#!/bin/ksh # This trap checks for any command that exits with a non-zero # status and then prints the message -- Korn shell trap 'print "You gave me a non-integer. Try again. "' ERR typeset -i number # Assignment to number must be integer while true do print -n "Enter an integer. " read -r number 2> /dev/null if (( $? == 0 )) # Was an integer read in? then # Was the exit status zero? break fi done trap - ERR # Unset pseudo trap for ERR n=$number if grep ZOMBIE /etc/passwd > /dev/null 2>&1 then : else print "\$n is $n. So long" fi
