Guru of the Unix gurus

He brought the full force of his intellect to bear on his work, and it showed. Stevens' books are regarded as models of the genre. "I remember he shocked me, because I ran into him at some conference and he said, 'I wish I'd brought the 'Perl Cookbook' so I could have had you autograph it for me,'" says Christiansen. "I don't consider my books to be in anywhere near the same league of serious, hard work as his. That he would say to me 'I should have got your autograph' was like Dennis [Ritchie, one of the original authors of Unix] saying it."

"He gave extremely cogent explanations of what's going on," says Rose. "His books are so much more readable than most computer books. A lot of authors look at the documentation and rewrite it with little or no interpretation. He took the time to understand."

His perseverance was an artifact of an apparently ferocious curiosity. "When I hit something that I don't understand, I take a detour and learn something new," said Stevens in an interview two years before his death. "This often makes my books late by a few months, but I think accuracy and completeness are essential."

It may have been Stevens' sense of himself as an outsider that inspired this level of dedication. He and his brother and sister were copper-mining brats, born in Africa to a metallurgical engineer; they divided their childhood among northern Rhodesia (now Zambia), Utah, New Mexico, Washington and South Africa. Stevens didn't start out in computer science at all, but in aerospace. It just happened that he graduated in 1973, when Boeing was laying off thousands of aerospace engineers. Programming, like piano, was a late acquisition that took.

"I really believe that my background is fundamental to the success of 'Unix Network Programming' and my other books," he said. "That is, I was not one of the developers at Berkeley or AT&T, so the writing of UNP was not a 'memory dump.' Everything that is in the book I had to dig out of somewhere and understand myself."

In fact, Stevens belonged to the generation of Unix geeks who pored over not-exactly-legal copies of John Lions' legendary commentary on the Unix source code. Lions firmly believed that no one could understand the theory of computer science without concrete examples, ideally embodied in C programs. Stevens seems to have agreed.

"Certainly his books do that. He tends to walk you through the code," says Hanson, who led the graduate seminars at the University of Arizona where Stevens discovered the Lions books. "It's not like you can read this stuff while you're sitting in front of the television. It's a particular style of learning about software that requires a very heavy investment upfront. But it pays off."

It's not as easy, or as obvious, as it sounds. Publishing code legibly is hard work, and calls for stubborn authors who insist on the best tools for the job. Stevens greatly admired and strove to emulate Donald Knuth, who wrote "The Art of Computer Programming," and Brian Kernighan, "The C Programming Language," whose books are as beautifully laid out as they are brilliantly written.

For his own work, he insisted on a text-formatting tool even more venerable and revered than Knuth's Tex. "Rich had told me that he gets to send 'troff,'" says Christiansen in awed tones, referring to a fairly archaic layout program. "He still used all the cool old tools, and he prepared camera-ready copy for the publisher. It's very, very rare that authors aren't forced to use Microsoft Word or unadorned SGML." Controlling his own means of production allowed Stevens to explain difficult concepts visually as well as verbally -- hence the apparently perverse theme of "TCP/IP Illustrated." Visualizing a protocol? It sounds crazy, but it works.

His books are so good that they have come to symbolize intelligence. In "Wayne's World II," Garth's girlfriend carries a copy of "Unix Network Programming." Stevens discovered this when he took his 13-year-old son to see the film. His son grabbed his arm and said, "Dad, that's your book!"

"I couldn't believe it," he told programmer Trent Hein. "My book was used to define the ultimate geek, and suddenly my son thinks I'm really cool."

His son was right.

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