Sharing a screen session
screen first needs to be set SUID (this has security implications).
Now create the screen session as your desired user, and do:
- Ctrl+a, ":multiuser on", hit enter
- Ctrl+a, ":acladd $user" (where $user is the username to share with), hit enter
Another user can connect to the screen session with:
1 screen -x $session_name
Source: LinuxGazette: A 'revisited' guide to GNU Screen