mkbundle man page

mkbundle, mkbundle2 — Creates a bundled executable.


mkbundle [options] assembly1 [assembly2 ...]


mkbundle generates an executable program that will contain static copies of the assemblies listed on the command line.  By default only the assemblies specified in the command line will be included in the bundle.  To automatically include all of the dependencies referenced, use the "--deps" command line option.

There are two modes of operation, one uses an existing Mono binary or a server-hosted list of binaries and is enabled when you use either the --cross, --sdk or the --runtime command line options.  

An older mechanism creates a small C stub that links against the libmono library to produce a self-contained executable and requires a C compiler.   It is described in the "Old Embedding" section below.

For example, to create a bundle for hello world, use the following command:

	$ mkbundle -o hello --simple hello.exe

You can configure options to be passed to the Mono runtime directly into your executable, for this, use the --options flag.  For example, the following disables inlining, by passing the "-O=-inline" command line option to the embedded executable:

	$ mkbundle -o hello --options -O=-inline --simple hello.exe

The simple version allows for cross-compiling, this requires a Mono
runtime to be installed in the ~/.mono/targets/TARGET/mono to be
available.   You can use the "--local-targets" to list all available
targets, and the "--cross" argument to specify the target, like this:

	$ mkbundle --local-targets	
	Available targets:
		default	- Current System Mono
	$ mkbundle --cross 4.4.0-debian-8-powerpc hello.exe -o hello-debian

The above will bundle your native library into hello-debian for a Debian 8 system running on a PowerPC machine.

We provide pre-packages binaries for Mono for various architectures, which allow you to cross compile, use the --list-targets to get a list of all targets supported, and use the --fetch-target flag to retrieve a target that you do not have installed, like this:

	$ mkbundle --list-targets
	Cross-compilation targets available:

	$ mkbundle --fetch-target 4.4.2-macos-10.7-i386

And then you can produce a binary that will run on 32-bit Mono on MacOS:

	$ mkbundle --cross 4.4.2-macos-10.7-i386 hello.exe -o hello-macos

Downloaded targets are stored ~/.mono/targets directory.


--config FILE

Specifies that a machine.config file must be bundled as well. Typically this is $prefix/etc/mono/1.0/machine.config or $prefix/etc/mono/2.0/machine.config depending on the profile that you are using (1.0 or 2.0)

--config-dir DIR

When passed, DIR will be set for the MONO_CFG_DIR environment variable

--cross target

Use this to request mkbundle generate a cross-compiled binary.  It Creates a bundle for the specified target platform.  The target must be a directory in ~/.mono/targets/ that contains an SDK installation as produced by the mono-package-runtime tool.  You can get a list of the precompiled versions of the runtime using --list-targets and you can fetch a specific target using the --fetch-target command line option.

This flag is mutually exclusive with --sdk which is used to specify an absolute path to resolve the Mono runtime from and the --runtime option which is used to manually construct the cross-platform package.


This option will bundle all of the referenced assemblies for the assemblies listed on the command line option.  This is useful to distribute a self-contained image.


Use this to hardcode an environment variable at runtime for KEY to be mapped to VALUE.   This is useful in scenarios where you want to enable certain Mono runtime configuration options that are controlled by environment variables.

--fetch-target target

Downloads a precompiled runtime for the specified target from the Mono distribution site.

--i18n encoding

Specified which encoding tables to ship with the executable.   By default, Mono ships the supporting I18N.dll assembly and the I18N.West.dll assembly.   If your application will use the System.Text.Encoding.GetEncoding with encodings other than the West encodings, you should specify them here.

You can use the none parameter to request that no implicit encodings should be bundled, including the supporting I18N.dll, use this option if you have ran a linker on your own.

You can use the all flag to bundle all available encodings.

Or you can use a comma delimited list of the workds CJK, MidWest, Other, Rare and West to specificy which encoding assemblies to distribute.

-L path

Adds the `path' do the search list for assemblies.  The rules are the same as for the compiler -lib: or -L flags.

--library [LIB,]PATH

Embeds the dynamic library file pointed to by `PATH' and optionally give it the name `LIB' into the bundled executable.   This is used to ship native library dependencies that are unpacked at startup and loaded from the runtime.


Lists all of the available local cross compilation targets available as precompiled binaries on the Mono distribution server.


Lists all of the available local cross compilation targets.

--machine-config FILE

Uses the given FILE as the machine.config file for the generated application.  


This is the default: mkbundle will only include the assemblies that were specified on the command line to reduce the size of the resulting image created.

-o filename

Places the output on `out'.  If the flag -c is specified, this is the C host program.  If not, this contains the resulting executable.

--options OPTS

Since the resulting executable will be treated as a standalone program, you can use this option to pass configuration options to the Mono runtime and bake those into the resulting executable.  These options are specified as OPTS.

You can use the above to configure options that you would typically pass on the command line to Mono, before the main program is executed.  

Additionally, users of your binary can still configure their own options by setting the MONO_ENV_OPTIONS environment variable.

--sdk SDK_PATH

Use this flag to specify a path from which mkbundle will resolve the Mono SDK from.   The SDK path should be the prefix path that you used to configure a Mono installation.   And would typically contain files lik SDK_PATH/bin/mono , SDK_PATH/lib/mono/4.5 and so on.

When this flag is specified, mkbundle will resolve the runtime, the framework libraries, unmanaged resources and configuration files from the files located in this directory.

This flag is mutually exlusive with --cross

--target-server SERVER

By default the mkbundle tool will download from a Mono server the target runtimes, you can specify a different server to provide cross-compiled runtimes.

Old Embedding

The old embedding system compiles a small C stub that embeds the C code and compiles the resulting executable using the system compiler.   This requires both a working C compiler installation and only works to bundle binaries for the current host.

The feature is still available, but we recommend the simpler, faster and more convenient new mode.

For example, to create a bundle for hello world, use the following command:

	$ mkbundle -o hello hello.exe

The above will pull hello.exe into a native program called "hello".  Notice that the produced image still contains the CIL image and no precompilation is done.

In addition, it is possible to control whether mkbundle should compile the resulting executable or not with the -c option.  This is useful if you want to link additional libraries or control the generated output in more detail. For example, this could be used to link some libraries statically:

	$ mkbundle -c -o host.c -oo bundles.o --deps hello.exe

	$ cc host.c bundles.o /usr/lib/libmono.a -lc -lrt

You may also use mkbundle to generate a bundle you can use when embedding the Mono runtime in a native application.  In that case, use both the -c and --nomain options.  The resulting host.c file will not have a main() function.  Call mono_mkbundle_init() before initializing the JIT in your code so that the bundled assemblies are available to the embedded runtime.

Old Embedding Options

These options can only be used instead of using the --cross, --runtime or --simple options.


Produce the stub file, do not compile the resulting stub.

-oo filename

Specifies the name to be used for the helper object file that contains the bundle.


By default mkbundle will delete the temporary files that it uses to produce the bundle.  This option keeps the file around.


With the -c option, generate the host stub without a main() function.


By default mkbundle dynamically links to mono and glib.  This option causes it to statically link instead.


Compresses the assemblies before embedding. This results in smaller executable files, but increases startup time and requires zlib to be installed on the target system.


If you are using the old embedding on Windows systems, it it necessary to have Unix-like toolchain to be installed for mkbundle to work.  You can use cygwin's and install gcc, gcc-mingw and as packages.

Environment Variables


Assembler command. The default is "as".


C compiler command. The default is "cc" under Linux and "gcc" under Windows.


Options to be passed to the bundled Mono runtime, separated by spaces. See the mono(1) manual page or run mono --help.


This program will load referenced assemblies from the Mono assembly cache.

Targets are loaded from ~/.mono/targets/TARGETNAME/mono


The option "--static" is not supported under Windows when using the old embedding. Moreover, a full cygwin environment containing at least "gcc" and "as" is required for the build process. The generated executable does not depend on cygwin.

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See Also


Referenced By

mono-cil-strip(1), monolinker(1).