bash cript to run cudahashcat as screensaver

Hi, I am trying to make a bash script that runs cudahashcat when xscreensaver goes on, and I am looking for a way to quit/exit hascat when the screensaver unblanks.
i tried various versions of killall pkill etc without luck.
i have been searching for a way to pass a 'q' to hashcat from the script to quit, also without luck. (new to bash)
thanks in advance.

my script looks like this:

!/bin/bash
process() {
while read input; do
case "$input" in

UNBLANK*)
echo "Unblank - kill cudaHascat session"

killall cudaHashcat somehow
;;

BLANK*)
echo "Blank - restore cudaHashcat session";
cudaHashcat arguments bla bla bla
;;

esac
done
}

/usr/bin/xscreensaver-command -watch | process