Apache: The Definitive Guide, 3rd Edition

Chapter 21. Writing Apache Modules

One of the great things about Apache is that if you don’t like what it does, you can change it. Now, this is actually true for any package with source code available, but Apache makes this easier. It has a generalized interface to modules that extends the functionality of the base package. In fact, when you download Apache, you get far more than just the base package, which is barely capable of serving files at all. You get all the modules the Apache Group considers vital to a web server. You also get modules that are useful enough to most people to be worth the effort of the Group to maintain them. In this chapter, we explore the intricacies of programming modules for Apache.^[1] We expect you to be thoroughly conversant with C and Unix (or Win32), because we are not going to explain anything about them. Refer to Chapter 20 or your Unix/Win32 manuals for information about functions used in the examples. We start out by explaining how to write a module for both Apache 1.3 and 2.0. We also explain how to port a 1.3 module to Apache v2.0.

^[1] For more on Apache modules, see Writing Apache Modules with Perl and C, by Lincoln Stein and Doug MacEachern (O’Reilly, 1999).