A brief history of Dell UNIX

“Dell UNIX? I didn’t know there was such a thing.”

A couple of weeks ago I had my new XO with me for breakfast at a nearby bakery café. Other patrons were drawn to seeing an XO for the first time, including a Linux person from Dell. I mentioned Dell UNIX and we talked a little about the people who had worked on Dell UNIX. He expressed surprise that mention of Dell UNIX evokes the above quote so often and pointed out that Emacs source still has #ifdef for Dell UNIX.

Quick Googling doesn’t reveal useful history of Dell UNIX, so here’s my version, a summary of the three major development releases.
↫ Charles H. Sauer

I sure had never heard of Dell UNIX, and despite the original version of the linked article being very, very old – 2008 – there’s a few updates from 2020 and 2021 that add links to the files and instructions needed to install, set up, and run Dell UNIX in a virtual machine; 86Box or VirtualBox specifically.

What was Dell UNIX? in the late ’80s, Dell started a the Olympic project, an effort to create a completely new architecture spanning desktops, workstations, and servers, some of which would be using multiple processors. When searching for an operating system for this project, the only real option was UNIX, and as such, the Olympic team set out to developer a UNIX variant. The first version was based on System V Release 3.2, used Motif and the X Window System, a DOS virtual machine to run, well, DOS applications called Merge, and compatibility with Microsoft Xenix. It might seem strange to us today, but Microsoft’s Xenix was incredibly popular at the time, and compatibility with it was a big deal.

The Olympic project turned out to be too ambitious on the hardware front so it got cancelled, but the Dell UNIX project continued to be developed. The next release, Dell System V Release 4, was a massive release, and included a full X Window System desktop environment called X.desktop, an office suite, e-mail software, and a lot more. It also contained something Windows wouldn’t be getting for quite a few years to come: automatic configuration of device drivers. This was apparently so successful, it reduced the number of support calls during the first 90 days of availability by 90% compared to the previous release.

Dell SVR4 finally seemed like real UNIX on a PC. We were justifiably proud of the quality and comprehensiveness, especially considering that our team was so much smaller than those of our perceived competitors at ISC, SCO and Sun(!). The reviewers were impressed. Reportedly, Dell SVR4 was chosen by Intel as their reference implementation in their test labs, chosen by Oracle as their reference Intel UNIX implementation, and used by AT&T USL for in house projects requiring high reliability, in preference to their own ports of SVR4.0. (One count showed Dell had resolved about 1800 problems in the AT&T source.) I was astonished one morning in the winter of 1991-92 when Ed Zander, at the time president of SunSoft, and three other SunSoft executives arrived at my office, requesting Dell help with their plans to put Solaris on X86.
↫ Charles H. Sauer

Sadly, this would also prove to be the last release of Dell UNIX. After a few more point release, the brass at Dell had realised that Dell UNIX, intended to sell Dell hardware, was mostly being sold to people running it on non-Dell hardware, and after a short internal struggle, the entire project was cancelled since it was costing them more than it was earning them.

As I noted, the article contains the files and instructions needed to run Dell UNIX today, on a virtual machine. I’m definitely going to try that out once I have some time, if only to take a peek at that X.desktop, because that looks absolutely stunning for its time.