If wc is a wide character, the towctrans function translates it according to the transliteration descriptor desc. If wc is WEOF, WEOF is returned.
desc must be a transliteration descriptor returned by the wctrans function.
The towctrans function returns the translated wide character, or WEOF if wc is WEOF.
ISO/ANSI C, UNIX98
wctrans(3), towlower(3), towupper(3)