apropos

Overview

The apropos command searches the manual page names and descriptions for a specified keyword. 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
-e Use exact match
-r Use regex pattern
-s sections Search sections
-l Long output format
-w Show page locations
-C Case sensitive
-L locale Set locale
-M path Set manual path
-S Sort output
-v Verbose output

Manual Sections

Section Content
1 User commands
2 System calls
3 Library functions
4 Special files
5 File formats
6 Games
7 Miscellaneous
8 System administration
9 Kernel routines

Key Use Cases

  1. Command discovery
  2. Function lookup
  3. Documentation search
  4. Topic exploration
  5. Learning tools

Examples with Explanations

Example 2: Multiple Keywords

apropos -a search file

Match all keywords

Example 3: Exact Match

apropos -e chmod

Exact command match

Common Usage Patterns

  1. General search:

    apropos keyword

  2. Section search:

    apropos -s 1 keyword

  3. Regex search:

    apropos -r 'pattern'

Search Tips

  1. Use keywords
  2. Try synonyms
  3. Check sections
  4. Use regex
  5. Combine terms

Additional Resources

Best Practices

  1. Be specific
  2. Use options
  3. Check all results
  4. Verify matches
  5. Document findings

Output Format

  1. Command name
  2. Section number
  3. Description
  4. Manual path
  5. Match context

Troubleshooting

  1. No matches
  2. Too many results
  3. Wrong section
  4. Database issues
  5. Locale problems