Suggestion to improve /etc/bashrc
---------------------------------

Currently, /etc/bashrc has this:

    case $TERM in
        xterm*)
            PROMPT_COMMAND='echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD\ 
007"'
            ;;
        *)
            ;;
    esac



The behavior is fine; however, I administer multiple systems and 
would like to have an easier way to modifiy the $PROMPT_COMMAND

I would like those lines to be replaced with something like this:

    case $TERM in
        xterm*)
        PROMPT_COMMAND=/usr/bin/prompt-xterm
            ;;
        *)
        PROMPT_COMMAND=/usr/bin/prompt-default
            ;;
    esac


in /usr/bin/prompt-xterm, I have this:  

echo -ne "\033]0;${USER}@${HOSTNAME}:${PWD}\007"
/usr/bin/prompt-default


in /usr/bin/prompt-default is where I have my own stuff.


Additional Info/History
-----------------------
I did this because I wanted a more intelligent mail-notification 
system.  So many times I get the message "New mail has arrived." when
it hasn't.  Sometimes I don't get notified.  Sometimes I get notified
on two different ssh sessions.

I use qmail.  What I did was this:

in my /etc/qmail/control/aliasempty file I put this:

./Maildir/
|echo `date '+%s'` >$HOME/.newmail


(When new mail arrives, qmail puts the date the mail arrived in 
$HOME/.newmail.  This has the format of seconds since 00:00:00 Jan 1,
1970.  If another message arrives, the date of the latest message
overwrites any previous values in $HOME/.newmail.)

In /usr/bin/prompt-default, I have this:

if [ -f $HOME/.newmail ]; then
        ARRIVED=`cat $HOME/.newmail`
        rm $HOME/.newmail

        AGE=$[`date '+%s'`-$ARRIVED]

        if [ $AGE -lt 0 ] ; then
                NOTIFY="New mail has arrived."
        elif [ $AGE -eq 0 ] ; then
                NOTIFY="New mail just arrived."
        else
                if [ $AGE -lt 60 ] ; then
                        QTY=$AGE
                        UNIT="second"
                elif [ $AGE -lt 3600 ]; then
                        QTY=$[($AGE+30)/60]
                        UNIT="minute"
                elif [ $AGE -lt 86400 ]; then
                        QTY=$[($AGE+1800)/3600]
                        UNIT="hour"
                else
                        QTY=$[($AGE+43200)/86400]
                        UNIT="day"
                fi

                if [ $QTY -ne 1 ]; then
                        UNIT="$UNIT"s
                fi

                NOTIFY="New mail arrived $QTY $UNIT ago."
        fi

        echo
        echo " * $NOTIFY"
        echo

fi

(Every time I press return in an interactive bash shell, the system
does a quick check to see if $HOME/.newmail has arrived.  If so, it
calculates how long ago it arrived and formats it into a nice, user-
friendly format like this:

 * New mail arrived 7 minutes ago

I receive this message only once, on only one terminal, and it is
always a true statement.)

I have my email client renamed (mutt --> mutt-binary) and run from a 
script (mutt).  In the mutt script, after the binary has exited, it 
deletes $HOME/.newmail so that I don't hear about email received while
I was reading mail.  

I'm not proposing that everyone adopt my email notification system (it
is very nice, though).  I just want a generic way for everyone to be
able to implement their own $PROMPT_COMMAND enhancements.