std::time_get::do_get

public:
iter_type get(iter_type beg, iter_type end, std::ios_base& str,
              std::ios_base::iostate& err, std::tm* t,
              const char_type* fmtbeg, const char_type* fmtend) const;

protected:
virtual iter_type do_get(iter_type neg, iter_type end, std::ios_base& str,
                         std::ios_base::iostate& err, std::tm *t,
                         char format, char modifier) const;