WHATIS(1) Manual pager utils WHATIS(1)
whatis - display one-line manual page descriptions
whatis [-dlv?V] [-r|-w] [-s list] [-m system[,...]] [-M path] [-L
locale] [-C file] name ...
Each manual page has a short description available within it. whatis
searches the manual page names and displays the manual page descrip-
tions 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 data-
base 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.
Print debugging information.
Print verbose warning messages.
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 data-
Interpret each name as a pattern containing shell style wild-
cards. 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 database searches.
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 sim-
ple section, for example "3", then the displayed list of
descriptions will include pages in sections "3", "3perl", "3x",
and so on; while if an entry in list has an extension, for exam-
ple "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 system's manual
page names, they can be accessed using this option. 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 oper-
ating system's manual page names, include the system name man in
the argument string. This option will override the $SYSTEM
-M path, --manpath=path
Specify an alternate set of colon-delimited manual page hierar-
chies to search. By default, whatis uses the $MANPATH environ-
ment variable, unless it is empty or unset, in which case it
will determine an appropriate manpath based on your $PATH envi-
ronment variable. This option overrides the contents of $MAN-
-L locale, --locale=locale
whatis will normally determine your current locale by a call to
the C function setlocale(3) which interrogates various environ-
ment variables, possibly including $LC_MESSAGES and $LANG. To
temporarily override the determined 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
Print a help message and exit.
Print a short usage message and exit.
Display version information.
0 Successful program execution.
1 Usage, syntax or configuration file error.
2 Operational error.
16 Nothing was found that matched the criteria specified.
SYSTEM If $SYSTEM is set, it will have the same effect as if it had
been specified as the argument to the -m option.
If $MANPATH is set, its value is interpreted as the colon-delim-
ited manual page hierarchy search path to use.
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, an ioctl(2) if
available, or falling back to 80 characters if all else fails.
A traditional global index database cache.
An FHS compliant global index database cache.
A traditional whatis text database.
apropos(1), man(1), mandb(8)
Fabrizio Polacco (email@example.com).
Colin Watson (firstname.lastname@example.org).
2.8.4 2018-07-27 WHATIS(1)