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Modifying Your Application to Use 64-Bit Addressing

This chapter explains what kinds of modifications are needed in existing Carbon applications to make them compile and run as 64-bit executables.

Mac OS X v10.5 (Leopard) provides two different implementations of its programming interfaces: one for 32-bit applications and another for 64-bit applications. You may choose to build your application using either one or both of these implementations. Some Leopard header files have been modified to support both implementations, and these header files often select or remove code for 64-bit compilation.

For 32-bit applications, Apple’s goal is to maintain complete source compatibility; when recompiled on Leopard, 32-bit applications should not need to change their sources to compile against Leopard headers. If you find instances where changes to the Leopard headers have broken the compilation of your 32-bit application, you should treat these as bugs and report them to Apple.

If you plan to modify your application to use 64-bit addressing, you may need to adopt standard data types that can be used identically in both 32-bit and 64-bit applications. You also need to be aware that the APIs used to implement a Carbon user interface—menus, windows, views, toolbars, navigation dialogs, and so on—are generally not available. If you want to create a 64-bit application, you need to use Cocoa to implement its user interface.

Later in this document, you’ll learn more about replacement alternatives for the APIs and technologies that aren’t available to 64-bit applications.

Contents:

Conditional Compilation
Standard Types
What’s Not Available to 64-Bit Applications
Choosing a Development Path for Your Carbon User Interface

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