< cpp‎ | chrono
Revision as of 12:52, 5 August 2013 by (Talk)

Defined in header <chrono>

    class Clock,
    class Duration = typename Clock::duration

> class time_point;
(since C++11)

Class template std::chrono::time_point represents a point in time. It is implemented as if it stores a value of type Duration indicating the time interval from the start of the Clock's epoch.


Member types

Member type Definition
clock Clock, the clock on which this time point is measured
duration Duration, a std::chrono::duration type used to measure the time since epoch
rep Rep, an arithmetic type representing the number of ticks of the duration
period Period, a std::ratio type representing the tick period of the duration

Member functions

constructs a new time point
(public member function) [edit]
returns the time point as duration since the start of its clock
(public member function) [edit]
modifies the time point by the given duration
(public member function) [edit]
returns the time point corresponding to the smallest duration
(public static member function) [edit]
returns the time point corresponding to the largest duration
(public static member function) [edit]

Non-member functions

specializes the std::common_type trait
(class template specialization) [edit]
modifies the time point by the given duration
(function template) [edit]
compares two time points
(function template) [edit]
converts a time point to another time point on the same clock, with a different duration
(function template) [edit]


This example prints the current time minus 24 hours:

#include <iostream>
#include <iomanip>
#include <ctime>
#include <chrono>
int main()
    using namespace std::chrono;
    system_clock::time_point now = system_clock::now();
    std::time_t now_c = system_clock::to_time_t(
                            now - std::chrono::hours(24));
    std::cout << "One day ago, the time was "
              << std::put_time(std::localtime(&now_c), "%F %T") << '\n';

Possible output:

One day ago, the time was 2011-10-25 12:00:08

This example prints the time it takes to print "Hello World":

#include <iostream>
#include <chrono>
using std::chrono::duration_cast;
using std::chrono::microseconds;
using std::chrono::steady_clock;
int main()
    steady_clock::time_point start = steady_clock::now();
    std::cout << "Hello World\n";
    steady_clock::time_point end = steady_clock::now();
    std::cout << "Printing took "
              // duration_cast is required to avoid accidentally losing precision.
              << duration_cast<microseconds>(end - start).count()
              << "us.\n";

Possible output:

Hello World
Printing took 84us.

See also

a time interval
(class template)