pub unsafe extern "C" fn FLAC__metadata_iterator_insert_block_before(
iterator: *mut FLAC__Metadata_Iterator,
block: *mut FLAC__StreamMetadata
) -> FLAC__bool
pub unsafe extern "C" fn FLAC__metadata_iterator_insert_block_before(
iterator: *mut FLAC__Metadata_Iterator,
block: *mut FLAC__StreamMetadata
) -> FLAC__bool