std::chrono::system_clock

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C++ Standard Library
Language Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
Utilities library
Date and time utilities
time_point (C++11) duration (C++11) system_clock (C++11) steady_clock (C++11) high_resolution_clock (C++11) C library facilities

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 time, and, therefore, to be displayed.

Contents 1 Member types 2 Member constants 3 Member functions 4 See also

[edit] 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>

[edit] Member constants

is_steady [static]	indicates whether system_clock is steady (public static member constant)

[edit] Member functions

now [static]	returns a 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)

[edit] 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)