screen detach from session code example

Example 1: create a screen command

screen -S screen_name

Example 2: screen reattach to session

> Starting Named Session
$ screen -S session_name

> Find the session ID list 
$ screen -ls

> Restore screen or connect to existing session
$ screen -r session_nameORsession_ID

> I'm in a screen session? Which one?
	> I am in screen
$ echo $STY 
29624.pts-1.iain-10-04
$
	> I am not in screen
$ echo $STY

$