Get Display Brightness

Question

Is there a way to get the display brightness in OS X 10.9+ now that CGDisplayIOServicePort has been deprecated?

Answer 1

After some searching and fiddling around, here is a "future proof" way to get the brightness of the display that doesn't use the CGDisplayIOServicePort deprecated in OS X 10.9.

- (float)getDisplayBrightness
{
    float brightness = 1.0f;
    io_iterator_t iterator;
    kern_return_t result = 
        IOServiceGetMatchingServices(kIOMasterPortDefault,
            IOServiceMatching("IODisplayConnect"),
            &iterator);

    // If we were successful
    if (result == kIOReturnSuccess)
    {
        io_object_t service;

        while ((service = IOIteratorNext(iterator)))
        {
            IODisplayGetFloatParameter(service, 
                kNilOptions, 
                CFSTR(kIODisplayBrightnessKey), 
                &brightness);

            // Let the object go
            IOObjectRelease(service);
        }
    }

    return brightness;
}