Being a regular tmux user. Migrating a running process into tmux using reptyr comes handy.
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.
The package available in Fedora/Ubuntu repositories.
% sudo yum install -y reptyr # For Fedora users % sudo apt-get install -y reptyr # For Ubuntu users
The steps to migrate a process is
- Sending the current foreground job to the background using CTRL-Z.
- List all the background jobs using jobs -l. This will get you the PID
% jobs -l  + 16189 suspended vim foobar.rst
Here the PID is 16189
- Start a new tmux or screen session. I will be using tmux
- Reattach the background process using
% reptyr 16189
If this error appears
Unable to attach to pid 16189: Operation not permitted The kernel denied permission while attaching
Then type in the following command as root.
% echo 0 > /proc/sys/kernel/yama/ptrace_scope
These are commands are also compatible with screen.