win32: get notified when gtk+ app gets killed?

["fkater googlemail com" <fkater googlemail com>]

Hi all,

on win32, in some situations (like logoff, shutdown) my gtk+
app gets killed, so I do not receive the standard gtk+ window
close/destroy signals and, in turn, cannot do clean up tasks.

For a console (!) app I've found SetConsoleCtrlHandler()
which works surprisingly well (one can set up a callback for
all interesting situations).

However, for non-console apps (with -mwindows) this does not
work.

I tried MS Window's signal() function, but it knows SIGTERM
only, not SIGKILL. No way here.

For non-console apps, MSDN says I need to set up a
WindowProc callback to catch WM_QUERYENDSESSION messages.
But to register it, it seems I need hWnd from the main
window which is somewhere hidden by gtk+...

So, is there a way to get notified somehow?

Thanks for any hint!

 Felix