Emacs "property-notify event" timeouts on RealVNC 4.X vncconfig

[Andrew M. Scott]

This bug report will be sent to the Free Software Foundation,

PROBLEM:

Seeing Emacs "Timed out waiting for property-notify event" when using RealVNC's
vncconfig 4.X (helper app like KDE klipper) when a large portion of text is 
killed. 

My personal experience is "large" seems to be (ascii) files > 2.5MB
using vncconfig 4.1.1 or vncconfig Enterprise 4.1.7 and independent of
(setq x-select-enable-clipboard t) or (setq x-select-enable-clipboard
nil)

I am using the fvwm v2.4.19 window manager not KDE, nor klipper.

These symptoms appear to be similar to the Emacs etc/PROBLEMS entry:

 * Emacs hangs on KDE when a large portion of text is killed.
 This is caused by a bug in the KDE applet `klipper' which periodically
 requests the X clipboard contents from applications.  Early versions
 of klipper don't implement the ICCM protocol for large selections,
 which leads to Emacs being flooded with selection requests.  After a
 while, Emacs will print a message:

     Timed out waiting for property-notify event

 A workaround is to not use `klipper'.

REMEDIES:

    1. I'll file a bug with RealVNC.com against vncconfig 4.X for this
       issue, which may or may not be the same "ICCM protocol for large
       selections" mentioned in Emacs' etc/PROBLEMS.

    2. Killing vncconfig 4.X isn't really a solution to my general need for
       cut/paste support between apps within/between VNC sessions and/or
       Microsoft Windows apps. 

=>  3. Is there a way that GNU Emacs can be made more "tolerant" of the 
       "Emacs being flooded with selection requests" issue mentioned in
       etc/PROBLEMS for klipper? 

HOW TO REPRODUCE:

1.  With vncconfig running:

% vncconfig &
% emacs -q &

M-x shell RET yes RET ; (wait for a few 100,000 lines)
C-c C-c 
C-x h   <i.e. mark-whole-buffer>
M-w     <i.e. kill-ring-save>

=> Debugger entered--Lisp error: (error "Timed out waiting for property-notify 
event")

My experience across various scenarios is that after seeing this
property-notify error that Emacs either appears to be hung or just starts
acting erratically, at which point I kill Emacs and restart it.

2. With vncconfig *not* running, e.g. 
   % kill -9 <the vncconfig process #> 

% emacs -q &

M-x shell RET yes RET ; (wait for a few 100,000 lines)
C-c C-c 
C-x h   <i.e. mark-whole-buffer>
M-w     <i.e. kill-ring-save>

Cut and paste operates normally.

In GNU Emacs 22.0.50.1 (x86_64-unknown-linux-gnu, X toolkit)
 of 2005-10-31 on chlr5836
X server distributor `The XFree86 Project, Inc', version 11.0.40201000
configured using `configure '--prefix=/stor/garray/linux_2.6.5_x86-64' 
'--x-includes=/usr/intel/pkgs/X11/R6.7.0-64/include' 
'--x-libraries=/usr/intel/pkgs/X11/R6.7.0-64/lib' 'CC=gcc' 'CFLAGS=-O2 
-I/usr/intel/pkgs/X11/R6.7.0-64/include -L/usr/intel/pkgs/X11/R6.7.0-64/lib 
-I/usr/intel/pkgs/zlib/1.2.1-64/include -L/usr/intel/pkgs/zlib/1.2.1-64/lib  
-I/usr/intel/pkgs/ncurses/5.4/include -L/usr/intel/pkgs/ncurses/5.4/lib 
-I/usr/intel/pkgs/libungif/4.1.3/include -L/usr/intel/pkgs/libungif/4.1.3/lib 
-I/usr/intel/pkgs/libpng/1.0.16rc1-64/include 
-L/usr/intel/pkgs/libpng/1.0.16rc1-64/lib -I/usr/intel/pkgs/jpeg/6b-64/include 
-L/usr/intel/pkgs/jpeg/6b-64/lib' 'LDFLAGS=-L/usr/intel/pkgs/X11/R6.7.0-64/lib 
-L/usr/intel/pkgs/zlib/1.2.1-64/lib -L/usr/intel/pkgs/ncurses/5.4/lib 
-L/usr/intel/pkgs/libungif/4.1.3/lib -L/usr/intel/pkgs/libpng/1.0.16rc1-64/lib 
-L/usr/intel/pkgs/jpeg/6b-64/lib 
-Wl,-rpath=/usr/intel/pkgs/X11/R6.7.0-64/lib:/usr/intel/pkgs/zlib/1.2.1-64/lib:/usr/intel/pkgs/ncurses/5.!
 
4/lib:/usr/intel/pkgs/libungif/4.1.3/lib:/usr/intel/pkgs/libpng/1.0.16rc1-64/lib:/usr/intel/pkgs/jpeg/6b-64/lib''

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
  locale-coding-system: utf-8
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  auto-compression-mode: t
  tool-bar-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  line-number-mode: t

Recent input:
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <menu-bar> <help-menu> <report-emacs-b
ug>

Recent messages:
(emacs -q)
Loading disp-table...done
For information about the GNU Project and its goals, type C-h C-p.
Loading emacsbug...done