what makes an OS a Unix OS?

[billdotson]

I was recently thinking about trying OpenSolaris and asked what type of OS it is. I know the kernel of the OS is the OpenSolaris kernel but how exactly is OpenSolaris a Unix OS if it uses a OpenSolaris kernel? Doesn't a Unix system use a Unix kernel?

So in simple terms what makes an OS a Unix system and not it's own system like OpenSolaris??

[Rhapsody]

Technically speaking, adherence to the Single UNIX Specification (http://en.wikipedia.org/wiki/Single_UNIX_Specification) is what's required to truly be a "Unix OS". Several OSes (like BSDs and Linux distros) are referred to as "Unix-like" though.

[Brunellus]

I was recently thinking about trying OpenSolaris and asked what type of OS it is. I know the kernel of the OS is the OpenSolaris kernel but how exactly is OpenSolaris a Unix OS if it uses a OpenSolaris kernel? Doesn't a Unix system use a Unix kernel?

So in simple terms what makes an OS a Unix system and not it's own system like OpenSolaris??
the present Solaris (and its successor, OpenSolaris) is lineally descended from UNIX System V version 4 (http://en.wikipedia.org/wiki/UNIX_System_V), and thus is strictly speaking, a UNIX.

GNU/Linux is NOT a UNIX--the GNU is a clue: "GNU's Not UNIX."

[billdotson]

oh ok I will read that page. thanks

[SunnyRabbiera]

But linux is indirectly a relitive to unix, more or less Minix as that was what inspired Linus Torvalds to come up with a alternative to it.
I concider Linux and BSD as both relitives to unix, but they are only relitives by marriage :D
You know, like second cousins twice removed, soliaris is in this branch too.