Command Options Command Description screen Start a new session screen -S <name> Start a new session with a session name screen -ls List running sessions screen -r [name] Reattach to a running session screen -X Send a command to a running session screen -X -S <name> Send a command to a specified session screen -X -S <name> kill Kill a running session Command Key in Sessions By default, Ctrl-a is a special key to send a command to a screen’s session.