[vcf-midatlantic] ESIX System V

Kenneth Seefried kjseefried at gmail.com
Fri Sep 20 00:57:32 EDT 2019

TL;DR: Definitely worth preserving.  If no one else, the guy at
https://virtuallyfun.com/ is into various versions of i386 Unix.

Long Version: I worked for a hardware OEM and some related firms in the
golden days of SVR4 on i386.  I ran daily pretty much all of them,
installed them daily/weekly, beat my head on the desk frequently.  We had
source trees for virtually all of these which we spent a *lot* of time
pouring through.  Code was written and debugged.  My $DAYJOB was
driver/integration/testing/admin work on this stuff.

> "*ESIX* - Esix System V Release 4.0 unifies all major versions and
> derivatives of UNIX such as AT&T System V Release 3.2, Berkeley Software
> Distribution (BSD) 4.2 and 4.3, SCO UNIX 3.2, and Microsoft XENIX. In
> addition, key features of Sun Microsystems SunOS? have been incorporated. "
That's pretty much a generic description of System V release 4 for i386.
It was obviously replacing SVR3, Xenix & SCO.  Hard to not pull in 4BSD.
The reference platforms for SVR4 were i386 and SPARC, so yeah, key features
of SunOS were in there.

>   Everex did more than distribute it; they started with AT&T SysV, wrote
> most of the drivers, and integrated the BSD extensions.
They might have written the the drivers for some Everex specific hardware,
but unless you have some evidence, the Everex source code I saw was pretty
much stock SVR4/i386.  Certainly nothing I'd call "most" of the drivers.
Or even "a few".  I think there was was some Everex motherboard specific
tweaks (didn't they have their own spin on a memory or cache controller?
Something like that...I forget.) and a disk controller or two.  But it's
been nearly 30 years, so I could be wrong.

And exactly what BSD extensions did they integrate that weren't part of
stock SVR4?  I don't recall that "#ifdef ESIX" was a thing.

Wow. If all of that is true, then this would seem to be a very desirable
> unix system. Maybe even the holy grail of unixes. However the devil is in
> the details. Maybe it had some flaws? I hadn't heard of it, but with those
> collection of features, you would think it would be extremely well known
> (maybe it is, maybe I'm cloistered)
Historical Context: Given a couple of competent Unix savvy hackers, it was
pretty easy to bring up the reference SVR4 on any random, suitably generic
i386 (486, 586) motherboard and common I/O boards; there were drivers
already for the common chipsets and a lot of (E)ISA devices.  And there
were a number of consultancies who would do the port for you for a modest
fee.  So lots of vendors paid a few bucks so they could say "see....we got
Unix too!".  Good times.

ESIX was an "you-get-an-A-for-effort" SVR4/i386.  They had some really
good, dedicated folks who worked very hard.  They tried to take it up a
notch above a generic SVR4 distro.  Everex wanted to be considered more
"workstation" than "bog standard generic PC box".  But they never had very
many folks working on Unix, and never with many resources.  There were a
tiny handful of technical support people (like, 3-4 maybe), which was rough
(even for Unix savvy customers).

For me, it wasn't the holy grail.  YHGMV.

Compare it to Dell SVR4, which clearly had much more investment and
actually had things they did that no one else did: a reasonably well
resourced support organization (mostly of the time), tuned drivers, a nifty
and actually useful auto-configuration system, an X11 "office suite" of
apps (admittedly, not that great), a curated selection of Open Source tools
(like gcc, perl, emacs, tex) on the distro tape at a time when downloading
and compiling such things wasn't always trivial (and, like Solaris 2, you
otherwise had to pay for a C compiler).

That was my daily driver for years...really nice for the time.  Still
turned out to not be a viable product in the long run, but that's a
different story.


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