std::chrono::utc_clock::to_sys

C++

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Language support library

Concepts library (C++20)

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Regular expressions library (C++11)

Atomic operations library (C++11)

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Filesystem library (C++17)

Technical Specifications

Utilities library

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strong_order weak_order partial_order strong_equal weak_equal	strong_ordering weak_ordering partial_ordering strong_equality weak_equality	is_eqis_neqis_ltis_lteqis_gtis_gteq
common_comparison_category
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Date and time utilities

duration (C++11) time_point (C++11) time_of_day (C++20)	clock_time_conversion (C++20) clock_cast (C++20)
Clocks
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Calendars
day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20) year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)	weekday_indexed (C++20) weekday_last (C++20) month_day (C++20) month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20)
Time zones
tzdb (C++20) tzdb_list (C++20) get_tzdbget_tzdb_listreload_tzdbremote_version (C++20)(C++20)(C++20)(C++20)	time_zone (C++20) locate_zone (C++20) current_zone (C++20) zoned_time (C++20) link (C++20) leap (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<<

to_stream

from_stream

template <class Duration> static std::chrono::sys_time<std::common_type_t<Duration, std::chrono::seconds>> to_sys(const std::chrono::utc_time<Duration>& t);		(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

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