bug#3521: 23.0.94; process-send-region errors / bug#2272 strikes again

[Tassilo Horn]

Tassilo Horn <thorn@fastmail.fm> writes:

>> Therefore, use this recipe to reproduce the bug:
>>
>> * emacs -Q
>> * M-x display-time RET
>> * Evaluate the code Tassilo posted
>> * The error will appear at the next full minute.
>>
>> Tassilo, if you do not have (display-time) in your .emacs, look for
>> other stuff that could update the modeline in the background.
>
> I don't use it, but for example rcirc-track-minor-mode updates the
> mode-line whenever someone talks in an IRC channel I'm visiting.  This
> happens quite ofter (< 1 min).

It seems not every update of the mode line triggers the error, but this
snippet errors after about 5-10 seconds here (with emacs -Q):

--8<---------------cut here---------------start------------->8---
(progn
  (run-with-timer 1 1 'force-mode-line-update)
  (setq proctest
        (start-process "cat" (get-buffer-create "cat") "/bin/cat"))
  (with-temp-buffer
    (dotimes (dummy 999999)
      (insert
       (concat (number-to-string (random))
               (number-to-string (random))
               (number-to-string (random))
               (number-to-string (random))
               "\n")))
    (process-send-region proctest (point-min) (point-max)))
  (delete-process proctest))
--8<---------------cut here---------------end--------------->8---

Bye,
Tassilo