You can use fork/exec instead of system like this: 
#!/bin/perl

use strict;
use warnings;

my $pid = fork();

unless ($pid) {
    exec "nc -l 7777" or die;
}

local $SIG{ALRM} = sub {
    print "Command timed out!\n";
    kill 9, $pid;
};

alarm 2;
waitpid $pid, 0;
alarm 0;

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In reply to Re: Kill a command launched within script by zwon
in thread Kill a command launched within script by ceweldon

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