bug#4064: 23.1; Hang up from tty mode when X server goes away

[Dickon Reed (dreed)]

I am running my own build of emacs 23.1.1 on CentOS 4.4. I start emacs
under screen and run server-start from my init file. I then login via
ssh (PuTTy) from an Windows XP box, connect to the screen session, and
use make-frame-on-display to open a frame on a Cygwin/X version 1.5.3
(20090222) X server running on my desktop Windows XP box. So far,
everything works fine. After a few hours work, I hibernate my Windows
box, and then log in via ssh from a different site. I find the emacs
running screen unresponsive, whereas I'd have liked the emacs
session under screen to be working.

Later, I woke up the Windows box, logged back into the screen session
and found it had recently reported that it had lost the connection to
the X server (see log below). At that point, I can only a frame again
and everything is back to normal.




In GNU Emacs 23.1.1 (i686-pc-linux-gnu, X toolkit)
 of 2009-07-30 on runbench-dev.uk.level5networks.com
configured using `configure  '--with-gif=no''

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_GB.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:
  diff-auto-refine-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
e SPC t h e SPC r e s u l t s SPC s t o r e SPC w a 
s SPC b r o k e n " <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> c <backspace> c 
a l l b a c k s SPC a n d <backspace> <backspace> <backspace> 
o r SPC f i l e s SPC a r e SPC n o t SPC w o r k i 
n g " <return> h g SPC q p o p <return> h g SPC q <backspace> 
p u l l SPC - u <return> h g SPC q p u s h SPC - a 
<return> h g SPC q a p <return> q <backspace> h g SPC 
q f i n SPC - a <return> h g SPC q a d d <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> h g SPC q p a <backspace> 
<backspace> a p SPC - s <return> h g SPC q p o p SPC 
- a <return> h g SPC q p u s h SPC - a <return> h g 
SPC <backspace> <backspace> <backspace> <backspace> 
<backspace> h g SPC t i p <return> h g SPC p u s h 
<return> <switch-frame> C-x n <switch-frame> ESC [ 
1 5 ~ ESC O A ESC O B ESC O B C-x C-f ~ / . e m a c 
s RET C-x o C-x 0 C-s f 7 C-s ESC O A ESC O B ESC O 
B ESC O B ESC O B ESC O B ESC O B ESC O B ESC O B ESC 
O A C-s d r C-x o ESC x r e p o r t - e m TAB RET

Recent messages:
Wrote /local/dr/runbench/nagbench.py
Mark saved where search started [3 times]
Saving file /local/dr/runbench/nagbench.py...
Wrote /local/dr/runbench/nagbench.py
(No files need saving)
Compilation finished
Quit
call-interactively: Text is read-only [4 times]
Connection lost to X server `dr-desktop:0.0'
Mark saved where search started [2 times]