extern wchar_t * asnwprintf (wchar_t *resultbuf, size_t *lengthp, const wchar_t *format, ...);
extern wchar_t * vasnwprintf (wchar_t *resultbuf, size_t *lengthp, const wchar_t *format, va_list args);
extern wchar_t * asnwprintf (wchar_t *resultbuf, size_t *lengthp, const wchar_t *format, ...);
extern wchar_t * vasnwprintf (wchar_t *resultbuf, size_t *lengthp, const wchar_t *format, va_list args);