Important: The information in this document is obsolete and should not be used for new development.
Before calling any functions dependent on the Window Manager, your application should pass the selector gestaltWindowMgrAttr to the Gestalt function to determine which Window Manager functions are available.
enum {
gestaltWindowMgrAttr = 'wind',
gestaltWindowMgrPresent = (1L << 0),
gestaltHasFloatingWindows = 2
};