Recreate TMUX session files after tmp cleanup

 Tmux stores information related to all sessions in /tmp/ . If these files get deleted, tmux will not be able to list or attach to sessions but tmux sessions are not terminated. Tmux sessions keeps running in a process.

To recreate these session files we need to send SIGUSR1 signal to tmux server process. 

for that ps aux|grep tmux  will give the process id for tmux server.

kill -10 <PID>

will send SIGUSR1 signal to tmux server process.

now you can use tmux ls and tmux a to attach to see list of  running sessions and attach to sessions.