Linux Trick 3: Collaboration with screen

Now, let's think about the following situation:

David, the high-maintenance user from product engineering, calls: "I need you to help me understand why I can't compile supercode.c on these new machines you deployed."
"Fine," you say. "What machine are you on?"
David responds: " Porsche." OK, you say. You exercise your godlike root powers and on another machine become David:

# su - david
 
Then you go over to posh:

# ssh porsche
 
Once you are there, you run:

# screen -S foo
 
Then you holler at David:

"Hey David, run the following command on your terminal: # screen -x foo."

This will cause your and David's sessions to be joined together in the holy Linux shell. You can type or he can type, but you'll both see what the other is doing. This saves you from walking to the other floor and lets you both have equal control. The benefit is that David can watch your troubleshooting skills and see exactly how you solve problems.


At last you both see what the problem is: David's compile script hard-coded an old directory that does not exist on this new server. You mount it, recompile, solve the problem, and David goes back to work. You then go back to whatever lazy activity you were doing before.


The one caveat to this trick is that you both need to be logged in as the same user. Other cool things you can do with the screen command include having multiple windows and split screens. Read the man pages for more on that.

But I'll give you one last tip while you're in your screen session. To detach from it and leave it open, type: Ctrl-A D. (I mean, hold down the Ctrl key and strike the A key. Then push the D key.)
You can then reattach by running the screen -x foo command again.