std::chrono::time_point<Clock,Duration>::time_point

 

C++

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Symbols index

External libraries

 

Date and time library

Time point time_point (C++11) clock_time_conversion (C++20)   clock_cast (C++20) Duration duration (C++11) Clocks system_clock (C++11) steady_clock (C++11) is_clock (C++20) utc_clock (C++20) tai_clock (C++20) high_resolution_clock (C++11) gps_clock (C++20) file_clock (C++20) local_t (C++20) Time of day is_amis_pm (C++20)(C++20) make12make24 (C++20)(C++20) hh_mm_ss (C++20)

Calendar day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20) year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)   weekday_indexed (C++20) weekday_last (C++20) month_day (C++20) month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20) last_speclast (C++20)(C++20) chrono I/O parse (C++20)

Time zone tzdb (C++20) tzdb_list (C++20) get_tzdbget_tzdb_listreload_tzdbremote_version (C++20)(C++20)(C++20)(C++20) sys_info (C++20) local_info (C++20) nonexistent_local_time (C++20) ambiguous_local_time (C++20) locate_zone (C++20) current_zone (C++20) time_zone (C++20) choose (C++20) zoned_traits (C++20) zoned_time (C++20) time_zone_link (C++20) leap_second (C++20) leap_second_info (C++20) get_leap_second_info (C++20) C-style date and time

 

std::chrono::time_point

Member functions

time_point::time_point

time_point::time_since_epoch

time_point::operator+=time_point::operator-=

time_point::operator++time_point::operator-- (C++20)(C++20)

time_point::min

time_point::max

Non-member functions

operator+operator-

operator==operator!=operator<operator<=operator>operator>=operator<=> (until C++20)(C++20)

time_point_cast

floor (C++17)

ceil (C++17)

round (C++17)

Helper classes

common_type

hash<std::chrono::time_point> (C++26)

 

time_point();	(1)	(since C++11) (constexpr since C++14)
explicit time_point( const duration& d );	(2)	(since C++11) (constexpr since C++14)
template< class Duration2 > time_point( const time_point<Clock, Duration2>& t );	(3)	(since C++11) (constexpr since C++14)

Constructs a new time_point from one of several optional data sources.

1) Default constructor, creates a time_point representing the Clock's epoch (i.e., time_since_epoch() is zero).

2) Constructs a time_point at Clock's epoch plus d.

3) Constructs a time_point by converting t to duration. This constructor only participates in overload resolution if Duration2 is implicitly convertible to duration.

Parameters

d	-	a duration to copy from
t	-	a time_point to convert from

Example

Run this code

#include <chrono>
#include <iostream>

using Clock = std::chrono::steady_clock;
using TimePoint = std::chrono::time_point<Clock>;

void print_ms(const TimePoint& point)
{
    using Ms = std::chrono::milliseconds;
    const Clock::duration since_epoch = point.time_since_epoch();
    std::cout << std::chrono::duration_cast<Ms>(since_epoch) << '\n';
}

int main()
{
    const TimePoint default_value = TimePoint(); // (1)
    print_ms(default_value); // 0ms

    const Clock::duration duration_4_seconds = std::chrono::seconds(4);
    const TimePoint time_point_4_seconds(duration_4_seconds); // (2)
    // 4 seconds from start of epoch
    print_ms(time_point_4_seconds); // 4000ms

    const TimePoint time_point_now = Clock::now(); // (3)
    print_ms(time_point_now); // 212178842ms
}

Possible output:

0ms
4000ms
212178842ms

See also

(constructor)	constructs new duration (public member function of std::chrono::duration<Rep,Period>)
duration_cast (C++11)	converts a duration to another, with a different tick interval (function template)