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Comment by arendtio | Hacker News Reader

I think one of the biggest problems is the inconsistent runtime environment. I mean, yes, you can just say fuck POSIX and code for Bash only, but then again, not even Bash is consistent across its versions. Just to give an example: The infamous `set -e` behaves quite differently across different shells

https://www.in-ulm.de/~mascheck/various/set-e/

And those are just POSIX compliant shells. I mean this doesn't matter if you just want to write a script for yourself but becomes frustrating when you want to level up you shell skills and write cross-platform scripts ;-)

That said, I have to add that I love shell scripting... I am not exactly sure why, but I guess it is because it lets you build powerful things with very few lines of code.

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Yes. I have already been burned by it. Some scripts were developped without bashism in order to be portable on posix shells. Initially, they were used on ksh. Recently, they were tested only on bash. I had to use them on ubuntu (where /bin/sh is a link toward dash). Nothing was working and it was hard to identify the issues. I have changed the first line of all scripts -> problem fixed. Portability of scripts is an illusion: all you can do is test on all the target shells. If you do not have budget for testing on other shell than bash, do not waste your time trying to write portable code.

I agree, and I like having those ‘oh wow, I can do that in bash? That’s dangerous, but awesome’ moments just by researching how to get stuff done. Really people don’t know what they’re getting themselves into when they start down the shell scripting path.

When isn't this true, though? JavaScript behaves differently based on your browser and version. C runs differently based on your compiler version and system libs. This is just the nature of software.

You do realize standardization exists to avoid just that?

What's your point? Shell is also standardized by POSIX.

Shells, C, and JavaScript all have standards. That doesn't mitigate versioning and platform differences entirely.

I think the particular problem with shells is that POSIX (the standard) didn't really keep up with the development of new features over time. Instead, the different implementations introduced new features and nowadays there are some features which are quite common but not part of the standard (just from the top of my head: curl/wget; mktemp; bashisms).

With JS that is different. Yes, every browser has a few extra bits here and there, but there is very little that many browsers have that is not part of the standard. With compilers, it is different because the developer can decide which one he wants to use at build-time. After that, his program still might behave differently on different platforms (depending on APIs, etc.) but in general, the language that he uses behaves the same. With shell scripts that is not the case as the behavior depends on the run-time shell and the developer has very little influence on which shell will be used.

So while you are right that every programming language has this problem, some are better at managing it than others and shells are particularly bad at it in my opinion.

and to make things worse, macOS ships with a 12 years old version of Bash.

Use Homebrew version.

https://formulae.brew.sh/formula/bash

Indeed, I have been burned by that... Wrote a script which worked perfectly fine with Linux. Tried it with MacOS...

Oh gosh, it was such a pain work around those old bugs...

Does someone know why Apple doesn't update the bash?

I believe Apple ship the last version of bash released under GPLv2, and do not ship versions under GPLv3.

Apple has a problem with GPL3, not sure what exactly but that’s the underlying issue.

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