Shell Programming and Scripting

#!/bin/bash
while true
if [ -z `ps -p 1234` ] #process is no longer reporting as up
echo "process 1234 has fell"
exit 1 # exit script
fi
sleep 1
#end of script

#!/bin/bash

pid=${1:?Usage $(basename $0) pid}
while true
do
    if ! kill -0 $pid 2>/dev/null; then #process is no longer reporting as up
        echo "process $pid has fell"
        exit 1 # exit script
    fi
    sleep 1
done