In some ways, Apple's adherence to UNIX specifications probably makes macOS less useful for you. For example, I wish that grep on macOS was closer to GNU grep. When I look up commands online, I often find answers based on the GNU implementations. Those often work on macOS, but sometimes don't (or have subtly different behavior) because macOS is adhering to the UNIX specification rather than to what those utilities do on the vast majority of systems out there.
I don't think Apple would be removing UNIX-like tools from macOS even without certification. They know how valuable it is that most developers use their systems. Even Microsoft went so far as to implement the Windows Subsystem for Linux for developers. At this point, I think that UNIX certification makes macOS less compatible with the tools and help out there which generally targets Linux. Usually the differences are small, but they certainly can be meaningful.
I hope you're right but I'm not as confident. Corporations - Apple included - have been guilty of some surprising ignorance when it comes to things like this. I'm thankful for this certification circus to continue so that we don't need to test your theory.
UNIX certification is not the reason why macOS utilities are missing options compared to GNU - UNIX standards say you have to have certain options which work a certain way, they don’t prohibit adding additional options as vendor extensions. The reason is that Apple’s investment in improving these tools is minimal because it is a low priority for them, and because people who get annoyed by this often just end up installing the GNU tools anyway (using Homebrew or MacPorts)
In fact, GNU/Linux systems have been certified as UNIX in the past, by a couple of different Chinese vendors (Inspur K-UX, Huawei EulerOS)-which shows use of the GNU tools is no inherent obstacle to certification. The reason these vendors stopped, I suspect, is the money it was making them was smaller than the certification costs and UNIX trademark license fee
Outside of coreutils, let's consider bash and ksh88.
The two have differing behavior in several areas (coprocesses, alias handling, final pipeline fork, etc.), but this divergence in behavior happened before POSIX.2 and the standardization of the POSIX shell, which is largely a subset of ksh88.
The gist is that activating a mode for POSIX compliance will generally remove functionality, because the standardization happened a decade after development began, and the standards themselves were excessively conservative in adherence to System V.
I've seen that useful GNU extensions are generally adopted by BSD, but much more slowly by POSIX.
That does not serve UNIX well. Someone should challenge the Austin Group for effective control of UNIX standardization.
To get UNIX certification, you can just patch it to make POSIXLY_CORRECT=1 the default.
Or even don’t patch the utilities, and just patch /etc/profile to set POSIXLY_CORRECT=1 globally.
UNIX certification requires that the system have a mode of operation available which passes the test suite; the existence of config settings which if changed from their defaults produce standards violations is not in itself a standards violation.
macOS still has a bunch of GNU tools, but they appear to be incompatible with GNU tools used everywhere else, because they're so outdated.
The problem with the old tools is that I don't have admin rights at work so it's not easy to install coreutils. Or even homebrew.
I can understand why they did it though. Too many tools these days advocate just piping some curl into a root shell which is pretty insane. Homebrew does this too.
Right, but I think GP's point is that if Apple didn't feel pressured to get macOS UNIX-certified, then they wouldn't even bother to be UNIX-like. That is, all sorts of UNIX-required command-line tools would start to disappear from the default install, and things like POSIX conformance would take a back-burner, etc.
Not sure if I agree with that, but that's what GP seems to be suggesting.
> For example, I wish that grep on macOS was closer to GNU grep.
This has nothing to do with UNIX conformance; this just comes from macOS's BSD background, which does not use the GNU core utils. If the Linux folks wanted to go through UNIX conformance testing, they wouldn't have to switch away from GNU tools. And macOS could swap out the BSD-sourced tools for GNU tools and still get their UNIX certification.
It's not just about going through a song-and-dance. It's about making an OS that has different behavior - often very tiny differences, but differences that would make the distro worse for most users.
Isn’t it rather that Darwin was based on BSD 4.4? I’d imagine GPL 3.0 is a bigger impediment to them ever migrating to GNU tools than any desire to be UNIX certified.
It derives from 4.4 BSD but it's more than that.
macOS includes a woefully outdated bash 3.2 due to GPL 3.0; they switched to zsh long ago.
Even if macOS wasn’t UNIX-certified, Apple would still be unwilling/unable to include the GNU software due to the license. I can’t see the Apple of today implementing a full suite of non-GNU software but with GNU-style options either.
So, POSIX compliant or not, there’s probably no world where `grep -P` works out of the box on a Mac.
