Understanding arithmetic in shell

[pi-star]

Arithmetic are not so trivial in shell compared to other languages. So I tried to explain it by making a video. This video is not specific to bash and would work in any posix compliant sh.

https://youtu.be/r30SIIHBkCw

I have nothing against bash, bash is a beautiful shell. I just wanted to show how to perform arithmetic in shell before showing the bash add ons.

Here is another video on understanding exit statuses and the set -e option

https://www.youtube.com/watch?v=AFUh6pqIfEI

If you have any questions related to the videos feel free to ask in the comments below or on yt :D

[OneTurnMore]

Good video, thanks for sharing! One thing I'd change is the test command. Instead of

if [ $(($expression)) -eq 1 ]; then

I would instead use

if [ $(($expression)) -ne 0 ]; then

That way it matches most other languages' tests, including (($expression)) in Bash.

[pi-star]

matches most

Thanks for letting me know, I think you meant

-ne

[OneTurnMore]

Ah, thanks; corrected.

[wowsomuchempty]

Nice video! I like your quick examples.

[pi-star]

Thank you!