[matheusmoreira]

I don't understand why people even care about POSIX in 2021. It's not like Linux distributions are POSIX certified. So many things can't be good because it's not in POSIX or because POSIX requires something else. People actually force themselves to write scripts in some mythical POSIX shell that nobody uses.

[arp242]

There are some cases where it makes sense. For example let's say I was developing something like a build script for ncurses: that runs on many different systems, and sticking to POSIX for compatibility makes sense there. There still quite a bit of stuff like that.

But a lot of the time I see people write some shell script that's Linux or BSD specific in the first place as "compatible" shell scripts. I don't see how that makes much sense. The only advantage I can see is that dash is a bit faster than bash or zsh, but it's not that much of a difference in real scripts.

[scbrg]

> The only advantage I can see is that dash is a bit faster than bash or zsh, but it's not that much of a difference in real scripts.

It also consumes quite a bit less memory, which can be relevant for shell wrappers or other long running scripts. That's the primary reason I started writing my scripts for dash rather than bash. The other advantages (portability, lack of cognitive overload caused by bash's infinitely long list of features and quirks) were an unforeseen bonus.

[crehn]

It's minimal effort to maximize compatibility and consistency, regardless of where the script may be run.

Shell scripts can run in a myriad of hosts, from VMs to stripped-down containers. When writing robust production code (not to say that shell scripts are ideal for that purpose), you'll want to minimize moving parts and risk surface, so that you can go home more confident that things will just work regardless of what you throw at it.