#!/usr/bin/perl -w
use strict;

my $time_to_die=0;
my $timeout=5; #in seconds 

$SIG{ALRM} = sub { $time_to_die=1; };

alarm($timeout);
while(!$time_to_die){
#tasks here 
print time,"\n";
}

#will allow while loop to complete 
#after $SIG{ALRM} is received