Comment 3 for bug 916359

Got it to compile and link, but seg faults when attempting to run for me.

GDK_WINDOW_XWINDOW(gtk2)
http://developer.gimp.org/api/2.0/gdk/gdk-X-Window-System-Interaction.html#GDK-WINDOW-XWINDOW:CAPS
States another name for

GDK_DRAWABLE_XID()
--------------------------------------
#define GDK_DRAWABLE_XID(win)
Returns the X resource (window or pixmap) belonging to a GdkDrawable.
win :
 a GdkDrawable.
Returns :
 the ID of win's X resource.

which appears to match (gtk3)
gdk_x11_window_get_xid()
http://developer.gnome.org/gdk3/stable/gdk3-X-Window-System-Interaction.html#gdk-x11-window-get-xid

Window gdk_x11_window_get_xid (GdkWindow *window);
----------------------------
Returns the X resource (window) belonging to a GdkWindow.
window :
 a native GdkWindow. [type GdkX11Window]
Returns :
 the ID of drawable's X resource.

Also gtk3
GDK_WINDOW_XID()
---------------------------
#define GDK_WINDOW_XID(win)
Returns the X window belonging to a GdkWindow.
win :
 a GdkWindow.
Returns :
 the Xlib Window of win.