Identifying Preemptively Safe System Calls

Header: Gestalt.h

enum {
    gestaltMPCallableAPIsAttr = ''mpsc'',
    gestaltMPFileManager = ,
    gestaltMPDeviceManager = 1
};

Constant descriptions

gestaltMPCallableAPIsAttr: The Gestalt selector passed to determine the availability of preemptive system software functions. The Gestalt function produces a 32-bit value that you should test to determine which what type of preemptive calls are allowed.
gestaltMPFileManager: If this bit is set, you can call preemptively safe File Manager functions.
gestaltMPDeviceManager: If this bit is set, you can call preemptively safe Device Manager function.

Before calling any Mac OS system software functions from a preemptive task , you should call the Gestalt function with the gestaltMPCallableAPIsAttr selector set to determine which preemptively safe system calls are allowed.

Note that for functions that are shared between managers (for example, PBCloseSync), you should check the bit that is appropriate for the manager you want to call.

VERSION NOTES

Introduced with Multiprocessing Services 2.1