bug#5650: 23.1; ERC causes Emacs to hang on network dropouts

[Richard Lewis]

When my network connection drops out, ERC loses its connection and
attempts to reconnect. I see the message "connecting to server
irc.freenode.net 6777..." in the minibuffer and Emacs becomes
unresponsive.

netstat tells me that the Emacs process has a TCP socket in the
SYN_SENT state to freenode.net.

I found today that, if left for a long time (not sure how long, but <
2 hours [which was the amount of time I left my computer unattended]
and > ~10 minutes [which was the amount of time I fiddled with it last
time it happened]), it evetually gives up and Emacs becomes responsive
again.

In GNU Emacs 23.1.1 (i486-pc-linux-gnu, GTK+ Version 2.18.2)
 of 2010-01-27 on raven, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.10705000
configured using `configure  '--build=i486-linux-gnu' '--host=i486-linux-gnu' 
'--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' 
'--localstatedir=/var/lib' '--infodir=/usr/share/info' 
'--mandir=/usr/share/man' '--with-pop=yes' 
'--enable-locallisppath=/etc/emacs23:/etc/emacs:/usr/local/share/emacs/23.1/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/23.1/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/23.1/leim'
 '--with-x=yes' '--with-x-toolkit=gtk' '--with-toolkit-scroll-bars' 
'build_alias=i486-linux-gnu' 'host_alias=i486-linux-gnu' 'CFLAGS=-DDEBIAN -g 
-O2' 'LDFLAGS=-g' 'CPPFLAGS=''

Important settings:
  value of $LC_ALL: en_GB.UTF-8
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: en_GB.UTF-8
  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: Org

Minor modes in effect:
  erc-list-mode: t
  erc-menu-mode: t
  erc-autojoin-mode: t
  erc-ring-mode: t
  erc-networks-mode: t
  erc-pcomplete-mode: t
  erc-track-mode: t
  erc-track-minor-mode: t
  erc-match-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-netsplit-mode: t
  diff-auto-refine-mode: t
  display-time-mode: t
  display-battery-mode: t
  jabber-activity-mode: t
  jabber-mode-line-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  show-paren-mode: t
  delete-selection-mode: t
  iswitchb-mode: t
  shell-dirtrack-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-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

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