Source code tarball now available

I've made some more revisions to the web site of my book. The most notable change is that you can now download the source code for the sample programs. (It's also possible to browse individual program files online here.)

The source code tarball is provided in two versions:

• Distribution version: a version of the source code that includes extra material not shown in the book. Probably, this is the version of the code that you want.
• Book version: the source code as it appears in the book.

The web site explains why there are two versions.

I'd like to hear of any problems that you encounter building (either version of) the code on various Linux systems, especially older distributions. I'll use feedback to build out the source code FAQ.