Q: GtkTree - how to get parent and grandparent text?

[Aaron Trevena <betty termisoc org>]

I have had this problem: I when a child is selected I can get its
label with the get_label_or_whatever routine, but I have difficulty
getting the value of the parents label. It gets upset when I cast the
parent to GTK_BIN because it has more than one child (or something - I
think).

Tree:

-Root
|---File A
|  |--Version 1.1
 ..
|---File B
|  |--Version 1.1
 ..

So how do I get the label/text or any data I myself have added from a
parent tree in a GtkTree? Say I have version 1.1 selected I want to know
if it is version 1.1 of File A or B.

Hope this isn't too much of a newbie question..

rgds,
A.