Eli Zaretskii <eliz@gnu.org> writes:

>> The order is not important, I just didn't know where to look to get
>> a frame; sorry for the noise.  I now use ‘Fnext_frame’.
>
> Unfortunately, I don't think you cannot use Fnext_frame here.  The
> function which calls it, w32_wnd_proc, runs in a separate thread, so
> it generally cannot access Lisp objects safely.  However, it is okay
> to traverse the list of the frames, as w32_window_to_frame does, see
> the comment at the beginning of w32_wnd_proc.  So I think you could
> use a similar loop with FOR_EACH_FRAME, and use some frame from there,
> perhaps the first one?
>
> Alternatively, and maybe more safely, you could call
> maybe_pass_notification from w32_destroy_window, which is called from
> the main (a.k.a. "Lisp") thread, so then you can use Fnext_frame
> (actually, I would make next_frame extern instead of static and call
> it directly).  This means the notifications are passed a bit before
> the frame is actually deleted by the OS, but I think this is okay?

I went with the first option, using FOR_EACH_FRAME, because I am not
sure about the safety of modifying the kbdhook struct from the other
thread.

Regards,
Raffael