#!/usr/bin/perl
use warnings;
use strict;
use Tk;

startpiper();

my $mw = new MainWindow;

my $t = $mw->Scrolled("Text",-width => 80, -height => 25, -wrap => 'none');
                                             $t->pack(-expand => 1);

$mw->fileevent(\*CHILD, 'readable', [\&fill_text_widget,$t]);
MainLoop;

sub fill_text_widget {
          my($widget) = @_;
          $_ = <CHILD>;
          $widget->insert('end', $_);
          $widget->yview('end');
}

sub startpiper{
open(CHILD, "ls -la |") or die "Can't open: $!";
}