Subject: bug#32922: Echo area flickers when receiving data in network process

From: Eli Zaretskii <[email-masked]>
Date: Wed, 03 Oct 2018 21:49:56 +0300

> From: Mitchell Plamann <[email-masked]>
> Date: Wed, 3 Oct 2018 13:57:15 -0400
> 
> Steps to reproduce:
>   - Open "emacs -Q"
>   - Eval (make-network-process :name "foo" :server t :service 8080 :family 'ipv4)
>   - Press "C-x 5". After a few seconds, the echo area will display "C-x 5-".
>   - In another terminal, run "yes | nc localhost 8080"
>   - The "5-" in the echo area will begin to flicker.
> 
> I've tested this in emacs 25.3 and 26.1.
> 
> As far as I've been able to tell, the data coming in to the network process triggers [read_key_sequence] in
> [keyboard.c] to replay the "C-x 5" sequence. As part of this replay, it outputs "C-x", then "C-x 5", then "C-x 5-"
> to the echo area, which causes the "5-" to look like it is flickering.

This is deliberate, the code is explicitly written to replay the key
sequence.  For more about this, see

  http://lists.gnu.org/archive/html/emacs-devel/2018-09/msg00906.html