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APROPOS(1)                                        Manual pager utils                                       APROPOS(1)



NAME
       apropos - search the manual page names and descriptions

SYNOPSIS
       apropos [-dalv?V] [-e|-w|-r] [-s list] [-m system[,...]] [-M path] [-L locale] [-C file] keyword ...

DESCRIPTION
       Each manual page has a short description available within it.  apropos searches the descriptions for instances
       of keyword.

       keyword is usually a regular expression, as if (-r) was used, or may contain  wildcards  (-w),  or  match  the
       exact  keyword  (-e).  Using these options, it may be necessary to quote the keyword or escape (\) the special
       characters to stop the shell from interpreting them.

       The standard matching rules allow matches to be made against the page name and word boundaries in the descrip‐
       tion.

       The database searched by apropos is 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.

OPTIONS
       -d, --debug
              Print debugging information.

       -v, --verbose
              Print verbose warning messages.

       -r, --regex
              Interpret each keyword as a regular expression.  This is the default behaviour.  Each keyword  will  be
              matched  against  the  page names and the descriptions independently.  It can match any part of either.
              The match is not limited to word boundaries.

       -w, --wildcard
              Interpret each keyword as a pattern containing shell style wildcards.  Each  keyword  will  be  matched
              against  the page names and the descriptions independently.  If --exact is also used, a match will only
              be found if an expanded keyword matches an entire description or page name.  Otherwise the  keyword  is
              also allowed to match on word boundaries in the description.

       -e, --exact
              Each keyword will be exactly matched against the page names and the descriptions.

       -a, --and
              Only  display  items  that match all the supplied keywords.  The default is to display items that match
              any keyword.

       -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[,...]

       -L locale, --locale=locale
              apropos 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  apropos.   Note
              that  it will not take effect until the search for pages actually begins.  Output such as the help mes‐
              sage 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 an ioctl(2) if available, the value of $COLUMNS, or
              falling back to 80 characters if all else fails.

       POSIXLY_CORRECT
              If $POSIXLY_CORRECT is set, even to a null value, the default apropos search will  be  as  an  extended
              regex (-r).  Nowadays, this is the default behaviour anyway.

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

2.6.3                                                 2012-09-17                                           APROPOS(1)