14. THE ORAL TRADITION


Unix is hard to learn. The process of learning it is one of multiple small epiphanies. Typically you are just on the verge of inventing some necessary tool or utility when you realize that someone else has already invented it, and built it in, and this explains some odd file or directory or command that you have noticed but never really understood before.

For example there is a command (a small program, part of the OS) called whoami, which enables you to ask the computer who it thinks you are. On a Unix machine, you are always logged in under some name--possibly even your own! What files you may work with, and what software you may use, depends on your identity. When I started out using Linux, I was on a non-networked machine in my basement, with only one user account, and so when I became aware of the whoami command it struck me as ludicrous. But once you are logged in as one person, you can temporarily switch over to a pseudonym in order to access different files. If your machine is on the Internet, you can log onto other computers, provided you have a user name and a password. At that point the distant machine becomes no different in practice from the one right in front of you. These changes in identity and location can easily become nested inside each other, many layers deep, even if you aren't doing anything nefarious. Once you have forgotten who and where you are, the whoami command is indispensible. I use it all the time.

The file systems of Unix machines all have the same general structure. On your flimsy operating systems, you can create directories (folders) and give them names like Frodo or My Stuff and put them pretty much anywhere you like. But under Unix the highest level--the root--of the filesystem is always designated with the single character "/" and it always contains the same set of top-level directories:

/usr
/etc
/var
/bin
/proc
/boot
/home
/root
/sbin
/dev
/lib
/tmp
 

and each of these directories typically has its own distinct structure of subdirectories. Note the obsessive use of abbreviations and avoidance of capital letters; this is a system invented by people to whom repetitive stress disorder is what black lung is to miners. Long names get worn down to three-letter nubbins, like stones smoothed by a river.

This is not the place to try to explain why each of the above directories exists, and what is contained in it. At first it all seems obscure; worse, it seems deliberately obscure. When I started using Linux I was accustomed to being able to create directories wherever I wanted and to give them whatever names struck my fancy. Under Unix you are free to do that, of course (you are free to do anything) but as you gain experience with the system you come to understand that the directories listed above were created for the best of reasons and that your life will be much easier if you follow along (within /home, by the way, you have pretty much unlimited freedom).

After this kind of thing has happened several hundred or thousand times, the hacker understands why Unix is the way it is, and agrees that it wouldn't be the same any other way. It is this sort of acculturation that gives Unix hackers their confidence in the system, and the attitude of calm, unshakable, annoying superiority captured in the Dilbert cartoon. Windows 95 and MacOS are products, contrived by engineers in the service of specific companies. Unix, by contrast, is not so much a product as it is a painstakingly compiled oral history of the hacker subculture. It is our Gilgamesh epic.

What made old epics like Gilgamesh so powerful and so long-lived was that they were living bodies of narrative that many people knew by heart, and told over and over again--making their own personal embellishments whenever it struck their fancy. The bad embellishments were shouted down, the good ones picked up by others, polished, improved, and, over time, incorporated into the story. Likewise, Unix is known, loved, and understood by so many hackers that it can be re-created from scratch whenever someone needs it. This is very difficult to understand for people who are accustomed to thinking of OSes as things that absolutely have to be bought.

Many hackers have launched more or less successful re-implementations of the Unix ideal. Each one brings in new embellishments. Some of them die out quickly, some are merged with similar, parallel innovations created by different hackers attacking the same problem, others still are embraced, and adopted into the epic. Thus Unix has slowly accreted around a simple kernel and acquired a kind of complexity and asymmetry about it that is organic, like the roots of a tree, or the branchings of a coronary artery. Understanding it is more like anatomy than physics.

For at least a year, prior to my adoption of Linux, I had been hearing about it. Credible, well-informed people kept telling me that a bunch of hackers had got together an implentation of Unix that could be downloaded, free of charge, from the Internet. For a long time I could not bring myself to take the notion seriously. It was like hearing rumors that a group of model rocket enthusiasts had created a completely functional Saturn V by exchanging blueprints on the Net and mailing valves and flanges to each other.

But it's true. Credit for Linux generally goes to its human namesake, one Linus Torvalds, a Finn who got the whole thing rolling in 1991 when he used some of the GNU tools to write the beginnings of a Unix kernel that could run on PC-compatible hardware. And indeed Torvalds deserves all the credit he has ever gotten, and a whole lot more. But he could not have made it happen by himself, any more than Richard Stallman could have. To write code at all, Torvalds had to have cheap but powerful development tools, and these he got from Stallman's GNU project.

And he had to have cheap hardware on which to write that code. Cheap hardware is a much harder thing to arrange than cheap software; a single person (Stallman) can write software and put it up on the Net for free, but in order to make hardware it's necessary to have a whole industrial infrastructure, which is not cheap by any stretch of the imagination. Really the only way to make hardware cheap is to punch out an incredible number of copies of it, so that the unit cost eventually drops. For reasons already explained, Apple had no desire to see the cost of hardware drop. The only reason Torvalds had cheap hardware was Microsoft.

Microsoft refused to go into the hardware business, insisted on making its software run on hardware that anyone could build, and thereby created the market conditions that allowed hardware prices to plummet. In trying to understand the Linux phenomenon, then, we have to look not to a single innovator but to a sort of bizarre Trinity: Linus Torvalds, Richard Stallman, and Bill Gates. Take away any of these three and Linux would not exist.

In The Beginning Was The Command Line
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