$menubar = $top->Menu;
   $file_menu = $menubar->cascade(-label => "~File");
   $file_menu->command(-label => "Restart", -command => \&Restart);
   $file_menu->command(-label => "Exit", -command => \&Exit);

   $file_menu = $menubar->cascade(-label => "Filter");

   $file_menu->command(-label => "All", -command => sub {$fname = "machines"; &Restart});
   $file_menu->command(-label => "HP-UX", -command => sub {$fname = "machines.HPUX"; &Restart});
   $file_menu->command(-label => "Linux", -command => sub {$fname = "machines.Linux"; &Restart});