std::chrono::tai_clock::to_utc
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                    |   template <class Duration> static std::chrono::utc_time<std::common_type_t<Duration, std::chrono::seconds>>  | 
(since C++20) | |
Converts the tai_time t to a utc_time representing the same point in time.
Return value
A std::chrono::utc_time representing the same point in time as t, computed as if by constructing a value of the return type from t.time_since_epoch() and subtracting 378691210s. (378691210 is the number of seconds between the epochs of the two clocks: 1958-01-01 00:00:00 TAI and 1970-01-01 00:00:00 UTC.)
See also
|    [static]  | 
   converts utc_time to tai_time  (public static member function)  | 
|    (C++20)  | 
   convert time points of one clock to another   (function template)  |