my $t1;
sub runbutton{
    $bar->g_grid();
    $bar->start();
    $t1 = threads->create(sub { 
        local $SIG{'KILL'} = sub { threads->exit };
        system("timer.bat"); 
        
        });
    
    $t1->set_thread_exit_only(1);
    my $start = time;
    my $end = time;
    while ($t1->is_running()) { 
        $end = time();
        $mytext = sprintf("%.2f\n", $end - $start);
        Tkx::update(); 
   }
   
    $bar->stop();
    $bar->g_grid_forget();
    $b4->g_grid_forget();
}

sub cancelbutton
{
    $t1->kill('KILL')->detach();
}