fix tmux auto-attach spawning nested clients and blocking detach

Two problems made the auto-attach loop:

$TMUX was the only nesting guard, and it is trivially lost - sudo -i,
env -i, ssh, and dropbear all hand back an interactive tty shell with it
unset, so a shell below tmux would start another tmux. The guard also
never checked for a login shell, so anything spawning `$SHELL -i`
(fzf-tmux, file-manager shell escapes, editor :sh) dragged in a whole
tmux client and a fresh grouped session. Now guarded on a login shell
with stdin and stdout both a terminal, a $TERM that can host tmux, and
an exported $TMUX_AUTOSTART that survives into panes and into nested
shells that strip $TMUX.

detach-on-destroy was off while the per-client sessions set
destroy-unattached on. Those fight: detaching destroys the session, and
off means the client is then switched to the most recently active
remaining session instead of being allowed to leave - so detach put you
back into "main". Restored to on, which is also the default.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This commit is contained in:
daniel fusser
2026-09-13 00:28:36 +02:00
committed by dafu
co-authored by Claude Opus 5
parent 0a4166189f
commit 67e6d4ba4d
2 changed files with 17 additions and 2 deletions
+13 -1
View File
@@ -220,8 +220,20 @@ PS4='[$EPOCHREALTIME] '; PS1='#'; (( USER_ID )) && PS1='→'; PS1=$'\001\r''${|
# grants each connection its own session grouped with "main" (shared panes,
# independent window navigation). No -exec, so if tmux is missing or
# exits/crashes for any reason, this shell just continues normally.
#
# Guards, in order: interactive; stdin and stdout are both a terminal; not
# already inside tmux; not below a tmux we started ($TMUX_AUTOSTART survives
# into panes and into nested shells that strip $TMUX, e.g. sudo -i, env -i,
# ssh, dropbear); login shell only, so tools that spawn `$SHELL -i` (fzf-tmux,
# file-manager shell escapes, editor :sh) don't drag in a whole tmux client;
# terminal can actually host tmux; tmux is installed.
tmuxbin=$(\\builtin whence -p tmux 2>/dev/null)
if [[ $- = *i* ]] && [[ -t 0 ]] && [[ -z $TMUX ]] && [[ -n $tmuxbin ]]; then
if [[ $- = *i* ]] && [[ -t 0 ]] && [[ -t 1 ]] \
&& [[ -z $TMUX ]] && [[ -z $TMUX_AUTOSTART ]] \
&& [[ $0 = -* ]] \
&& [[ $TERM != dumb && $TERM != linux ]] \
&& [[ -n $tmuxbin ]]; then
\\builtin export TMUX_AUTOSTART=1
"$tmuxbin"
fi
unset tmuxbin