Function xmlTextReaderSetStructuredErrorHandler 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn xmlTextReaderSetStructuredErrorHandler(
    reader: *mut XmlTextReader,
    f: Option<xmlStructuredErrorFunc>,
    arg: *mut c_void,
)

void xmlTextReaderSetStructuredErrorHandler(xmlTextReaderPtr reader, xmlStructuredErrorFunc f, void *arg).

SAFETY

• reader, arg must be valid pointers (or NULL where the upstream C contract allows), obtained from the matching constructor/owner and not yet freed; the callee may take or keep ownership exactly as the C API specifies.

• f must be a valid callback (or None); the callback is invoked with the documented context pointer and must itself uphold the same pointer invariants.

The caller must not race this call with concurrent mutation of the same objects from other threads (per-object state is not internally synchronized). Violating any of the above is undefined behavior.

Exercised by the C-API differential courts (courts/suites/data-abi/*-family-probe.c) and the CLI differential courts; those pass byte-for-byte against the upstream oracle.