Add 'Reconnect to broken tmux session' article as draft

content/blog/2020-05-13_reconnect-to-broken-tmux-session/index.md

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+title = "Reconnect to broken tmux session"
+description = "Reconnect to a running tmux session, that tmux fails to connect to."
+
+# TODO: remove to release
+draft = true
+
+[taxonomies]
+categories = ["guide", "blog"]
+tags = ["tmux"]
+
+[extra]
+comments = true
+zenn_applause = true
++++
+
+Ever tried to attach to a running tmux session, only to find that that fails?
+
+```bash
+tmux attach
+# no sessions
+tmux ls
+# error connecting to /tmp/tmux-1000/default (No such file or directory)
+```
+
+Even though you're sure tmux is running fine, it shows up as running in your
+task manager after all.
+
+_So, where are your precious tmux sessions?_
+
+<!-- more -->
+
+## Socket file
+All your tmux sessions are hosted by a single tmux process. This is persistent
+and keeps running until you quit all sessions again.
+
+The process creates a socket file, other processes use this to talk to it. When
+you invoke `tmux attach`, the program finds this socket, and attaches to session
+through the socket.
+
+Now what happens when you delete this file? Exactly, your `tmux` command doesn't
+know how to connect to the running server. That's what we're seeing here.
+
+## Recreate socket
+Because others had the same issue, tmux provides a feature to fix this. When you
+send the `SIGUSR1` signal to the host process, it creates a fresh socket file
+for you.
+
+For this you need to find the PID of the running tmux server. Find it through
+your task manager, or invoke the following command to list all running tmux
+programs. The first line is probably your server, the first number on that line
+is the PID you'll need:
+
+```bash
+ps kstart_time -ef | grep tmux
+# timvisee    5612    2344  0 may11 ?        Ss    16:22 tmux new
+# timvisee  913216  911044  0 21:22 pts/5    S+     0:00 grep tmux
+```
+
+For me it was `5612`, so I invoke the following and attach again (be sure to use
+your own PID):
+
+```bash
+sudo kill -SIGUSR1 5612
+tmux attach
+```
+
+Happy hacking!