How do I get the GdkWindow from a GtkWindow

[Jens <axon isl is>]

Hi

I want t be able to grab the mouse pointer and confine it to a window. I
plan on using the function gdk_pointer_grab but the problem is I don't
have a GdkWindow pointer, just a GtkWindow pointer as I am using GTK+ to
create my widgets.

Is it possible to get the GtkWindow that GdkWindow is using and pass
that to the grab function?

If not, is there some other way in GTK+ that I can use to grab the
pointer?

Thanks,
Jens P
Axon ehf.