#!/usr/bin/perl -w
use strict;
use Tk;
use Tk::Text;
use Tk::IO;

my $mw = MainWindow->new( -width => 200, -height => 200);
my $textwidget = $mw->Text()->pack( -expand => 1, -fill => 'both');
tie *STDOUT, ref $textwidget, $textwidget;

my $label = $mw->Label( -text => ".")->pack( -fill => 'x');
my $b = $mw->Button( -text => "start", -command => \&start)->pack( -fi
+ll => 'x');

## just showing that Tk events are actually handled all the time
my $i = 0;
my @thing = qw( . o O o );
$mw->repeat( 100 => sub { $label->configure( -text => $thing[$i++] x 2
+0); $i = 0 if $i == @thing });



sub start {
  # this catches the output of the child process and 
  # sends it to (tied) STDOUT of this process
  my $io = Tk::IO->new( -linecommand => sub { print @_ }, -childcomman
+d => sub { print "EOF\n" } );

  $io->exec(q(perl -e '$|=1; for (0 .. 10) { print "$_\n"; sleep 1 }')
+);
}

MainLoop;
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