bug#32986: 27.0.50; unexpected delay in while-no-input + accept-process-output

[Eli Zaretskii]

> From: João Távora <joaotavora@gmail.com>
> Date: Mon, 8 Oct 2018 21:06:12 +0100
> Cc: 32986@debbugs.gnu.org
> 
> I will fully read and process your thorough reply later tonight or tomorrow, 
> but in the meantime let me just
> restate, or clarify in case it wasn't clear, that I expect the 30s, 15s and 
> 0.1s case to break equally as quickly,
> namely as quick as I can type the first input.
> 
> And indeed that's what happens on Linux and Mac OSX, but not on Windows.  If 
> your reply already addresses
> this apparent discrepancy, then I apologize for my premature clarification in 
> advance.

I didn't investigate the difference in behavior between Windows and
GNU/Linux, because I see similar behavior on both systems if I
neutralize all the "contaminating" factors which I described.  It is
possible that it's easier to get the 30-sec delay on Windows because
keyboard input works without signals there, and uses messaging between
2 threads running within the Emacs process.

In any case, my point is that your expectation for immediate return is
incorrect, and I tried to explain why.