$ perl /tmp/scratch.pl true
[child] Executing true
[child] Exiting with exit code 0.
[parent] Command has already terminated. (exit code = 0)
[parent] Terminating with exit code 0.

$ perl /tmp/scratch.pl false
[child] Executing false
[child] Exiting with exit code 1.
[parent] Command has already terminated. (exit code = 1)
[parent] Terminating with exit code 1.

$ perl /tmp/scratch.pl sleep 5
[child] Executing sleep 5
[parent] Command is still running.
[parent] Terminating with exit code 0.
  <after 5 seconds>
[child] Exiting with exit code 0.

$  perl /tmp/scratch.pl "sleep 5 ; false"
[child] Executing sleep 5 ; false
[parent] Command is still running.
[parent] Terminating with exit code 0.
  <after 5 seconds>
[child] Exiting with exit code 1.