Did Linux Kill Commercial Unix?
Sales of commercial Unix have fallen off a cliff. There has to be something behind this dramatic decline. Has Linux killed its ancestor by becoming a perfectly viable replacement, like an operating system version of Invasion of the Body Snatchers?
The Beginning of Unix
The initial release of Unix occurred fifty years ago in 1969, at Bell Labs, a research and development company owned by AT&T. Happy birthday, Unix. Actually, at that time it was still called Unics, standing for UNIplexed Information and Computing Service. Apparently, no one can recall when the “cs” became an “x.” It was written on a DEC PDP/7 computer, in DEC assembly language.
There was a need within Bell to produce typeset patent applications. The Unix development team identified that need as an opportunity to get their hands on the newer and more powerful DEC PDP/11/20 computer, so they quickly produced a typesetting program to generate the patent applications. After this, the use of Unix steadily grew at Bell.
In 1973 Version 4 of Unix was released, re-written in the C programming language. The introduction to the accompanying manual had this to say: “The number of UNIX installations is now above 20, and many more are expected.” (K. Thompson and D. M. Richie, The UNIX Programmer’s Manual, 4th ed. November 1973.)
How little they knew! In 1973 Ken Thompson and Dennis Ritchie, two of the core Unix architects, presented a paper at a conference about Unix. Immediately they received requests for copies of the operating system.
Because of a consent decree that AT&T entered into with the US government in 1956, AT&T had to stay out of “any business other than the furnishing of common carrier communications services.” The upshot was they could license products from Bell Labs, but they couldn’t wholeheartedly productize them. So the Unix operating system was distributed as source code with a license, and costs that covered the shipping and packaging and a “reasonable royalty.”
Because AT&T couldn’t treat Unix as a product and didn’t put the usual wrap-around on it, Unix was given no marketing. It came with no support and without bug fixes. Despite this, Unix it spread into universities, military applications, and eventually the commercial world.
Because Unix had been rewritten in the C programming language, it was relatively easy to port it to new computer architectures, and soon Unix was running on all sorts of hardware. It had broken out of the confines of the DEC product range and could now run almost anywhere.
The Rise of Commercial Unix
In 1982, following another consent decree, AT&T was forced to relinquish control of Bell, and Bell was broken up into smaller, regional, companies. This upheaval released AT&T from some of their previous strictures. They were now able to productize Unix formally. In 1983 license fees were raised, and support and maintenance were finally available.