Gdk/X integration

[Carl Nygard <cjnygard fast net>]

I need to use gdk_pixmap_foreign_new_for_display() to get something
suitable to wrap() for Gdk::Pixbuf output.  I seem to need to get the
GdkDisplay*, but all I have is the Display*.  gdk_x11_lookup_xdisplay()
seems to fail, so I'm wondering if I need to create instead of lookup,
but I can't figure out how from the docs.

Help?

Regards,
Carl