Creating Unix script to sleep better

Question

I know that I try to work to late in the night and that at this time I'm absolutely unproductive, I work for 5 minutes then switch to a link seen on youtube, then come back to my work, waste some more time on he internet... until 2 in the morning, hour at which I am able to discplinate myself and go to bed.

How could I write a script that automatically shuts down the computer at midnight?

I think I have to use the command crontab and write the following command in it

shutdown 00:00

I'm asking you if what I do is right, first and optimal or if it exists other ways to do it.

Here is what I made

myComputer:~$ crontab -l
# m h  dom mon dow   command
 55 23 *   *   *     /home/Marine1/soundOfSilence
 00 00 *   *   *     shutdown

Here is what is within /home/Marine1/soundOfSilence

#!/bin/bash

mpg123 /path/to/short/sound.mp3
shutdown 5

Answer 1

I'd suggest doing something a bit different. Your approach is fine, but might prove annoying, when you got to do something sometime late and PC shuts down in the middle of the work. Instead, I'd suggest that you write a simple script that does something to bring your attention few minutes before shutdown, so you can prepare yourself.

The simplest approach would be to just run shutdown with 5 minute delay - it sends a warning. However, it might not be enough, and if you want to make sure that you notice it, you might do something more invasive, e.g. play some sound.

Example script would look more or less like this(I hope it's correct):

#!/bin/bash

mpg123 /path/to/short/sound.mp3
shutdown 5

mpg123 can be used to play audio MPEG. If you choose other format, you will need to change the command, but it should be easy enough to google.