whatis - display one-line manual page descriptions


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


   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.


   -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

   -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.


   0      Successful program execution.

   1      Usage, syntax or configuration file error.

   2      Operational error.

   16     Nothing was found that matched the criteria specified.


   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.


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


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


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