How do I change my system prompt? 




  







"The prince wants your daughter for his wife."

"Well, tell him his wife can't have her." 

- Blackadder III 











	
	
	Step 1







To edit/change your system prompt, you need to edit your 

.*rc file in your home directory.  Of course, the .*rc file
will be different depending on your current login shell.
I strongly recommend you to read some information on
the differences among login

shells before changing your system prompt.



You can find out your current login shell by typing





$ echo $SHELL





(yes, $SHELL in uppercase)













	Shell found from "echo $SHELL"
	Description
	You need to edit this dot "rc" file
in your home directory		


	/usr/local/bin/bash
	Bourne again Shell, v1.14
	.bashrc


	/usr/local/bin/bash202
	Bourne again Shell, v2.02
	.bashrc


	/usr/local/bin/tcsh
	Tc Shell
	.tcshrc (or .cshrc)


	/usr/local/bin/zsh
	Z Shell
	.zshrc


	/bin/csh
	C Shell
	.cshrc


	/bin/ksh
	Korn Shell
	.kshrc or .profile












	
	
	Step 2







Before doing anything, it is always a good idea to make a backup file
first. (so that you can go back safely) After making backup of your .*rc
file you found from Step 1 in your home
directory, open the .*rc file using your favorite text editor (vi,
emacs, pico, nedit, dtpad, etc.), and find a line starting with 'set
prompt=' (csh and tcsh) or 'PS1' (bash, zsh and ksh) depending on your
current login shell.



Table below lists most prompt variables that you can use to choose and match 
in a given shell. 










	 
	Prompt Variable Description
	 
	csh
	ksh
	bash
	tcsh
	zsh
	 


	 
	Current working directory
	 
	$CWD
	$PWD
	\w
	%/
	%/
	 


	 
	Current working directory, with one's home directory by `~'
	 
	$CWD:t
	$PWD##*/
	\W
	%c
	%~
	 


	 
	Full hostname
	 
	N/A
	N/A
	N/A
	%M
	%M
	 


	 
	Hostname up to the first '.'
	 
	`hostname -s`
	`uname -n`
	\h
	%m
	%m
	 


	 
	Start (stop) boldfacing mode
	 
	N/A
	N/A
	N/A
	%B (or %b)
	%B (or %b)
	 


	 
	Start (stop) standout mode
	 
	N/A
	N/A
	
	%S (or %s)
	%S (or %s)
	 


	 
	Start (stop) underline mode
	 
	N/A
	N/A
	N/A
	%U (or %u)
	%U (or %u)
	 


	 
	User name
	 
	`whoami`
	`logname`
	\u
	%n
	%n
	 


	 
	The shell's tty that the user is logged in on
	 
	N/A
	N/A
	N/A
	%l
	%l
	 


	 
	The current history number
	 
	N/A
	N/A
	\!
	%h (or %!)
	%h (or %!)
	 


	 
	Name of the shell
	 
	N/A
	N/A
	\s
	N/A
	N/A
	 


	 
	Time of day in 12-hour AM/PM format
	 
	N/A
	N/A
	
	%t (or %@)
	%t (or %@)
	 


	 
	Time of day in 24-hour format
	 
	N/A
	N/A
	N/A
	%T
	%T
	 


	 
	'Precise' time of day in 12-hour AM/PM format, with seconds
	 
	N/A
	N/A
	
	%p
	N/A
	 


	 
	'Precise' time of day in 24-hour format, with seconds
	 
	N/A
	N/A
	\t
	%P
	%*
	 


	 
	The day in 'dd' format
	 
	N/A
	N/A
	
	%D
	N/A
	 


	 
	The month in 'Mon' format
	 
	N/A
	N/A
	N/A
	%w
	N/A
	 


	 
	The month in 'mm' format
	 
	N/A
	N/A
	
	%W
	N/A
	 


	 
	The year in 'yy' format
	 
	N/A
	N/A
	N/A
	%y
	N/A
	 


	 
	The year in 'yyyy' format
	 
	N/A
	N/A
	
	%Y
	N/A
	 


	 
	The date in "Weekday  Month  Date"  format
	 
	N/A
	N/A
	\d
	N/A
	N/A
	 


	 
	The date in day-dd format
	 
	N/A
	N/A
	
	
	%w
	 


	 
	The date in Mon/dd/yy format
	 
	N/A
	N/A
	N/A
	N/A
	%W
	 


	 
	The date in yy-mm-dd format
	 
	N/A
	N/A
	
	
	
	 


	 
	The weekday in 'Day' format
	 
	N/A
	N/A
	N/A
	%d
	N/A
	 


	 
	Prompt Variable Description
	 
	csh
	ksh
	bash
	tcsh
	zsh
	 




N/A = Not Available or simply I don't know.  
	If you know the correct varaible(s), please
	let me know, I'll update the table.
	TIA.


          
O.k., Here are some examples for shell prompt manipulation;







	Shell
	Prompt/PS1 setting in rc file
	Your prompt would look like


	csh
	set prompt="`whoami`@`hostname` $cwd ->"
	yoon@sycamore /usr/dt/include ->


	csh
	set prompt="$CWD:t% "
	src (i.e., CWD=/usr/local/X11/src)


	csh
	set prompt="%c1"
	
		TestDir (of /home/user/TestDir)
		

		only print last directory name in the CWD path. 
		<Contributed by Ben Herfurth>
			


	ksh
	export PS1=`logname`@`uname -n`:'$PWD'
	yoon@sonic:/home/gis/nsf


	bash
	export PS1="\u:\h [\d] "
	yoon:rhino [Tue May 26]


	bash
	export PS1="\s|\h \W] "
	bash|cedar ~\lib\OpenGL]


	tcsh
	set prompt="%B[%@]%b %n %B[%~]%b%h: "
	[12:30p] yoon [~/research]10: 


	tcsh
	set prompt = "tcsh %B[%@]%b %m[%/] "
	tcsh [2:54pm] sparky[/usr/local/lib]


	tcsh
	set prompt = "tcsh: %d-%D/%W %B[%p]%b %/ > "
	tcsh: Fri-09/04 [8:22:38pm] /var/temp >


	zsh
	export PS1="%S zsh %s in %B%m%b [%W] %~ }"
	 zsh  in maple [2/15/05] ~/project 
}


	zsh
	export PROMPT="%B%m%b %/ }"
	sequoia /home/yoon/research/FEM }
















	
	
	Step 3







Once prompt definition is save in .*rc, new prompt setting will be in effect 
next time you login.  If you wish to make the prompt change in effect right away, 
update your .*rc by sourcing it out.



For Bourne shell category (bash, zsh and ksh)





$ . .bashrc  (bash)

$ . .zshrc   (zsh)

$ . .kshrc   (ksh)





For C shell category (csh and tcsh)





$ source .tcshrc  (tcsh)

$ source .cshrc  (csh)