Inside Macintosh: Macintosh Toolbox Essentials
The GetSpecificHighLevelEvent function (GetSpecificHighLevelEvent) takes a universal procedure pointer to an application-defined filter function used to search for a specific event. The Event Manager declares the type for an application-defined specific event filter function as follows:
typedef pascal Boolean (*GetSpecificFilterProcPtr)
(void *contextPtr,
HighLevelEventMsgPtr msgBuff,
const TargetID *sender);
For information about writing a specific filter function, see "Filter Function for Searching the High-Level Event Queue" .
The Event Manager defines the universal procedure pointer GetSpecificFilterUPP for an application-defined filter function.
typedef UniversalProcPtr GetSpecificFilterUPP;
The Event Manager also defines the macro NewGetSpecificFilterProc for obtaining a GetSpecificFilterUPP :
#define NewGetSpecificFilterProc(userRoutine)\(GetSpecificFilterUPP)
NewRoutineDescriptor((ProcPtr)(userRoutine),
uppGetSpecificFilterProcInfo, GetCurrentArchitecture())
You typically use the NewGetSpecificFilterProc macro like this:
GetSpecificFilterUPP myFilterFunctionProc;
myFilterFunctionProc = NewGetSpecificFilterProc(MyFilter);
The Event Manager also defines the macro CallGetSpecificFilterProc for calling a GetSpecificFilterUPP . You normally don't need to call this macro directly:
#define CallGetSpecificFilterProc(userRoutine, contextPtr,
msgBuff, sender)\
CallUniversalProc((UniversalProcPtr)(userRoutine),
uppGetSpecificFilterProcInfo, (contextPtr), (msgBuff), (sender))
For more information about universal procedure pointers and the Mixed Mode Manager, see Inside Macintosh: PowerPC System Software.