Useful UNIX operating system commands

passwd	change password	finger	show current users
man command_name	help for command_name	apropos keyword	find commands related to keyword
mkdir dir_name	create directory	pwd	print (show) current directory
cd dir_name	change directory to dir_name	cd ..	go to parent directory (one level up)
ls	list files in current directory	mv old_name new_name	change name old_name to new_name
mv file_name dir_name	move file from current directory to new directory	cp old_name new_name	copy content of file old_name to file new_name
rm file_name	remove file	cat file_name	show contents of file
more file_name	show content of file page by page	logout	log out

UNIX is case sensitive.
UNIX commands can be repeated by using the up and down arrow keys on the keyboard.
Completion of commands. Suppose you want to copy the file, filename. You could type cp filename. Instead, you can type cp fil and then hit the tab key. If there are no other files that also begin with "fil", the file name will be completed. Try it!
UNIX is a multiprocess and multiuser environment that allows you to run several jobs at once and have long jobs run in you absence.

^C (control C)	kill job that is running interactively	^Z	suspend job that is running interactively
fg	foreground (resume) job that has been suspended	bg	background job that has been suspended
jobs	list jobs (running and suspendsed)	top	list processes with the highest cpu usage

To run a command in the background append & to the end of the command.
To stop a job that is running in the background, enter the command ps. Browse through the list of jobs and note the PID number of the one you wish to stop. At the prompt type kill -9 PID#.

Please send your additions and comments to Harvey Gould, hgould@clarku.edu.

Updated 9 March 2002.