std::chrono::system_clock::now

 

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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)

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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::system_clock

Member functions

system_clock::now

system_clock::to_time_t

system_clock::from_time_t

Time point I/O

operator<<

formatter<std::chrono::sys_time>

from_stream

 

static std::chrono::time_point<std::chrono::system_clock> now() noexcept;		(since C++11)

Returns a time point representing the current point in time.

Return value

A time point representing the current time.

Example

Run this code

#include <chrono>
#include <iostream>

int main()
{
    const auto now = std::chrono::system_clock::now();
    const std::time_t t_c = std::chrono::system_clock::to_time_t(now);
    std::cout << "The system clock is currently at " << std::ctime(&t_c);
}

Possible output:

The system clock is currently at Thu Mar 30 13:28:27 2023