apropos

Additional Notes

apropos searches manual page names and short descriptions. It is useful when you know the task but not the command name.

It searches the same manual-page database used by man -k on many systems.

Syntax

apropos [options] keyword...

Parameters

• keyword: Word or regular expression to search for in manual page names and descriptions.
• options: Matching and section filters.

Common Options

• -e: Match each keyword exactly.
• -a: Require all keywords to match.
• -s SECTION: Search only a manual section.
• -r: Treat keywords as regular expressions.
• -w: Use wildcard matching.

Examples

apropos password

Find manual pages related to passwords.

apropos -a copy file

Find entries matching both words.

apropos -s 1 network

Search user-command manual pages for network-related entries.

man -k ssh

Equivalent style of search on many systems.

Practical Notes

• If results are empty, the manual database may need to be updated with mandb.
• Use whatis COMMAND when you already know the command name.
• Manual section 1 is user commands, 5 is file formats, and 8 is administration commands.