The purpose of this document is to provide fundamental high-level information

about the Mac OS X core operating-system architecture. It also provides

background for system programmers and developers of device drivers, file

systems, and network extensions. In addition, it goes into detail about topics of

interest to kernel programmers as a whole.

This is



not



a document on drivers. It covers device drivers at a high level only. It

does, however, cover some areas of interest to driver writers, such as crossing the

user-kernel boundary. If you are writing device drivers, you should primarily read

the document



Inside Mac OS X: I/O Kit Fundamentals



, but you may still find this

document helpful as background reading.