screen -d

Does not start screen, but detaches the elsewhere running screen session

Subcommands

Name	Description
`-r`	Reattach a session and if necessary detach it first
`-R`	Reattach a session and if necessary detach or even create it first
`-RR`	Reattach a session and if necessary detach or create it. Use the first session if more than one session is available