.mod. As a result, this variable is set to ".mod", by default. For situations in which the compiler does not necessarily follow the normal convention, the user may use this variable. Its value will be appended to every module file name as scons attempts to resolve dependencies.

FORTRANPATH

The list of directories that the Fortran compiler will search for include files and (for some compilers) module files. The Fortran implicit dependency scanner will search these directories for include files (but not module files since they are autogenerated and, as such, may not actually exist at the time the scan takes place). Don't explicitly put include directory arguments in FORTRANFLAGS because the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in FORTRANPATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use #:

env = Environment(FORTRANPATH='#/include')

The directory look-up can also be forced using the Dir() function:

include = Dir('include')
env = Environment(FORTRANPATH=include)

The directory list will be added to command lines through the automatically-generated $_FORTRANINCFLAGS construction variable, which is constructed by respectively prepending and appending the values of the $INCPREFIX and $INCSUFFIX construction variables to the beginning and end of each directory in $FORTRANPATH. Any command lines you define that need the FORTRANPATH directory list should include $_FORTRANINCFLAGS:

env = Environment(FORTRANCOM="my_compiler $_FORTRANINCFLAGS -c -o $TARGET $SOURCE")

FORTRANPPCOM

The command line used to compile a Fortran source file to an object file after first running the file through the C preprocessor. By default, any options specified in the $FORTRANFLAGS, $CPPFLAGS, $_CPPDEFFLAGS, $_FORTRANMODFLAG, and $_FORTRANINCFLAGS construction variables are included on this command line.

FORTRANPPCOMSTR

If set, the string displayed when a Fortran source file is compiled to an object file after first running the file through the C preprocessor. If not set, then $FORTRANPPCOM (the command line) is displayed.

FORTRANPPFILESUFFIXES

The list of file extensions for which the compilation + preprocessor pass for FORTRAN dialect will be used. By default, this is ['.fpp', '.FPP']

FORTRANSUFFIXES

The list of suffixes of files that will be scanned for Fortran implicit dependencies (INCLUDE lines and USE statements). The default list is:

[".f", ".F", ".for", ".FOR", ".ftn", ".FTN", ".fpp", ".FPP",
".f77", ".F77", ".f90", ".F90", ".f95", ".F95"]

FRAMEWORKPATH

On Mac OS X with gcc, a list containing the paths to search for frameworks. Used by the compiler to find framework-style includes like #include <Fmwk/Header.h>. Used by the linker to find user-specified frameworks when linking (see $FRAMEWORKS). For example:

env.AppendUnique(FRAMEWORKPATH='#myframeworkdir')

will add

... -Fmyframeworkdir

to the compiler and linker command lines.

_FRAMEWORKPATH

On Mac OS X with gcc, an automatically-generated construction variable containing the linker command-line options corresponding to $FRAMEWORKPATH.

FRAMEWORKPATHPREFIX

On Mac OS X with gcc, the prefix to be used for the FRAMEWORKPATH entries. (see $FRAMEWORKPATH). The default value is -F.

FRAMEWORKPREFIX

On Mac OS X with gcc, the prefix to be used for linking in frameworks (see $FRAMEWORKS). The default value is -framework.

FRAMEWORKS

On Mac OS X with gcc, a list of the framework names to be linked into a program or shared library or bundle. The default value is the empty list. For example:

env.AppendUnique(FRAMEWORKS=Split('System Cocoa SystemConfiguration'))

_FRAMEWORKS

On Mac OS X with gcc, an automatically-generated construction variable containing the linker command-line options for linking with FRAMEWORKS.

FRAMEWORKSFLAGS

On Mac OS X with gcc, general user-supplied frameworks options to be added at the end of a command line building a loadable module. (This has been largely superseded by the $FRAMEWORKPATH, $FRAMEWORKPATHPREFIX, $FRAMEWORKPREFIX and $FRAMEWORKS variables described above.)

GS

The Ghostscript program used to, for example, convert PostScript to PDF files.

GSCOM

The full Ghostscript command line used for the conversion process. Its default value is “$GS $GSFLAGS -sOutputFile=$TARGET $SOURCES”.

GSCOMSTR

The string displayed when Ghostscript is called for the conversion process. If this is not set (the default), then $GSCOM (the command line) is displayed.

GSFLAGS

General options passed to the Ghostscript program, when converting PostScript to PDF files for example. Its default value is “-dNOPAUSE -dBATCH -sDEVICE=pdfwrite”

HOST_ARCH

The name of the host hardware architecture used to create this construction environment. The platform code sets this when initializing (see $PLATFORM and the platform argument to Environment). Note the detected name of the architecture may not be identical to that returned by the Python platform.machine method.

On the win32 platform, if the Microsoft Visual C++ compiler is available, msvc tool setup is done using $HOST_ARCH and $TARGET_ARCH. Changing the values at any later time will not cause the tool to be reinitialized. Valid host arch values are x86 and arm for 32-bit hosts and amd64, arm64, and x86_64 for 64-bit hosts.

Should be considered immutable. $HOST_ARCH is not currently used by other platforms, but the option is reserved to do so in future

HOST_OS

The name of the host operating system for the platform used to create this construction environment. The platform code sets this when initializing (see $PLATFORM and the platform argument to Environment).

Should be considered immutable. $HOST_OS is not currently used by SCons, but the option is reserved to do so in future

IDLSUFFIXES

The list of suffixes of files that will be scanned for IDL implicit dependencies (#include or import lines). The default list is:

[".idl", ".IDL"]

IMPLIBNOVERSIONSYMLINKS

Used to override $SHLIBNOVERSIONSYMLINKS/$LDMODULENOVERSIONSYMLINKS when creating versioned import library for a shared library/loadable module. If not defined, then $SHLIBNOVERSIONSYMLINKS/$LDMODULENOVERSIONSYMLINKS is used to determine whether to disable symlink generation or not.

IMPLIBPREFIX

The prefix used for import library names. For example, cygwin uses import libraries (libfoo.dll.a) in pair with dynamic libraries (cygfoo.dll). The cyglink linker sets $IMPLIBPREFIX to 'lib' and $SHLIBPREFIX to 'cyg'.

IMPLIBSUFFIX

The suffix used for import library names. For example, cygwin uses import libraries (libfoo.dll.a) in pair with dynamic libraries (cygfoo.dll). The cyglink linker sets $IMPLIBSUFFIX to '.dll.a' and $SHLIBSUFFIX to '.dll'.

IMPLIBVERSION

Used to override $SHLIBVERSION/$LDMODULEVERSION when generating versioned import library for a shared library/loadable module. If undefined, the $SHLIBVERSION/$LDMODULEVERSION is used to determine the version of versioned import library.

IMPLICIT_COMMAND_DEPENDENCIES

Controls whether or not SCons will add implicit dependencies for the commands executed to build targets.

By default, SCons will add to each target an implicit dependency on the command represented by the first argument of any command line it executes (which is typically the command itself). By setting such a dependency, SCons can determine that a target should be rebuilt if the command changes, such as when a compiler is upgraded to a new version. The specific file for the dependency is found by searching the PATH variable in the ENV dictionary in the construction environment used to execute the command. The default is the same as setting the construction variable $IMPLICIT_COMMAND_DEPENDENCIES to a True-like value (“true”, “yes”, or “1” - but not a number greater than one, as that has a different meaning).

Action strings can be segmented by the use of an AND operator, &&. In a segmented string, each segment is a separate “command line”, these are run sequentially until one fails, or the entire sequence has been executed. If an action string is segmented, then the selected behavior of $IMPLICIT_COMMAND_DEPENDENCIES is applied to each segment.

If $IMPLICIT_COMMAND_DEPENDENCIES is set to a False-like value (“none”, “false”, “no”, “0”, etc.), then the implicit dependency will not be added to the targets built with that construction environment.

If $IMPLICIT_COMMAND_DEPENDENCIES is set to “2” or higher, then that number of arguments in the command line will be scanned for relative or absolute paths. If any are present, they will be added as implicit dependencies to the targets built with that construction environment. The first argument in the command line will be searched for using the PATH variable in the ENV dictionary in the construction environment used to execute the command. The other arguments will only be found if they are absolute paths or valid paths relative to the working directory.

If $IMPLICIT_COMMAND_DEPENDENCIES is set to “all”, then all arguments in the command line will be scanned for relative or absolute paths. If any are present, they will be added as implicit dependencies to the targets built with that construction environment. The first argument in the command line will be searched for using the PATH variable in the ENV dictionary in the construction environment used to execute the command. The other arguments will only be found if they are absolute paths or valid paths relative to the working directory.

env = Environment(IMPLICIT_COMMAND_DEPENDENCIES=False)

INCPREFIX

The prefix used to specify an include directory on the C compiler command line. This will be prepended to each directory in the $CPPPATH and $FORTRANPATH construction variables when the $_CPPINCFLAGS and $_FORTRANINCFLAGS variables are automatically generated.

INCSUFFIX

The suffix used to specify an include directory on the C compiler command line. This will be appended to each directory in the $CPPPATH and $FORTRANPATH construction variables when the $_CPPINCFLAGS and $_FORTRANINCFLAGS variables are automatically generated.

INSTALL

A function to be called to install a file into a destination file name. The default function copies the file into the destination (and sets the destination file's mode and permission bits to match the source file's). The function takes the following arguments:

def install(dest, source, env):

dest is the path name of the destination file. source is the path name of the source file. env is the construction environment (a dictionary of construction values) in force for this file installation.

INSTALLSTR

The string displayed when a file is installed into a destination file name. The default is:

Install file: "$SOURCE" as "$TARGET"

INTEL_C_COMPILER_VERSION

Set by the intelc Tool to the major version number of the Intel C compiler selected for use.

JAR

The Java archive tool.

JARCHDIR

The directory to which the Java archive tool should change (using the -C option).

JARCOM

The command line used to call the Java archive tool.

JARCOMSTR

The string displayed when the Java archive tool is called If this is not set, then $JARCOM (the command line) is displayed.

env = Environment(JARCOMSTR="JARchiving $SOURCES into $TARGET")

JARFLAGS

General options passed to the Java archive tool. By default, this is set to cf to create the necessary jar file.

JARSUFFIX

The suffix for Java archives: .jar by default.

JAVABOOTCLASSPATH

Specifies the location of the bootstrap class files. Can be specified as a string or Node object, or as a list of strings or Node objects.

The value will be added to the JDK command lines via the -bootclasspath option, which requires a system-specific search path separator. This will be supplied by SCons as needed when it constructs the command line if $JAVABOOTCLASSPATH is provided in list form. If $JAVABOOTCLASSPATH is a single string containing search path separator characters (: for POSIX systems or ; for Windows), it will not be modified; and so is inherently system-specific; to supply the path in a system-independent manner, give $JAVABOOTCLASSPATH as a list of paths instead.

Note
Can only be used when compiling for releases prior to JDK 9.

JAVAC

The Java compiler.

JAVACCOM

The command line used to compile a directory tree containing Java source files to corresponding Java class files. Any options specified in the $JAVACFLAGS construction variable are included on this command line.

JAVACCOMSTR

The string displayed when compiling a directory tree of Java source files to corresponding Java class files. If this is not set, then $JAVACCOM (the command line) is displayed.

env = Environment(JAVACCOMSTR="Compiling class files $TARGETS from $SOURCES")

JAVACFLAGS

General options that are passed to the Java compiler.

JAVACLASSDIR

The directory in which Java class files may be found. This is stripped from the beginning of any Java .class file names supplied to the JavaH builder.

JAVACLASSPATH

Specifies the class search path for the JDK tools. Can be specified as a string or Node object, or as a list of strings or Node objects. Class path entries may be directory names to search for class files or packages, pathnames to archives (.jar or .zip) containing classes, or paths ending in a "base name wildcard" character (*), which matches files in that directory with a .jar suffix. See the Java documentation for more details.

The value will be added to the JDK command lines via the -classpath option, which requires a system-specific search path separator. This will be supplied by SCons as needed when it constructs the command line if $JAVACLASSPATH is provided in list form. If $JAVACLASSPATH is a single string containing search path separator characters (: for POSIX systems or ; for Windows), it will be split on the separator into a list of individual paths for dependency scanning purposes. It will not be modified for JDK command-line usage, so such a string is inherently system-specific; to supply the path in a system-independent manner, give $JAVACLASSPATH as a list of paths instead.

Note

SCons always supplies a -sourcepath when invoking the Java compiler javac, regardless of the setting of $JAVASOURCEPATH, as it passes the path(s) to the source(s) supplied in the call to the Java builder via -sourcepath . From the documentation of the standard Java toolkit for javac: “If not compiling code for modules, if the --source-path or -sourcepath option is not specified, then the user class path is also searched for source files.” Since -sourcepath is always supplied, javac will not use the contents of the value of $JAVACLASSPATH when searching for sources.

JAVACLASSSUFFIX

The suffix for Java class files; .class by default.

JAVAH

The Java generator for C header and stub files.

JAVAHCOM

The command line used to generate C header and stub files from Java classes. Any options specified in the $JAVAHFLAGS construction variable are included on this command line.

JAVAHCOMSTR

The string displayed when C header and stub files are generated from Java classes. If this is not set, then $JAVAHCOM (the command line) is displayed.

env = Environment(JAVAHCOMSTR="Generating header/stub file(s) $TARGETS from $SOURCES")

JAVAHFLAGS

General options passed to the C header and stub file generator for Java classes.

JAVAINCLUDES

Include path for Java header files (such as jni.h).

JAVAPROCESSORPATH

Specifies the location of the annotation processor class files. Can be specified as a string or Node object, or as a list of strings or Node objects.

The value will be added to the JDK command lines via the -processorpath option, which requires a system-specific search path separator. This will be supplied by SCons as needed when it constructs the command line if $JAVAPROCESSORPATH is provided in list form. If $JAVAPROCESSORPATH is a single string containing search path separator characters (: for POSIX systems or ; for Windows), it will not be modified; and so is inherently system-specific; to supply the path in a system-independent manner, give $JAVAPROCESSORPATH as a list of paths instead.

New in version 4.5.0

JAVASOURCEPATH

Specifies the list of directories that will be searched for input (source) .java files. Can be specified as a string or Node object, or as a list of strings or Node objects.

The value will be added to the JDK command lines via the -sourcepath option, which requires a system-specific search path separator, This will be supplied by SCons as needed when it constructs the command line if $JAVASOURCEPATH is provided in list form. If $JAVASOURCEPATH is a single string containing search path separator characters (: for POSIX systems or ; for Windows), it will not be modified, and so is inherently system-specific; to supply the path in a system-independent manner, give $JAVASOURCEPATH as a list of paths instead.

Note that the specified directories are only added to the command line via the -sourcepath option. SCons does not currently search the $JAVASOURCEPATH directories for dependent .java files.

JAVASUFFIX

The suffix for Java files; .java by default.

JAVAVERSION

Specifies the Java version being used by the Java builder. Set this to specify the version of Java targeted by the javac compiler. This is sometimes necessary because Java 1.5 changed the file names that are created for nested anonymous inner classes, which can cause a mismatch with the files that SCons expects will be generated by the javac compiler. Setting $JAVAVERSION to a version greater than 1.4 makes SCons realize that a build with such a compiler is actually up-to-date. The default is 1.4.

While this is not primarily intended for selecting one version of the Java compiler vs. another, it does have that effect on the Windows platform. A more precise approach is to set $JAVAC (and related construction variables for related utilities) to the path to the specific Java compiler you want, if that is not the default compiler. On non-Windows platforms, the alternatives system may provide a way to adjust the default Java compiler without having to specify explicit paths.

LATEX

The LaTeX structured formatter and typesetter.

LATEXCOM

The command line used to call the LaTeX structured formatter and typesetter.

LATEXCOMSTR

The string displayed when calling the LaTeX structured formatter and typesetter. If this is not set, then $LATEXCOM (the command line) is displayed.

env = Environment(LATEXCOMSTR = "Building $TARGET from LaTeX input $SOURCES")

LATEXFLAGS

General options passed to the LaTeX structured formatter and typesetter.

LATEXRETRIES

The maximum number of times that LaTeX will be re-run if the .log generated by the $LATEXCOM command indicates that there are undefined references. The default is to try to resolve undefined references by re-running LaTeX up to three times.

LATEXSUFFIXES

The list of suffixes of files that will be scanned for LaTeX implicit dependencies (\include or \import files). The default list is:

[".tex", ".ltx", ".latex"]

LDMODULE

The linker for building loadable modules. By default, this is the same as $SHLINK.

LDMODULECOM

The command line for building loadable modules. On Mac OS X, this uses the $LDMODULE, $LDMODULEFLAGS and $FRAMEWORKSFLAGS variables. On other systems, this is the same as $SHLINK.

LDMODULECOMSTR

If set, the string displayed when building loadable modules. If not set, then $LDMODULECOM (the command line) is displayed.

LDMODULEEMITTER

Contains the emitter specification for the LoadableModule builder. The manpage section "Builder Objects" contains general information on specifying emitters.

LDMODULEFLAGS

General user options passed to the linker for building loadable modules.

LDMODULENOVERSIONSYMLINKS

Instructs the LoadableModule builder to not automatically create symlinks for versioned modules. Defaults to $SHLIBNOVERSIONSYMLINKS

LDMODULEPREFIX

The prefix used for loadable module file names. On Mac OS X, this is null; on other systems, this is the same as $SHLIBPREFIX.

_LDMODULESONAME

A macro that automatically generates loadable module's SONAME based on $TARGET, $LDMODULEVERSION and $LDMODULESUFFIX. Used by LoadableModule builder when the linker tool supports SONAME (e.g. gnulink).

LDMODULESUFFIX

The suffix used for loadable module file names. On Mac OS X, this is null; on other systems, this is the same as $SHLIBSUFFIX.

LDMODULEVERSION

When this construction variable is defined, a versioned loadable module is created by LoadableModule builder. This activates the $_LDMODULEVERSIONFLAGS and thus modifies the $LDMODULECOM as required, adds the version number to the library name, and creates the symlinks that are needed. $LDMODULEVERSION versions should exist in the same format as $SHLIBVERSION.

_LDMODULEVERSIONFLAGS

This macro automatically introduces extra flags to $LDMODULECOM when building versioned LoadableModule (that is when $LDMODULEVERSION is set). _LDMODULEVERSIONFLAGS usually adds $SHLIBVERSIONFLAGS and some extra dynamically generated options (such as -Wl,-soname=$_LDMODULESONAME). It is unused by plain (unversioned) loadable modules.

LDMODULEVERSIONFLAGS

Extra flags added to $LDMODULECOM when building versioned LoadableModule. These flags are only used when $LDMODULEVERSION is set.

LEX

The lexical analyzer generator.

LEX_HEADER_FILE

If supplied, generate a C header file with the name taken from this variable. Will be emitted as a --header-file= command-line option. Use this in preference to including --header-file= in $LEXFLAGS directly.

LEX_TABLES_FILE

If supplied, write the lex tables to a file with the name taken from this variable. Will be emitted as a --tables-file= command-line option. Use this in preference to including --tables-file= in $LEXFLAGS directly.

LEXCOM

The command line used to call the lexical analyzer generator to generate a source file.

LEXCOMSTR

The string displayed when generating a source file using the lexical analyzer generator. If this is not set, then $LEXCOM (the command line) is displayed.

env = Environment(LEXCOMSTR="Lex'ing $TARGET from $SOURCES")

LEXFLAGS

General options passed to the lexical analyzer generator. In addition to passing the value on during invocation, the lex tool also examines this construction variable for options which cause additional output files to be generated, and adds those to the target list. Recognized for this purpose are GNU flex options --header-file= and --tables-file=; the output file is named by the option argument.

Note that files specified by --header-file= and --tables-file= may not be properly handled by SCons in all situations. Consider using $LEX_HEADER_FILE and $LEX_TABLES_FILE instead.

LEXUNISTD

Used only in Windows environments to set a lex flag to prevent 'unistd.h' from being included. The default value is '--nounistd'.

_LIBDIRFLAGS

An automatically-generated construction variable containing the linker command-line options for specifying directories to be searched for library. The value of $_LIBDIRFLAGS is created by respectively prepending and appending $LIBDIRPREFIX and $LIBDIRSUFFIX to each directory in $LIBPATH.

LIBDIRPREFIX

The prefix used to specify a library directory on the linker command line. This will be prepended to each directory in the $LIBPATH construction variable when the $_LIBDIRFLAGS variable is automatically generated.

LIBDIRSUFFIX

The suffix used to specify a library directory on the linker command line. This will be appended to each directory in the $LIBPATH construction variable when the $_LIBDIRFLAGS variable is automatically generated.

LIBEMITTER

Contains the emitter specification for the StaticLibrary builder. The manpage section "Builder Objects" contains general information on specifying emitters.

_LIBFLAGS

An automatically-generated construction variable containing the linker command-line options for specifying libraries to be linked with the resulting target. The value of $_LIBFLAGS is created by respectively prepending and appending $LIBLINKPREFIX and $LIBLINKSUFFIX to each filename in $LIBS.

LIBLINKPREFIX

The prefix used to specify a library to link on the linker command line. This will be prepended to each library in the $LIBS construction variable when the $_LIBFLAGS variable is automatically generated.

LIBLINKSUFFIX

The suffix used to specify a library to link on the linker command line. This will be appended to each library in the $LIBS construction variable when the $_LIBFLAGS variable is automatically generated.

LIBLITERALPREFIX

If the linker supports command line syntax directing that the argument specifying a library should be searched for literally (without modification), $LIBLITERALPREFIX can be set to that indicator. For example, the GNU linker follows this rule: “ -l:foo searches the library path for a filename called foo, without converting it to libfoo.so or libfoo.a. ” If $LIBLITERALPREFIX is set, SCons will not transform a string-valued entry in $LIBS that starts with that string. The entry will still be surrounded with $LIBLINKPREFIX and $LIBLINKSUFFIX on the command line. This is useful, for example, in directing that a static library be used when both a static and dynamic library are available and linker policy is to prefer dynamic libraries. Compared to the example in $LIBS,

env.Append(LIBS=":libmylib.a")

will let the linker select that specific (static) library name if found in the library search path. This differs from using a File object to specify the static library, as the latter bypasses the library search path entirely.

LIBPATH

The list of directories that will be searched for libraries specified by the $LIBS construction variable. $LIBPATH should be a list of path strings, or a single string, not a pathname list joined by Python's os.pathsep.

Do not put library search directives directly into $LINKFLAGS or $SHLINKFLAGS as the result will be non-portable.

Note: directory names in $LIBPATH will be looked-up relative to the directory of the SConscript file when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use the # prefix:

env = Environment(LIBPATH='#/libs')

The directory lookup can also be forced using the Dir function:

libs = Dir('libs')
env = Environment(LIBPATH=libs)

The directory list will be added to command lines through the automatically-generated $_LIBDIRFLAGS construction variable, which is constructed by respectively prepending and appending the values of the $LIBDIRPREFIX and $LIBDIRSUFFIX construction variables to each directory in $LIBPATH. Any command lines you define that need the $LIBPATH directory list should include $_LIBDIRFLAGS:

env = Environment(LINKCOM="my_linker $_LIBDIRFLAGS $_LIBFLAGS -o $TARGET $SOURCE")

LIBPREFIX

The prefix used for (static) library file names. A default value is set for each platform (posix, win32, os2, etc.), but the value is overridden by individual tools (ar, mslib, sgiar, sunar, tlib, etc.) to reflect the names of the libraries they create.

LIBPREFIXES

A list of all legal prefixes for library file names on the current platform. When searching for library dependencies, SCons will look for files with these prefixes, the base library name, and suffixes from the $LIBSUFFIXES list.

LIBS

The list of libraries that will be added to the link line for linking with any executable program, shared library, or loadable module created by the construction environment or override.

For portability, a string-valued library name should include only the base library name, without prefixes such as lib or suffixes such as .so or .dll. SCons will attempt to strip prefixes from the $LIBPREFIXES list and suffixes from the $LIBSUFFIXES list, but depending on that behavior will make the build less portable: for example, on a POSIX system, no attempt will be made to strip a suffix like .dll. Library name strings in $LIBS should not include a path component: instead use $LIBPATH to direct the compiler to look for libraries in those paths, plus any default paths the linker searches in. If $LIBLITERALPREFIX is set to a non-empty string, then a string-valued $LIBS entry that starts with $LIBLITERALPREFIX will cause the rest of the entry to be searched for unmodified, but respecting normal library search paths (this is an exception to the guideline above about leaving off the prefix/suffix from the library name).

If a $LIBS entry is a Node object (either as returned by a previous Builder call, or as the result of an explicit call to File), the pathname from that Node will be added to $_LIBFLAGS, and thus to the link line, unmodified - without adding $LIBLINKPREFIX or $LIBLINKSUFFIX. Such entries are searched for literally (including any path component); the library search paths are not used. For example:

env.Append(LIBS=File('/tmp/mylib.so'))

For each Builder call that causes linking with libraries, SCons will add the libraries in the setting of $LIBS in effect at that moment to the dependency graph as dependencies of the target being generated.

The library list will be transformed to command-line arguments through the automatically-generated $_LIBFLAGS construction variable which is constructed by respectively prepending and appending the values of the $LIBLINKPREFIX and $LIBLINKSUFFIX construction variables to each library name.

Any command lines you define yourself that need the libraries from $LIBS should include $_LIBFLAGS (as well as $_LIBDIRFLAGS) rather than $LIBS. For example:

env = Environment(LINKCOM="my_linker $_LIBDIRFLAGS $_LIBFLAGS -o $TARGET $SOURCE")

LIBSUFFIX

The suffix used for (static) library file names. A default value is set for each platform (posix, win32, os2, etc.), but the value is overridden by individual tools (ar, mslib, sgiar, sunar, tlib, etc.) to reflect the names of the libraries they create.

LIBSUFFIXES

A list of all legal suffixes for library file names. on the current platform. When searching for library dependencies, SCons will look for files with prefixes from the $LIBPREFIXES list, the base library name, and these suffixes.

LICENSE

The abbreviated name, preferably the SPDX code, of the license under which this project is released (GPL-3.0, LGPL-2.1, BSD-2-Clause etc.). See http://www.opensource.org/licenses/alphabetical^[8] for a list of license names and SPDX codes.

See the Package builder.

LINESEPARATOR

The separator used by the Substfile and Textfile builders. This value is used between sources when constructing the target. It defaults to the current system line separator.

LINGUAS_FILE

The $LINGUAS_FILE defines file(s) containing list of additional linguas to be processed by POInit, POUpdate or MOFiles builders. It also affects Translate builder. If the variable contains a string, it defines the name of the list file. The $LINGUAS_FILE may be a list of file names as well. If $LINGUAS_FILE is set to a non-string truthy value, the list will be read from the file named LINGUAS.

LINK

The linker. See also $SHLINK for linking shared objects.

On POSIX systems (those using the link tool), you should normally not change this value as it defaults to a "smart" linker tool which selects a compiler driver matching the type of source files in use. So for example, if you set $CXX to a specific compiler name, and are compiling C++ sources, the smartlink function will automatically select the same compiler for linking.

LINKCOM

The command line used to link object files into an executable. See also $SHLINKCOM for linking shared objects.

LINKCOMSTR

If set, the string displayed when object files are linked into an executable. If not set, then $LINKCOM (the command line) is displayed. See also $SHLINKCOMSTR. for linking shared objects.

env = Environment(LINKCOMSTR = "Linking $TARGET")

LINKFLAGS

General user options passed to the linker. Note that this variable should not contain -l (or similar) options for linking with the libraries listed in $LIBS, nor -L (or similar) library search path options that scons generates automatically from $LIBPATH. See $_LIBFLAGS above, for the variable that expands to library-link options, and $_LIBDIRFLAGS above, for the variable that expands to library search path options. See also $SHLINKFLAGS. for linking shared objects.

M4

The M4 macro preprocessor.

M4COM

The command line used to pass files through the M4 macro preprocessor.

M4COMSTR

The string displayed when a file is passed through the M4 macro preprocessor. If this is not set, then $M4COM (the command line) is displayed.

M4FLAGS

General options passed to the M4 macro preprocessor.

MAKEINDEX

The makeindex generator for the TeX formatter and typesetter and the LaTeX structured formatter and typesetter.

MAKEINDEXCOM

The command line used to call the makeindex generator for the TeX formatter and typesetter and the LaTeX structured formatter and typesetter.

MAKEINDEXCOMSTR

The string displayed when calling the makeindex generator for the TeX formatter and typesetter and the LaTeX structured formatter and typesetter. If this is not set, then $MAKEINDEXCOM (the command line) is displayed.

MAKEINDEXFLAGS

General options passed to the makeindex generator for the TeX formatter and typesetter and the LaTeX structured formatter and typesetter.

MAXLINELENGTH

The maximum number of characters allowed on an external command line. On Win32 systems, link lines longer than this many characters are linked via a temporary file name.

MIDL

The Microsoft IDL compiler.

MIDLCOM

The command line used to pass files to the Microsoft IDL compiler.

MIDLCOMSTR

The string displayed when the Microsoft IDL compiler is called. If this is not set, then $MIDLCOM (the command line) is displayed.

MIDLFLAGS

General options passed to the Microsoft IDL compiler.

MOSUFFIX

Suffix used for MO files (default: '.mo'). See msgfmt tool and MOFiles builder.

MSGFMT

Absolute path to msgfmt(1) binary, found by Detect(). See msgfmt tool and MOFiles builder.

MSGFMTCOM

Complete command line to run msgfmt(1) program. See msgfmt tool and MOFiles builder.

MSGFMTCOMSTR

String to display when msgfmt(1) is invoked (default: '', which means “print $MSGFMTCOM”). See msgfmt tool and MOFiles builder.

MSGFMTFLAGS

Additional flags to msgfmt(1). See msgfmt tool and MOFiles builder.

MSGINIT

Path to msginit(1) program (found via Detect). See msginit tool and POInit builder.

MSGINITCOM

Complete command line to run msginit(1) program. See msginit tool and POInit builder.

MSGINITCOMSTR

String to display when msginit(1) is invoked. The default is an empty string, which will print the command line ($MSGINITCOM). See msginit tool and POInit builder.

MSGINITFLAGS

List of additional flags to msginit(1) (default: []). See msginit tool and POInit builder.

_MSGINITLOCALE

Internal “macro”. Computes locale (language) name based on target filename (default: '${TARGET.filebase}').

See msginit tool and POInit builder.

MSGMERGE

Absolute path to msgmerge(1) binary as found by Detect(). See msgmerge tool and POUpdate builder.

MSGMERGECOM

Complete command line to run msgmerge(1) command. See msgmerge tool and POUpdate builder.

MSGMERGECOMSTR

String to be displayed when msgmerge(1) is invoked. The default is an empty string, which will print the command line ($MSGMERGECOM). See msgmerge tool and POUpdate builder.

MSGMERGEFLAGS

Additional flags to msgmerge(1) command. See msgmerge tool and POUpdate builder.

MSSDK_DIR

The directory containing the Microsoft SDK (either Platform SDK or Windows SDK) to be used for compilation.

MSSDK_VERSION

The version string of the Microsoft SDK (either Platform SDK or Windows SDK) to be used for compilation. Supported versions include 6.1, 6.0A, 6.0, 2003R2 and 2003R1.

MSVC_BATCH

When set to any true value, specifies that SCons should batch compilation of object files when calling the Microsoft Visual C++ compiler. All compilations of source files from the same source directory that generate target files in a same output directory and were configured in SCons using the same construction environment will be built in a single call to the compiler. Only source files that have changed since their object files were built will be passed to each compiler invocation (via the $CHANGED_SOURCES construction variable). Any compilations where the object (target) file base name (minus the .obj) does not match the source file base name will be compiled separately.

MSVC_NOTFOUND_POLICY

Specify the scons behavior when the Microsoft Visual C++ compiler is not detected.

The $MSVC_NOTFOUND_POLICY specifies the scons behavior when no msvc versions are detected or when the requested msvc version is not detected.

The valid values for $MSVC_NOTFOUND_POLICY and the corresponding scons behavior are:

'Error' or 'Exception'

Raise an exception when no msvc versions are detected or when the requested msvc version is not detected.

'Warning' or 'Warn'

Issue a warning and continue when no msvc versions are detected or when the requested msvc version is not detected. Depending on usage, this could result in build failure(s).

'Ignore' or 'Suppress'

Take no action and continue when no msvc versions are detected or when the requested msvc version is not detected. Depending on usage, this could result in build failure(s).

Note: in addition to the camel case values shown above, lower case and upper case values are accepted as well.

The $MSVC_NOTFOUND_POLICY is applied when any of the following conditions are satisfied:

• $MSVC_VERSION is specified, the default tools list is implicitly defined (i.e., the tools list is not specified), and the default tools list contains one or more of the msvc tools.
• $MSVC_VERSION is specified, the default tools list is explicitly specified (e.g., tools=['default']), and the default tools list contains one or more of the msvc tools.
• A non-default tools list is specified that contains one or more of the msvc tools (e.g., tools=['msvc', 'mslink']).

The $MSVC_NOTFOUND_POLICY is ignored when any of the following conditions are satisfied:

• $MSVC_VERSION is not specified and the default tools list is implicitly defined (i.e., the tools list is not specified).
• $MSVC_VERSION is not specified and the default tools list is explicitly specified (e.g., tools=['default']).
• A non-default tool list is specified that does not contain any of the msvc tools (e.g., tools=['mingw']).

Important usage details:

• $MSVC_NOTFOUND_POLICY must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_NOTFOUND_POLICY must be set before the first msvc tool is loaded into the environment.

When $MSVC_NOTFOUND_POLICY is not specified, the default scons behavior is to issue a warning and continue subject to the conditions listed above. The default scons behavior may change in the future.

New in version 4.4

MSVC_SCRIPT_ARGS

Pass user-defined arguments to the Microsoft Visual C++ batch file determined via autodetection.

$MSVC_SCRIPT_ARGS is available for msvc batch file arguments that do not have first-class support via construction variables or when there is an issue with the appropriate construction variable validation. When available, it is recommended to use the appropriate construction variables (e.g., $MSVC_TOOLSET_VERSION) rather than $MSVC_SCRIPT_ARGS arguments.

The valid values for $MSVC_SCRIPT_ARGS are: None, a string, or a list of strings.

The $MSVC_SCRIPT_ARGS value is converted to a scalar string (i.e., "flattened"). The resulting scalar string, if not empty, is passed as an argument to the msvc batch file determined via autodetection subject to the validation conditions listed below.

$MSVC_SCRIPT_ARGS is ignored when the value is None and when the result from argument conversion is an empty string. The validation conditions below do not apply.

An exception is raised when any of the following conditions are satisfied:

• $MSVC_SCRIPT_ARGS is specified for Visual Studio 2013 and earlier.
• Multiple SDK version arguments (e.g., '10.0.20348.0') are specified in $MSVC_SCRIPT_ARGS.
• $MSVC_SDK_VERSION is specified and an SDK version argument (e.g., '10.0.20348.0') is specified in $MSVC_SCRIPT_ARGS. Multiple SDK version declarations via $MSVC_SDK_VERSION and $MSVC_SCRIPT_ARGS are not allowed.
• Multiple toolset version arguments (e.g., '-vcvars_ver=14.29') are specified in $MSVC_SCRIPT_ARGS.
• $MSVC_TOOLSET_VERSION is specified and a toolset version argument (e.g., '-vcvars_ver=14.29') is specified in $MSVC_SCRIPT_ARGS. Multiple toolset version declarations via $MSVC_TOOLSET_VERSION and $MSVC_SCRIPT_ARGS are not allowed.
• Multiple spectre library arguments (e.g., '-vcvars_spectre_libs=spectre') are specified in $MSVC_SCRIPT_ARGS.
• $MSVC_SPECTRE_LIBS is enabled and a spectre library argument (e.g., '-vcvars_spectre_libs=spectre') is specified in $MSVC_SCRIPT_ARGS. Multiple spectre library declarations via $MSVC_SPECTRE_LIBS and $MSVC_SCRIPT_ARGS are not allowed.
• Multiple UWP arguments (e.g., uwp or store) are specified in $MSVC_SCRIPT_ARGS.
• $MSVC_UWP_APP is enabled and a UWP argument (e.g., uwp or store) is specified in $MSVC_SCRIPT_ARGS. Multiple UWP declarations via $MSVC_UWP_APP and $MSVC_SCRIPT_ARGS are not allowed.

Example 1 - A Visual Studio 2022 build with an SDK version and a toolset version specified with a string argument:

env = Environment(MSVC_VERSION='14.3', MSVC_SCRIPT_ARGS='10.0.20348.0 -vcvars_ver=14.29.30133')

Example 2 - A Visual Studio 2022 build with an SDK version and a toolset version specified with a list argument:

env = Environment(MSVC_VERSION='14.3', MSVC_SCRIPT_ARGS=['10.0.20348.0', '-vcvars_ver=14.29.30133'])

Important usage details:

• $MSVC_SCRIPT_ARGS must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_SCRIPT_ARGS must be set before the first msvc tool is loaded into the environment.
• Other than checking for multiple declarations as described above, $MSVC_SCRIPT_ARGS arguments are not validated.
• Erroneous, inconsistent, and/or version incompatible $MSVC_SCRIPT_ARGS arguments are likely to result in build failures for reasons that are not readily apparent and may be difficult to diagnose. The burden is on the user to ensure that the arguments provided to the msvc batch file are valid, consistent and compatible with the version of msvc selected.

New in version 4.4

MSVC_SCRIPTERROR_POLICY

Specify the scons behavior when Microsoft Visual C++ batch file errors are detected.

The $MSVC_SCRIPTERROR_POLICY specifies the scons behavior when msvc batch file errors are detected. When $MSVC_SCRIPTERROR_POLICY is not specified, the default scons behavior is to suppress msvc batch file error messages.

The root cause of msvc build failures may be difficult to diagnose. In these situations, setting the scons behavior to issue a warning when msvc batch file errors are detected may produce additional diagnostic information.

The valid values for $MSVC_SCRIPTERROR_POLICY and the corresponding scons behavior are:

'Error' or 'Exception'

Raise an exception when msvc batch file errors are detected.

'Warning' or 'Warn'

Issue a warning when msvc batch file errors are detected.

'Ignore' or 'Suppress'

Suppress msvc batch file error messages.

New in version 4.4

Note: in addition to the camel case values shown above, lower case and upper case values are accepted as well.

Example 1 - A Visual Studio 2022 build with user-defined script arguments:

env = environment(MSVC_VERSION='14.3', MSVC_SCRIPT_ARGS=['8.1', 'store', '-vcvars_ver=14.1'])
env.Program('hello', ['hello.c'], CCFLAGS='/MD', LIBS=['kernel32', 'user32', 'runtimeobject'])

Example 1 - Output fragment:

...
link /nologo /OUT:_build001\hello.exe kernel32.lib user32.lib runtimeobject.lib _build001\hello.obj
LINK : fatal error LNK1104: cannot open file 'MSVCRT.lib'
...

Example 2 - A Visual Studio 2022 build with user-defined script arguments and the script error policy set to issue a warning when msvc batch file errors are detected:

env = environment(MSVC_VERSION='14.3', MSVC_SCRIPT_ARGS=['8.1', 'store', '-vcvars_ver=14.1'], MSVC_SCRIPTERROR_POLICY='warn')
env.Program('hello', ['hello.c'], CCFLAGS='/MD', LIBS=['kernel32', 'user32', 'runtimeobject'])

Example 2 - Output fragment:

...
scons: warning: vc script errors detected:
[ERROR:vcvars.bat] The UWP Application Platform requires a Windows 10 SDK.
[ERROR:vcvars.bat] WindowsSdkDir = "C:\Program Files (x86)\Windows Kits\8.1\"
[ERROR:vcvars.bat] host/target architecture is not supported : { x64 , x64 }
...
link /nologo /OUT:_build001\hello.exe kernel32.lib user32.lib runtimeobject.lib _build001\hello.obj
LINK : fatal error LNK1104: cannot open file 'MSVCRT.lib'

Important usage details:

• $MSVC_SCRIPTERROR_POLICY must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_SCRIPTERROR_POLICY must be set before the first msvc tool is loaded into the environment.
• Due to scons implementation details, not all Windows system environment variables are propagated to the environment in which the msvc batch file is executed. Depending on Visual Studio version and installation options, non-fatal msvc batch file error messages may be generated for ancillary tools which may not affect builds with the msvc compiler. For this reason, caution is recommended when setting the script error policy to raise an exception (e.g., 'Error').

New in version 4.4

MSVC_SDK_VERSION

Build with a specific version of the Microsoft Software Development Kit (SDK).

The valid values for $MSVC_SDK_VERSION are: None or a string containing the requested SDK version (e.g., '10.0.20348.0').

$MSVC_SDK_VERSION is ignored when the value is None and when the value is an empty string. The validation conditions below do not apply.

An exception is raised when any of the following conditions are satisfied:

• $MSVC_SDK_VERSION is specified for Visual Studio 2013 and earlier.
• $MSVC_SDK_VERSION is specified and an SDK version argument is specified in $MSVC_SCRIPT_ARGS. Multiple SDK version declarations via $MSVC_SDK_VERSION and $MSVC_SCRIPT_ARGS are not allowed.

• The $MSVC_SDK_VERSION specified does not match any of the supported formats:

  • '10.0.XXXXX.Y' [SDK 10.0]
  • '8.1' [SDK 8.1]
• The system folder for the corresponding $MSVC_SDK_VERSION version is not found. The requested SDK version does not appear to be installed.
• The $MSVC_SDK_VERSION version does not appear to support the requested platform type (i.e., UWP or Desktop). The requested SDK version platform type components do not appear to be installed.
• The $MSVC_SDK_VERSION version is 8.1, the platform type is UWP, and the build tools selected are from Visual Studio 2017 and later (i.e., $MSVC_VERSION must be '14.0' or $MSVC_TOOLSET_VERSION must be '14.0').

Example 1 - A Visual Studio 2022 build with a specific Windows SDK version:

env = Environment(MSVC_VERSION='14.3', MSVC_SDK_VERSION='10.0.20348.0')

Example 2 - A Visual Studio 2022 build with a specific SDK version for the Universal Windows Platform:

env = Environment(MSVC_VERSION='14.3', MSVC_SDK_VERSION='10.0.20348.0', MSVC_UWP_APP=True)

Important usage details:

• $MSVC_SDK_VERSION must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_SDK_VERSION must be set before the first msvc tool is loaded into the environment.
• Should a SDK 10.0 version be installed that does not follow the naming scheme above, the SDK version will need to be specified via $MSVC_SCRIPT_ARGS until the version number validation format can be extended.
• Should an exception be raised indicating that the SDK version is not found, verify that the requested SDK version is installed with the necessary platform type components.
• There is a known issue with the Microsoft libraries when the target architecture is ARM64 and a Windows 11 SDK (version '10.0.22000.0' and later) is used with the v141 build tools and older v142 toolsets (versions '14.28.29333' and earlier). Should build failures arise with these combinations of settings due to unresolved symbols in the Microsoft libraries, $MSVC_SDK_VERSION may be employed to specify a Windows 10 SDK (e.g., '10.0.20348.0') for the build.

New in version 4.4

MSVC_SPECTRE_LIBS

Build with the spectre-mitigated Microsoft Visual C++ libraries.

The valid values for $MSVC_SPECTRE_LIBS are: True, False, or None.

When $MSVC_SPECTRE_LIBS is enabled (i.e., True), the Microsoft Visual C++ environment will include the paths to the spectre-mitigated implementations of the Microsoft Visual C++ libraries.

An exception is raised when any of the following conditions are satisfied:

• $MSVC_SPECTRE_LIBS is enabled for Visual Studio 2015 and earlier.
• $MSVC_SPECTRE_LIBS is enabled and a spectre library argument is specified in $MSVC_SCRIPT_ARGS. Multiple spectre library declarations via $MSVC_SPECTRE_LIBS and $MSVC_SCRIPT_ARGS are not allowed.
• $MSVC_SPECTRE_LIBS is enabled and the platform type is UWP. There are no spectre-mitigated libraries for Universal Windows Platform (UWP) applications or components.

Example - A Visual Studio 2022 build with spectre mitigated Microsoft Visual C++ libraries:

env = Environment(MSVC_VERSION='14.3', MSVC_SPECTRE_LIBS=True)

Important usage details:

• $MSVC_SPECTRE_LIBS must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_SPECTRE_LIBS must be set before the first msvc tool is loaded into the environment.
• Additional compiler switches (e.g., /Qspectre) are necessary for including spectre mitigations when building user artifacts. Refer to the Visual Studio documentation for details.
• The existence of the spectre libraries host architecture and target architecture folders are not verified when $MSVC_SPECTRE_LIBS is enabled which could result in build failures. The burden is on the user to ensure the requisite libraries with spectre mitigations are installed.

New in version 4.4

MSVC_TOOLSET_VERSION

Build with a specific Microsoft Visual C++ toolset version.

Specifying $MSVC_TOOLSET_VERSION does not affect the autodetection and selection of msvc instances. The $MSVC_TOOLSET_VERSION is applied after an msvc instance is selected. This could be the default version of msvc if $MSVC_VERSION is not specified.

The valid values for $MSVC_TOOLSET_VERSION are: None or a string containing the requested toolset version (e.g., '14.29').

$MSVC_TOOLSET_VERSION is ignored when the value is None and when the value is an empty string. The validation conditions below do not apply.

An exception is raised when any of the following conditions are satisfied:

• $MSVC_TOOLSET_VERSION is specified for Visual Studio 2015 and earlier.
• $MSVC_TOOLSET_VERSION is specified and a toolset version argument is specified in $MSVC_SCRIPT_ARGS. Multiple toolset version declarations via $MSVC_TOOLSET_VERSION and $MSVC_SCRIPT_ARGS are not allowed.

• The $MSVC_TOOLSET_VERSION specified does not match any of the supported formats:

  • 'XX.Y'
  • 'XX.YY'
  • 'XX.YY.ZZZZZ'
  • 'XX.YY.Z' to 'XX.YY.ZZZZ' [scons extension not directly supported by the msvc batch files and may be removed in the future]
  • 'XX.YY.ZZ.N' [SxS format]
  • 'XX.YY.ZZ.NN' [SxS format]
• The major msvc version prefix (i.e., 'XX.Y') of the $MSVC_TOOLSET_VERSION specified is for Visual Studio 2013 and earlier (e.g., '12.0').
• The major msvc version prefix (i.e., 'XX.Y') of the $MSVC_TOOLSET_VERSION specified is greater than the msvc version selected (e.g., '99.0').
• A system folder for the corresponding $MSVC_TOOLSET_VERSION version is not found. The requested toolset version does not appear to be installed.

Toolset selection details:

• When $MSVC_TOOLSET_VERSION is not an SxS version number or a full toolset version number: the first toolset version, ranked in descending order, that matches the $MSVC_TOOLSET_VERSION prefix is selected.

• When $MSVC_TOOLSET_VERSION is specified using the major msvc version prefix (i.e., 'XX.Y') and the major msvc version is that of the latest release of Visual Studio, the selected toolset version may not be the same as the default Microsoft Visual C++ toolset version.

  In the latest release of Visual Studio, the default Microsoft Visual C++ toolset version is not necessarily the toolset with the largest version number.

Example 1 - A default Visual Studio build with a partial toolset version specified:

env = Environment(MSVC_TOOLSET_VERSION='14.2')

Example 2 - A default Visual Studio build with a partial toolset version specified:

env = Environment(MSVC_TOOLSET_VERSION='14.29')

Example 3 - A Visual Studio 2022 build with a full toolset version specified:

env = Environment(MSVC_VERSION='14.3', MSVC_TOOLSET_VERSION='14.29.30133')

Example 4 - A Visual Studio 2022 build with an SxS toolset version specified:

env = Environment(MSVC_VERSION='14.3', MSVC_TOOLSET_VERSION='14.29.16.11')

Important usage details:

• $MSVC_TOOLSET_VERSION must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_TOOLSET_VERSION must be set before the first msvc tool is loaded into the environment.
• The existence of the toolset host architecture and target architecture folders are not verified when $MSVC_TOOLSET_VERSION is specified which could result in build failures. The burden is on the user to ensure the requisite toolset target architecture build tools are installed.

New in version 4.4

MSVC_USE_SCRIPT

Use a batch script to set up the Microsoft Visual C++ compiler.

If set to the name of a Visual Studio .bat file (e.g. vcvars.bat), SCons will run that batch file instead of the auto-detected one, and extract the relevant variables from the result (typically %INCLUDE%, %LIB%, and %PATH%) for supplying to the build. This can be useful to force the use of a compiler version that SCons does not detect. $MSVC_USE_SCRIPT_ARGS provides arguments passed to this script.

Setting $MSVC_USE_SCRIPT to None bypasses the Visual Studio autodetection entirely; use this if you are running SCons in a Visual Studio cmd window and importing the shell's environment variables - that is, if you are sure everything is set correctly already and you don't want SCons to change anything.

$MSVC_USE_SCRIPT ignores $MSVC_VERSION and $TARGET_ARCH.

Changed in version 4.4: new $MSVC_USE_SCRIPT_ARGS provides a way to pass arguments.

MSVC_USE_SCRIPT_ARGS

Provides arguments passed to the script $MSVC_USE_SCRIPT.

New in version 4.4

MSVC_USE_SETTINGS

Use a dictionary to set up the Microsoft Visual C++ compiler.

$MSVC_USE_SETTINGS is ignored when $MSVC_USE_SCRIPT is defined and/or when $MSVC_USE_SETTINGS is set to None.

The dictionary is used to populate the environment with the relevant variables (typically %INCLUDE%, %LIB%, and %PATH%) for supplying to the build. This can be useful to force the use of a compiler environment that SCons does not configure correctly. This is an alternative to manually configuring the environment when bypassing Visual Studio autodetection entirely by setting $MSVC_USE_SCRIPT to None.

Here is an example of configuring a build environment using the Microsoft Visual C++ compiler included in the Microsoft SDK on a 64-bit host and building for a 64-bit architecture:

# Microsoft SDK 6.0 (MSVC 8.0): 64-bit host and 64-bit target
msvc_use_settings = {
    "PATH": [
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\VC\\Bin\\x64",
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\Bin\\x64",
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\Bin",
        "C:\\Windows\\Microsoft.NET\\Framework\\v2.0.50727",
        "C:\\Windows\\system32",
        "C:\\Windows",
        "C:\\Windows\\System32\\Wbem",
        "C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\"
    ],
    "INCLUDE": [
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\VC\\Include",
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\VC\\Include\\Sys",
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\Include",
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\Include\\gl",
    ],
    "LIB": [
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\VC\\Lib\\x64",
        "C:\\Program Files\\Microsoft SDKs\\Windows\\v6.0\\Lib\\x64",
    ],
    "LIBPATH": [],
    "VSCMD_ARG_app_plat": [],
    "VCINSTALLDIR": [],
    "VCToolsInstallDir": []
}

# Specifying MSVC_VERSION is recommended
env = Environment(MSVC_VERSION='8.0', MSVC_USE_SETTINGS=msvc_use_settings)

Important usage details:

• $MSVC_USE_SETTINGS must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_USE_SETTINGS must be set before the first msvc tool is loaded into the environment.
• The dictionary content requirements are based on the internal msvc implementation and therefore may change at any time. The burden is on the user to ensure the dictionary contents are minimally sufficient to ensure successful builds.

New in version 4.4

MSVC_UWP_APP

Build with the Universal Windows Platform (UWP) application Microsoft Visual C++ libraries.

The valid values for $MSVC_UWP_APP are: True, '1', False, '0', or None.

When $MSVC_UWP_APP is enabled (i.e., True or '1'), the Microsoft Visual C++ environment will be set up to point to the Windows Store compatible libraries and Microsoft Visual C++ runtimes. In doing so, any libraries that are built will be able to be used in a UWP App and published to the Windows Store.

An exception is raised when any of the following conditions are satisfied:

• $MSVC_UWP_APP is enabled for Visual Studio 2013 and earlier.
• $MSVC_UWP_APP is enabled and a UWP argument is specified in $MSVC_SCRIPT_ARGS. Multiple UWP declarations via $MSVC_UWP_APP and $MSVC_SCRIPT_ARGS are not allowed.

Example - A Visual Studio 2022 build for the Universal Windows Platform:

env = Environment(MSVC_VERSION='14.3', MSVC_UWP_APP=True)

Important usage details:

• $MSVC_UWP_APP must be passed as an argument to the Environment constructor when an msvc tool (e.g., msvc, msvs, etc.) is loaded via the default tools list or via a tools list passed to the Environment constructor. Otherwise, $MSVC_UWP_APP must be set before the first msvc tool is loaded into the environment.
• The existence of the UWP libraries is not verified when $MSVC_UWP_APP is enabled which could result in build failures. The burden is on the user to ensure the requisite UWP libraries are installed.

MSVC_VERSION

A string to select the preferred version of Microsoft Visual C++. If the specified version is unavailable and/or unknown to SCons, a warning is issued showing the versions actually discovered, and the build will eventually fail indicating a missing compiler binary. If $MSVC_VERSION is not set, SCons will (by default) select the latest version of Microsoft Visual C++ installed on your system (excluding any preview versions).

Note
In order to take effect, $MSVC_VERSION must be set before the initial Microsoft Visual C++ compiler discovery takes place. Discovery happens, at the latest, during the first call to the Environment function, unless a tools list is specified which excludes the entire Microsoft Visual C++ toolchain - that is, omits "defaults" and any specific tool module that refers to parts of the toolchain (msvc, mslink, masm, midl and msvs). In this case, detection is deferred until any one of those tool modules is invoked manually. The following two examples illustrate this:

# MSVC_VERSION set as Environment is created
env = Environment(MSVC_VERSION='14.2')

# Initialization deferred with empty tools, triggered manually
env = Environment(tools=[])
env['MSVC_VERSION'] = '14.2
env.Tool('msvc')
env.Tool('mslink')
env.Tool('msvs')

The valid values for $MSVC_VERSION represent major versions of the compiler, except that versions ending in Exp refer to "Express" or "Express for Desktop" Visual Studio editions. Values that do not look like a valid compiler version string are not supported.

The following table shows the correspondence of $MSVC_VERSION values to various version indicators ('x' is used as a placeholder for a single digit that can vary).

SCons Key	Visual C++ Version	_MSVC_VER	Visual Studio Product	MSBuild / Visual Studio
"14.3"	14.3x	193x	Visual Studio 2022	17.x, 17.1x
"14.2"	14.2x	192x	Visual Studio 2019	16.x, 16.1x
"14.1"	14.1 or 14.1x	191x	Visual Studio 2017	15.x
"14.1Exp"	14.1 or 14.1x	191x	Visual Studio 2017 Express	15.x
"14.0"	14.0	1900	Visual Studio 2015	14.0
"14.0Exp"	14.0	1900	Visual Studio 2015 Express	14.0
"12.0"	12.0	1800	Visual Studio 2013	12.0
"12.0Exp"	12.0	1800	Visual Studio 2013 Express	12.0
"11.0"	11.0	1700	Visual Studio 2012	11.0
"11.0Exp"	11.0	1700	Visual Studio 2012 Express	11.0
"10.0"	10.0	1600	Visual Studio 2010	10.0
"10.0Exp"	10.0	1600	Visual C++ Express 2010	10.0
"9.0"	9.0	1500	Visual Studio 2008	9.0
"9.0Exp"	9.0	1500	Visual C++ Express 2008	9.0
"8.0"	8.0	1400	Visual Studio 2005	8.0
"8.0Exp"	8.0	1400	Visual C++ Express 2005	8.0
"7.1"	7.1	1300	Visual Studio .NET 2003	7.1
"7.0"	7.0	1200	Visual Studio .NET 2002	7.0
"6.0"	6.0	1100	Visual Studio 6.0	6.0

Note

• It is not necessary to install a Visual Studio IDE to build with SCons (for example, you can install only Build Tools), but when a Visual Studio IDE is installed, additional builders such as MSVSSolution and MSVSProject become available and correspond to the specified versions.
• Versions ending in Exp refer to historical "Express" or "Express for Desktop" Visual Studio editions, which had feature limitations compared to the full editions. It is only necessary to specify the Exp suffix to select the express edition when both express and non-express editions of the same product are installed simultaneously. The Exp suffix is unnecessary, but accepted, when only the express edition is installed.

The compilation environment can be further or more precisely specified through the use of several other construction variables: see the descriptions of $MSVC_TOOLSET_VERSION, $MSVC_SDK_VERSION, $MSVC_USE_SCRIPT, $MSVC_USE_SCRIPT_ARGS, and $MSVC_USE_SETTINGS.

MSVS

When the Microsoft Visual Studio tools are initialized, they set up this dictionary with the following keys:

VERSION

the version of MSVS being used (can be set via $MSVC_VERSION)

VERSIONS

the available versions of MSVS installed

VCINSTALLDIR

installed directory of Microsoft Visual C++

VSINSTALLDIR

installed directory of Visual Studio

FRAMEWORKDIR

installed directory of the .NET framework

FRAMEWORKVERSIONS

list of installed versions of the .NET framework, sorted latest to oldest.

FRAMEWORKVERSION

latest installed version of the .NET framework

FRAMEWORKSDKDIR

installed location of the .NET SDK.

PLATFORMSDKDIR

installed location of the Platform SDK.

PLATFORMSDK_MODULES

dictionary of installed Platform SDK modules, where the dictionary keys are keywords for the various modules, and the values are 2-tuples where the first is the release date, and the second is the version number.

If a value is not set, it was not available in the registry. Visual Studio 2017 and later do not use the registry for primary storage of this information, so typically for these versions only PROJECTSUFFIX and SOLUTIONSUFFIX will be set.

MSVS_ARCH

Sets the architecture for which the generated project(s) should build.

The default value is x86. amd64 is also supported by SCons for most Visual Studio versions. Since Visual Studio 2015 arm is supported, and since Visual Studio 2017 arm64 is supported. Trying to set $MSVS_ARCH to an architecture that's not supported for a given Visual Studio version will generate an error.

MSVS_PROJECT_GUID

The string placed in a generated Microsoft Visual C++ project file as the value of the ProjectGUID attribute. There is no default value. If not defined, a new GUID is generated.

MSVS_SCC_AUX_PATH

The path name placed in a generated Microsoft Visual C++ project file as the value of the SccAuxPath attribute if the MSVS_SCC_PROVIDER construction variable is also set. There is no default value.

MSVS_SCC_CONNECTION_ROOT

The root path of projects in your SCC workspace, i.e the path under which all project and solution files will be generated. It is used as a reference path from which the relative paths of the generated Microsoft Visual C++ project and solution files are computed. The relative project file path is placed as the value of the SccLocalPath attribute of the project file and as the values of the SccProjectFilePathRelativizedFromConnection[i] (where [i] ranges from 0 to the number of projects in the solution) attributes of the GlobalSection(SourceCodeControl) section of the Microsoft Visual Studio solution file. Similarly, the relative solution file path is placed as the values of the SccLocalPath[i] (where [i] ranges from 0 to the number of projects in the solution) attributes of the GlobalSection(SourceCodeControl) section of the Microsoft Visual Studio solution file. This is used only if the MSVS_SCC_PROVIDER construction variable is also set. The default value is the current working directory.

MSVS_SCC_PROJECT_NAME

The project name placed in a generated Microsoft Visual C++ project file as the value of the SccProjectName attribute if the MSVS_SCC_PROVIDER construction variable is also set. In this case the string is also placed in the SccProjectName0 attribute of the GlobalSection(SourceCodeControl) section of the Microsoft Visual Studio solution file. There is no default value.

MSVS_SCC_PROVIDER

The string placed in a generated Microsoft Visual C++ project file as the value of the SccProvider attribute. The string is also placed in the SccProvider0 attribute of the GlobalSection(SourceCodeControl) section of the Microsoft Visual Studio solution file. There is no default value.

MSVS_VERSION

Set the preferred version of Microsoft Visual Studio to use.

If $MSVS_VERSION is not set, SCons will (by default) select the latest version of Visual Studio installed on your system. So, if you have version 6 and version 7 (MSVS .NET) installed, it will prefer version 7. You can override this by specifying the $MSVS_VERSION variable when initializing the Environment, setting it to the appropriate version ('6.0' or '7.0', for example). If the specified version isn't installed, tool initialization will fail.

Deprecated since 1.3.0: $MSVS_VERSION is deprecated in favor of $MSVC_VERSION. As a transitional aid, if $MSVS_VERSION is set and $MSVC_VERSION is not, $MSVC_VERSION will be initialized to the value of $MSVS_VERSION. An error is raised if both are set and have different values.

MSVSBUILDCOM

The build command line placed in a generated Microsoft Visual C++ project file. The default is to have Visual Studio invoke SCons with any specified build targets.

MSVSCLEANCOM

The clean command line placed in a generated Microsoft Visual C++ project file. The default is to have Visual Studio invoke SCons with the -c option to remove any specified targets.

MSVSENCODING

The encoding string placed in a generated Microsoft Visual C++ project file. The default is encoding Windows-1252.

MSVSPROJECTCOM

The action used to generate Microsoft Visual C++ project files.

MSVSPROJECTSUFFIX

The suffix used for Microsoft Visual C++ project (DSP) files. The default value is .vcxproj when using Visual Studio 2010 and later, .vcproj when using Visual Studio versions between 2002 and 2008, and .dsp when using Visual Studio 6.0.

MSVSREBUILDCOM

The rebuild command line placed in a generated Microsoft Visual C++ project file. The default is to have Visual Studio invoke SCons with any specified rebuild targets.

MSVSSCONS

The SCons used in generated Microsoft Visual C++ project files. The default is the version of SCons being used to generate the project file.

MSVSSCONSCOM

The default SCons command used in generated Microsoft Visual C++ project files.

MSVSSCONSCRIPT

The sconscript file (that is, SConstruct or SConscript file) that will be invoked by Microsoft Visual C++ project files (through the $MSVSSCONSCOM variable). The default is the same sconscript file that contains the call to MSVSProject to build the project file.

MSVSSCONSFLAGS

The SCons flags used in generated Microsoft Visual C++ project files.

MSVSSOLUTIONCOM

The action used to generate Microsoft Visual Studio solution files.

MSVSSOLUTIONSUFFIX

The suffix used for Microsoft Visual Studio solution (DSW) files. The default value is .sln when using Visual Studio version 7.x (.NET 2002) and later, and .dsw when using Visual Studio 6.0.

MT

The program used on Windows systems to embed manifests into DLLs and EXEs. See also $WINDOWS_EMBED_MANIFEST.

MTEXECOM

The Windows command line used to embed manifests into executables. See also $MTSHLIBCOM.

MTFLAGS

Flags passed to the $MT manifest embedding program (Windows only).

MTSHLIBCOM

The Windows command line used to embed manifests into shared libraries (DLLs). See also $MTEXECOM.

MWCW_VERSION

The version number of the MetroWerks CodeWarrior C compiler to be used.

MWCW_VERSIONS

A list of installed versions of the MetroWerks CodeWarrior C compiler on this system.

NAME

Specfies the name of the project to package.

See the Package builder.

NINJA_ALIAS_NAME

The name of the alias target which will cause SCons to create the ninja build file, and then (optionally) run ninja. The default value is generate-ninja.

NINJA_CMD_ARGS

A string which will pass arguments through SCons to the ninja command when scons executes ninja. Has no effect if $NINJA_DISABLE_AUTO_RUN is set.

This value can also be passed on the command line:

scons NINJA_CMD_ARGS=-v
or
scons NINJA_CMD_ARGS="-v -j 3"

NINJA_COMPDB_EXPAND

Boolean value to instruct ninja to expand the command line arguments normally put into response files. If true, prevents unexpanded lines in the compilation database like “gcc @rsp_file” and instead yields expanded lines like “gcc -c -o myfile.o myfile.c -Ia -DXYZ”.

Ninja's compdb tool added the -x flag in Ninja V1.9.0

NINJA_DEPFILE_PARSE_FORMAT

Determines the type of format ninja should expect when parsing header include depfiles. Can be msvc, gcc, or clang. The msvc option corresponds to /showIncludes format, and gcc or clang correspond to -MMD -MF.

NINJA_DIR

The builddir value. Propagates directly into the generated ninja build file. From Ninja's docs: “ A directory for some Ninja output files. ... (You can also store other build output in this directory.) ” The default value is .ninja.

NINJA_DISABLE_AUTO_RUN

Boolean. Default: False. If true, SCons will not run ninja automatically after creating the ninja build file.

If not explicitly set, this will be set to True if --disable_execute_ninja or SetOption('disable_execute_ninja', True) is seen.

NINJA_ENV_VAR_CACHE

A string that sets the environment for any environment variables that differ between the OS environment and the SCons execution environment.

It will be compatible with the default shell of the operating system.

If not explicitly set, SCons will generate this dynamically from the execution environment stored in the current construction environment (e.g. env['ENV']) where those values differ from the existing shell..

NINJA_FILE_NAME

The filename for the generated Ninja build file. The default is ninja.build.

NINJA_FORCE_SCONS_BUILD

If true, causes the build nodes to call back to scons instead of using ninja to build them. This is intended to be passed to the environment on the builder invocation. It is useful if you have a build node which does something which is not easily translated into ninja.

NINJA_GENERATED_SOURCE_ALIAS_NAME

A string matching the name of a user defined alias which represents a list of all generated sources. This will prevent the auto-detection of generated sources from $NINJA_GENERATED_SOURCE_SUFFIXES. Then all other source files will be made to depend on this in the ninja build file, forcing the generated sources to be built first.

NINJA_GENERATED_SOURCE_SUFFIXES

The list of source file suffixes which are generated by SCons build steps. All source files which match these suffixes will be added to the _generated_sources alias in the output ninja build file. Then all other source files will be made to depend on this in the ninja build file, forcing the generated sources to be built first.

NINJA_MSVC_DEPS_PREFIX

The msvc_deps_prefix string. Propagates directly into the generated ninja build file. From Ninja's docs: “defines the string which should be stripped from msvc's /showIncludes output”

NINJA_POOL

Set the ninja_pool for this or all targets in scope for this env var.

NINJA_REGENERATE_DEPS

A generator function used to create a ninja depfile which includes all the files which would require SCons to be invoked if they change. Or a list of said files.

_NINJA_REGENERATE_DEPS_FUNC

Internal value used to specify the function to call with argument env to generate the list of files which, if changed, would require the ninja build file to be regenerated.

NINJA_SCONS_DAEMON_KEEP_ALIVE

The number of seconds for the SCons daemon launched by ninja to stay alive. (Default: 180000)

NINJA_SCONS_DAEMON_PORT

The TCP/IP port for the SCons daemon to listen on. NOTE: You cannot use a port already being listened to on your build machine. (Default: random number between 10000,60000)

NINJA_SYNTAX

The path to a custom ninja_syntax.py file which is used in generation. The tool currently assumes you have ninja installed as a Python module and grabs the syntax file from that installation if $NINJA_SYNTAX is not explicitly set.

no_import_lib

When set to non-zero, suppresses creation of a corresponding Windows static import lib by the SharedLibrary builder when used with MinGW, Microsoft Visual Studio or Metrowerks. This also suppresses creation of an export (.exp) file when using Microsoft Visual Studio.

OBJPREFIX

The prefix used for (static) object file names.

OBJSUFFIX

The suffix used for (static) object file names.

PACKAGEROOT

Specifies the directory where all files in resulting archive will be placed if applicable. The default value is “$NAME-$VERSION”.

See the Package builder.

PACKAGETYPE

Selects the package type to build when using the Package builder. It may be a string or list of strings. See the documentation for the builder for the currently supported types.

$PACKAGETYPE may be overridden with the --package-type command line option.

See the Package builder.

PACKAGEVERSION

The version of the package (not the underlying project). This is currently only used by the rpm packager and should reflect changes in the packaging, not the underlying project code itself.

See the Package builder.

PCH

A node for the Microsoft Visual C++ precompiled header that will be used when compiling object files. This variable is ignored by tools other than Microsoft Visual C++. When this variable is defined, SCons will add options to the compiler command line to cause it to use the precompiled header, and will also set up the dependencies for the PCH file. Examples:

env['PCH'] = File('StdAfx.pch')
env['PCH'] = env.PCH('pch.cc')[0]

PCHCOM

The command line used by the PCH builder to generated a precompiled header.

PCHCOMSTR

The string displayed when generating a precompiled header. If not set, then $PCHCOM (the command line) is displayed.

PCHPDBFLAGS

A construction variable that, when expanded, adds the /yD flag to the command line only if the $PDB construction variable is set.

PCHSTOP

This variable specifies how much of a source file is precompiled. This variable is ignored by tools other than Microsoft Visual C++, or when the PCH variable is not being used. When this variable is defined, it must be a string that is the name of the header that is included at the end of the precompiled portion of the source files, or the empty string if the "#pragma hrdstop" construct is being used:

env['PCHSTOP'] = 'StdAfx.h'

PDB

The Microsoft Visual C++ PDB file that will store debugging information for object files, shared libraries, and programs. This variable is ignored by tools other than Microsoft Visual C++. When this variable is defined SCons will add options to the compiler and linker command line to cause them to generate external debugging information, and will also set up the dependencies for the PDB file. Example:

env['PDB'] = 'hello.pdb'

The Microsoft Visual C++ compiler switch that SCons uses by default to generate PDB information is /Z7. This works correctly with parallel (-j) builds because it embeds the debug information in the intermediate object files, as opposed to sharing a single PDB file between multiple object files. This is also the only way to get debug information embedded into a static library. Using the /Zi instead may yield improved link-time performance, although parallel builds will no longer work. You can generate PDB files with the /Zi switch by overriding the default $CCPDBFLAGS variable; see the entry for that variable for specific examples.

PDFLATEX

The pdflatex utility.

PDFLATEXCOM

The command line used to call the pdflatex utility.

PDFLATEXCOMSTR

The string displayed when calling the pdflatex utility. If this is not set, then $PDFLATEXCOM (the command line) is displayed.

env = Environment(PDFLATEX;COMSTR = "Building $TARGET from LaTeX input $SOURCES")

PDFLATEXFLAGS

General options passed to the pdflatex utility.

PDFPREFIX

The prefix used for PDF file names.

PDFSUFFIX

The suffix used for PDF file names.

PDFTEX

The pdftex utility.

PDFTEXCOM

The command line used to call the pdftex utility.

PDFTEXCOMSTR

The string displayed when calling the pdftex utility. If this is not set, then $PDFTEXCOM (the command line) is displayed.

env = Environment(PDFTEXCOMSTR = "Building $TARGET from TeX input $SOURCES")

PDFTEXFLAGS

General options passed to the pdftex utility.

PKGCHK

On Solaris systems, the package-checking program that will be used (along with $PKGINFO) to look for installed versions of the Sun PRO C++ compiler. The default is /usr/sbin/pgkchk.

PKGINFO

On Solaris systems, the package information program that will be used (along with $PKGCHK) to look for installed versions of the Sun PRO C++ compiler. The default is pkginfo.

PLATFORM

The name of the platform used to create this construction environment. SCons sets this when initializing the platform, which by default is auto-detected (see the platform argument to Environment).

env = Environment(tools=[])
if env['PLATFORM'] == 'cygwin':
    Tool('mingw')(env)
else:
    Tool('msvc')(env)

POAUTOINIT

The $POAUTOINIT variable, if set to True (on non-zero numeric value), let the msginit tool to automatically initialize missing PO files with msginit(1). This applies to both, POInit and POUpdate builders (and others that use any of them).

POCREATE_ALIAS

Common alias for all PO files created with POInit builder (default: 'po-create'). See msginit tool and POInit builder.

POSUFFIX

Suffix used for PO files (default: '.po') See msginit tool and POInit builder.

POTDOMAIN

The $POTDOMAIN defines default domain, used to generate POT filename as $POTDOMAIN.pot when no POT file name is provided by the user. This applies to POTUpdate, POInit and POUpdate builders (and builders, that use them, e.g. Translate). Normally (if $POTDOMAIN is not defined), the builders use messages.pot as default POT file name.

POTSUFFIX

Suffix used for PO Template files (default: '.pot'). See xgettext tool and POTUpdate builder.

POTUPDATE_ALIAS

Name of the common phony target for all PO Templates created with POUpdate (default: 'pot-update'). See xgettext tool and POTUpdate builder.

POUPDATE_ALIAS

Common alias for all PO files being defined with POUpdate builder (default: 'po-update'). See msgmerge tool and POUpdate builder.

PRINT_CMD_LINE_FUNC

A Python function used to print the command lines as they are executed (assuming command printing is not disabled by the -q or -s options or their equivalents). The function must accept four arguments: s, target, source and env. s is a string showing the command being executed, target, is the target being built (file node, list, or string name(s)), source, is the source(s) used (file node, list, or string name(s)), and env is the environment being used.

The function must do the printing itself. The default implementation, used if this variable is not set or is None, is to just print the string, as in:

def print_cmd_line(s, target, source, env):
    sys.stdout.write(s + "\n")

Here is an example of a more interesting function:

def print_cmd_line(s, target, source, env):
    sys.stdout.write(
        "Building %s -> %s...\n"
        % (
            ' and '.join([str(x) for x in source]),
            ' and '.join([str(x) for x in target]),
        )
    )

env = Environment(PRINT_CMD_LINE_FUNC=print_cmd_line)
env.Program('foo', ['foo.c', 'bar.c'])

This prints:

...
scons: Building targets ...
Building bar.c -> bar.o...
Building foo.c -> foo.o...
Building foo.o and bar.o -> foo...
scons: done building targets.

Another example could be a function that logs the actual commands to a file.

PROGEMITTER

Contains the emitter specification for the Program builder. The manpage section "Builder Objects" contains general information on specifying emitters.

PROGPREFIX

The prefix used for executable file names.

PROGSUFFIX

The suffix used for executable file names.

PSCOM

The command line used to convert TeX DVI files into a PostScript file.

PSCOMSTR

The string displayed when a TeX DVI file is converted into a PostScript file. If this is not set, then $PSCOM (the command line) is displayed.

PSPREFIX

The prefix used for PostScript file names.

PSSUFFIX

The prefix used for PostScript file names.

QT3_AUTOSCAN

Turn off scanning for mocable files. Use the Moc Builder to explicitly specify files to run moc on.

Changed in 4.5.0: renamed from QT_AUTOSCAN.

QT3_BINPATH

The path where the Qt binaries are installed. The default value is '$QT3DIR/bin'.

Changed in 4.5.0: renamed from QT_BINPATH.

QT3_CPPPATH

The path where the Qt header files are installed. The default value is '$QT3DIR/include'. Note: If you set this variable to None, the tool won't change the $CPPPATH construction variable.

Changed in 4.5.0: renamed from QT_CPPPATH.

QT3_DEBUG

Prints lots of debugging information while scanning for moc files.

Changed in 4.5.0: renamed from QT_DEBUG.

QT3_LIB

Default value is 'qt'. You may want to set this to 'qt-mt'. Note: If you set this variable to None, the tool won't change the $LIBS variable.

Changed in 4.5.0: renamed from QT_LIB.

QT3_LIBPATH

The path where the Qt libraries are installed. The default value is '$QT3DIR/lib'. Note: If you set this variable to None, the tool won't change the $LIBPATH construction variable.

Changed in 4.5.0: renamed from QT_LIBPATH.

QT3_MOC

Default value is '$QT3_BINPATH/moc'.

QT3_MOCCXXPREFIX

Default value is ''. Prefix for moc output files when source is a C++ file.

QT3_MOCCXXSUFFIX

Default value is '.moc'. Suffix for moc output files when source is a C++ file.

Changed in 4.5.0: renamed from QT_MOCCXXSUFFIX.

QT3_MOCFROMCXXCOM

Command to generate a moc file from a C++ file.

Changed in 4.5.0: renamed from QT_MOCFROMCXXCOM.

QT3_MOCFROMCXXCOMSTR

The string displayed when generating a moc file from a C++ file. If this is not set, then $QT3_MOCFROMCXXCOM (the command line) is displayed.

Changed in 4.5.0: renamed from QT_MOCFROMCXXCOMSTR.

QT3_MOCFROMCXXFLAGS

Default value is '-i'. These flags are passed to moc when moccing a C++ file.

Changed in 4.5.0: renamed from QT_MOCFROMCXXFLAGS.

QT3_MOCFROMHCOM

Command to generate a moc file from a header.

Changed in 4.5.0: renamed from QT_MOCFROMSHCOM.

QT3_MOCFROMHCOMSTR

The string displayed when generating a moc file from a C++ file. If this is not set, then $QT3_MOCFROMHCOM (the command line) is displayed.

Changed in 4.5.0: renamed from QT_MOCFROMSHCOMSTR.

QT3_MOCFROMHFLAGS

Default value is ''. These flags are passed to moc when moccing a header file.

Changed in 4.5.0: renamed from QT_MOCFROMSHFLAGS.

QT3_MOCHPREFIX

Default value is 'moc_'. Prefix for moc output files when source is a header.

Changed in 4.5.0: renamed from QT_MOCHPREFIX.

QT3_MOCHSUFFIX

Default value is '$CXXFILESUFFIX'. Suffix for moc output files when source is a header.

Changed in 4.5.0: renamed from QT_MOCHSUFFIX.

QT3_UIC

Default value is '$QT3_BINPATH/uic'.

Changed in 4.5.0: renamed from QT_UIC.

QT3_UICCOM

Command to generate header files from .ui files.

Changed in 4.5.0: renamed from QT_UICCOM.

QT3_UICCOMSTR

The string displayed when generating header files from .ui files. If this is not set, then $QT3_UICCOM (the command line) is displayed.

Changed in 4.5.0: renamed from QT_UICCOMSTR.

QT3_UICDECLFLAGS

Default value is ''. These flags are passed to uic when creating a header file from a .ui file.

Changed in 4.5.0: renamed from QT_UICDECLFLAGS.

QT3_UICDECLPREFIX

Default value is ''. Prefix for uic generated header files.

Changed in 4.5.0: renamed from QT_UICDECLPREFIX.

QT3_UICDECLSUFFIX

Default value is '.h'. Suffix for uic generated header files.

Changed in 4.5.0: renamed from QT_UICDECLSUFFIX.

QT3_UICIMPLFLAGS

Default value is ''. These flags are passed to uic when creating a C++ file from a .ui file.

Changed in 4.5.0: renamed from QT_UICIMPFLAGS.

QT3_UICIMPLPREFIX

Default value is 'uic_'. Prefix for uic generated implementation files.

Changed in 4.5.0: renamed from QT_UICIMPLPREFIX.

QT3_UICIMPLSUFFIX

Default value is '$CXXFILESUFFIX'. Suffix for uic generated implementation files.

Changed in 4.5.0: renamed from QT_UICIMPLSUFFIX.

QT3_UISUFFIX

Default value is '.ui'. Suffix of designer input files.

Changed in 4.5.0: renamed from QT_UISUFFIX.

QT3DIR

The path to the Qt installation to build against. If not already set, qt3 tool tries to obtain this from os.environ; if not found there, it tries to make a guess.

Changed in 4.5.0: renamed from QTDIR.

RANLIB

The archive indexer.

RANLIBCOM

The command line used to index a static library archive.

RANLIBCOMSTR

The string displayed when a static library archive is indexed. If this is not set, then $RANLIBCOM (the command line) is displayed.

env = Environment(RANLIBCOMSTR = "Indexing $TARGET")

RANLIBFLAGS

General options passed to the archive indexer.

RC

The resource compiler used to build a Microsoft Visual C++ resource file.

RCCOM

The command line used to build a Microsoft Visual C++ resource file.

RCCOMSTR

The string displayed when invoking the resource compiler to build a Microsoft Visual C++ resource file. If this is not set, then $RCCOM (the command line) is displayed.

RCFLAGS

The flags passed to the resource compiler by the RES builder.

RCINCFLAGS

An automatically-generated construction variable containing the command-line options for specifying directories to be searched by the resource compiler. The value of $RCINCFLAGS is created by respectively prepending and appending $RCINCPREFIX and $RCINCSUFFIX to the beginning and end of each directory in $CPPPATH.

RCINCPREFIX

The prefix (flag) used to specify an include directory on the resource compiler command line. This will be prepended to the beginning of each directory in the $CPPPATH construction variable when the $RCINCFLAGS variable is expanded.

RCINCSUFFIX

The suffix used to specify an include directory on the resource compiler command line. This will be appended to the end of each directory in the $CPPPATH construction variable when the $RCINCFLAGS variable is expanded.

RDirs

A function that converts a string into a list of Dir instances by searching the repositories.

REGSVR

The program used on Windows systems to register a newly-built DLL library whenever the SharedLibrary builder is passed a keyword argument of register=True.

REGSVRCOM

The command line used on Windows systems to register a newly-built DLL library whenever the SharedLibrary builder is passed a keyword argument of register=True.

REGSVRCOMSTR

The string displayed when registering a newly-built DLL file. If this is not set, then $REGSVRCOM (the command line) is displayed.

REGSVRFLAGS

Flags passed to the DLL registration program on Windows systems when a newly-built DLL library is registered. By default, this includes the /s that prevents dialog boxes from popping up and requiring user attention.

RMIC

The Java RMI stub compiler.

RMICCOM

The command line used to compile stub and skeleton class files from Java classes that contain RMI implementations. Any options specified in the $RMICFLAGS construction variable are included on this command line.

RMICCOMSTR

The string displayed when compiling stub and skeleton class files from Java classes that contain RMI implementations. If this is not set, then $RMICCOM (the command line) is displayed.

env = Environment(
    RMICCOMSTR="Generating stub/skeleton class files $TARGETS from $SOURCES"
)

RMICFLAGS

General options passed to the Java RMI stub compiler.

RPATH

A list of paths to search for shared libraries when running programs. Currently only used in the GNU (gnulink), IRIX (sgilink) and Sun (sunlink) linkers. Ignored on platforms and toolchains that don't support it. Note that the paths added to RPATH are not transformed by scons in any way: if you want an absolute path, you must make it absolute yourself.

_RPATH

An automatically-generated construction variable containing the rpath flags to be used when linking a program with shared libraries. The value of $_RPATH is created by respectively prepending $RPATHPREFIX and appending $RPATHSUFFIX to the beginning and end of each directory in $RPATH.

RPATHPREFIX

The prefix used to specify a directory to be searched for shared libraries when running programs. This will be prepended to the beginning of each directory in the $RPATH construction variable when the $_RPATH variable is automatically generated.

RPATHSUFFIX

The suffix used to specify a directory to be searched for shared libraries when running programs. This will be appended to the end of each directory in the $RPATH construction variable when the $_RPATH variable is automatically generated.

RPCGEN

The RPC protocol compiler.

RPCGENCLIENTFLAGS

Options passed to the RPC protocol compiler when generating client side stubs. These are in addition to any flags specified in the $RPCGENFLAGS construction variable.

RPCGENFLAGS

General options passed to the RPC protocol compiler.

RPCGENHEADERFLAGS

Options passed to the RPC protocol compiler when generating a header file. These are in addition to any flags specified in the $RPCGENFLAGS construction variable.

RPCGENSERVICEFLAGS

Options passed to the RPC protocol compiler when generating server side stubs. These are in addition to any flags specified in the $RPCGENFLAGS construction variable.

RPCGENXDRFLAGS

Options passed to the RPC protocol compiler when generating XDR routines. These are in addition to any flags specified in the $RPCGENFLAGS construction variable.

SCANNERS

A list of the available implicit dependency scanners. New file scanners may be added by appending to this list, although the more flexible approach is to associate scanners with a specific Builder. See the manpage sections "Builder Objects" and "Scanner Objects" for more information.

SCONS_HOME

The (optional) path to the SCons library directory, initialized from the external environment. If set, this is used to construct a shorter and more efficient search path in the $MSVSSCONS command line executed from C++ project files.

SHCC

The C compiler used for generating shared-library objects. See also $CC for compiling to static objects.

SHCCCOM

The command line used to compile a C source file to a shared-library object file. Any options specified in the $SHCFLAGS, $SHCCFLAGS and $CPPFLAGS construction variables are included on this command line. See also $CCCOM for compiling to static objects.

SHCCCOMSTR

If set, the string displayed when a C source file is compiled to a shared object file. If not set, then $SHCCCOM (the command line) is displayed. See also $CCCOMSTR for compiling to static objects.

env = Environment(SHCCCOMSTR = "Compiling shared object $TARGET")

SHCCFLAGS

Options that are passed to the C and C++ compilers to generate shared-library objects. See also $CCFLAGS for compiling to static objects.

SHCFLAGS

Options that are passed to the C compiler (only; not C++) to generate shared-library objects. See also $CFLAGS for compiling to static objects.

SHCXX

The C++ compiler used for generating shared-library objects. See also $CXX for compiling to static objects.

SHCXXCOM

The command line used to compile a C++ source file to a shared-library object file. Any options specified in the $SHCXXFLAGS and $CPPFLAGS construction variables are included on this command line. See also $CXXCOM for compiling to static objects.

SHCXXCOMSTR

If set, the string displayed when a C++ source file is compiled to a shared object file. If not set, then $SHCXXCOM (the command line) is displayed. See also $CXXCOMSTR for compiling to static objects.

env = Environment(SHCXXCOMSTR = "Compiling shared object $TARGET")

SHCXXFLAGS

Options that are passed to the C++ compiler to generate shared-library objects. See also $CXXFLAGS for compiling to static objects.

SHDC

The name of the compiler to use when compiling D source destined to be in a shared object. See also $DC for compiling to static objects.

SHDCOM

The command line to use when compiling code to be part of shared objects. See also $DCOM for compiling to static objects.

SHDCOMSTR

If set, the string displayed when a D source file is compiled to a (shared) object file. If not set, then $SHDCOM (the command line) is displayed. See also $DCOMSTR for compiling to static objects.

SHDLIBVERSIONFLAGS

Extra flags added to $SHDLINKCOM when building versioned SharedLibrary. These flags are only used when $SHLIBVERSION is set.

SHDLINK

The linker to use when creating shared objects for code bases include D sources. See also $DLINK for linking static objects.

SHDLINKCOM

The command line to use when generating shared objects. See also $DLINKCOM for linking static objects.

SHDLINKFLAGS

The list of flags to use when generating a shared object. See also $DLINKFLAGS for linking static objects.

SHELL

A string naming the shell program that will be passed to the $SPAWN function. See the $SPAWN construction variable for more information.

SHELL_ENV_GENERATORS

A hook allowing the execution environment to be modified prior to the actual execution of a command line from an action via the spawner function defined by $SPAWN. Allows substitution based on targets and sources, as well as values from the construction environment, adding extra environment variables, etc.

The value must be a list (or other iterable) of functions which each generate or alter the execution environment dictionary. The first function will be passed a copy of the initial execution environment ($ENV in the current construction environment); the dictionary returned by that function is passed to the next, until the iterable is exhausted and the result returned for use by the command spawner. The original execution environment is not modified.

Each function provided in $SHELL_ENV_GENERATORS must accept four arguments and return a dictionary: env is the construction environment for this action; target is the list of targets associated with this action; source is the list of sources associated with this action; and shell_env is the current dictionary after iterating any previous $SHELL_ENV_GENERATORS functions (this can be compared to the original execution environment, which is available as env['ENV'], to detect any changes).

Example:

def custom_shell_env(env, target, source, shell_env):
    """customize shell_env if desired"""
    if str(target[0]) == 'special_target':
        shell_env['SPECIAL_VAR'] = env.subst('SOME_VAR', target=target, source=source)
    return shell_env

env["SHELL_ENV_GENERATORS"] = [custom_shell_env]

Available since 4.4

SHF03

The Fortran 03 compiler used for generating shared-library objects. You should normally set the $SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $SHF03 if you need to use a specific compiler or compiler version for Fortran 03 files.

SHF03COM

The command line used to compile a Fortran 03 source file to a shared-library object file. You only need to set $SHF03COM if you need to use a specific command line for Fortran 03 files. You should normally set the $SHFORTRANCOM variable, which specifies the default command line for all Fortran versions.

SHF03COMSTR

If set, the string displayed when a Fortran 03 source file is compiled to a shared-library object file. If not set, then $SHF03COM or $SHFORTRANCOM (the command line) is displayed.

SHF03FLAGS

Options that are passed to the Fortran 03 compiler to generated shared-library objects. You only need to set $SHF03FLAGS if you need to define specific user options for Fortran 03 files. You should normally set the $FORTRANCOMMONFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

SHF03PPCOM

The command line used to compile a Fortran 03 source file to a shared-library object file after first running the file through the C preprocessor. Any options specified in the $SHF03FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $SHF03PPCOM if you need to use a specific C-preprocessor command line for Fortran 03 files. You should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

SHF03PPCOMSTR

If set, the string displayed when a Fortran 03 source file is compiled to a shared-library object file after first running the file through the C preprocessor. If not set, then $SHF03PPCOM or $SHFORTRANPPCOM (the command line) is displayed.

SHF08

The Fortran 08 compiler used for generating shared-library objects. You should normally set the $SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $SHF08 if you need to use a specific compiler or compiler version for Fortran 08 files.

SHF08COM

The command line used to compile a Fortran 08 source file to a shared-library object file. You only need to set $SHF08COM if you need to use a specific command line for Fortran 08 files. You should normally set the $SHFORTRANCOM variable, which specifies the default command line for all Fortran versions.

SHF08COMSTR

If set, the string displayed when a Fortran 08 source file is compiled to a shared-library object file. If not set, then $SHF08COM or $SHFORTRANCOM (the command line) is displayed.

SHF08FLAGS

Options that are passed to the Fortran 08 compiler to generated shared-library objects. You only need to set $SHF08FLAGS if you need to define specific user options for Fortran 08 files. You should normally set the $FORTRANCOMMONFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

SHF08PPCOM

The command line used to compile a Fortran 08 source file to a shared-library object file after first running the file through the C preprocessor. Any options specified in the $SHF08FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $SHF08PPCOM if you need to use a specific C-preprocessor command line for Fortran 08 files. You should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

SHF08PPCOMSTR

If set, the string displayed when a Fortran 08 source file is compiled to a shared-library object file after first running the file through the C preprocessor. If not set, then $SHF08PPCOM or $SHFORTRANPPCOM (the command line) is displayed.

SHF77

The Fortran 77 compiler used for generating shared-library objects. You should normally set the $SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $SHF77 if you need to use a specific compiler or compiler version for Fortran 77 files.

SHF77COM

The command line used to compile a Fortran 77 source file to a shared-library object file. You only need to set $SHF77COM if you need to use a specific command line for Fortran 77 files. You should normally set the $SHFORTRANCOM variable, which specifies the default command line for all Fortran versions.

SHF77COMSTR

If set, the string displayed when a Fortran 77 source file is compiled to a shared-library object file. If not set, then $SHF77COM or $SHFORTRANCOM (the command line) is displayed.

SHF77FLAGS

Options that are passed to the Fortran 77 compiler to generated shared-library objects. You only need to set $SHF77FLAGS if you need to define specific user options for Fortran 77 files. You should normally set the $FORTRANCOMMONFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

SHF77PPCOM

The command line used to compile a Fortran 77 source file to a shared-library object file after first running the file through the C preprocessor. Any options specified in the $SHF77FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $SHF77PPCOM if you need to use a specific C-preprocessor command line for Fortran 77 files. You should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

SHF77PPCOMSTR

If set, the string displayed when a Fortran 77 source file is compiled to a shared-library object file after first running the file through the C preprocessor. If not set, then $SHF77PPCOM or $SHFORTRANPPCOM (the command line) is displayed.

SHF90

The Fortran 90 compiler used for generating shared-library objects. You should normally set the $SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $SHF90 if you need to use a specific compiler or compiler version for Fortran 90 files.

SHF90COM

The command line used to compile a Fortran 90 source file to a shared-library object file. You only need to set $SHF90COM if you need to use a specific command line for Fortran 90 files. You should normally set the $SHFORTRANCOM variable, which specifies the default command line for all Fortran versions.

SHF90COMSTR

If set, the string displayed when a Fortran 90 source file is compiled to a shared-library object file. If not set, then $SHF90COM or $SHFORTRANCOM (the command line) is displayed.

SHF90FLAGS

Options that are passed to the Fortran 90 compiler to generated shared-library objects. You only need to set $SHF90FLAGS if you need to define specific user options for Fortran 90 files. You should normally set the $FORTRANCOMMONFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

SHF90PPCOM

The command line used to compile a Fortran 90 source file to a shared-library object file after first running the file through the C preprocessor. Any options specified in the $SHF90FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $SHF90PPCOM if you need to use a specific C-preprocessor command line for Fortran 90 files. You should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

SHF90PPCOMSTR

If set, the string displayed when a Fortran 90 source file is compiled to a shared-library object file after first running the file through the C preprocessor. If not set, then $SHF90PPCOM or $SHFORTRANPPCOM (the command line) is displayed.

SHF95

The Fortran 95 compiler used for generating shared-library objects. You should normally set the $SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You only need to set $SHF95 if you need to use a specific compiler or compiler version for Fortran 95 files.

SHF95COM

The command line used to compile a Fortran 95 source file to a shared-library object file. You only need to set $SHF95COM if you need to use a specific command line for Fortran 95 files. You should normally set the $SHFORTRANCOM variable, which specifies the default command line for all Fortran versions.

SHF95COMSTR

If set, the string displayed when a Fortran 95 source file is compiled to a shared-library object file. If not set, then $SHF95COM or $SHFORTRANCOM (the command line) is displayed.

SHF95FLAGS

Options that are passed to the Fortran 95 compiler to generated shared-library objects. You only need to set $SHF95FLAGS if you need to define specific user options for Fortran 95 files. You should normally set the $FORTRANCOMMONFLAGS variable, which specifies the user-specified options passed to the default Fortran compiler for all Fortran versions.

SHF95PPCOM

The command line used to compile a Fortran 95 source file to a shared-library object file after first running the file through the C preprocessor. Any options specified in the $SHF95FLAGS and $CPPFLAGS construction variables are included on this command line. You only need to set $SHF95PPCOM if you need to use a specific C-preprocessor command line for Fortran 95 files. You should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor command line for all Fortran versions.

SHF95PPCOMSTR

If set, the string displayed when a Fortran 95 source file is compiled to a shared-library object file after first running the file through the C preprocessor. If not set, then $SHF95PPCOM or $SHFORTRANPPCOM (the command line) is displayed.

SHFORTRAN

The default Fortran compiler used for generating shared-library objects.

SHFORTRANCOM

The command line used to compile a Fortran source file to a shared-library object file. By default, any options specified in the $SHFORTRANFLAGS, $_FORTRANMODFLAG, and $_FORTRANINCFLAGS construction variables are included on this command line. See also $FORTRANCOM.

SHFORTRANCOMSTR

If set, the string displayed when a Fortran source file is compiled to a shared-library object file. If not set, then $SHFORTRANCOM (the command line) is displayed.

SHFORTRANFLAGS

Options that are passed to the Fortran compiler to generate shared-library objects.

SHFORTRANPPCOM

The command line used to compile a Fortran source file to a shared-library object file after first running the file through the C preprocessor. By default, any options specified in the $SHFORTRANFLAGS, $CPPFLAGS, $_CPPDEFFLAGS, $_FORTRANMODFLAG, and $_FORTRANINCFLAGS construction variables are included on this command line. See also $SHFORTRANCOM.

SHFORTRANPPCOMSTR

If set, the string displayed when a Fortran source file is compiled to a shared-library object file after first running the file through the C preprocessor. If not set, then $SHFORTRANPPCOM (the command line) is displayed.

SHLIBEMITTER

Contains the emitter specification for the SharedLibrary builder. The manpage section "Builder Objects" contains general information on specifying emitters.

SHLIBNOVERSIONSYMLINKS

Instructs the SharedLibrary builder to not create symlinks for versioned shared libraries.

SHLIBPREFIX

The prefix used for shared library file names.

_SHLIBSONAME

A macro that automatically generates shared library's SONAME based on $TARGET, $SHLIBVERSION and $SHLIBSUFFIX. Used by SharedLibrary builder when the linker tool supports SONAME (e.g. gnulink).

SHLIBSUFFIX

The suffix used for shared library file names.

SHLIBVERSION

When this construction variable is defined, a versioned shared library is created by the SharedLibrary builder. This activates the $_SHLIBVERSIONFLAGS and thus modifies the $SHLINKCOM as required, adds the version number to the library name, and creates the symlinks that are needed. $SHLIBVERSION versions should exist as alphanumeric, decimal-delimited values as defined by the regular expression "\w+[\.\w+]*". Example $SHLIBVERSION values include '1', '1.2.3', and '1.2.gitaa412c8b'.

_SHLIBVERSIONFLAGS

This macro automatically introduces extra flags to $SHLINKCOM when building versioned SharedLibrary (that is when $SHLIBVERSION is set). _SHLIBVERSIONFLAGS usually adds $SHLIBVERSIONFLAGS and some extra dynamically generated options (such as -Wl,-soname=$_SHLIBSONAME. It is unused by "plain" (unversioned) shared libraries.

SHLIBVERSIONFLAGS

Extra flags added to $SHLINKCOM when building versioned SharedLibrary. These flags are only used when $SHLIBVERSION is set.

SHLINK

The linker for programs that use shared libraries. See also $LINK for linking static objects.

On POSIX systems (those using the link tool), you should normally not change this value as it defaults to a "smart" linker tool which selects a compiler driver matching the type of source files in use. So for example, if you set $SHCXX to a specific compiler name, and are compiling C++ sources, the smartlink function will automatically select the same compiler for linking.

SHLINKCOM

The command line used to link programs using shared libraries. See also $LINKCOM for linking static objects.

SHLINKCOMSTR

The string displayed when programs using shared libraries are linked. If this is not set, then $SHLINKCOM (the command line) is displayed. See also $LINKCOMSTR for linking static objects.

env = Environment(SHLINKCOMSTR = "Linking shared $TARGET")

SHLINKFLAGS

General user options passed to the linker for programs using shared libraries. Note that this variable should not contain -l (or similar) options for linking with the libraries listed in $LIBS, nor -L (or similar) include search path options that scons generates automatically from $LIBPATH. See $_LIBFLAGS above, for the variable that expands to library-link options, and $_LIBDIRFLAGS above, for the variable that expands to library search path options. See also $LINKFLAGS for linking static objects.

SHOBJPREFIX

The prefix used for shared object file names.

SHOBJSUFFIX

The suffix used for shared object file names.

SONAME

Variable used to hard-code SONAME for versioned shared library/loadable module.

env.SharedLibrary('test', 'test.c', SHLIBVERSION='0.1.2', SONAME='libtest.so.2')

The variable is used, for example, by gnulink linker tool.

SOURCE

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

SOURCE_URL

The URL (web address) of the location from which the project was retrieved. This is used to fill in the Source: field in the controlling information for Ipkg and RPM packages.

See the Package builder.

SOURCES

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

SOVERSION

This will construct the SONAME using on the base library name (test in the example below) and use specified SOVERSION to create SONAME.

env.SharedLibrary('test', 'test.c', SHLIBVERSION='0.1.2', SOVERSION='2')

The variable is used, for example, by gnulink linker tool.

In the example above SONAME would be libtest.so.2 which would be a symlink and point to libtest.so.0.1.2

SPAWN

A command interpreter function that will be called to execute command line strings. The function must accept five arguments:

def spawn(shell, escape, cmd, args, env):

shell is a string naming the shell program to use, escape is a function that can be called to escape shell special characters in the command line, cmd is the path to the command to be executed, args holds the arguments to the command and env is a dictionary of environment variables defining the execution environment in which the command should be executed.

STATIC_AND_SHARED_OBJECTS_ARE_THE_SAME

When this variable is true, static objects and shared objects are assumed to be the same; that is, SCons does not check for linking static objects into a shared library.

SUBST_DICT

The dictionary used by the Substfile or Textfile builders for substitution values. It can be anything acceptable to the dict() constructor, so in addition to a dictionary, lists of tuples are also acceptable.

SUBSTFILEPREFIX

The prefix used for Substfile file names, an empty string by default.

SUBSTFILESUFFIX

The suffix used for Substfile file names, an empty string by default.

SUMMARY

A short summary of what the project is about. This is used to fill in the Summary: field in the controlling information for Ipkg and RPM packages, and as the Description: field in MSI packages.

See the Package builder.

SWIG

The name of the SWIG compiler to use.

SWIGCFILESUFFIX

The suffix that will be used for intermediate C source files generated by SWIG. The default value is '_wrap$CFILESUFFIX' - that is, the concatenation of the string _wrap and the current C suffix $CFILESUFFIX. By default, this value is used whenever the -c++ option is not specified as part of the $SWIGFLAGS construction variable.

SWIGCOM

The command line used to call SWIG.

SWIGCOMSTR

The string displayed when calling SWIG. If this is not set, then $SWIGCOM (the command line) is displayed.

SWIGCXXFILESUFFIX

The suffix that will be used for intermediate C++ source files generated by SWIG. The default value is '_wrap$CXXFILESUFFIX' - that is, the concatenation of the string _wrap and the current C++ suffix $CXXFILESUFFIX. By default, this value is used whenever the -c++ option is specified as part of the $SWIGFLAGS construction variable.

SWIGDIRECTORSUFFIX

The suffix that will be used for intermediate C++ header files generated by SWIG. These are only generated for C++ code when the SWIG 'directors' feature is turned on. The default value is _wrap.h.

SWIGFLAGS

General options passed to SWIG. This is where you should set the target language (-python, -perl5, -tcl, etc.) and whatever other options you want to specify to SWIG, such as the -c++ to generate C++ code instead of C Code.

_SWIGINCFLAGS

An automatically-generated construction variable containing the SWIG command-line options for specifying directories to be searched for included files. The value of $_SWIGINCFLAGS is created by respectively prepending and appending $SWIGINCPREFIX and $SWIGINCSUFFIX to the beginning and end of each directory in $SWIGPATH.

SWIGINCPREFIX

The prefix used to specify an include directory on the SWIG command line. This will be prepended to the beginning of each directory in the $SWIGPATH construction variable when the $_SWIGINCFLAGS variable is automatically generated.

SWIGINCSUFFIX

The suffix used to specify an include directory on the SWIG command line. This will be appended to the end of each directory in the $SWIGPATH construction variable when the $_SWIGINCFLAGS variable is automatically generated.

SWIGOUTDIR

Specifies the output directory in which SWIG should place generated language-specific files. This will be used by SCons to identify the files that will be generated by the SWIG call, and translated into the swig -outdir option on the command line.

SWIGPATH

The list of directories that SWIG will search for included files. SCons' SWIG implicit dependency scanner will search these directories for include files. The default value is an empty list.

Don't explicitly put include directory arguments in $SWIGFLAGS the result will be non-portable and the directories will not be searched by the dependency scanner. Note: directory names in $SWIGPATH will be looked-up relative to the SConscript directory when they are used in a command. To force scons to lookup a directory relative to the root of the source tree, use a top-relative path (#):

env = Environment(SWIGPATH='#/include')

The directory lookup can also be forced using the Dir() function:

include = Dir('include')
env = Environment(SWIGPATH=include)

The directory list will be added to command lines through the automatically-generated $_SWIGINCFLAGS construction variable, which is constructed by respectively prepending and appending the values of the $SWIGINCPREFIX and $SWIGINCSUFFIX construction variables to the beginning and end of each directory in $SWIGPATH. Any command lines you define that need the SWIGPATH directory list should include $_SWIGINCFLAGS:

env = Environment(SWIGCOM="my_swig -o $TARGET $_SWIGINCFLAGS $SOURCES")

SWIGVERSION

The detected version string of the SWIG tool.

TAR

The tar archiver.

TARCOM

The command line used to call the tar archiver.

TARCOMSTR

The string displayed when archiving files using the tar archiver. If this is not set, then $TARCOM (the command line) is displayed.

env = Environment(TARCOMSTR = "Archiving $TARGET")

TARFLAGS

General options passed to the tar archiver.

TARGET

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

TARGET_ARCH

The name of the hardware architecture that objects created using this construction environment should target. Can be set when creating a construction environment by passing as a keyword argument in the Environment call.

On the win32 platform, if the Microsoft Visual C++ compiler is available, msvc tool setup is done using $HOST_ARCH and $TARGET_ARCH. If a value is not specified, will be set to the same value as $HOST_ARCH. Changing the value after the environment is initialized will not cause the tool to be reinitialized. Compiled objects will be in the target architecture if the compilation system supports generating for that target. The latest compiler which can fulfill the requirement will be selected, unless a different version is directed by the value of the $MSVC_VERSION construction variable.

On the win32/msvc combination, valid target arch values are x86, arm, i386 for 32-bit targets and amd64, arm64, x86_64 and ia64 (Itanium) for 64-bit targets. For example, if you want to compile 64-bit binaries, you would set TARGET_ARCH='x86_64' when creating the construction environment. Note that not all target architectures are supported for all Visual Studio / MSVC versions. Check the relevant Microsoft documentation.

$TARGET_ARCH is not currently used by other compilation tools, but the option is reserved to do so in future

TARGET_OS

The name of the operating system that objects created using this construction environment should target. Can be set when creating a construction environment by passing as a keyword argument in the Environment call;.

$TARGET_OS is not currently used by SCons but the option is reserved to do so in future

TARGETS

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

TARSUFFIX

The suffix used for tar file names.

TEMPFILE

Holds a callable object which will be invoked to transform long command lines (string or list) into an alternate form. Length limits on various operating systems may cause long command lines to fail when calling out to a shell to run the command. Most often affects linking, when there are many object files and/or libraries to be linked, but may also affect other compilation steps which have many arguments. $TEMPFILE is not called directly, but rather is typically embedded in another construction variable, to be expanded when used. Example:

env["TEMPFILE"] = TempFileMunge
env["LINKCOM"] = "${TEMPFILE('$LINK $TARGET $SOURCES', '$LINKCOMSTR')}"

The SCons default value for $TEMPFILE, TempFileMunge, performs command substitution on the passed command line, calculates whether modification is needed, then puts all but the first word (assumed to be the command name) of the resulting list into a temporary file (sometimes called a response file or command file), and returns a new command line consisting of the the command name and an appropriately formatted reference to the temporary file.

A replacement for the default tempfile object would need to do fundamentally the same thing, including taking into account the values of $MAXLINELENGTH, $TEMPFILEPREFIX, $TEMPFILESUFFIX, $TEMPFILEARGJOIN, $TEMPFILEDIR and $TEMPFILEARGESCFUNC. If a particular use case requires a different transformation than the default, it is recommended to copy the mechanism and define a new construction variable and rewrite the relevant *COM variable(s) to use it, to avoid possibly disrupting existing uses of $TEMPFILE.

TEMPFILEARGESCFUNC

The default argument escape function is SCons.Subst.quote_spaces. If you need to apply extra operations on a command argument (to fix Windows slashes, normalize paths, etc.) before writing to the temporary file, you can set the $TEMPFILEARGESCFUNC variable to a custom function. Such a function takes a single string argument and returns a new string with any modifications applied. Example:

import sys
import re
from SCons.Subst import quote_spaces

WINPATHSEP_RE = re.compile(r"\\([^\"'\\]|$)")

def tempfile_arg_esc_func(arg):
    arg = quote_spaces(arg)
    if sys.platform != "win32":
        return arg
    # GCC requires double Windows slashes, let's use UNIX separator
    return WINPATHSEP_RE.sub(r"/\1", arg)

env["TEMPFILEARGESCFUNC"] = tempfile_arg_esc_func

TEMPFILEARGJOIN

The string to use to join the arguments passed to $TEMPFILE when the command line exceeds the limit set by $MAXLINELENGTH. The default value is a space. However for MSVC, MSLINK the default is a line separator as defined by os.linesep. Note this value is used literally and not expanded by the subst logic.

TEMPFILEDIR

The directory to create the long-lines temporary file in. If unset, some suitable default should be chosen. The default tempfile object lets the Python tempfile module choose.

TEMPFILEPREFIX

The prefix for the name of the temporary file used to store command lines exceeding $MAXLINELENGTH. The prefix must include the compiler syntax to actually include and process the file. The default prefix is '@', which works for the Microsoft Visual C++ and GNU toolchains on Windows. Set this appropriately for other toolchains, for example '-@' for the diab compiler or '-via' for ARM toolchain.

TEMPFILESUFFIX

The suffix for the name of the temporary file used to store command lines exceeding $MAXLINELENGTH. The suffix should include the dot ('.') if one is needed as it will not be added automatically. The default is .lnk.

TEX

The TeX formatter and typesetter.

TEXCOM

The command line used to call the TeX formatter and typesetter.

TEXCOMSTR

The string displayed when calling the TeX formatter and typesetter. If this is not set, then $TEXCOM (the command line) is displayed.

env = Environment(TEXCOMSTR = "Building $TARGET from TeX input $SOURCES")

TEXFLAGS

General options passed to the TeX formatter and typesetter.

TEXINPUTS

List of directories that the LaTeX program will search for include directories. The LaTeX implicit dependency scanner will search these directories for \include and \import files.

TEXTFILEPREFIX

The prefix used for Textfile file names, an empty string by default.

TEXTFILESUFFIX

The suffix used for Textfile file names; .txt by default.

TOOLS

A list of the names of the Tool specification modules that were actually initialized in the current construction environment. This may be useful as a diagnostic aid to see if a tool did (or did not) run. The value is informative and is not guaranteed to be complete.

UNCHANGED_SOURCES

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

UNCHANGED_TARGETS

A reserved variable name that may not be set or used in a construction environment. (See the manpage section "Variable Substitution" for more information).

VENDOR

The person or organization who supply the packaged software. This is used to fill in the Vendor: field in the controlling information for RPM packages, and the Manufacturer: field in the controlling information for MSI packages.

See the Package builder.

VERSION

The version of the project, specified as a string.

See the Package builder.

VSWHERE

Specify the location of vswhere.exe.

The vswhere.exe executable is distributed with Microsoft Visual Studio and Build Tools since the 2017 edition, but is also available as a standalone installation. It allows queries to obtain detailed information about installations of 2017 and later editions. SCons makes use of this information to determine the state of compiler support for those editions.

Setting the $VSWHERE variable to the path to a specific vswhere.exe binary causes SCons to use that binary. If not set, SCons will search for one, looking in the following locations in order, using the first found ($VSWHERE is updated with the location):

%ProgramFiles(x86)%\Microsoft Visual Studio\Installer
%ProgramFiles%\Microsoft Visual Studio\Installer
%ChocolateyInstall%\bin
%LOCALAPPDATA%\Microsoft\WinGet\Links
%USERPROFILE%\scoop\shims
%SCOOP%\shims

Note
In order to take effect, $VSWHERE must be set before the initial Microsoft Visual C++ compiler discovery takes place. Discovery happens, at the latest, during the first call to the Environment function, unless a tools list is specified which excludes the entire Microsoft Visual C++ toolchain - that is, omits "defaults" and any specific tool module that refers to parts of the toolchain (msvc, mslink, masm, midl and msvs). In this case, detection is deferred until any one of those tool modules is invoked manually. The following two examples illustrate this:

# VSWHERE set as Environment is created
env = Environment(VSWHERE='c:/my/path/to/vswhere')

# Initialization deferred with empty tools, triggered manually
env = Environment(tools=[])
env['VSWHERE'] = r'c:/my/vswhere/install/location/vswhere.exe'
env.Tool('msvc')
env.Tool('mslink')
env.Tool('msvs')

WINDOWS_EMBED_MANIFEST

Set to True to embed the compiler-generated manifest (normally ${TARGET}.manifest) into all Windows executables and DLLs built with this environment, as a resource during their link step. This is done using $MT and $MTEXECOM and $MTSHLIBCOM. See also $WINDOWS_INSERT_MANIFEST.

WINDOWS_INSERT_DEF

If set to true, a library build of a Windows shared library (.dll file) will include a reference to the corresponding module-definition file at the same time, if a module-definition file is not already listed as a build target. The name of the module-definition file will be constructed from the base name of the library and the construction variables $WINDOWSDEFSUFFIX and $WINDOWSDEFPREFIX. The default is to not add a module-definition file. The module-definition file is not created by this directive, and must be supplied by the developer.

WINDOWS_INSERT_MANIFEST

If set to true, scons will add the manifest file generated by Microsoft Visual C++ 8.0 and later to the target list so SCons will be aware they were generated. In the case of an executable, the manifest file name is constructed using $WINDOWSPROGMANIFESTSUFFIX and $WINDOWSPROGMANIFESTPREFIX. In the case of a shared library, the manifest file name is constructed using $WINDOWSSHLIBMANIFESTSUFFIX and $WINDOWSSHLIBMANIFESTPREFIX. See also $WINDOWS_EMBED_MANIFEST.

WINDOWSDEFPREFIX

The prefix used for a Windows linker module-definition file name. Defaults to empty.

WINDOWSDEFSUFFIX

The suffix used for a Windows linker module-definition file name. Defaults to .def.

WINDOWSEXPPREFIX

The prefix used for Windows linker exports file names. Defaults to empty.

WINDOWSEXPSUFFIX

The suffix used for Windows linker exports file names. Defaults to .exp.

WINDOWSPROGMANIFESTPREFIX

The prefix used for executable program manifest files generated by Microsoft Visual C++. Defaults to empty.

WINDOWSPROGMANIFESTSUFFIX

The suffix used for executable program manifest files generated by Microsoft Visual C++. Defaults to .manifest.

WINDOWSSHLIBMANIFESTPREFIX

The prefix used for shared library manifest files generated by Microsoft Visual C++. Defaults to empty.

WINDOWSSHLIBMANIFESTSUFFIX

The suffix used for shared library manifest files generated by Microsoft Visual C++. Defaults to .manifest.

X_IPK_DEPENDS

This is used to fill in the Depends: field in the controlling information for Ipkg packages.

See the Package builder.

X_IPK_DESCRIPTION

This is used to fill in the Description: field in the controlling information for Ipkg packages. The default value is “$SUMMARY\n$DESCRIPTION”

X_IPK_MAINTAINER

This is used to fill in the Maintainer: field in the controlling information for Ipkg packages.

X_IPK_PRIORITY

This is used to fill in the Priority: field in the controlling information for Ipkg packages.

X_IPK_SECTION

This is used to fill in the Section: field in the controlling information for Ipkg packages.

X_MSI_LANGUAGE

This is used to fill in the Language: attribute in the controlling information for MSI packages.

See the Package builder.

X_MSI_LICENSE_TEXT

The text of the software license in RTF format. Carriage return characters will be replaced with the RTF equivalent \\par.

See the Package builder.

X_MSI_UPGRADE_CODE

TODO

X_RPM_AUTOREQPROV

This is used to fill in the AutoReqProv: field in the RPM .spec file.

See the Package builder.

X_RPM_BUILD

internal, but overridable

X_RPM_BUILDREQUIRES

This is used to fill in the BuildRequires: field in the RPM .spec file. Note this should only be used on a host managed by rpm as the dependencies will not be resolvable at build time otherwise.

X_RPM_BUILDROOT

internal, but overridable

X_RPM_CLEAN

internal, but overridable

X_RPM_CONFLICTS

This is used to fill in the Conflicts: field in the RPM .spec file.

X_RPM_DEFATTR

This value is used as the default attributes for the files in the RPM package. The default value is “(-,root,root)”.

X_RPM_DISTRIBUTION

This is used to fill in the Distribution: field in the RPM .spec file.

X_RPM_EPOCH

This is used to fill in the Epoch: field in the RPM .spec file.

X_RPM_EXCLUDEARCH

This is used to fill in the ExcludeArch: field in the RPM .spec file.

X_RPM_EXLUSIVEARCH

This is used to fill in the ExclusiveArch: field in the RPM .spec file.

X_RPM_EXTRADEFS

A list used to supply extra definitions or flags to be added to the RPM .spec file. Each item is added as-is with a carriage return appended. This is useful if some specific RPM feature not otherwise anticipated by SCons needs to be turned on or off. Note if this variable is omitted, SCons will by default supply the value '%global debug_package %{nil}' to disable debug package generation. To enable debug package generation, include this variable set either to None, or to a custom list that does not include the default line.

New in version 3.1.

env.Package(
    NAME="foo",
    ...
    X_RPM_EXTRADEFS=[
        "%define _unpackaged_files_terminate_build 0"
        "%define _missing_doc_files_terminate_build 0"
    ],
    ...
)

X_RPM_GROUP

This is used to fill in the Group: field in the RPM .spec file.

X_RPM_GROUP_lang

This is used to fill in the Group(lang): field in the RPM .spec file. Note that lang is not literal and should be replaced by the appropriate language code.

X_RPM_ICON

This is used to fill in the Icon: field in the RPM .spec file.

X_RPM_INSTALL

internal, but overridable

X_RPM_PACKAGER

This is used to fill in the Packager: field in the RPM .spec file.

X_RPM_POSTINSTALL

This is used to fill in the %post: section in the RPM .spec file.

X_RPM_POSTUNINSTALL

This is used to fill in the %postun: section in the RPM .spec file.

X_RPM_PREFIX

This is used to fill in the Prefix: field in the RPM .spec file.

X_RPM_PREINSTALL

This is used to fill in the %pre: section in the RPM .spec file.

X_RPM_PREP

internal, but overridable

X_RPM_PREUNINSTALL

This is used to fill in the %preun: section in the RPM .spec file.

X_RPM_PROVIDES

This is used to fill in the Provides: field in the RPM .spec file.

X_RPM_REQUIRES

This is used to fill in the Requires: field in the RPM .spec file.

X_RPM_SERIAL

This is used to fill in the Serial: field in the RPM .spec file.

X_RPM_URL

This is used to fill in the Url: field in the RPM .spec file.

XGETTEXT

Path to xgettext(1) program (found via Detect()). See xgettext tool and POTUpdate builder.

XGETTEXTCOM

Complete xgettext command line. See xgettext tool and POTUpdate builder.

XGETTEXTCOMSTR

A string that is shown when xgettext(1) command is invoked (default: '', which means "print $XGETTEXTCOM"). See xgettext tool and POTUpdate builder.

_XGETTEXTDOMAIN

Internal "macro". Generates xgettext domain name form source and target (default: '${TARGET.filebase}').

XGETTEXTFLAGS

Additional flags to xgettext(1). See xgettext tool and POTUpdate builder.

XGETTEXTFROM

Name of file containing list of xgettext(1)'s source files. Autotools' users know this as POTFILES.in so they will in most cases set XGETTEXTFROM="POTFILES.in" here. The $XGETTEXTFROM files have same syntax and semantics as the well known GNU POTFILES.in. See xgettext tool and POTUpdate builder.

_XGETTEXTFROMFLAGS

Internal "macro". Generates list of -D<dir> flags from the $XGETTEXTPATH list.

XGETTEXTFROMPREFIX

This flag is used to add single $XGETTEXTFROM file to xgettext(1)'s command line (default: '-f').

XGETTEXTFROMSUFFIX

(default: '')

XGETTEXTPATH

List of directories, there xgettext(1) will look for source files (default: []).

Note
This variable works only together with $XGETTEXTFROM

See also xgettext tool and POTUpdate builder.

_XGETTEXTPATHFLAGS

Internal "macro". Generates list of -f<file> flags from $XGETTEXTFROM.

XGETTEXTPATHPREFIX

This flag is used to add single search path to xgettext(1)'s command line (default: '-D').

XGETTEXTPATHSUFFIX

(default: '')

YACC

The parser generator.

YACC_GRAPH_FILE

If supplied, write a graph of the automaton to a file with the name taken from this variable. Will be emitted as a --graph= command-line option. Use this in preference to including --graph= in $YACCFLAGS directly.

New in version 4.4.0.

YACC_GRAPH_FILE_SUFFIX

Previously specified by $YACCVCGFILESUFFIX.

The suffix of the file containing a graph of the grammar automaton when the -g option (or --graph= without an option-argument) is used in $YACCFLAGS. Note that setting this variable informs SCons how to construct the graph filename for tracking purposes, it does not affect the actual generated filename. Various yacc tools have emitted various formats at different times. Set this to match what your parser generator produces.

New in version 4.6.0.

YACC_HEADER_FILE

If supplied, generate a header file with the name taken from this variable. Will be emitted as a --header= command-line option. Use this in preference to including --header= in $YACCFLAGS directly.

New in version 4.4.0.

YACCCOM

The command line used to call the parser generator to generate a source file.

YACCCOMSTR

The string displayed when generating a source file using the parser generator. If this is not set, then $YACCCOM (the command line) is displayed.

env = Environment(YACCCOMSTR="Yacc'ing $TARGET from $SOURCES")

YACCFLAGS

General options passed to the parser generator. In addition to passing the value on during invocation, the yacc tool also examines this construction variable for options which cause additional output files to be generated, and adds those to the target list.

If the -d option is present in $YACCFLAGS scons assumes that the call will also create a header file with the suffix defined by $YACCHFILESUFFIX if the yacc source file ends in a .y suffix, or a file with the suffix defined by $YACCHXXFILESUFFIX if the yacc source file ends in a .yy suffix. The header will have the same base name as the requested target. This is only correct if the executable is bison (or win_bison). If using Berkeley yacc (byacc), y.tab.h is always written - avoid the -d in this case and use $YACC_HEADER_FILE instead.

If a -g option is present, scons assumes that the call will also create a graph file with the suffix defined by $YACCVCGFILESUFFIX.

If a -v option is present, scons assumes that the call will also create an output debug file with the suffix .output.

Also recognized are GNU bison options --header (and its deprecated synonym --defines), which is similar to -d but gives the option to explicitly name the output header file through an option argument; and --graph, which is similar to -g but gives the option to explicitly name the output graph file through an option argument. The file suffixes described for -d and -g above are not applied if these are used in the option=argument form.

Note that files specified by --header= and --graph= may not be properly handled by SCons in all situations, and using those in $YACCFLAGS should be considered legacy support only. Consider using $YACC_HEADER_FILE and $YACC_GRAPH_FILE instead if the files need to be explicitly named (new in version 4.4.0).

YACCHFILESUFFIX

The suffix of the C header file generated by the parser generator when the -d option (or --header without an option-argument) is used in $YACCFLAGS. Note that setting this variable informs SCons how to construct the header filename for tracking purposes, it does not affect the actual generated filename. Set this to match what your parser generator produces. The default value is .h.

YACCHXXFILESUFFIX

The suffix of the C++ header file generated by the parser generator when the -d option (or --header without an option-argument) is used in $YACCFLAGS. Note that setting this variable informs SCons how to construct the header filename for tracking purposes, it does not affect the actual generated filename. Set this to match what your parser generator produces. The default value is .hpp.

YACCVCGFILESUFFIX

Obsoleted. Use $YACC_GRAPH_FILE_SUFFIX instead. The value is used only if $YACC_GRAPH_FILE_SUFFIX is not set. The default value is .gv.

Changed in version 4.6.0: deprecated. The default value changed from .vcg (bison stopped generating .vcg output with version 2.4, in 2006).

ZIP

The zip compression and file packaging utility.

ZIP_OVERRIDE_TIMESTAMP

An optional timestamp which overrides the last modification time of the file when stored inside the Zip archive. This is a tuple of six values: Year (>= 1980) Month (one-based) Day of month (one-based) Hours (zero-based) Minutes (zero-based) Seconds (zero-based)

ZIPCOM

The command line used to call the zip utility, or the internal Python function used to create a zip archive.

ZIPCOMPRESSION

The compression flag from the Python zipfile module used by the internal Python function to control whether the zip archive is compressed or not. The default value is zipfile.ZIP_DEFLATED, which creates a compressed zip archive. This value has no effect if the zipfile module is unavailable.

ZIPCOMSTR

The string displayed when archiving files using the zip utility. If this is not set, then $ZIPCOM (the command line or internal Python function) is displayed.

env = Environment(ZIPCOMSTR = "Zipping $TARGET")

ZIPFLAGS

General options passed to the zip utility.

ZIPROOT

An optional zip root directory (default empty). The filenames stored in the zip file will be relative to this directory, if given. Otherwise, the filenames are relative to the current directory of the command. For instance:

env = Environment()
env.Zip('foo.zip', 'subdir1/subdir2/file1', ZIPROOT='subdir1')

will produce a zip file foo.zip containing a file with the name subdir2/file1 rather than subdir1/subdir2/file1.

ZIPSUFFIX

The suffix used for zip file names.