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

my $mw = tkinit();

$mw->Button(
    -text =>  'go' ,
    -command => sub {
        $mw->Busy;
        $mw->iconify;
        $mw->withdraw;
        
        system $^X, '-MTk', '-e', 'tkinit;MainLoop' ;
        
        $mw->raise;
        $mw->deiconify;
        $mw->update;
        $mw->focus;
        $mw->Unbusy;
        $mw->focus;
        $mw->focusForce; # win32
        
        return;
    },
)->pack;

MainLoop();