std::chrono::time_zone::to_local

 

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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)

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_zone

Member functions

time_zone::name

time_zone::get_info

time_zone::to_sys

time_zone::to_local

Nonmember functions

operator==operator<=>

 

template< class Duration > auto to_local( const std::chrono::sys_time<Duration>& tp ) const -> std::chrono::local_time<std::common_type_t<Duration, std::chrono::seconds>>;		(since C++20)

Converts the sys_time tp to the corresponding local_time in this time zone.

Parameters

tp

-

a time point to be converted

Return value

The local_time associated with tp and this time zone.

Notes

The precision of the result is at least std::chrono::seconds, and will be finer if the argument has finer precision.

Example

Run this code

#include <chrono>
#include <iostream>

int main()
{
    const auto some_zone_name{"Australia/Sydney"};
    const auto time_pt_utc{std::chrono::system_clock::now()};
    std::cout << "Current time UTC is:\t\t " << time_pt_utc << '\n';

    try
    {
        std::cout << "Current time local is:\t\t "
                  << std::chrono::current_zone()-> // may throw
                      to_local(time_pt_utc) << '\n'
                  << "Current time " << some_zone_name << " is:\t "
                  << std::chrono::locate_zone(some_zone_name)-> // may throw
                      to_local(time_pt_utc) << '\n';
    }
    catch(const std::runtime_error& ex)
    {
        std::cout << ex.what() << '\n';
    }
}

Possible output:

Current time UTC is:              2025-02-10 13:38:13.233872158
Current time local is:            2025-02-10 16:38:13.233872158
Current time Australia/Sydney is: 2025-02-11 00:38:13.233872158