std::chrono::utc_clock::to_sys
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                    |   template <class Duration> static std::chrono::sys_time<std::common_type_t<Duration, std::chrono::seconds>>  | 
(since C++20) | |
Converts a utc_time t to a sys_time representing the same point in time (if possible).
If t represents a time point during a leap second insertion, the last representable value of sys_time prior to the insertion of the leap second is returned. In all other cases, utc_clock::from_sys(utc_clock::to_sys(t)) == t.
Return value
A sys_time representing the same point in time as t, or the last representable value prior to the insertion of the leap second if t represents a time point during a leap second insertion.
See also
|    [static]  | 
   converts sys_time to utc_time  (public static member function)  | 
|    (C++20)  | 
   convert time points of one clock to another   (function template)  |