Linux Desktop Hacks

Stop Using Terminal Command-Line Switches #50

Chapter 7, Terminal Empowerment

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HACK

Now you are sharing your screen session; go ahead, try it from multiple

shells. You can attach as many sessions as you want, but when you exit the

application (assuming you launched the application directly like you did for

irssi, not from a screen shell), that screen terminates.

It’s Good to Share

It is also possible for multiple users to access a single screen instance—e.g.,

to collaborate on a document or some code. For this to work, the following

must apply:

• screen must be compiled with “multiuser” enabled (most packages are).

• screen must be suid root (

chmod +s /usr/bin/screen).

To do this as

user1 and assuming screen is running, press Ctrl-A and then

type

:multiuser on. Still as user1, press Ctrl-A and then type :acladd

username

, where username is the user you want to be able to access your

screen. For this example, use

user2.

As

user2, launch screen with:

foo@bar:~$ screen -x user1/

At this point you should be connected to user1’s screen. Besides acladd, you

also have the

aclchg, acldel, and aclgrp commands for controlling who can

access your screen, and what they can do (e.g., you can make them read-

only). To see who’s connected to your session press Ctrl-A. Then press the

asterisk (*) key.

To prevent people from (temporarily) editing all your windows, press Ctrl-A

and then type

:writelock on to lock editing