Working with commands

type

• It is used to display a command's type.
• Usage: type command
• Examples:
  • type ls
  • type cd
  • type cp

which

• It is used to display an executables location.
• Usage: which nameOfExecutable
• Examples:
  • which wireshark
  • which stegseek
  • which tcpdump

help

• It is used to get help for shell builtins.
• Usage: help command
• Examples:
  • help cd
  • help type

-h or --help

• It is a flag which is supported by many shell builtins and executables to display help for that command or executable.
• Usage: command --help
• Examples:
  • mkdir --help
  • wireshark --help

man

• It is used to dispay the manual or man page of a command.
• Usage: man command
• Examples:
  • man ls
  • man rm
  • man bash

apropos

• It is used to display appropriate commands using a search term.
• Usage: apropos searchTerm
• Examples:
  • apropos network
  • apropos forensics

whatis

• It is used to display the name and one-line description of a man page matching a specified keyword.
• Usage: whatis keyword
• Example:
  • whatis ls

alias

• It is used to give a special name to a command or a bunch of commands combined.
• Usage: alias name='command1; command2; command3...'
• To list all aliases just write alias.
• Example:
  • alias foo='cd ~/Desktop/; mkdir test'
  • alias

unalias

• It is used to remove an alias.
• Usage: unalias aliasName
• Example:
  • unalias foo