Man page 1 : whatis

whatis - display manual page descriptions

whatis [  -dlhvV  ] [  -r  |  -w\c  ] [  -s section  ] [  -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 namematched. namemay contain wildcards ( -w ) or be a regular expression ( -r ). Using these options, it may be necessary to quote the nameor 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 manpathis a manual page hierarchy such as /usr/man .

-d, --debug

    Print debugging information.

-v, --verbose

    Print verbose warning messages.

-r, --regex

    Interpret each nameas a regular expression. If a namematches 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 nameas a pattern containing shell style wildcards. For a match to be made, an expanded namemust 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 section, --section section
      Search only the given manual section. If sectionis 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 sectionhas an extension, for example "3perl", then the list will only include pages in that exact part of the manual section.

-m system\c  [ ,. . . ]  , --systems= system\c  [ ,. . . ] 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

R NewOS . The systemspecified 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
      .B whatis will normally determine your current locale by a call to the C function

R 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 localestring directly to

R 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.

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.

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

R ioctl (2) if available, the value of $ COLUMNS , or falling back to 80 characters if all else fails.

• /usr/share/man/index.(bt|db|dir|pag)
      A traditional global indexdatabase cache.
• /var/cache/man/index.(bt|db|dir|pag)
      An FHS compliant global indexdatabase cache.
• /usr/share/man/ . . . /whatis
      A traditional

whatis text database.

R apropos (1),

R man (1),

R mandb (8).