_WnckWindow.parent_instance meaning
I use wnck to get all window in the system. and then i want to use atk to get window's accessibility object. I don't quite understand the meaning of parent_instance in struct _WnckWindow, and i searched libwnck whole code, but only found the declare of parent_instance, not found The location of assignment.
I want to know what's the meaning of parent_instance, how can i to get the window's accessibility object.