How do I customize my shell prompt

Last Updated: December 4, 2008

How do I customize my shell prompt?

On my machine, the prompt may look like this:
[stan@marie stan]$ _

Here "stan" is my login name, "marie" is the name of the computer, the second "stan" is the name of my current working directory, and "_" represents the cursor.

The prompt is set by the environmental variable called PS1. To display the current setting, I can use:
echo $PS1

The system−wide setting of the prompt (for all users on the system) is in the file /etc/bashrc which on my system contains such a
line:

PS1="[\u@\h \W]\$ "

To customize the prompt, I can edit the file /etc/bashrc (as root) and insert almost any text inside the quotation marks. Here is the
meaning of some special codes I may also choose to use:

\u − username of the current user (= $LOGNAME),
\h − the name of the computer running the shell (hostname),
\H − entire hostname,
\W − the base of the name of the current working directory,
\w − the full name of the current working directory,
\$ − display "$" for normal users and "#" for the root,
\! − history number of the current command,
\# − number of the current command (as executed in the current shell),
\d − current date,
\t − current time (24−hr),
\T − current time (12−hr) − bash 2.0 only,
\@ − current time (AM/PM format) − bash 2.0 only,
\s − name of the shell,
\a − sound alarm (beep),
\j − number of jobs the user has,
\n − new line,
\\ − backslash,
\[ − begin a sequence of non−printable characters,
\] − end a sequence of non−printable characters,
\nnn − the ASCII character corresponding to the octal number nnn.
$(date) − output from the date command (or any other command for that matter),

Here is an example on how to add colour. See the next chapter for details about colour:

PS1="\[\033[1;32m\][\u@\h \W]\$\[\033[0m\] "

There is also the second−level prompt, set by a variable called PS2. The shell uses the second level prompt when it expects additional input, and on my system the secondary prompt is "> ". I don't worry too much about PS2, but if I did I could set it the same way as PS1. There are even PS3 and PS4, but these are rarely seen.