#!/bin/sh
#

for s in $(tmux list-sessions -F '#{session_name}'); do
    p=$(tmux list-panes -F '#{pane_tty}' -t "$s")
    if [ "$p" = "$(tty)" ]; then
        # Session already running
        exit 0
    fi
done

tmux attach-session -t default_ssh || tmux new-session -s default_ssh