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.
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 database searches.
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 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
simple 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 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 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
operating system's manual page names, include the system name
man in the argument string. This option 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=localewhatis 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 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.
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-
delimited 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.
This page is part of the man-db (manual pager suite) project.
Information about the project can be found at
⟨http://www.nongnu.org/man-db/⟩. If you have a bug report for this
manual page, send it to firstname.lastname@example.org. This page was
obtained from the project's upstream Git repository
⟨http://git.savannah.gnu.org/r/man-db.git⟩ on 2016-07-16. If you dis‐
cover any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page, or
you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a mail
2.7.5 2015-11-06 WHATIS(1)