CS 279 - Week 10 Lab - 10-24-12

(OK, created this after-the-fact, based on the screen
 shot of our playing with PS1 during lab.)

*   you can set environment variable PS1 to change your
    UNIX/Linux command prompt.
    *   before you start playing with it, it is advisable
        to SAVE the current value for more convenient
	resetting back:

SAVE_PS1=$PS1

    *   (change it in your current session? it only stays
        in effect for the current session, because changes
	to environment variables only change the current
	session's copy of those variables.)

    *   But if you find a prompt style you like,
        you can add that setting of PS1 to your .bashrc
	file, so it is set whenever you start up an
	interactive bash shell.

*   so:

$ PS1="moo> "
moo> 

    ...changes your command prompt to "moo> ".

*   there are many special characters you can use to
    insert useful values into your command prompt --
    a list of these can be found in the GNU Bash Reference
    Manual, at:
http://www.gnu.org/software/bash/manual/bashref.html#Printing-a-Prompt

*   here are a few:
    \a   - causes a bell "character" to be played
           (makes a distinctive "thunk" on my Mac).

    \d   - displays date as Day Mon DD.

    \l   - gives number of device.

    \n   - inserts a newline into prompt.

    \t   - inserts time in 24-hour format, HH:MM:SS.
    \T   - inserts time in 12 hour format, HH:MM:SS.

    \v   - inserts the bash version number.
    \V   - inserts the bash version and patch number.

    \!   - inserts the current history command number.

    \u   - inserts the username.

    \h   - inserts the hostname (up to the first .).

    \W   - inserts the basename of the current working directory.

    ...and you can find more at that link mentioned earlier.