How to kill process after x idle min?

Shell Programming and Scripting
1

I need a script to kill those process id whose idle time is more than 30min
plz help me

2

Take a look here ... http://www.unix.com/shell-programming-scripting/21593-check-process.html

3

[[ -z "$1" ]] && echo "Usage: $0 pid" && exit 1

[[ "$1" != +([0-9]) ]] && echo "$1 is not a valid pid" && exit 1

PID="$1"
W=$(which w)
PS=$(which ps)
SED=$(which sed)
AWK=$(which awk)

TTY=$($PS -o tty4 $PID)
TTNo=$(echo "$TTY" | $SED -e '/TTY/d')

TIME=$($W | $SED -n -e "/pts\/$TTNo/p" | $AWK '{ print $5 }')

echo $PID has been idle for $TIME

[[ $TIME = *day* ]] && echo "Killing $PID" && kill -9 $PID && exit 0

IDLE=${TIME%%:*}

[[ $IDLE -gt 30 ]] && echo "Killing $PID" && kill -9 $PID && exit 0

it doesn't work.....

4

plz ne one help me!!
I need a script to kill those process id whose idle time is more than 30min
plz help me