emacsclient: prefer XDG_RUNTIME_DIR (Bug#33367)

* lib-src/emacsclient.c: Disable -Wformat-truncation=2,
to avoid false alarms about the new snprintf calls.
(local_sockname): New function.
(set_local_socket): Use it.  Prefer XDG_RUNTIME_DIR (if set)
for location of socket directory.  Avoid unnecessary memory
allocation by using snprintf to destination.
* lisp/server.el (server-socket-dir): Prefer XDG_RUNTIME_DIR if set.

1 files changed, 5 insertions, 1 deletions

diff --git a/admin/notes/multi-tty b/admin/notes/multi-tty
index 5b34bb598ef..619af8e7fab 100644
--- a/admin/notes/multi-tty
+++ b/admin/notes/multi-tty
@@ -171,7 +171,11 @@ preload-emacs "$name" wait
 name="$1"
 waitp="$2"
 screendir="/var/run/screen/S-$USER"
-serverdir="/tmp/emacs$UID"
+if [ "${XDG_RUNTIME_DIR+set}" ]; then
+  serverdir="$XDG_RUNTIME_DIR/emacs"
+else
+  serverdir="${TMPDIR-/tmp}/emacs$UID"
+fi
 emacs=/usr/bin/emacs-multi-tty # Or wherever you installed your multi-tty Emacs
 
 if [ -z "$name" ]; then