Function xmlTextReaderIsDefault 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn xmlTextReaderIsDefault(
    reader: *mut XmlTextReader,
) -> c_int

int xmlTextReaderIsDefault(xmlTextReaderPtr reader) — whether the current attribute came from the DTD default. The candidate returns 0 for a valid reader (DTD default attribute expansion is not annotated; documented divergence), -1 for a NULL reader (upstream contract).