You can run something like this to prompt for the root password, and then launch a detached screen session with the command start_game_server executed within:
Code:
gksu -u root 'screen -S gameOn -md start_game_server'&
To turn on multiuser mode, you can either do this in a screenrc config file (before launch), or you can send the command externally this way, after it has been started:
as root:
Code:
screen -X multiuser on
as user who needs to login as root:
Code:
gksu -u root 'screen -X multiuser on'
Root can add users like this:
Code:
screen -X addacl bob
screen -X aclchg bob -w 0
screen -X addacl mindy
screen -X aclchg mindy -w 0
screen -X addacl peter
screen -X aclchg peter -w 0
That should give user visibility to the window, but no obvious way of executing a command as root. The user list can also be configured in the screenrc config file.