Utah Tech Computing :: IT 1100 :: Finding help in linux

IT 1100 : Introduction to Operating Systems

Command

Sample Usage

Description

type

type foo

check if an alias name already exists as a command

alias

unalias

alias

list current aliases

alias foo="cat myfile.txt | less"

create an alias for a command, like a nickname or shortcut

alias ls="ls --color"

redefine an existing command

unalias -a foo

remove an alias

type

type cd	displays the type of command
type foo	checks if a command exists

PATH

echo $PATH

PATH is a system variable. displays the locations of the command (program) files

which

which cat

find the location a particular program

--help

cat --help

get help on a program (stored in /bin or /usr/bin)

help

help cd

get help on built-in shell commands (like cd)

man

man cat

see the technical manual page of a program

info

info cat

see the human readable information page of a program

whatis

whatis ls

see a brief description of a program

apropos

apropos which	search the system for commands containing the letters which in the name or description
apropos cat	search the system for commands containing the letters cat in the name or description

Last Updated 12/15/2017