Subject: Re: bug#17497: 24.4.50; TTY menu glitches

From: Thomas Dickey <[email-masked]>
Date: Thu, 05 Jun 2014 04:21:51 -0400

On Wed, Jun 04, 2014 at 08:47:42PM -0400, Stefan Monnier wrote:
> >> > Curses applications behave differently if you type those
> >> > three characters, one-by-one, because of timing.
> >> We try pretty hard to avoid using such timeouts in Emacs, so by and
> >> large this doesn't apply to Emacs at all.
> > As it happens, that rule of thumb doesn't apply to terminals:
> > https://github.com/mirrors/emacs/blob/master/src/keyboard.c
> > (it's implemented there, at any rate)
> 
> Where do you see the timeouts?

start with
	static bool get_input_pending (int);

The code's waiting for a while to ensure that it gets all of the bytes in
a cursor-key/function-key/mouse-event sequence.
 
> Or rather, no, don't bother, because even there might be problem in how
> we process the input escape sequences, these are unrelated to the
> display glitches we see.  So let's focus on the display glitches.

You could cut the discussion short by making the check that I suggested:
logging the decoded character/special-key values to look for instances
where the decoding returns individual bytes.

-- 
Thomas E. Dickey <[email-masked]>
http://invisible-island.net
ftp://invisible-island.net