@thomholwerda It's reasonable to assume that Apple's Unix certification is primarily meant to fulfill requirements for procurement rules. See also what Microsoft did to comply with FIPS 151-2 back in the day with the Windows NT POSIX subsystem.

The macOS certification is for UNIX 03 and only for that. I doubt that in practice anybody cares all that much about a standard that is well over 20 years old, which presumably was kind of your point anyway.

@thomholwerda An interesting look at the standards compliance game.

The atime behavior changed on Linux similarly as having reads cause writes is a bit bonkers.

Likewise writing core files really only causes trouble.

More importantly for actual development, be aware that OSX fork() has such impressive CAVEATS that you wish you never read the manpage: https://www.unix.com/man-page/osx/2/fork/

This, and not missing UUCP support is what makes MacOS not-a-Unix.

@thomholwerda I figured at the very least you had to run a file system with case sensitivity. Interesting the other tweaks necessary to get it to pass.

@thomholwerda they really volkswagenned that test suite

@thomholwerda a few people have hinted at it already, but I want to state it more explicitly: a key question with any certification is "who is this certification for? who cares and why?"

in this case, clearly, it's not meant for UNIX nerds. i don't know who specifically it's meant for, though a commenter's probably right that it's for procurement

@thomholwerda@exquisite.social Apple is about as UNIX-certified as windows technically is

@thomholwerda We take great pride, having read this, in having a real, actual, no shit Unix-03 box sitting right here, with no bullshit hacks required:

```
Solaris 10 1/13 s10s_u11wos_24a SPARC
Copyright 2013 Sun Microsystems, Inc. All rights reserved.
                          Use is subject to license terms.
Assembled 17 January 2013
```

@thomholwerda great article, thanks :)

> I can guarantee you with 100% certainly not a single macOS installation in the entire history of macOS ... has implemented even half of these changes.

believe it or not, I have made the majority of those changes all to the same mac before!