iter_type do_put(iter_type s, bool intl, ios_base& str,
char_type fill, long double units) const;
iter_type do_put(iter_type s, bool intl, ios_base& str,
char_type fill, const string_type& digits) const;
ct.widen(buf1, buf1 + sprintf(buf1, "%.0Lf", units), buf2)for character buffers buf1 and buf2.