Section: Manual pager utils (1)
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
-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.
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