Subject: [PATCH] Socket forwarding in emacsclient --tramp-prefix example
From: Peter Oliver <[email-masked]>
To: [email-masked]
Cc: Peter Oliver <[email-masked]>
Date: Sat, 21 Oct 2023 16:01:27 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Previously, the emacsclient --tramp-prefix documentation suggested
using it in conjunction with a forwarded TCP port.  However, OpenSSH
has supported forwarding sockets since version 6.7 (released 2014), so
let’s suggest that instead.  Sockets require less manual configuration
than ports, are less likely to clash, and are more secure, so will be
a better choice for the majority of people looking to set up this
facility for the first time.

* doc/emacs/misc.texi (emacsclient Options): Suggest forwarding sockets.
---
 doc/emacs/misc.texi | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/doc/emacs/misc.texi b/doc/emacs/misc.texi
index a05b7f6c6ea..93771832ff5 100644
--- a/doc/emacs/misc.texi
+++ b/doc/emacs/misc.texi
@@ -2158,8 +2158,9 @@ emacsclient Options
 Set the prefix to add to filenames for Emacs to locate files on remote
 machines (@pxref{Remote Files}) using TRAMP (@pxref{Top, The Tramp
 Manual,, tramp, The Tramp Manual}).  This is mostly useful in
-combination with using the Emacs server over TCP (@pxref{TCP Emacs
-server}).  By ssh-forwarding the listening port and making the
+combination with using the Emacs server from a remote host.  By
+ssh-forwarding the listening socket, or ssh-forwarding the listening
+port @pxref{TCP Emacs server} and making the
 @var{server-file} available on a remote machine, programs on the
 remote machine can use @command{emacsclient} as the value for the
 @env{EDITOR} and similar environment variables, but instead of talking
@@ -2171,16 +2172,13 @@ emacsclient Options
 effect as using the @samp{-T} option.  If both are specified, the
 command-line option takes precedence.
 
-For example, assume two hosts, @samp{local} and @samp{remote}, and
-that the local Emacs listens on tcp port 12345.  Assume further that
-@file{/home} is on a shared file system, so that the server file
-@file{~/.emacs.d/server/server} is readable on both hosts.
+For example, assume two hosts, @samp{local} and @samp{remote}.
 
 @example
-local$ ssh -R12345:localhost:12345 remote
-remote$ export EDITOR="emacsclient \
-        --server-file=server \
-        --tramp=/ssh:remote:"
+local$ ssh -R "/tmp/emacs-%r.socket":"$@{XDG_RUNTIME_DIR:-$@{TMPDIR:-/tmp@}/emacs%i@}$@{XDG_RUNTIME_DIR:+/emacs@}/server" remote
+remote$ export EMACS_SOCKET_NAME=/tmp/emacs-$USER.socket
+remote$ export EMACSCLIENT_TRAMP=/ssh:remote:
+remote$ export EDITOR=emacsclient
 remote$ $EDITOR /tmp/foo.txt #Should open in local emacs.
 @end example
 
-- 
2.41.0