std::chrono::utc_clock

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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

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Defined in header`<chrono>`
class utc_clock;		(since C++20)

The clockstd::chrono::utc_clock is aClock that representsCoordinated Universal Time (UTC). It measures time since 00:00:00 UTC, Thursday, 1 January 1970, including leap seconds.

utc_clock meets theClock requirements. It does not meet theTrivialClock requirements unless the implementation can guarantee thatnow() does not throw an exception.

Time point family

Defined in namespace`std::chrono`
template<class Duration> using utc_time=std::chrono::time_point<std::chrono::utc_clock, Duration>;		(since C++20)
using utc_seconds= utc_time<std::chrono::seconds>;		(since C++20)

operator<<(std::chrono::utc_time) (C++20)	performs stream output on a`utc_time` (function template)[edit]
from_stream(std::chrono::utc_time) (C++20)	parses a`utc_time` from a stream according to the provided format (function template)[edit]
std::formatter<std::chrono::utc_time> (C++20)	formatting support for`utc_time` (class template specialization)[edit]

[edit]Member types

Member type	Definition
`rep`	signed arithmetic type representing the number of ticks in the clock's duration
`period`	astd::ratio type representing the tick period of the clock, in seconds
`duration`	std::chrono::duration<rep, period>, capable of representing negative durations
`time_point`	std::chrono::time_point<std::chrono::utc_clock>

[edit]Member constants

constexpr bool is_steady

[static]

true if the time between ticks is always constant, i.e. calls tonow() return values that increase monotonically even in case of some external clock adjustment, otherwisefalse
(public static member constant)

[edit]Member functions

now [static]	returns astd::chrono::time_point representing the current point in time (public static member function)[edit]
to_sys [static]	converts`utc_time` to`sys_time` (public static member function)[edit]
from_sys [static]	converts`sys_time` to`utc_time` (public static member function)[edit]