Manual: whatis

WHATIS(1) Manual pager utils WHATIS(1)

NAME
whatis - display one-line manual page descriptions

SYNOPSIS
whatis [-dlv?V] [-r|-w] [-s list] [-m system[,...]] [-M path] [-L locale] [-C file] name ...

DESCRIPTION
Each manual page has a short description available within it. whatis searches the manual page names and displays the
manual page descriptions of any name matched.

name may contain wildcards (-w) or be a regular expression (-r). Using these options, it may be necessary to quote
the name or escape (\) the special characters to stop the shell from interpreting them.

index databases are used during the search, and are updated by the mandb program. Depending on your installation,
this may be run by a periodic cron job, or may need to be run manually after new manual pages have been installed.
To produce an old style text whatis database from the relative index database, issue the command:

whatis -M manpath -w '*' | sort > manpath/whatis

where manpath is a manual page hierarchy such as /usr/man.

OPTIONS
-d, --debug
Print debugging information.

-v, --verbose
Print verbose warning messages.

-r, --regex
Interpret each name as a regular expression. If a name matches any part of a page name, a match will be made.
This option causes whatis to be somewhat slower due to the nature of database searches.

-w, --wildcard
Interpret each name as a pattern containing shell style wildcards. For a match to be made, an expanded name
must match the entire page name. This option causes whatis to be somewhat slower due to the nature of data‐
base searches.

-l, --long
Do not trim output to the terminal width. Normally, output will be truncated to the terminal width to avoid
ugly results from poorly-written NAME sections.

-s list, --sections=list, --section=list
Search only the given manual sections. list is a colon- or comma-separated list of sections. If an entry in
list is a simple section, for example "3", then the displayed list of descriptions will include pages in sec‐
tions "3", "3perl", "3x", and so on; while if an entry in list has an extension, for example "3perl", then the
list will only include pages in that exact part of the manual section.

-m system[,...], --systems=system[,...]
If this system has access to other operating systems' manual page names, they can be accessed using this op‐
tion. To search NewOS's manual page names, use the option -m NewOS.

The system specified can be a combination of comma delimited operating system names. To include a search of
the native operating system's manual page names, include the system name man in the argument string. This op‐
tion will override the $SYSTEM environment variable.

-M path, --manpath=path
Specify an alternate set of colon-delimited manual page hierarchies to search. By default, whatis uses the
$MANPATH environment variable, unless it is empty or unset, in which case it will determine an appropriate
manpath based on your $PATH environment variable. This option overrides the contents of $MANPATH.

-L locale, --locale=locale
whatis will normally determine your current locale by a call to the C function setlocale(3) which interrogates
various environment variables, possibly including $LC_MESSAGES and $LANG. To temporarily override the deter‐
mined value, use this option to supply a locale string directly to whatis. Note that it will not take effect
until the search for pages actually begins. Output such as the help message will always be displayed in the
initially determined locale.

-C file, --config-file=file
Use this user configuration file rather than the default of ~/.manpath.

-?, --help
Print a help message and exit.

--usage
Print a short usage message and exit.

-V, --version
Display version information.

EXIT STATUS
0 Successful program execution.

1 Usage, syntax or configuration file error.

2 Operational error.

16 Nothing was found that matched the criteria specified.

ENVIRONMENT
SYSTEM If $SYSTEM is set, it will have the same effect as if it had been specified as the argument to the -m option.

MANPATH
If $MANPATH is set, its value is interpreted as the colon-delimited manual page hierarchy search path to use.

See the SEARCH PATH section of manpath(5) for the default behaviour and details of how this environment vari‐
able is handled.

MANWIDTH
If $MANWIDTH is set, its value is used as the terminal width (see the --long option). If it is not set, the
terminal width will be calculated using the value of $COLUMNS, and ioctl(2) if available, or falling back to
80 characters if all else fails.

FILES
/usr/share/man/index.(bt|db|dir|pag)
A traditional global index database cache.

/var/cache/man/index.(bt|db|dir|pag)
An FHS compliant global index database cache.

/usr/share/man/.../whatis
A traditional whatis text database.

Manual: whatis

Related Commands: