Many long-time SSH users already know this, but I receive a number of emails from people who haven’t heard of the awesome utility that is GNU Screen. Screen has several benefits for frequent (and even infrequent) SSHers.
- Persistent logins: after setting up a Screen session, you can reconnect to it at any time. In practical terms this means that even when your crappy 3G coverage *cough AT&T cough* flakes out and you lose connection to your server, you don’t lose your work. You can reconnect and pick up right where you left off. To do this, just type this at the shell prompt:screen -RDaA
- Multiple shells within a single connection. Screen lets you create a virtually unlimited number of active sessions within one connection and switch between them. BBSSH shortcuts make this easy to manage.
- Scrollback buffer: while BBSSH’s scrollback support is improving with every release, using screen for scrolling doesn’t use extra memory on your device — so you can keep a scrollback buffer that is much larger. (Mine is 5000 lines). And those multiple sessions I mentioned above? Each one has its own scrollback buffer under screen. One thing to note is that BBSSH’s vertical scrollback buffer is of much less use if you are using screen – it’s pretty much either/or.
- BBSSH’s copy support is fairly rudimentary (though I hope to change this soon). While screen’s copy/paste won’t let you share with your BB device, it will let you easily copy and paste between mul
- For those of you looking forward to getting a new high-res BB OS7 devices (or who like the small font sizes BBSSH has available) screen allows you to split the window showing 2 or more sessions concurrently.
- IRC fan? Run screen and irssi together, and you have IRC from your BlackBerry device – except unlike most of the IRC clients available on BlackBerry, irssi is a powerful client that runs on your remote system and not your BB — so the connection remains stable.
Stay tuned and I’ll be posting some BBSSH macros and shortcut bindings I use with screen (and irssi) that make it sit up, beg and roll over with a single keystroke/touchscreen tap.
One important note: disable “visual bell” on screen in order to avoid a terminal bug in BBSSH. To do this, type: CTRL+A CTRL+G . You only need to do this once. (For folks with hardware keyboards using default bindings, that would be: SYM,A,SYM,G)
For now, here are some useful links:
- Screen Shortcuts Cheat Sheet (also available in other formats)
- irssi cheat sheet
- launching screen: startup options
