Frequently Asked Questions

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5. Usage hints

5.6: Why should I use the "screen" program?

If the remote server is operated by a UNIX operating system, it is very convenient to use the 'screen' program - a screen manager with VT100/ANSI terminal emulation. The advantage is that your GAP session will not be lost in case of (unintended) interrupts of your network connection, and that you can close the network connection while GAP is busy with long computations.

It is likely that screen is already installed on your server - just type 'screen' to check this. (Otherwise look here to get it, or on Linux install the 'screen' package from your distribution.) If so, it will be launched and you will see its welcome message. Now you are able to work just as usual, but in case of a broken connection your session will not be closed, and your computations will be continued while you are not connected. When you will connect to the server next time, enter 'screen -r' to restore your session. To detach your session again (i.e. move it into background) press Ctrl-A and then D (and you will see the normal command line prompt of your UNIX system) or simply close the connection. For more details about screen, see its documentation (for example, type 'man screen').