apropos

Overview

The apropos command searches the manual page names and descriptions for a keyword or regular expression. It’s useful for finding commands when you don’t know their exact names.

Syntax

apropos [options] keyword ...

Common Options

Option Description
-a Match all keywords
-r Use regex for matching
-s sections Search specific manual sections
-l List format output
-w Match whole words only
-e Use exact match
--and Match all keywords (AND search)
--or Match any keyword (OR search)

Key Use Cases

  1. Find relevant commands
  2. Discover command alternatives
  3. Search command descriptions
  4. Learn about system features
  5. Command exploration

Examples with Explanations

Example 2: Multiple Keywords

apropos -a user password

Find commands related to both user and password

Understanding Output

Format:

command (section) - description

Example:

passwd (1) - change user password

Common Usage Patterns

  1. Find command by function:

    apropos "change password"

  2. Search specific section:

    apropos -s 1 editor

  3. Exact match:

    apropos -e command

Performance Analysis

  • Database-driven searches
  • Regular expression support
  • Section-specific searches
  • Boolean operations
  • Multiple keyword search

Additional Resources