25 Time library [time]

25.7 Clocks [time.clock]

25.7.9 time_­point conversions [time.clock.cast]

25.7.9.3 Conversions between system_­clock and utc_­clock [time.clock.cast.sys.utc]

template<>
struct clock_time_conversion<utc_clock, system_clock> {
  template<class Duration>
    utc_time<common_type_t<Duration, seconds>>
      operator()(const sys_time<Duration>& t) const;
};
template<class Duration> utc_time<common_type_t<Duration, seconds>> operator()(const sys_time<Duration>& t) const;
Returns: utc_­clock::from_­sys(t).
template<>
struct clock_time_conversion<system_clock, utc_clock> {
  template<class Duration>
    sys_time<common_type_t<Duration, seconds>>
      operator()(const utc_time<Duration>& t) const;
};
template<class Duration> sys_time<common_type_t<Duration, seconds>> operator()(const utc_time<Duration>& t) const;
Returns: utc_­clock::to_­sys(t).