gdk_window_set_child_shapes()

[Andrew Shafer <shafer realmsys com>]

Does anyone use this function?

Can I get a working example?

I have been through the archives and I haven't find any useful
information.

I want to be able to call gtk_widget_shape_combine_mask on a bunch of
children and then have the toplevel window be the union of these
children.  From the description gdk_window_set_child_shapes() seems like
the solution, but calling it just makes the window collapse to a single
dot. (although xwininfo says that all the children exist in their proper
dimensions) 

gdk_window_merge_child_shapes() is even stranger because then I get a
truncation of the top level rectangle.

Does anyone actually have experience using this function?

Regards,

Andrew Shafer