23.0.50; Tramp blocks Emacs when unconnected to server

["Martin Lüthi" <luethi@vaw.baug.ethz.ch>]

Hi

A major annoyance of Tramp is that it blocks Emacs when the server is
not reachable. The symptoms are

o open file on remote host with Tramp, edit, save
o disconnect from network (like: get laptop sleeping, reconnect
  somewhere else)
o close buffer visiting the remote file

The last action (closing the buffer) is not possible, and Emacs blocks
for a long time. C-g stops the unsuccessful communication
attempt. However it should be possible to close the buffer without
interaction with the remote server.


In GNU Emacs 23.0.50.1 (i686-pc-linux-gnu, GTK+ Version 2.11.6)
 of 2007-09-16 on yak
Windowing system distributor `The X.Org Foundation', version 11.0.10300000
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: en_US
  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.iso-8859-1
  locale-coding-system: iso-8859-1
  default-enable-multibyte-characters: t

Major mode: Text

Minor modes in effect:
  shell-dirtrack-mode: t
  which-function-mode: t
  show-paren-mode: t
  display-time-mode: t
  display-battery-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
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent input:
M-x v m <return> g q M-x m e n u <tab> b <tab> m <tab> 
<return> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <menu-bar> <help-menu> <report-emacs-b
ug>

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