use strict;
use Tk;
use Tk::Xlib;

my $desktop_nr = shift; !defined $desktop_nr and die;

my $mw = new MainWindow;
$mw->withdraw;

sub _root_property {
    my($prop) = @_;
    my(undef, @vals) = eval {
	$mw->property("get", "_NET_" . uc($prop), "root");
    };
    warn $@ if $@;
    @vals;
}

for my $prop (qw(number_of_desktops current_desktop)) {
    no strict 'refs';
    *{$prop} = sub {
	my($val) = _root_property($prop);
	$val;
    };
}

sub desktop_names {
    my($names) = eval {
	$mw->property("get", "_NET_DESKTOP_NAMES", "root");
    };
    warn $@ if $@;
    split /\0/, $names;
}

print "Desktops: " . number_of_desktops() . "\n";
print "Names: " . join(" | ", desktop_names()) . "\n";
print "Active: " . current_desktop() . "\n";

my $root = $mw->Display->RootWindow;
# Hier scheitert es:
$mw->SendClientMessage('_NET_CURRENT_DESKTOP', $$root, 32, pack('LLxxxxxxxxxxxx',$desktop_nr,time()));

print "Active now: " . current_desktop() . "\n";


__END__