The installation instructions in this chapter refer to PHP version 5.0.2, which is the current version of the software.
By the Way
If you are already using PHP 4.3.x in a production environment, or you wish to stay with the 4.3.x development tree until version 5.0.x has more release time under its belt, the installation is almost exactly the same. Just substitute the appropriate file name where applicable, and look for other notes regarding the difference between versions.
The PHP Group uses minor release numbers for updates containing security enhancements or bug fixes. Minor releases do not follow a set release schedule; when enhancements or fixes are added to the code and thoroughly tested, the PHP Group will release a new version, with a new minor version number.
It is possible that by the time you purchase this book, the minor version number will have changed, to 5.0.3 or beyond. If that is the case, you should read the list of changes at http://www.php.net/ChangeLog-5.php for any changes regarding the installation or configuration process, which makes up the bulk of this chapter.
Although it is unlikely that any installation instructions will change between minor version updates, you should get in the habit of always checking the changelog of software that you install and maintain. If a minor version change does occur during the time you are reading this book, but no installation changes are noted in the changelog, simply make a mental note and substitute the new version number wherever it appears in the installation instructions and accompanying figures.