std::chrono::gps_clock(3)

NAME
std::chrono::gps_clock - std::chrono::gps_clock

Synopsis
   Defined in header <chrono>
   class gps_clock; (since C++20)
   The clock std::chrono::gps_clock is a Clock that represents Global Positioning
   System (GPS) time. It measures time since 00:00:00, 6 January 1980 UTC.
   Leap seconds are not inserted into GPS. Thus, every time a leap second is inserted
   into UTC, UTC falls another second behind GPS. As of December 2017, UTC is 18
   seconds behind GPS, reflecting the 18 leap seconds inserted between 1980 and 2017.
   Thus, 2018-01-01 00:00:00 UTC is equivalent to 2018-01-01 00:00:18 GPS. GPS is a
   constant 19 seconds behind TAI.
   gps_clock meets the Clock requirements. It does not meet the TrivialClock
   requirements unless the implementation can guarantee that now() does not throw an
   exception.

Member types
   Member type Definition
   rep signed arithmetic type representing the number of ticks in the clock's
               duration
   period a std::ratio type representing the tick period of the clock, in seconds
   duration std::chrono::duration<rep, period>, capable of representing negative
               durations
   time_point std::chrono::time_point<std::chrono::gps_clock>

Member constants
                        true if the time between ticks is always constant, i.e.
   constexpr bool is_steady calls to now() return values that increase monotonically
   [static] even in case of some external clock adjustment, otherwise
                        false
                        (public static member constant)

Member functions
   now returns a std::chrono::time_point representing the current point in time
   [static] (public static member function)
   to_utc converts a gps_time to utc_time
   [static] (public static member function)
   from_utc converts a utc_time to gps_time
   [static] (public static member function)