Mac OS X Leopard is Now Officially Unix

An anonymous reader writes "Mac OS X Leopard is now officially Unix, according to the Opengroup." I know everyone out there was really worried about this one. Welcome to the August news vacuum!

Comments

It passed the certification

[morgan_greywolf]

The Open Group's trademark-protected Unix certification program determines who gets to call themselves 'UNIX'. Just because an OS is derived from the original Unix sources at some point doesn't make it a 'UNIX'. You get to call it a 'UNIX' if it passes the Open Group's tests, which determine if it meets the specifications. In this case, Mac OS X 10.5 'Leopard', only when running on Intel Macs, not PPC Macs or any other box was found to meet the UNIX 03 specification.

Re:No Linux?

[Swampash]

Does this mean that OSX is more Unixy than Linux?

As of 10.5, OS X is UNIX. Linux is "UNIX-like".

Correct answers

[morgan_greywolf]

Was Tiger (10.4) certified?

No.

Did Apple even try to certify Tiger?

No.

Why (not)? If not then why start now with Leopard?

Well, if you want certification, you gotta start sometime. I seem to remember the Open Group getting into a little tussle with Apple over Apple's use of the UNIX trademark in its advertisements. The Open Group owns the name UNIX, so you don't get it to call it UNIX unless the Open Group says so. I think this may be part of the arrangement they entered into....

Anyway, the process is expensive. So expensive that none of the *BSDs are certified, no Linux, of course, is certified (yes, a Linux distro could be), etc.

The members of the UNIX club are few: IBM, HP, Sun, NEC, The SCO Group, and a few others.

Re:I think its a major achievement

[TheRaven64]

Part of the problem with this certification is that it needs to be renewed for each version. For Linux, it's not feasible, because it certifies entire operating systems, rather than kernels. The Single UNIX Specification covers a few basic devices, a huge number of C APIs and a set of useland tools (e.g. shell, C compiler, etc). Linux implements a page or two of the spec, and system calls that allow glibc to implement a load more. The GNU tools implement a lot more beyond that.

A distribution of Linux could apply for certification, but the certification would only be valid for the exact version; update the kernel, any of the GNU utilities, etc, and it would stop being UNIX(TM) (although, for PR purposes, if FooLinux 10 is UNIX, then people probably won't care that FooLinux 10.0.1 hasn't been certified).

The certification is more than just PR, however. Any product that has the certification is guaranteed to comply with the SUS spec. This means any software written to the specification will work. I'm glad OS X is getting it, since there are a few gaps in the implementation on 10.4 that should have been plugged before they got this. I've written code to the SUS spec before, and had it work flawlessly on Solaris but have minor issues on FreeBSD, Linux, and OS X. The more operating systems that conform to SUS, the easier it is to write cross-platform code. Whether they get the certification is irrelevant, to a degree.

Re:I think its a major achievement

[larkost]

"Unix" (notice the capitol U) is a specific certification whose criteria Apple has met (and paid for the right to use that designation). Generally people refer to things that have their roots in the old Bell Labs UNIX as "unix" or "unix-like" (notice the lower case u's). This is more of a philosophy of how things should work ("everything is a file, even when its not").