Slackware Linux Essentials
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8.4 Virtual Terminals

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So you're in the middle of working on something and you decide you need to do -something else. You could just drop what you're doing and switch tasks, but this is a -multi-user system, right? And you can log in as many times simultaneously as you want, -right? So why should you have to do one thing at a time?

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You don't. We can't all have multiple keyboards, mice, and monitors for one machine; -chances are most of us don't want them. Clearly, hardware isn't the solution. That leaves -software, and Linux steps up on this one, providing “virtual terminals”, or -“VTs”.

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By pressing Alt and a function key, you can switch -between virtual terminals; each function key corresponds to one. Slackware has logins on -6 VTs by default. Alt+F2 will take you to the -second one, Alt+F3 to the third, etc.

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The rest of the function keys are reserved for X sessions. Each X session uses its own -VT, beginning with the seventh (Alt+F7) and -going up. When in X, the Alt+Function key -combination is replaced with Ctrl+Alt+Function; so if you are in X and want to get back to a text login -(without exiting your X session), Ctrl+Alt+F3 will take you to the third. (Alt+F7 will take you back, assuming you're using the first X session.)

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8.4.1 Screen

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But what about situations where there are no virtual terminals? What then? -Fortunately, slackware includes a beautiful screen manager aptly named screen. screen is a terminal emulator that -has virtual terminal like capabilities. Executing screen flashes -a brief introduction, then dumps to a terminal. Unlike the standard virtual terminals, -screen has its own commands. All screen -commands are prefixed with a Crtl+A -keystroke. For example, Ctrl+A+C will create a new terminal session. Ctrl+A+N will switch to the next terminal. Ctrl+A+P switches to the -previous terminal.

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screen also supports detaching and re-attaching to screen sessions which is particularly useful for remote sessions via -ssh and telnet, (more on those later). -Ctrl+A+D will detach -from the currently running screen. Executing screen -r will list -all currently running screen sessions you may reattach to.

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-% screen -r
-There are several suitable screens on:
-     1212.pts-1.redtail      (Detached)
-     1195.pts-1.redtail      (Detached)
-     1225.pts-1.redtail      (Detached)
-     17146.pts-1.sanctuary   (Dead ???)
-Remove dead screens with 'screen -wipe'.
-Type "screen [-d] -r [pid.]tty.host" to resume one of them. 
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Running screen -r 1212 would reattach to the first screen -listed. I mentioned earlier how useful this was for remote sessions. If I were to login -to a remote slackware server via ssh, and my connection was -severed by some chance occurrence such as a local power failure, whatever I was doing at -that moment would instantly perish, which can be a horrible thing for your server. Using -screen prevents this by detaching my session if my connection is -dropped. Once my connection is restored, I can reattach to my screen session and resume -right where I left off.

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