std::chrono::utc_clock::from_sys
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std::chrono::utc_clock 
 
 Member functions
utc_clock::from_sys
 Time point I/O
 Leap second insertion information
template< class Duration >
 
 (since C++20) 
static std::chrono::utc_time <std::common_type_t <Duration, std::chrono::seconds >>
Converts a sys_time t to a utc_time u that represents the same point in time.
u.time_since_epoch() - t.time_since_epoch() is equal to the number of leap seconds that was inserted between t and 1 January 1970. If t is the exact date of a leap second insertion, that leap second is counted as inserted.
[edit] Return value
A utc_time representing the same point in time as t.