PHPit.net has another beginner-level tutorial posted on its site today - this time, with a low level look at some of the file functions that PHP has to offer.

Welcome to this beginner's introduction to PHP's file functions. In this article I will take you through all the inbuilt filesystem functions, and explain them. This article is mainly geared towards beginners, but it could still be useful to more advanced developers as a simple refresher.

This article will show you how to do the following things: reading files (using several different methods), writing files, copying files, deleting files, getting file properties (like last modified time, last access time, etc), checking file permissions, reading directories, and more!

The article touches on all of the major ones including explainations all along the way. There's plenty of code examples that are simple and to the point as well...