NX_KEYTYPE_BRIGHTNESS_UP/DOWN does't work

Hi,

I'm improving my app that simulates hardware keyboard and trackpad and want to add function keys like volume up/down and etc.

All the media keys are working fine (NX_KEYTYPE_SOUND_UP for example) but NX_KEYTYPE_BRIGHTNESS_UP/DOWN does't work.

Here the code I found that sends those keyboard events:

/
/
static io_connect_t _getAuxiliaryKeyDriver(void)
{
    static mach_port_t sEventDrvrRef = 0;
    mach_port_t masterPort, service, iter;
    kern_return_t kr;
   
    if (!sEventDrvrRef)
    {
        kr = IOMasterPort( bootstrap_port, &masterPort );
        assert(KERN_SUCCESS == kr);
       
        kr = IOServiceGetMatchingServices(masterPort, IOServiceMatching( kIOHIDSystemClass), &iter );
        assert(KERN_SUCCESS == kr);
       
        service = IOIteratorNext( iter );
        assert(service);
       
        kr = IOServiceOpen(service, mach_task_self(), kIOHIDParamConnectType, &sEventDrvrRef );
        assert(KERN_SUCCESS == kr);
       
        IOObjectRelease(service);
        IOObjectRelease(iter);
    }
    return sEventDrvrRef;
}
/
/
static void _postAuxiliaryKey(const UInt8 auxKeyCode)
{
    NXEventData   event;
    kern_return_t kr;
    IOGPoint loc = { 0, 0 };
   
   
    /
    UInt32 evtInfo = auxKeyCode << 16 | NX_KEYDOWN << 8;
    bzero(&event, sizeof(NXEventData));
    event.compound.subType = NX_SUBTYPE_AUX_CONTROL_BUTTONS;
    event.compound.misc.L[0] = evtInfo;
    kr = IOHIDPostEvent( _getAuxiliaryKeyDriver(), NX_SYSDEFINED, loc, &event, kNXEventDataVersion, 0, FALSE );
    assert( KERN_SUCCESS == kr );
   
    /
    evtInfo = auxKeyCode << 16 | NX_KEYUP << 8;
    bzero(&event, sizeof(NXEventData));
    event.compound.subType = NX_SUBTYPE_AUX_CONTROL_BUTTONS;
    event.compound.misc.L[0] = evtInfo;
    kr = IOHIDPostEvent( _getAuxiliaryKeyDriver(), NX_SYSDEFINED, loc, &event, kNXEventDataVersion, 0, FALSE );
    assert( KERN_SUCCESS == kr );
   
}

What so special about brigthness? (it does work when I change it using my hardware keyboard).

Thanks.