Function xmlSaveDoc 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn xmlSaveDoc(
    ctxt: *mut _xmlSaveCtxt,
    doc: *mut _xmlDoc,
) -> c_long

Serialize doc into the save context’s output buffer.

Returns the number of bytes written, or -1 on error.

SAFETY

• ctxt must be a valid save context.
• doc must be a valid document or NULL.