whatis(1) — Linux manual page


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

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

              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.

              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, and ioctl(2)
              if available, or falling back to 80 characters if all else

FILES         top

              A traditional global index database cache.

              An FHS compliant global index database cache.

              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


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
       ⟨http://git.savannah.gnu.org/r/man-db.git⟩ on 2020-07-14.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2020-07-04.)  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)url(7)urn(7)