# screen

**Attention**: [tmux](https://wiki.math.uzh.ch/public/books/public-wiki/page/tmux) is a more modern and powerful tool for the same task as `screen`

screen is a useful tool to keep long time tasks (a.e. magma, matlab) running on a computer without keeping your session online during the whole computation:

- Initial Start: 
    - open a console and connect through SSH to the machine you want to run the task on (most likely: compute.math.uzh.ch) by typing the host name: **\[user@tlX\] compute** and enter your password (there is a script called 'compute' which does nothing else than 'ssh compute' - in our evironment it's not necessary to type 'ssh compute')
    - type **screen <application name>** . F.e.: `screen maple`
- Detach: 
    - to detach from screen ("send it to background"), press **Ctrl + A + D**
    - you now can log off from the terminal and your task will keep running
- Attach again: 
    - if you want to check progress of your computations, log into the machine where your task is running like you did before
    - use **screen -raAd** to connect to your task