Chapter 17: Using Classic

Overview

In the world of OS X, Classic is what is referred to as an application environment. Apple developed Classic as a means to permit Macintosh users to run software that is not capable of running natively in Mac OS X as a Carbon or Cocoa application (see Chapter One for more information on the Carbon and Cocoa application environments). What’s good about Classic is that you will be able to run most of your old software. Because the Classic application environment itself runs on top of Mac OS X, if a Classic application crashes, the Classic environment can be restarted without rebooting your computer. The downsides of Classic are that Classic applications don’t take advantage of Mac OS X’s modern OS features and Classic applications generally do not have extensive hardware support.

So, who needs Classic? It is important to look at Classic as little more than a convenient stopgap to run your old programs while you transition to Mac OS X. The benefits of upgrading your applications to native versions abound: advanced memory management, protected memory space, true multitasking, and symmetric multiprocessing, to name but a few. With Mac OS 10.3’s release, just about every major application has been updated to run natively. However, in the event that one of your applications isn’t updated, or you just need to run an old version in an emergency and your Mac does not support Mac OS 9 booting, you will have to rely on Classic.

This Chapter is meant to familiarize you with the ins and outs of the Classic application environment — what it is, when and why you would need to use it, and how to configure it from a general standpoint.