I think the "Stay on top" property is dependent on the Window Manager. I don't use KDE, I use fvwm2. The overrideredirect option works pretty well, but it can be intrusive since it stays on all virtual desktops. Also, you mentioned searching google, but you should be checking groups.google.com to get the tk usenet newsgroup archives.

Maybe I'm misinterpreting what you want to do, maybe you just want to call $toplevel->raise if it isn't on top? You can test for window visibility, and raise it if it isn't visible.

#!/usr/bin/perl
use Tk;

$mw = tkinit;
$t = $mw->Toplevel;
$t->withdraw;
$t->Label(-text => "Testing...")->pack;
$t->Button(
   -text => "Withdraw",
   -command => sub {$t->withdraw},
)->pack;
$t ->overrideredirect(1); #to top on all virtual desktops 

$mw->Button(
   -text => 'Test',
   -command => sub {
       $_->deiconify, $_->raise for $t;
   },
)->pack;

MainLoop;
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Also you might want to check out the Tk::Wm perldoc. The following dosn't work on fvwm2, but is reported to work on KDE.

#from comp.lang.perl.tk
#The following works, at least with KDE 2. I would be glad to #here su
+ccess reports for KDE 3.
#Regards, Slaven  Rezic

use Tk;
$top = new MainWindow;
keep_on_top($top);
MainLoop;

sub keep_on_top {
    my $w = shift;
    my($wrapper) = $w->toplevel->wrapper;
    $w->property('set', '_NET_WM_STATE', "ATOM", 32,
         ["_NET_WM_STATE_STAYS_ON_TOP"], $wrapper);
}

__END__
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