#!/usr/local/bin/perl -w

use Tk;
use subs qw/beep/;
use strict;

my $mw1 = MainWindow->new;
my $mw2 = MainWindow->new(-screen => $ARGV[0] ||= $ENV{DISPLAY});

$mw1->Button(-text => 'Bell', -command => [\&beep, $mw1])->pack;
$mw1->Button(-text => 'Bell', -command => [\&beep, $mw2])->pack;
$mw1->Button(qw/-text Quit -command/ => \&exit)->pack;

MainLoop;

sub beep {shift->bell}