UNIX 9th edition ????

[Guy Harris]

>According to a footnote in Bach's book, System IV existed internally,
>but evolved into System V before the commercial release.

"UNIX 4.x", for various values of "x".

>> UNIX System III was the commercial name for USG UNIX 3.0 and UNIX System
>> V was the commercial name for UNIX 5.0.  Because of the marketing hoopla
>> about UNIX System V being the "standard" UNIX, further commercial
>> releases retained the name "UNIX System V".  This is expected to continue.
>
>Is USG UNIX 5.0 the same as UNIX v5? Funny, what happened to all the
>IPC features, terminfo and all the other neato stuff when they went to
>UNIX v6?

"V5" in what sense?  There was a "V5" that some universities got (I
think Harvard had it, for instance), but that antedated V6.  The only
connection between it and System V is that it was a remote ancestor of
System V (and of all the other later UNIX flavors).

I think the IPC stuff first showed up on that particular branch of the
tree in one of the UNIX 4.x releases ("System IV", if you will).  V6
didn't have it, or "terminfo" and company, because V6 came out before
System V (which may explain part of why they went to Roman numerals with
System III). 

System V was, basically, UNIX 5.0 (just as System III was, basically,
UNIX 3.0.1 - yes, 3.0.1, as I remember that's what "uname" was set up to
claim it was; I think the ".0.1" was a minor bug-fix release after 3.0). 
I think System V Release 2 was, or would have been, "UNIX 6.0" - I
remember some comments or SCCS IDs or something that indicated such -
and I think I saw some "7.0" stuff lying around in S5R3 or some other
post-S5R2 release.