In-between tmux and nothing, there is abduco(1): only attach/detach features.
One could set some $ABDUCO to the session name, and if not set, attach to
latest abduco session.
Here is what I currently use [2]:
if [ "$ABDUCO" ]; then
printf 'session already active: %s\n' "$ABDUCO"
exit 1
fi
name="$(abduco | tail -n +2 | iomenu -l 10 | sed -r 's/[^\t]*\t[^\t]*\t//')"
printf '\033[H\033[J'
[ "$SSH_CLIENT" ] && detach_key='^\' || detach_key='^Z'
[ "$name" ] && ABDUCO="$name" exec abduco -e "$detach_key" -A "$name" "$SHELL"
iomenu [3] is dmenu for the terminal (yet another).
[1]: https://github.com/martanne/abduco
[2]: https://github.com/josuah/etc/raw/master/bin/io-abduco
[3]: https://github.com/josuah/iomenu
