Locate the binary, source, and manual page files for specified commands/files. The supplied filenames 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. where then attempts to locate the desired program in a list of standard Linux directories (e.g., /bin, /etc, /usr/bin, /usr/local/bin/, etc.).

Options
-b
Search only for binaries.

-f
Terminate the last directory list and signal the start of filenames; required when any of the -B, -M, or -S options are used.

-m
Search only for manual sections.

-s
Search only for sources.

-u
Search for unusual entries, that is, files that do not have one entry of each requested type. Thus, the command whereis -m -u * asks for those files in the current directory that have no documentation.

-B directories
Change or otherwise limit the directories to search for binaries.

-M directory
Change or otherwise limit the directories to search for manual sections.

-S directory
Change or otherwise limit the directories to search for sources.

Example
Find all files in /usr/bin that are not documented in /usr/man/man1 but that have source in /usr/src:

% cd /usr/bin
% where -u -M /usr/man/man1 -S /usr/src -f *