We'll start with the creation of a very simple extension at first, which basically does nothing more than implement a function that returns the integer it receives as parameter. Esimerkki 30-1 shows the source.
This code contains a complete PHP module. We'll explain the source code in detail shortly, but first we'd like to discuss the build process. (This will allow the impatient to experiment before we dive into API discussions.)
There are basically two ways to compile modules:
The second method is good for those who (for some reason) don't have the full PHP source tree available, don't have access to all files, or just like to juggle with their keyboard. These cases should be extremely rare, but for the sake of completeness we'll also describe this method.
Compiling Using Make. To compile the sample sources using the standard mechanism, copy all their subdirectories to the ext directory of your PHP source tree. Then run buildconf, which will create an updated configure script containing appropriate options for the new extension. By default, all the sample sources are disabled, so you don't have to fear breaking your build process.
After you run buildconf, configure --help shows the following additional modules:
The module shown earlier in Esimerkki 30-1 can be enabled with --enable-first_module or --enable-first_module=yes.
Compiling Manually. To compile your modules manually, you need the following commands:
Note: All include paths in the example are relative to the directory ext. If you're compiling from another directory, change the pathnames accordingly. Required items are the PHP directory, the Zend directory, and (if necessary), the directory in which your module resides.
The link command is also a plain vanilla command instructing linkage as a dynamic module.
You can include optimization options in the compilation command, although these have been omitted in this example (but some are included in the makefile template described in an earlier section).
Note: Compiling and linking manually as a static module into the PHP binary involves very long instructions and thus is not discussed here. (It's not very efficient to type all those commands.)