I would think the BSDs have at least as much Unix heritage as macOS, but they aren’t certified (“Certified Unix” is a rare breed. https://www.opengroup.org/openbrand/register/ lists only 13 products)
(Nitpick: it isn’t Unix™, it’s UNIX®)
The BSD's on the other hand could probably apply as they are one system (kernel and userland) with one governing body. But I doubt they really care to play the corporate standard mark game. They are UNIX and have always been so.
Not SCO, the Open Group. The Open Group is a not-for-profit industry consortium that maintains various standards and conformance programs for those standards, among which POSIX and UNIX are probably the most widely-known.
Novell gave the UNIX trademark and test suites to The Open Group; all SCO actually got was the right to sublicense the copyright to the AT&T UNIX software (but not the actual copyright itself). The former is much more important than the later because there are operating systems which pass the test suite (and hence are allowed to use the UNIX trademark) but which aren't based on AT&T-derived code (e.g. macOS, z/OS, EulerOS)
Note that Inspur K-UX you mentioned is no longer a certified UNIX because the vendor failed to pay the renewal fees. The same is true of Solaris.
Apparently, “conformance statements” are different from “registered products”. I guess one is self-reported and the other is externally verified?
Products get dropped from the register if the vendor fails to pay renewal fees. The product no longer appears on the register page, but the page on the product is not taken down and can still be directly accessed. This is what has happened to both Inspur K-UX and Oracle Solaris (and I'm pretty sure a few more over the years).
> macOS is a great system. It’s based on Unix but if you use it as just another Unix it will be a huge waste.
I mean, I guess it's at least true that it's "based on Unix" through its BSD lineage, but still an odd turn of phrase as, as you note, macOS has been an actual, registered, UNIX 03 system since 10.5.
Also, we might forget it now, but in the past there were a lot of UNIX that were quite different in small and large ways. The differences between Linux and Darwin might be as great as the differences between SunOS and Xenix, or indeed NeXTSTEP, back in the day. Or maybe not, that was before my time, but my point is that UNIX was not a monolith and there were incompatibilities and different ways of doing things. So I guess yeah, Linux might be what one of these might have become.
I just find it ironic that so many people are keen to compare macOS to UNIX and just assume that macOS has to be the weird outsider, even though the reverse is actually true. The same people also often assume Linux-isms are the way UNIX works, like the now-dead comment about macOS’ commands not supporting GNU options.
Like it or not, right or wrong, when people say "Unix" today, they mean Linux with GNU userland.
There are still a lot of IBM mainframes out there. Far less than there used to be, but IBM mainframes remain (even in 2020) a sector with many billions of dollars of annual revenue (if you add up hardware and software and services across both IBM and the ISV ecosystem). And the vast majority of those mainframes run z/OS. (They also run other operating systems – z/Linux, z/VM, z/VSE and z/TPF – but many of the sites running one of those other operating systems run z/OS as well.)
The UNIX component of z/OS is not merely a compatibility layer, a lot of operating system components and applications now rely on it. For example, the REST-based z/OS management console Zowe that IBM is now promoting runs under z/OS UNIX. My understanding is that IBM prefers (where possible) to develop new OS components and applications to run under z/OS UNIX rather than the traditional z/OS APIs. Anything written in Java (or other newer languages, such as node.js) is running on z/OS UNIX. So even if a z/OS site isn't doing anything directly on UNIX, they are almost certainly using OS components and applications which directly rely on it to function.
Obviously z/OS is absolutely dwarfed by Linux and macOS, but it is probably the healthiest of all the commercial Unixes – Oracle has put Solaris in maintenance mode, same for HPE and HP/UX, HPE killed Digital Unix years ago; AIX is healthier than Solaris or HP/UX, but I think z/OS is even healthier than AIX. z/OS licensing fees are a lot higher than AIX licensing fees, and the non-UNIX parts of z/OS (JCL, VSAM, CICS, IMS, etc) make it far harder to migrate off than AIX is.
No, it's not fair. Linux is just the OS kernel. UNIX covers interfaces, from APIs to shells and apps distributed by default, which are way out of the scope of Linux. That's the responsibility of Linux distributionsm.
And by the way, there are linux distributions that are certified UNIX
https://unix.stackexchange.com/questions/293396/is-there-a-l...
Moreover, UNIX is standardized. The drive for standardization was derived from the fact that all vendors of UNIX-like OSes were pushing their quirky vendor-specific things. In fact, even within Linux there is no widely established standard regarding basic interfaces, let alone UNIX.
With this in mind, do note that macOS's market share is significantly larger than the aggregate market share of Linux-based UNIX-like distributions.
How was I not aware of this? Thanks for the link! And you make a very good point regarding kernel vs OS. I assumed Linux == GNU/Linux in this context (so ignoring Android and others), but it certainly is a gross over simplification.
I don't understand why UNIX is such a big deal in 2020. Linux has won, and at least one BSD has binary compatability with Linux. If anything, we should be taking about Linux compliance.
Having no strong package manager story, yet being UNIX compliant, seems like an extremely bizarre priority choice.
Two BSDs (NetBSD and FreeBSD, no OpenBSD, don't know about Dragonfly), and a handful of Illumos distros (who call the feature LX-branded zones).
> If anything, we should be taking about Linux compliance.
Please no; a standard defined by one implementation isn't a standard.
Linux has another implementation: WSL 1
As for your second point, it just means that package management is irrelevant to UNIX (or POSIX) compliance. It did not prevent different package managers to appear over the years, because all the expected infrastructure was in place.
But did these UNIX package managers actually materialize? I guess my point is: is UNIX at all relevant? It had some really good ideas that were worth copying, but the world has moved on to greater ideas.
Obviously yes. I don't understand what is there so hard to understand.
I mean, just go learn about pretty much any field where you need to target a combination of platforms that don't agree on small arbitrary things, and how much wasted effort that consumes.
You've assumed that your perspective is the correct one without justifying it. Sure, standards are important, but UNIX doesn't seem to be a successful (or modern) one.
If you're interested in learning about why standards are "such a big deal" then you can start by discovering a phenomenon called linux fragmentation".
UNIX covers exactly zero of those. If UNIX was worthwhile, we wouldn't have Linux fragmentation or, indeed, an article explaining how to run UNIX scripts on a UNIX-compliant OS (sure as shit ain't a standard if it doesn't actually work).
Not sure about unix certified os's, but mac os has a much smaller install base than linux.
No, not really. macos's market share is about 4 times the aggregate market share of all Linux-based distributions.
...by which is meant, "Some differences between macOS, a certified Unix™, and systemd/Linux". Which is fine and valuable! But macOS is the most common Unix™, so the title as written is... entertaining.