RECOMMENDED ARTICLES

• My .emacs configuration file.
• Wodim commands. Burning an iso.
• Rpm Package Management Quick Reference
• Installing emacs from source code.
• dpkg, apt, aptitude quick reference.
• Cleaning iptables rules and allowing access to all.
• Some emacs lisp functions.
• List all storage devices in the system.

MANPAGES and MAN COMMANDS

man
An interface to the on-line reference manuals.
$man ls

apropos
search the manual page names and descriptions.

There are three search options:

• use keyword as regular expression (default method):
  $apropos -r ind
• use wildcards in keyword:
  $apropos -w 'fin*'
• match exact keyword:
  $apropos -e 'find'

$man -k equals apropos command.

whatis
displays man page descriptions.

This command can also use wildcards -w or regular expressions -r.

$man -f provides whatis command.

mandb
create or update the manual page index caches.

woman emacs man page reader
M-x woman

Man page SECTIONS

Manpages are classified into several sections.

• 1. Executable programs or shell commands
• 2. System calls (functions provided by the kernel)
• 3. Library calls (functions within program libraries)
• 4. Special files (usually found in /dev)
• 5. File formats and conventions eg /etc/passwd
• 6. Games
• 7. Miscellaneous (including macro packages and conventions), e.g. man(7), groff(7)
• 8. System administration commands (usually only for root)
• 9. Kernel routines [Non standard]

Usually man searchs in all available sections, but it can be specified to search only in some sections. e.g:
$man 1 ls
$man 7 man
$man 1 man

REFERENCE

$man man
$man apropos
$man whatis
$man mandb