I found this (more or less) in Gtk::cookbook (comes with Gtk-Perl... just do man Gtk::cookbook). Sorry, no ideas about "transparent" windows (though I'm not 100% sure what you mean by "transparent"). 

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

use Gtk '-init';

my $mw = Gtk::Window->new();
my $lb = Gtk::Label->new("This is only a test.");

$mw->border_width(5);
$mw->add($lb);
$mw->signal_connect('key_press_event', sub { Gtk->main_quit; 1 });


###############################

# Note that you have to realize it
# before you can access $mw->window
$mw->realize;
$mw->window->set_decorations(0);

###############################


$mw->show_all;

Gtk->main;

[download]

bbfu
Black flowers blossum
Fearless on my breath

In reply to (bbfu) Re: Transparent Transient Windows with Gtk-Perl by bbfu
in thread Transparent Transient Windows with Gtk-Perl by stefan k

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