Abort a program after a certain time

Question

I'm trying to develop a test case for a program, and would like to fail the test case if it runs over 4 seconds. How can this be done on linux? (I'm using Ubuntu)

I know I can time the execution and fail it time > 4, but that's just a bad approach.

Thanks!

Answer 1

(shell script solution) Runs your testcase in background, get the PId of it, and checks after 4 seconds if the process is still running.

wait_seconds=4
interval_seconds=0.5
run_your_test_case &
pid=$!
max=`expr "$wait_seconds / $interval_seconds"`
for (( I=0; I<$max; I++ ));do
    if kill -0 $pid >/dev/null;then
       echo 'test failed'
    else
       echo 'test ok'
       break
    fi
    sleep $interval_seconds
done

Answer 2

You could also do something like <command> & sleep 5 && kill ${!}