Let's see if anyone screams about not being able to specify $TMPDIR for their tmux sockets.
Let's see if anyone screams about not being able to specify $TMPDIR
for their tmux sockets.

(Over the years, I have seen $TMPDIR set up worse than /tmp many times,
and don't know how this practice infected other parts of the system.
Nothing uses tmpdir(3), nor a huge-temporary-file program like sort.)
ok nicm

klaxalk/tmux,klaxalk/tmux,klaxalk/tmux,klaxalk/tmux,klaxalk/tmux