_itowa
wnumstr = _itowa (num, \
extern wchar_t *_itowa (unsigned long long int value, wchar_t *buflim,
wnumstr = _itowa (num, wnumbuf + sizeof wnumbuf / sizeof (wchar_t), 16,
# define _itoa(Val, Buf, Base, Case) _itowa (Val, Buf, Base, Case)