How to know if the app can access the photo album through UIImageWriteToSavedPhotosAlbum with iOS6

Question

I want to know if my app can access the photo album when saving an image to the photo album. When the App is disabled in Privacy settings didFinishSavingWithError returns an error. How to detect if the app is allowed to access the photo album before saving the image?

UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
    if (error != NULL)
    {
        // error        
    }
    else  
    {
        // No errors
    }
}