I still run some rhel5, and there were quite a few standard options that were not implemented by GNU.

Looking now is good, but looking in the past is also illuminating.

I generally trust busybox to give me both a uniform and compliant userland, certainly more than rhel5 coreutils.

I only chose the latest version because I figured it would have the most POSIXLY_CORRECT effects. Documentation seems to confirm this: the NEWS file documents added effects over time, but not removed ones, it seems.

I wouldn't necessarily be surprised if GNU coreutils from RHEL5 is old enough to be missing some options needed to comply with POSIX, or if it complied with older POSIX standards, but I think we're losing track here. GNU coreutils maintains essentially all of its functionality and options when in POSIXLY_CORRECT mode; there's really just a handful of differences and they are mostly around edge cases that few people care about, except insofar as it breaks their scripts, especially since in most cases they'll be using shell builtins instead which don't follow the POSIX behavior anyway.

I am not really arguing for or against GNU coreutils. I currently use GNU coreutils and would prefer GNU-compatible coreutils on my systems purely as a matter of muscle memory, regardless of whether it is in POSIX compatibility mode or not. That said, I don't think GNU coreutils are necessarily anything special, and the utilities that macOS and BusyBox provide are almost always perfectly fine with me, with some minor exceptions. I'm sure the same will be true if I ever try a uutils-based system. The only point to be made here is that at least as far as coreutils go, it doesn't really seem like POSIX compliance is a hindrance. If anything stopped macOS from using GNU coreutils, I suggest it's probably to avoid having more GPL software in macOS (especially post-GPLv3.) Though there could be multiple factors at play.

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chasil 2 days ago | parent [-]

And I'll get back to my original point.

When Debian demoted bash and migrated to the Almquist shell, there was great anguish from Ubuntu users of all tiers (Adobe was notable, IIRC).

That anguish was due to a decade that predated POSIX.2.

That was a substantial hindrance.

	▲	jchw 2 days ago \| parent [-]
		I absolutely remember Debian switching to Almquist shell, but that was about more than just POSIX compliance. IIRC a big deal at the time was that the cost of starting and using GNU bash all over the place was actually a measurable performance impact, and switching to dash improved on this. Also, bashisms became pervasive in scripts with /bin/sh hashbangs, which is definitely wrong no matter how you feel about POSIX. And anyway, this tangent doesn't feel terribly connected to this discussion thread since macOS never had this issue in the first place and this particular discussion thread was never really about UNIX shells...