#!/usr/bin/perl
use strict;
use warnings;
use Time::Local;
use Time::HiRes qw[ time ];
use POSIX ":sys_wait_h";

my $timeout = 3;

my $Command = qq(echo 'Hallo, sleeping for 120 seconds ...'; sleep 120 2>&1); 
my $pid = open (COMMAND, '-|', "$Command");
print "ran command with pid=$pid\n";
my $iters = 0;
while (kill 0, $pid) {
	eval {
		local $SIG{ALRM} = sub { print "resetting alarm $timeout\n"; alarm($timeout); die("TimerTriggerStatus\n"); };
	        if( ! $iters++ ){ print "setting alarm for the first time...\n"; alarm($timeout); }
		print "sleeping for $timeout and then will check command's output...\n";
		sleep $timeout;
		print "now I may block for a long time waiting for command's output...\n";
		print "command: ".<COMMAND>."\n";
	};
	print "eval exited with this: ".$@."\n";
}