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bfs - Man Page

breadth-first search for your files

Synopsis

bfs [flags...] [paths...] [expression...]

flags (-H/-L/-P etc.), paths, and expressions may be freely mixed in any order.

Description

bfs is a breadth-first version of the UNIX find(1) command.

bfs supports almost every feature from every major find(1) implementation, so your existing command lines should work as-is. It also adds some features of its own, such as a more forgiving command line parser and some additional options.

Each path specified on the command line is treated as a starting path to search through. If no paths are specified, the current directory (.) is searched by default.

Like find(1), bfs interprets its arguments as a short-circuiting Boolean expression. For example,

    bfs \( -name '*.txt' -or -lname '*.txt' \) -and -print

will print the all the paths that are either .txt files or symbolic links to .txt files. -and is implied between two consecutive expressions, so this is equivalent:

    bfs \( -name '*.txt' -or -lname '*.txt' \) -print

Finally, -print is implied if no actions are specified, so this too is equivalent:

    bfs -name '*.txt' -or -lname '*.txt'

Most options that take a numeric argument N will also accept -N or +N. -N means "less than N," and +N means "greater than N."

Flags

-H

Follow symbolic links on the command line, but not while searching.

-L

Follow all symbolic links.

-P

Never follow symbolic links (the default).

-E

Use extended regular expressions (same as -regextype posix-extended).

-X

Filter out files with non-xargs(1)-safe names.

-d

Search in post-order (same as -depth).

-s

Visit directory entries in sorted order. The sorting takes place within each directory separately, which makes it different from bfs ... | sort, but still provides a deterministic ordering.

-x

Don't descend into other mount points (same as -xdev).

-f PATH

Treat PATH as a path to search (useful if it begins with a dash).

-D FLAG

Turn on a debugging flag (see -D help).

-ON

Enable optimization level N (default: 3).

-O0

Disable all optimizations.

-O1

Basic logical simplifications.

-O2

All -O1 optimizations, plus dead code elimination and data flow analysis.

-O3

All -O2 optimizations, plus re-order expressions to reduce expected cost.

-O4/-Ofast

All optimizations, including aggressive optimizations that may alter the observed behavior in corner cases.

-S bfs|dfs|ids|eds

Choose the search strategy.

bfs

Breadth-first search (the default).

dfs

Depth-first search. Uses less memory than breadth-first search, but is typically slower to return relevant results.

ids

Iterative deepening search. Performs repeated depth-first searches with increasing depth limits. This gives results in the same order as breadth-first search, but with the reduced memory consumption of depth-first search. Tends to be very slow in practice, so use it only if you absolutely need breadth-first ordering, but -S bfs consumes too much memory.

eds

Exponential deepening search. A compromise between breadth- and depth-first search, which searches exponentially increasing depth ranges (e.g. 0-1, 1-2, 2-4, 4-8, etc.). Provides many of the benefits of breadth-first search with depth-first's reduced memory consumption. Typically far faster than -S ids.

-jN

Search with N threads in parallel (default: number of CPUs, up to 8).

Operators

( expression )

Parentheses are used for grouping expressions together. You'll probably have to write \( expression \) to avoid the parentheses being interpreted by the shell.

! expression
-not expression

The "not" operator: returns the negation of the truth value of the expression. You may have to write \! expression to avoid ! being interpreted by the shell.

expression expression
expression -a expression
expression -and expression

Short-circuiting "and" operator: if the left-hand expression is true, returns the right-hand expression; otherwise, returns false.

expression -o expression
expression -or expression

Short-circuiting "or" operator: if the left-hand expression is false, returns the right-hand expression; otherwise, returns true.

expression , expression

The "comma" operator: evaluates the left-hand expression but discards the result, returning the right-hand expression.

Special Forms

-exclude expression

Exclude all paths matching the expression from the search. This is more powerful than -prune, because it applies even when the expression wouldn't otherwise be evaluated, due to -depth or -mindepth for example. Exclusions are always applied before other expressions, so it may be least confusing to put them first on the command line.

-help
--help

Print usage information, and exit immediately (without parsing the rest of the command line or processing any files).

-version
--version

Print version information, and exit immediately.

Options

-color
-nocolor

Turn colors on or off (default: -color if outputting to a terminal, -nocolor otherwise).

-daystart

Measure time relative to the start of today.

-depth

Search in post-order (descendents first).

-follow

Follow all symbolic links (same as -L).

-files0-from FILE

Treat the NUL ('\0')-separated paths in FILE as starting points for the search. Pass -files0-from - to read the paths from standard input.

-ignore_readdir_race
-noignore_readdir_race

Whether to report an error if bfs detects that the file tree is modified during the search (default: -noignore_readdir_race).

-maxdepth N
-mindepth N

Ignore files deeper/shallower than N.

-mount

Don't descend into other mount points (same as -xdev for now, but will skip mount points entirely in the future).

-nohidden

Exclude hidden files and directories.

-noleaf

Ignored; for compatibility with GNU find.

-regextype TYPE

Use TYPE-flavored regular expressions. The possible types are

posix-basic

POSIX basic regular expressions (the default).

posix-extended

POSIX extended resular expressions.

ed

Like ed(1) (same as posix-basic).

emacs

Like emacs(1).

grep

Like grep(1).

sed

Like sed(1) (same as posix-basic).

See regex(7) for a description of regular expression syntax.

-status

Display a status bar while searching.

-unique

Skip any files that have already been seen. Particularly useful along with -L.

-warn
-nowarn

Turn on or off warnings about the command line.

-xdev

Don't descend into other mount points.

Tests

-acl

Find files with a non-trivial Access Control List (acl(5)).

-amin [-+]N
-Bmin [-+]N
-cmin [-+]N
-mmin [-+]N

Find files accessed/Birthed/changed/modified N minutes ago.

-anewer FILE
-Bnewer FILE
-cnewer FILE
-mnewer FILE

Find files accessed/Birthed/changed/modified more recently than FILE was modified.

-asince TIME
-Bsince TIME
-csince TIME
-msince TIME

Find files accessed/Birthed/changed/modified more recently than the ISO 8601-style timestamp TIME. See -newerXY for examples of the timestamp format.

-atime [-+]N
-Btime [-+]N
-ctime [-+]N
-mtime [-+]N

Find files accessed/Birthed/changed/modified N days ago.

-capable

Find files with POSIX.1e capabilities(7) set.

-context GLOB

Find files whose SELinux context matches the GLOB.

-depth [-+]N

Find files with depth N.

-empty

Find empty files/directories.

-executable
-readable
-writable

Find files the current user can execute/read/write.

-false
-true

Always false/true.

-flags [-+]FLAGS

Find files with matching inode Flags.

-fstype TYPE

Find files on file systems with the given TYPE.

-gid [-+]N
-uid [-+]N

Find files owned by group/user ID N.

-group NAME
-user NAME

Find files owned by the group/user NAME.

-hidden

Find hidden files (those beginning with .).

-ilname GLOB
-iname GLOB
-ipath GLOB
-iregex REGEX
-iwholename GLOB

Case-insensitive versions of -lname/-name/-path/-regex/-wholename.

-inum [-+]N

Find files with inode number N.

-links [-+]N

Find files with N hard links.

-lname GLOB

Find symbolic links whose target matches the GLOB.

-name GLOB

Find files whose name matches the GLOB.

-newer FILE

Find files newer than FILE.

-newerXY REFERENCE

Find files whose X time is newer than the Y time of REFERENCE. X and Y can be any of [aBcm] (access/Birth/change/modification). Y may also be t to parse REFERENCE as an ISO 8601-style timestamp.  For example:

·  1991-12-14
·  1991-12-14T03:00
·  1991-12-14T03:00-07:00
· '1991-12-14 10:00Z'
-nogroup
-nouser

Find files owned by nonexistent groups/users.

-path GLOB
-wholename GLOB

Find files whose entire path matches the GLOB.

-perm [-+/]MODE

Find files with a matching mode.

-regex REGEX

Find files whose entire path matches the regular expression REGEX.

-samefile FILE

Find hard links to FILE.

-since TIME

Find files modified since the ISO 8601-style timestamp TIME. See -newerXY for examples of the timestamp format.

-size [-+]N[cwbkMGTP]

Find files with the given size. The unit can be one of

· chars  (1 byte)
· words  (2 bytes)
· blocks (512 bytes, the default)
· kiB    (1024 bytes)
· MiB    (1024 kiB)
· GiB    (1024 MiB)
· TiB    (1024 GiB)
· PiB    (1024 TiB)
-sparse

Find files that occupy fewer disk blocks than expected.

-type [bcdlpfswD]

Find files of the given type. The possible types are

· block device
· character device
· directory
· link (symbolic)
· pipe
· file (regular)
· socket
· whiteout
· Door

Multiple types can be given at once, separated by commas. For example, -type d,f matches both directories and regular files.

-used [-+]N

Find files last accessed N days after they were changed.

-xattr

Find files with extended attributes (xattr(7)).

-xattrname NAME

Find files with the extended attribute NAME.

-xtype [bcdlpfswD]

Find files of the given type, following links when -type would not, and vice versa.

Actions

-delete
-rm

Delete any found files (implies -depth).

-exec command ... {} ;

Execute a command.

-exec command ... {} +

Execute a command with multiple files at once.

-ok command ... {} ;

Prompt the user whether to execute a command.

-execdir command ... {} ;
-execdir command ... {} +
-okdir command ... {} ;

Like -exec/-ok, but run the command in the same directory as the found file(s).

-exit [STATUS]

Exit immediately with the given status (0 if unspecified).

-fls FILE
-fprint FILE
-fprint0 FILE
-fprintf FILE FORMAT

Like -ls/-print/-print0/-printf, but write to FILE instead of standard output.

-limit N

Quit once this action is evaluated N times.

-ls

List files like ls -dils.

-print

Print the path to the found file.

-print0

Like -print, but use the null character ('\0') as a separator rather than newlines. Useful in conjunction with xargs -0.

-printf FORMAT

Print according to a format string (see find(1)). These additional format directives are supported:

%w

The file's birth time, in the same format as %a/%c/%t.

%Wk

Field k of the file's birth time, in the same format as %Ak/%Ck/%Tk.

-printx

Like -print, but escape whitespace and quotation characters, to make the output safe for xargs(1). Consider using -print0 and xargs -0 instead.

-prune

Don't descend into this directory. This has no effect if -depth is enabled (either explicitly, or implicitly by -delete). Use -exclude instead in that case.

-quit

Quit immediately.

Environment

Certain environment variables affect the behavior of bfs.

LANG
LC_*

Specifies the locale(7) in use for various things. bfs is not (yet) translated to any languages except English, but the locale will still affect the format of printed values. Yes/no prompts (e.g. from -ok) will also be interpreted according to the current locale.

LS_COLORS
BFS_COLORS

Controls the colors used when displaying file paths if -color is enabled. bfs interprets LS_COLORS the same way GNU ls(1) does (see dir_colors(5)). BFS_COLORS can be used to customize bfs without affecting other commands.

NO_COLOR

Causes bfs to default to -nocolor if it is set (see https://no-color.org/).

PAGER

Specifies the pager used for -help output. Defaults to less(1), if found on the current PATH, otherwise more(1).

PATH

Used to resolve executables for -exec[dir] and -ok[dir].

POSIXLY_CORRECT

Makes bfs conform more strictly to the POSIX.1-2017 specification for find(1). Currently this has two effects:

  • Disables warnings by default, because POSIX prohibits writing to standard error (except for the -ok prompt), unless the command also fails with a non-zero exit status.
  • Makes -ls and -fls use 512-byte blocks instead of 1024-byte blocks. (POSIX does not specify these actions, but BSD find(1) implementations use 512-byte blocks, while GNU find(1) uses 1024-byte blocks by default.)

It does not disable bfs's various extensions to the base POSIX functionality. POSIXLY_CORRECT has the same effects on GNU find(1).

Examples

bfs

With no arguments, bfs prints all files under the current directory in breadth-first order.

bfs -name '*.txt'

Prints all the .txt files under the current directory. *.txt is quoted to ensure the glob is processed by bfs rather than the shell.

bfs -name access_log -L /var

Finds all files named access_log under /var, following symbolic links. bfs allows flags and paths to appear anywhere on the command line.

bfs ~ -not -user $USER

Prints all files in your home directory not owned by you.

bfs -xtype l

Finds broken symbolic links.

bfs -name config -exclude -name .git

Finds all files named config, skipping every .git directory.

bfs -type f -executable -exec strip {} +

Runs strip(1) on all executable files it finds, passing it multiple files at a time.

Bugs

https://github.com/tavianator/bfs/issues

Author

Tavian Barnes <tavianator@tavianator.com>

https://tavianator.com/projects/bfs.html

See Also

find(1), locate(1), xargs(1)