Function xsltSaveResultToString 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn xsltSaveResultToString(
    doc_txt_ptr: *mut *mut xmlChar,
    doc_txt_len: *mut c_int,
    result: *mut _xmlDoc,
    style: *mut _xsltStylesheet,
) -> c_int

Save a result document to a buffer, honoring output settings.

Returns a newly allocated string in doc_txt_ptr and its length in doc_txt_len. Returns 0 on success, -1 on error.

UPSTREAM-PARITY

Mirrors xsltSaveResultToString (xsltutils.c 1.1.45): the output is the serialized document converted to the stylesheet’s output encoding (UTF-8 when no encoding or a UTF-8 encoding is selected). Note that upstream does not validate style here; xsltSaveResultTo fails for a NULL stylesheet and yields an empty string.

SAFETY

• doc_txt_ptr and doc_txt_len must be valid non-null pointers.
• result must be a valid document.
• style must be a valid stylesheet (or NULL for empty output).