Function dds_stream_getsize_key 

pub unsafe extern "C" fn dds_stream_getsize_key(
    sample: *const c_char,
    desc: *const dds_cdrstream_desc,
    xcdr_version: dds_cdr_enc_version,
) -> usize

@brief Compute the serialized size of a sample key. @component cdr_serializer

@param sample sample containing key fields @param desc CDR stream descriptor for the sample type @param xcdr_version XCDR version to size for @returns serialized key size in bytes, or SIZE_MAX on error