To send a SIGINT, you need to look up its numerical value on your system and send that:

kill $sig_of{INT}, $pid;     # 2 on my system, type 'kill -l' to check yours

Are you sure you need to send the signal to yourself, and not the child process? You probably want to fork + exec off the child, take note of the pid, and kill that off.

Update: Correct bogus reference to %SIG