Retrieving title of GdkWindow

["David Menendez" <dave sycamore us>]

I've wrapped a "foreign window" with a GdkWindow using
gdk_window_foreign_new(id), and I need to retrieve the window's title.  I
can't figure out how to retrieve the window's title from the available
GdkWindow functions.

There's a function to SET the title, but not to GET the title.  And there is
no function to retrieve a GdkWindowAttr structure for the window that I see.

Do I have to resort to making an X11-level call to get the window's title?
If so, I assume that's not as portable as having a GDK call - is there a
reason such a function doesn't exist for a GdkWindow?