Article & Journal Resources

November 28th, 2007 by Phil Hughes

While I was cleaning up my office I ran into the March 1986 issue of UNIX/WORLD, a long-since deceased magazine. I had saved this particular magazine because I am the author of the article featured on the cover: The Unix System on the IBM PC.

While what I am writing here may sound like humor, it actually is real. That is, it is about what has happened in the last 20 years. That article was about the beginning of the revolution. Our "real" computer in the office was a Codata 3300 which featured an 8MHz 68000 processor, 750KB of RAM and a 27MB hard disk. What did it cost? About 16 thousand 1984 dollars.

In those 20+ years, the price of 1000 times as much hardward has dropped to one tenth the cost of the Codata and the cost of a UNIX-like operating system has dropped to almost zero while the capabilities have expanded possibly one thousand fold like the hardware. In any case, on to the article.

First, lets look at the hardware requirements. Here is what I said in the article.

"To get going with a PC-based Unix system, the minimum hardware requirements are an IBM or compatible machine with at least 256K RAM, one floppy disk drive, and a 10-Mbyte hard disk."

Note that by "IBM or compatible" we are not talking about even an IBM AT. We are talking about an 8086-based PC. If you aren't laughing yet, read this again. One thousand times that much RAM is pretty much inadequate for today's UNIX/Linux system and one thousand times that much disk would be a bare minimum. And a floppy disk? Wow, we really did load UNIX and even early Linux distributions from floppy disks.

Much like your Linux system choices of today, there were choices back in 1986. In the article I looked at three versions of real UNIX (meaning software licensed from AT&T) and two clones. Also, much like today, I didn't come up with the one single best answer. Each had advantages and disadvantages.

The details of each choice are of little significance today but it is worth looking at the basics.

* PC/IX was a port of AT&T UNIX System III done by Interactive Systems Corporation for IBM. It was a decent port by lacked BSD programs such as the C-shell and the VI editor. It cost $900.
* VENIX/86 was a full UNIX port based on Version 7. (Note that Version 7 came before System III.) It included the C-shell, VI and the ability to run "medium model" (> 64K code space) programs. For an two-user license it cost $875. An eight-user license was $1075. For an additional $1000 you could get the source code for the drivers.
* Xenix 5, Release 2 is a port of UNIX System 5, Release 2 licensed to Microsoft (surprise) but then ported to the IBM PC by The Santa Cruz Operation. It is the largest, best documented (and probably least reliable) of the REAL UNIX ports. It comes in pieces with the basic system at $495, text processing at $295 and development system meaning C compiler and associated programs at $395.

That's it for the three real UNIX ports. Now, on to the clones.

* Coherent is a look-alike system from Mark Williams Co. It is designed to act more or less like UNIX Version 7. The best part is good documentation. Cost? $500.
* CO-IDRIS is the other look-alike. It was originally developed by Whitesmiths, Ltd. for the PDP-11 but then ported to the IBM PC. It is a "do it different" clone where program names are changed and, as strange as this sounds, it can run under MS-DOS. You get the whole thing for only $695.

Finally, the article offers a couple of hardware alternatives to offer better performance. Each consists of a card that plugs into a PC slot giving you a different processor on which to run UNIX.

* Opus 532 Persona Mainframe offers a National 32016 processor and a port of UNIX System V for only $3140 with an amazing one megabyte of RAM.
* The Sirtek VersaCard/Microcard gives you a Motorola 68000 processor running Unix System V for only $2095 with 256K bytes or RAM.

Now, what does all this mean? Well, over the years many people have asked why we bought a $16,000 dog of a computer in 1984, why we taught C programming classes on UNIX systems when MS-DOS was clearly what everyone was using and such. I guess the answer is that it gave us a head start on what has become the path to world domination.