I’ve written about Diomidis Spinellis and his wonderful Unix repository before. It’s a single place you can go to get most of the publicly available Unix source code. As I’ve said previously, one of the best ways of becoming a master developer is to read the code of the masters. Spinellis’ repository allows you to do just that and is definitely worth checking out if you haven’t already.
For the last five years Spinellis and Paris Avgeriou have been researching the evolution of Unix and have produced a paper documenting their work. You can see read a summary of the work at the above link or you can read the whole paper here.
It’s an interesting study and definitely worth taking a look at if you have any interest in Unix, which, of course, you should. One of the big lessons is how well thought out the original architecture was. It formed a sturdy base from which modern versions evolved.
There’s been a lot of evolution. The first edition Unix had 2489 lines of kernel code and 9095 lines of programs. That’s even more amazing when you realize that those were lines of assembly code. Today’s FreeBSD distribution has more than 20 million lines of code, mostly in C.
The summary is short and every Unix user should take a look. It’s a reminder about what an astounding achievement Unix is.