Mac OS 8 Developer Documentation
Operating System Services
The Notification Manager provides routines that allow software running in the background (or otherwise unseen by the user) to communicate information to the user.
Inside Macintosh: Processes
(Chapter 5 - Notification Manager)
This document describes the parts of the Macintosh system software that allow you to manage processes and tasks.
describes how to use the Notification Manager and includes an overview, a tutorial, and a complete API reference.
Mac OS X