Sure, but the pojt here is that if we say "Write in X" we generally understand it to mean "Treat X like a standard and don't get too colloquial with the stylings."
Pedantry is worthwhile, but it can be a diminishing returns game.
On the example of 'echo \n' - it's not defined in POSIX, therefore a script written in "POSIX shell" must simply never hit that case.
TFA kinda implies you can't target POSIX shell. That's silly, of course you can. The question is, what tools are there to check for compliance. Whether running on 14 shells is a good such tool - idk. Something specifically searching for POSIX violations might be better.
`local` for example is present in many shells (almost all of them), but they decided to leave it out uniquely because of ksh93 (scope is different). It became undefined behavior.
When the spec was written, ksh was important. Since then, it has only been revised but not updated and I consider it to be obsolete.
So, if you follow POSIX strictly, you then lose local scope on functions, which is more likely to cause bugs and hard to catch with a linter like you suggested. You're left with a broken feature set (on many other angles too) that is not actually practical. Even spellcheck makes concessions.
I use long options in scripts so that you can actually understand which options are used. Short options are for interactive shells since those commands nobody is really gonna look at again.
`echo` in most shells is not `/bin/echo`, it's actually an internal implementation (external echo means forking at every output, which is super slow).
The portability of other cor utils is also a clown fiesta, and most likely the best solution for now is "use gnu", which sometimes feels like "best viewed in internet explorer"-era shinenigans.
The blog post stresses this, the difference between POSIX and portability.
If you want portability, testing is better for now. One of the goals of these projects is to more precisely capture a retrospec (what actually works, not what was specified), it's the same thing they did with HTML5.
How so?
Can you give an example that should work according to the POSIX spec but doesn’t in a POSIX compliant shell?
The example in the post is just some behavior the POSIX spec doesn’t specify, so obviously you wouldn’t be allowed to do that when targeting POSIX.
https://stackoverflow.com/questions/11376975/is-there-a-mini...