Updating tmux without killing active sessions

I've been using tmux for a while, and even though I didn't like it at first, now I'm in love with it. I'm mostly using it as a GNU Screen alternative, but I don't use some of its fancy features like tabs, mainly because my window manager takes care of multiple terminal windows for me.

After a while, I got bored of starting a tmux session and configuring it every time, so I decided to give tmuxinator a try. The tmuxinator docs clearly stated that tmux >= 1.8 was needed, but I was using tmux version 1.6. I downloaded the latest stable tmux version from upstream, compiled it, installed it and tried to run it. I was greeted with this message:

    protocol version mismatch (client 8, server 6)

What happened is that I had some tmux sessions still running using the 1.6 version. The obvious, and only, solution that came to my mind was to kill all running tmux sessions. Problem was, one of those sessions had my Irssi stuff open and, since I have yet to properly setup an irssi config file, I would have to reconnect to all servers, re-authenticate, rejoin all open channels, etc. Ain't nobody got time for that.

Enter reptyr. Copying reptyr's description:

    reptyr is a utility for taking an existing running program and
    attaching it to a new terminal. Started a long-running process
    over ssh, but have to leave and don't want to interrupt it? Just
    start a screen, use reptyr to grab it, and then kill the ssh
    session and head on home.

So, all I had to do was open a screen, detach the irssi processes from tmux, reattach them to screen using reptyr, kill all running tmux processes, restart the tmux server and, finally, reattach the irssi processes to tmux. Much to my surprise, it worked out flawlessly.

Now all that's left, is to populate my ~/.tmuxinator config files and push them to my dotfiles.