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 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
       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.

       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.

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

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

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



2.9.4                              2021-02-08                          WHATIS(1)