bug#33934: 26.1; server.el/emacsclient mismatch regarding socket...

[Eli Zaretskii <eliz@gnu.org>]

> From: kris <cq.personal@gmail.com>
> Date: Mon, 31 Dec 2018 03:02:22 +0100
> 
> emacsclient has the -s option for specifying a UNIX socket directory
> (emacslient -h says filename but it is a directory in the code - the bug
> report!).
> but server.el uses defvar to set server-socket-dir and there appears no
> way to override it.
> 
> I changed defvar to defcustom to continue.
> this is useful for my use case of running separate emacs
> processes per project directory in order to do file change monitoring
> with emacsclient -e signalling the correct session.

Can you explain how you arrived at the conclusion that -s names the
directory of the socket file?

My reading of the code is that it's indeed the name of the socket
file, either with or without the leading directories.  In the former
case, the file is placed under a user-specific subdirectory of
$TMPDIR; in the latter case, the file is placed where the leading
directories specify.  And the user option server-name in Emacs, which
_is_ a defcustom, causes the server to do the same, depending on
whether server-name includes leading directories.

So it sounds to me like you could use a different server-name and
argument to -s for each project, and get what you want without any
changes, without ever needing to modify socket-dir.  If I'm missing
something, please point out what did I miss.

Thanks.