UNIX is a spec. The point of being a "certified UNIX" is that the system conforms to SUS/POSIX and software developed targeting those specifications and their API are expected to run.
One might question the usefulness of SUS/POSIX in a world where most of the *nix ecosystem targets GNU, but saying it has no purpose beyond advertising is disingenuous.
Nothing could be further from the truth. Do you think these tests were created and maintained for free? Do you think the certification process happens on its own? Do you think there is no value in the whole Unix standard is stagnant, none-changing, and never reviewed or updated? And it all happens without cost? Do you think no one pays any attention to that?
Don't really understand your reply. Linux and GNU and {free,net,open}bsd are created and maintained "for free". Can things only have value if they cost money?
Is the unix certification only for large companies who can afford to throw money at the open group in order to get certified?
According to the wikipedia page:
> By decree of The Open Group, the term "UNIX" refers more to a class of operating systems than to a specific implementation of an operating system; those operating systems which meet The Open Group's Single UNIX Specification should be able to bear the UNIX 98 or UNIX 03 trademarks today, after the operating system's vendor pays a substantial certification fee and annual trademark royalties
Right.. Please tell me how this is not a meaningless certification?
FreeBSD is more unix than OS X, and would likely have no problems running the test suite, but is not certified as "real unix" because that certification is about money.
One might question the usefulness of SUS/POSIX in a world where most of the *nix ecosystem targets GNU, but saying it has no purpose beyond advertising is disingenuous.