* "flags", any badly-encoded chars are included verbatim in the "out" xbuf,
* so EILSEQ will not be returned. Likewise for ICB_INCLUDE_INCOMPLETE with
* respect to an incomplete multi-byte char at the end, which ensures that
* "flags", any badly-encoded chars are included verbatim in the "out" xbuf,
* so EILSEQ will not be returned. Likewise for ICB_INCLUDE_INCOMPLETE with
* respect to an incomplete multi-byte char at the end, which ensures that