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	std::chrono::time_point<std::chrono::system_clock>

Member constants

bool is_steady [static]	true if the time between ticks is always constant, i.e. calls to now() return values that increase monotonically even in case of some external clock adjustment (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)