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

use Tk;
use Win32::KeyState qw(:get);

my $main =  new Tk::MainWindow;
$main->geometry('1030x740');

my $vis = 1;

sub read_stuff
 {
  &switch_vis if ((GetKeyState(0x1b) & 1) == 1);
 }
$handler = $main->repeat(500, \&read_stuff);


sub switch_vis
 {
  if($vis == 0)
   {
    $vis = 1;
    $main->deiconify;
   }
  else
   {
    $vis = 0;
    $main->iconify;
   }
 }

MainLoop;