whereis - locate the binary, source, and manual page files for a command
whereis [options] [-BMS directory... -f] name...
whereis locates the binary, source and manual files for the specified command names. The supplied names are first stripped of leading pathname components and any (single) trailing extension of the form .ext (for example: .c) Prefixes of s. resulting from use of source code control are also dealt with. whereis then attempts to locate the desired program in the standard Linux places, and in the places specified by $PATH and $MANPATH. The search restrictions (options -b, -m and -s) are cumulative and apply to the subsequent name patterns on the command line. Any new search restriction resets the search mask. For example, whereis -bm ls tr -m gcc searches for "ls" and "tr" binaries and man pages, and for "gcc" man pages only. The options -B, -M and -S reset search paths for the subsequent name patterns. For example, whereis -m ls -M /usr/share/man/man1 -f cal searches for "ls" man pages in all default paths, but for "cal" in the /usr/share/man/man1 directory only.
-b Search for binaries. -m Search for manuals. -s Search for sources. -u Only show the command names that have unusual entries. A command is said to be unusual if it does not have just one entry of each explicitly requested type. Thus 'whereis -m -u *' asks for those files in the current directory which have no documentation file, or more than one. -B list Limit the places where whereis searches for binaries, by a whitespace-separated list of directories. -M list Limit the places where whereis searches for manuals and documentation in Info format, by a whitespace-separated list of directories. -S list Limit the places where whereis searches for sources, by a whitespace-separated list of directories. -f Terminates the directory list and signals the start of filenames. It must be used when any of the -B, -M, or -S options is used. -l Output the list of effective lookup paths that whereis is using. When none of -B, -M, or -S is specified, the option will output the hard-coded paths that the command was able to find on the system.
To find all files in /usr/bin which are not documented in /usr/ man/man1 or have no source in /usr/src: cd /usr/bin whereis -u -ms -M /usr/man/man1 -S /usr/src -f *
By default whereis tries to find files from hard-coded paths, which are defined with glob patterns. The command attempts to use the contents of $PATH and $MANPATH environment variables as default search path. The easiest way to know what paths are in use is to add the -l listing option. Effects of the -B, -M, and -S are displayed with -l.
WHEREIS_DEBUG=all enables debug output.
The whereis command is part of the util-linux package and is available from Linux Kernel Archive ftp://ftp.kernel.org/pub /linux/utils/util-linux/.
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