One of PHP5's most interesting new features is the addition of Iterators, a collection of ready-made interfaces designed to help in navigating and processing hierarchical data structures. These Iterators significantly reduce the amount of code required to process an XML document tree or a file collection.

They give three examples - two basic ones showing a simple use of the DirectoryIterator and RecursiveDirectoryIterator and another slightly more complex one showing how to get information from the recursive iteration as it goes down.

Given a directory, the test runner will recursively scan the directory for *Test.php files, build a test suite out of the *Test classes, and run it.

PHPUnit is framework that makes writing tests for your code easy and also includes functionality to run the tests and analyze their results.

In PHP 5.3 there will be another magic constant __DIR__. [...] To allow this, the internal function php_dirname() has been moved in the Zend Engine and is now called zend_dirname(). Nevertheless an alias still exists.

__DIR__ will join the other constants (like __LINE__ and __FUNCTION__) to help give the currently running script a little introspection for things like its filename, what class it's currently in and now, what directory the file currently lives in.

I downloaded Apache 2.2.6, PHP 5.2.4 and MySQL 5.0.45. I compiled and installed them and finally added a few virtual hosts. None of the vhosts worked. They all gave me [an error]. I had missed that apache now ships with a slightly different configuration for the / directory

He includes the fix for this, what he thinks is a better way to handle it - setting the Directory value to only the directory Apache needs to allow.