bug#5803: 23.1.94; Using tq-enqueue in timer messes with keystroke echoing

[David Engster <deng@randomsample.de>]

This bug report will be sent to the Free Software Foundation,
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Please write in English if possible, because the Emacs maintainers
usually do not have translators to read other languages for them.

Your bug report will be posted to the bug-gnu-emacs@gnu.org mailing list,
and to the gnu.emacs.bug news group.

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug.  If you can, give
a recipe starting from `emacs -Q':

When using `tq-enqueue' in a timer, the keystroke echoing in the
echo area becomes weird or is completely invisible.  You should be able
to reproduce this as follows:

* emacs -Q

* Evaluate the following:

(setq proc (start-process "shell" (get-buffer-create "*process*") "/bin/sh"))
(setq mytq (tq-create proc))
(defun send-test ()
  (tq-enqueue mytq "echo TEST\n" "TEST[^0]*" nil nil))
(setq timer (run-with-timer 1 1 'send-test))

* Now hit 'C-x' and wait a second.

* The string "C-x-" should appear in the echo area, but nothing can be
  seen.

* Hit "C-g". (The message "C-x C-g is undefined" appears, which is
  expected.)

* Now evaluate

(cancel-timer timer)
(setq timer (run-with-timer 1 2 'send-test))

* Wait a few seconds, now again hit "C-x" and watch the echo area.

* In seemingly random succession, the strings "C-x", " C-x" and the
  empty string appear, with a few seconds time in between.

* Evaluating (cancel-timer timer) will restore normal behavior.


If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
/opt/emacs/share/emacs/23.1.94/etc/DEBUG.


In GNU Emacs 23.1.94.1 (i686-pc-linux-gnu, GTK+ Version 2.18.3)
 of 2010-03-30 on void
Windowing system distributor `The X.Org Foundation', version 11.0.10604000
configured using `configure  '--prefix=/opt/emacs''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Emacs-Lisp

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x v e r s i o n <return> C-x C-f [ r p c y <backspace> 
<backspace> <backspace> <backspace> <backspace> p r 
o c <tab> <return> <down> <down> <down> <down> <down> 
<down> C-k C-k <down> <down> <down> <up> <up> <down> 
<down> <down> <down> <right> <right> <left> <left> 
<up> <up> <up> <up> <up> <left> C-x C-e <down> C-x 
C-e <down> <down> C-e C-x C-e <down> C-x C-e <down> 
C-e C-x C-g <down> <up> C-x C-e <down> <down> C-x C-g 
<up> <up> <up> <down> <down> <down> <left> C-x C-e 
<up> <up> <down> <right> <right> <right> <right> <right> 
<right> <right> <right> <right> <backspace> 2 C-e C-x 
C-e <down> <down> C-x <left> C-x C-x b C-x b <left> 
<return> <left> C-x C-e <up> <up> <down> <right> <right> 
<right> <right> <right> <right> <right> <right> <right> 
<backspace> 3 C-e C-x C-e <down> C-x C-g M-x r e p 
o <tab> r <tab> <return>

Recent messages:
(nil #<process shell> . #<buffer  tq-temp-shell>)
send-test
nil
[nil 19377 10445 698196 1 send-test nil nil]
nil
[nil 19377 10458 258144 2 send-test nil nil]
exchange-point-and-mark: No mark set in this buffer
nil
[nil 19377 10482 122182 3 send-test nil nil]
Making completion list...

Load-path shadows:
None found.

Features:
(shadow sort mail-extr message sendmail regexp-opt ecomplete rfc822 mml
mml-sec password-cache mm-decode mm-bodies mm-encode mailcap mail-parse
rfc2231 rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader gnus-util
netrc time-date mm-util mail-prsvr gmm-utils wid-edit mailheader canlock
sha1 hex-util hashcash mail-utils emacsbug help-mode easymenu view tq
tooltip ediff-hook vc-hooks lisp-float-type mwheel x-win x-dnd
font-setting tool-bar dnd fontset image fringe lisp-mode register page
menu-bar rfn-eshadow timer select scroll-bar mldrag mouse jit-lock
font-lock syntax facemenu font-core frame cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese hebrew
greek romanian slovak czech european ethiopic indian cyrillic chinese
case-table epa-hook jka-cmpr-hook help simple abbrev loaddefs button
minibuffer faces cus-face files text-properties overlay md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process dbusbind system-font-setting
font-render-setting gtk x-toolkit x multi-tty emacs)