whatis(1) - display manual page descriptions
-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
-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.
-h, --help
       Print a help message and exit.
-V, --version
       Display version information.