bug#9617: 23.1; Tramp blocks other Emacs use while waiting

[Michael Hoffman <gnu-hoffman@sneakemail.com>]

There are sometimes unavoidable delays in using Tramp to access remote
files. It would be very useful if it were possible to load or save a
buffer using Tramp in a non-blocking way so that use of Emacs on other
buffers could continue.

In GNU Emacs 23.1.3 (x86_64-unknown-linux-gnu, GTK+ Version 2.10.4)
 of 2009-08-20 on rhel5-x64.grid.gs.washington.edu
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
configured using `configure  '--prefix=/net/gs/vol3/software/modules-sw/emacs/23.1/Linux/RHEL5/x86_64' '--with-x' '--with-gif=no''

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.UTF-8
  value of $XMODIFIERS: @im=SCIM
  locale-coding-system: iso-latin-1-unix
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  hi-lock-mode: t
  eldoc-mode: t
  yas/global-mode: t
  yas/minor-mode: t
  shell-dirtrack-mode: t
  iswitchb-mode: t
  show-paren-mode: t
  savehist-mode: t
  global-auto-revert-mode: t
  display-time-mode: t
  auto-insert-mode: t
  recentf-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
  blink-cursor-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 messages:
Loading savehist...done
Loading paren...done
Loading winner...done
Loading /net/noble/vol2/home/mmh1/.recentf...done
Loading ~/etc/emacs/custom-settings...done
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