Inside Macintosh: Operating System Utilities /

Chapter 1 - Gestalt Manager / Gestalt Manager Reference

Gestalt Manager Routines

This section describes the three Gestalt Manager functions, Gestalt, NewGestalt, and ReplaceGestalt. It also describes the SysEnvirons function, which can give you a brief description of the operating environment when Gestalt is not available. The Gestalt Manager functions allow you to

• find out what hardware and software features are present
• add new selectors to those understood by the Gestalt function
• replace the functions associated with known selectors

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Subtopics

Getting Information About the Operating Environment

Adding a Selector Code

Modifying a Selector Function