whatis(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | ENVIRONMENT | FILES | SEE ALSO | AUTHOR | BUGS | COLOPHON

WHATIS(1)                  Manual pager utils                  WHATIS(1)

NAME         top

       whatis - display one-line manual page descriptions

SYNOPSIS         top

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

DESCRIPTION         top

       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         top

       -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 database 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 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=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
              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 ~/.manpath.

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

       --usage
              Print a short usage message and exit.

       -V, --version
              Display version information.

EXIT STATUS         top

       0      Successful program execution.

       1      Usage, syntax or configuration file error.

       2      Operational error.

       16     Nothing was found that matched the criteria specified.

ENVIRONMENT         top

       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.

       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         top

       /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.

SEE ALSO         top

       apropos(1), man(1), mandb(8)

AUTHOR         top

       Wilf. (G.Wilford@ee.surrey.ac.uk).
       Fabrizio Polacco (fpolacco@debian.org).
       Colin Watson (cjwatson@debian.org).

BUGS         top

       https://savannah.nongnu.org/bugs/?group=man-db

COLOPHON         top

       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 man-db-devel@nongnu.org.  This page
       was obtained from the project's upstream Git repository
       ⟨https://git.savannah.gnu.org/r/man-db.git⟩ on 2021-04-01.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2021-02-08.)  If you discover 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 to
       man-pages@man7.org

2.8.4                          2018-07-27                      WHATIS(1)

Pages that refer to this page: apropos(1)lexgrog(1)man(1)manpath(1)man(7)uri(7)