bug#25875: 26.0.50; Hang logging out of MS-Windows

[Ken Brown <kbrown@cornell.edu>]

On 2/28/2017 10:36 AM, Eli Zaretskii wrote:
>> From: Richard Copley <rcopley@gmail.com>
>> In the nine months since Ken's change, I've noticed a problem with
>> Emacs twice.
>
> Then I guess it would be better to just push those changes and see if
> they do any harm.

>> I can't get my head around the idea. If we don't care whether or not
>> the action in question has finished when SendMessage returns,
>> then why are we using SendMessage? And if we do care, then
>> shouldn't I expect weird bugs caused by timing out when the system's
>> under load?
>
> If a window procedure doesn't process messages for more than 5 sec,
> Windows will put "Not Responding" on its caption bar.  So I think the
> 100 msec number in Ken's patch should be changed to something like
> 6000, and then we are fine, because even on a busy system this should
> be long enough.  And if Emacs (and the OS) is about to shut down, it's
> even less of a problem to ignore a message that timed out, IMO.

I've pushed the patch (with 6000 msec) and am closing the bug.  Richard, 
please reopen if you ever see the problem again.

I'm leaving the sleep(1000) in w32_wnd_proc, at least for now, because I 
want to find out about it if the problem isn't really fixed.  Maybe I'll 
add a FIXME comment.

Ken