Function CMMetadataCreateKeyFromIdentifierAsCFData 

pub unsafe extern "C-unwind" fn CMMetadataCreateKeyFromIdentifierAsCFData(
    allocator: Option<&CFAllocator>,
    identifier: &CFString,
    key_out: NonNull<*const CFData>,
) -> i32

Available on crate feature CMMetadata only.

Creates a copy of the key value that was encoded in the identifier as CFData. The bytes in the CFData correpsond to how they are serialized in the file.

Safety

key_out must be a valid pointer.