#!/usr/bin/perl
use strict;
use warnings;
use Time::HiRes 'usleep';
my $num_processes = 10;
my $signals_per_process = 1000;
$| = 1;
my @pids;
$SIG{USR2} = sub { print "parent received ".Time::HiRes::time().$/ };

FORKS:
while ($num_processes > 0) {
	my $parent = $$;
	if (my $pid = fork()) {
		push @pids, $pid;
	} else {
		$SIG{USR1} = sub { print $$." received ".Time::HiRes::time().$/; };
		while (1) {
			usleep(rand(20));
			print "parent signalled ".Time::HiRes::time().$/;
			kill('USR2',$parent) or exit;
		}
		exit;
	}
	$num_processes--;
}

for (1..$signals_per_process) {
      PROCESS:
	foreach my $id (@pids) {
		print $id." signalled ".Time::HiRes::time().$/;
		kill("USR1", $id);
		usleep(rand(20));
	}
}
exit;