Function CGImageSourceCopyMetadataAtIndex 

pub unsafe extern "C-unwind" fn CGImageSourceCopyMetadataAtIndex(
    isrc: &CGImageSource,
    index: usize,
    options: Option<&CFDictionary>,
) -> Option<CFRetained<CGImageMetadata>>

👎Deprecated: renamed to CGImageSource::metadata_at_index

Available on crate features CGImageMetadata and CGImageSource only.