std::chrono::system_clock

 

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std::chrono::system_clock

Member functions

system_clock::now

system_clock::to_time_t

system_clock::from_time_t

 

Defined in header <chrono>
class system_clock;		(since C++11)

Class std::chrono::system_clock represents the system-wide real time wall clock.

It may not be monotonic: on most systems, the system time can be adjusted at any moment. It is the only C++ clock that has the ability to map its time points to C-style time, and, therefore, to be displayed.

std::chrono::system_clock meets the requirements of TrivialClock.

Member types

Member type	Definition
rep	signed arithmetic type representing the number of ticks in the clock's duration
period	an std::ratio type representing the tick period of the clock, in seconds
duration	std::chrono::duration<rep, period>, capable of representing negative durations
time_point	the type of this clock's time point, std::chrono::time_point<system_clock>

Member constants

bool is_steady [static]	true if the time between ticks is constant and calls to now return values that increase monotonically (public static member constant)

Member functions

now [static]	returns a std::chrono::time_point representing the current point in time (public static member function)
to_time_t [static]	converts a system clock time point to std::time_t (public static member function)
from_time_t [static]	converts std::time_t to a system clock time point (public static member function)

See also

steady_clock (C++11)	monotonic clock that will never be adjusted (class)
high_resolution_clock (C++11)	the clock with the shortest tick period available (class)