std::chrono::utc_clock::from_sys

 

C++

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Date and time utilities

Time point
time_point (C++11)	clock_time_conversion (C++20)	clock_cast (C++20)
Duration
duration (C++11)
Clocks
system_clock (C++11) steady_clock (C++11) is_clock (C++20)	utc_clock (C++20) tai_clock (C++20) high_resolution_clock (C++11)	gps_clock (C++20) file_clock (C++20) local_t (C++20)
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chrono I/O
parse (C++20)
C-style date and time

 

std::chrono::utc_clock

Member functions

utc_clock::now

utc_clock::to_sys

utc_clock::from_sys

Time point I/O

operator<<

formatter<std::chrono::utc_time>

from_stream

Leap second insertion information

leap_second_info

get_leap_second_info

 

template< class Duration > static std::chrono::utc_time<std::common_type_t<Duration, std::chrono::seconds>>     from_sys( const std::chrono::sys_time<Duration>& t );		(since C++20)

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.

Return value

A utc_time representing the same point in time as t.

See also

to_sys [static]	converts utc_time to sys_time (public static member function)
clock_cast (C++20)	convert time points of one clock to another (function template)