list of goocanvas items

[control H <control h gmail com>]

Dear list,

I try to find all items belonging to a canvas. The function which
comes close to what I'm looking for is goo_canvas_get_items_in_area()
however, it doesn't allow me to find _all_ items, regardless whether
they're inside or outside some area. I could use an "infinite" big
area to capture all items but I don't like to put in some magic
numbers. Is there another way to find all items?