Function xmlTextReaderIsValid 

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

Return the validation status of the reader.

UPSTREAM-PARITY

Upstream xmlTextReaderIsValid (xmlreader.c): with a RELAX NG validation context attached the RELAX NG outcome wins, then the XSD outcome, then the DTD-parse validity (ctxt->valid); 0 when no validation was performed or it failed, -1 for a NULL reader.

int xmlTextReaderIsValid(xmlTextReaderPtr reader);

Safety

reader must be a valid pointer or NULL.