#!/usr/bin/perl
use strict;
use Storable qw(freeze thaw);

BEGIN{
	$SIG{USR1}=\&drdy;
}

my @datastore=();

sub drdy { 
	print "Signal!\n";
	my $d=<STDIN>;
	print $d."\n";
	push @datastore,$d;		

	$SIG{USR1}=\&drdy;
}

while (1) {
	sleep 1;
	print shift @datastore if (scalar @datastore);
}