Linuxdoc Linux Questions
Click here to ask our community of linux experts!
Custom Search

12.9. The Elegant Useless Clock Prompt

This is one of the more attractive (and useless) prompts I've made. Because many X terminal emulators don't implement cursor position save and restore, the alternative when putting a clock in the upper right corner is to anchor the cursor at the bottom of the terminal. This builds on the idea of the "termwide" prompt above, drawing a line up the right side of the screen from the prompt to the clock. A VGA font is required.

Note: There is an odd substitution in here, that may not print properly being translated from SGML to other formats: I had to substitute the screen character for \304 - I would normally have just included the sequence "\304", but it was necessary to make this substitution in this case.


#   This prompt requires a VGA font.  The prompt is anchored at the bottom
#   of the terminal, fills the width of the terminal, and draws a line up
#   the right side of the terminal to attach itself to a clock in the upper
#   right corner of the terminal.

function prompt_command {
#   Calculate the width of the prompt:
hostnam=$(echo -n $HOSTNAME | sed -e "s/[\.].*//")
#   "whoami" and "pwd" include a trailing newline
#   Add all the accessories below ...
let promptsize=$(echo -n "--(${usernam}@${hostnam})---(${PWD})-----" \
                 | wc -c | tr -d " ")
#   Figure out how much to add between user@host and PWD (or how much to
#   remove from PWD)
let fillsize=${COLUMNS}-${promptsize}
#   Make the filler if prompt isn't as wide as the terminal:
while [ "$fillsize" -gt "0" ] 
   # The A with the umlaut over it (it will appear as a long dash if
   # you're using a VGA font) is \304, but I cut and pasted it in
   # because Bash will only do one substitution - which in this case is
   # putting $fill in the prompt.
   let fillsize=${fillsize}-1
#   Right-truncate PWD if the prompt is going to be wider than the terminal:
if [ "$fillsize" -lt "0" ]
   let cutt=3-${fillsize}
   newPWD="...$(echo -n $PWD | sed -e "s/\(^.\{$cutt\}\)\(.*\)/\2/")"
#   Create the clock and the bar that runs up the right side of the term
local LIGHT_BLUE="\033[1;34m"
local     YELLOW="\033[1;33m"
#   Position the cursor to print the clock:
echo -en "\033[2;$((${COLUMNS}-9))H"
echo -en "$LIGHT_BLUE($YELLOW$(date +%H%M)$LIGHT_BLUE)\304$YELLOW\304\304\277"
local i=${LINES}
echo -en "\033[2;${COLUMNS}H"
#   Print vertical dashes down the side of the terminal:
while [ $i -ge 4 ]
   echo -en "\033[$(($i-1));${COLUMNS}H\263"
   let i=$i-1

let prompt_line=${LINES}-1
#   This is needed because doing \${LINES} inside a Bash mathematical
#   expression (ie. $(())) doesn't seem to work.


function clock3 {
local LIGHT_BLUE="\[\033[1;34m\]"
local     YELLOW="\[\033[1;33m\]"
local      WHITE="\[\033[1;37m\]"
local LIGHT_GRAY="\[\033[0;37m\]"
local  NO_COLOUR="\[\033[0m\]"

case $TERM in

$YELLOW\$(date \"+%a,%d %b %y\")\