Estou tentando obter eventos de toque no meu aplicativo. Então eu usei o retorno de chamada IOHIDFamily para obter os eventos. Meu código é assim:

void handle_event(void* target, void* refcon, IOHIDServiceRef service, IOHIDEventRef event)
{
    printf("Received event of type %2d from service %p.\n", 
           IOHIDEventGetType(event), service);
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    void *ioHIDEventSystem = IOHIDEventSystemClientCreate(kCFAllocatorDefault);
    IOHIDEventSystemClientScheduleWithRunLoop(system, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
    IOHIDEventSystemClientRegisterEventCallback(system, handle_event, NULL, NULL);
    CFRunLoopRun();
}

Eu recebi um erro ao executar:

IOHIDEventSystemClientScheduleWithRunLoop (system, CFRunLoopGetCurrent (), kCFRunLoopDefaultMode);

IOKit`IOHIDEventSystemClientScheduleWithRunLoop:
...
0x32f8fd14: cmp.w r10, nº 0
0x32f8fd18: strd r10, r11, [r4, # 116] <--- EXC_BAD_ACCESS (código = EXC_ARM_DA_ALIGN)
0x32f8fd1c: beq 0x32f8fdac; IOHIDEventSystemClientScheduleWithRunLoop + 168
0x32f8fd1e: ldr r1, [r4, # 96]
0x32f8fd20: cbz r1, 0x32f8fd2a; IOHIDEventSystemClientScheduleWithRunLoop + 38
0x32f8fd22: mov r0, r10
...

Eu usei IOHIDFamily no caminho errado?