#!/usr/bin/perl

use strict;
use warnings;
use Tk;

my $mw = tkinit;
my $var = "test";

my $entry = $mw->Entry( -textvariable => \$var )->pack;
$entry->bind( '<Return>', \&aufruf );

MainLoop;

sub aufruf{
    print "Hallo ",$entry->get,"\n";
}