std::chrono::zoned_time(3)

NAME
std::chrono::zoned_time - std::chrono::zoned_time

Synopsis
   Defined in header <chrono>
   template <
   class Duration, (since C++20)
   class TimeZonePtr = const std::chrono::time_zone*
   > class zoned_time;
   using zoned_seconds = std::chrono::zoned_time<std::chrono::seconds>; (since C++20)
   The class zoned_time represents a logical pairing of a time zone and a
   std::chrono::time_point whose resolution is Duration.
   An invariant of zoned_time is that it always refers to a valid time zone and
   represents an existing and unambiguous time point in that time zone. Consistent with
   this invariant, zoned_time has no move constructor or move assignment operator;
   attempts to move a zoned_time will perform a copy.
   The program is ill-formed if Duration is not a specialization of
   std::chrono::duration.
   The template parameter TimeZonePtr allows users to supply their own time zone
   pointer types and further customize the behavior of zoned_time via
   std::chrono::zoned_traits. Custom time zone types need not support all the
   operations supported by std::chrono::time_zone, only those used by the functions
   actually called on the zoned_time.
   TimeZonePtr must be MoveConstructible. Move-only TimeZonePtrs are allowed but
   difficult to use, as the zoned_time will be immovable and it is not possible to
   access the stored TimeZonePtr.

Member types
   Member type Definition
   duration std::common_type_t<Duration, std::chrono::seconds>

Member functions
   constructor constructs a zoned_time
                       (public member function)
   operator= assigns value to a zoned_time
                       (public member function)
   get_time_zone obtains a copy of the time zone pointer
                       (public member function)
   operator local_time obtains the stored time point as a local_time
   get_local_time (public member function)
   operator sys_time obtains the stored time point as a sys_time
   get_sys_time (public member function)
   get_info obtain information about the time zone at the stored time point
                       (public member function)

Non-member functions
   operator== compares two zoned_time values
   (C++20) (function template)
   operator<< outputs a zoned_time into a stream
   (C++20) (function template)

Helper classes
                        specialization of std::formatter that
   std::formatter<std::chrono::zoned_time> formats a zoned_time according to the
   (C++20) provided format
                        (class template specialization)
  Deduction guides

Example
// Run this code
 #include <chrono>
 #include <iomanip>
 #include <iostream>
 #include <algorithm>
 #include <stdexcept>
 #include <string_view>
 int main()
 {
     constexpr std::string_view locations[] = {
         "Africa/Casablanca", "America/Argentina/Buenos_Aires",
         "America/Barbados", "America/Indiana/Petersburg",
         "America/Tarasco_Bar", "Antarctica/Casey",
         "Antarctica/Vostok", "Asia/Magadan",
         "Asia/Manila", "Asia/Shanghai",
         "Asia/Tokyo", "Atlantic/Bermuda",
         "Australia/Darwin", "Europe/Isle_of_Man",
         "Europe/Laputa", "Indian/Christmas",
         "Indian/Cocos", "Pacific/Galapagos",
     };
     constexpr auto width = std::ranges::max_element(locations, {},
         [](const auto& s) { return s.length(); })->length();
     for (const auto location : locations) {
         try {
             // may throw if `location` is not in the time zone database
             const std::chrono::zoned_time zt{location, std::chrono::system_clock::now()};
             std::cout << std::setw(width) << location << " - Zoned Time: " << zt << '\n';
         } catch (std::chrono::nonexistent_local_time& ex) {
             std::cout << "Error: " << ex.what() << '\n';
         }
     }
 }

Possible output:
              Africa/Casablanca - Zoned Time: 2021-09-16 10:26:54.837665555 +01
 America/Argentina/Buenos_Aires - Zoned Time: 2021-09-16 06:26:55.090150136 -03
               America/Barbados - Zoned Time: 2021-09-16 05:26:55.090419331 AST
     America/Indiana/Petersburg - Zoned Time: 2021-09-16 05:26:55.090465623 EDT
 Error: America/Tarasco_Bar not found in timezone database
               Antarctica/Casey - Zoned Time: 2021-09-16 20:26:55.123070973 +11
              Antarctica/Vostok - Zoned Time: 2021-09-16 15:26:55.123151218 +06
                   Asia/Magadan - Zoned Time: 2021-09-16 20:26:55.123208852 +11
                    Asia/Manila - Zoned Time: 2021-09-16 17:26:55.123434512 PST
                  Asia/Shanghai - Zoned Time: 2021-09-16 17:26:55.123520538 CST
                     Asia/Tokyo - Zoned Time: 2021-09-16 18:26:55.123626199 JST
               Atlantic/Bermuda - Zoned Time: 2021-09-16 06:26:55.123713854 ADT
               Australia/Darwin - Zoned Time: 2021-09-16 18:56:55.155857464 ACST
             Europe/Isle_of_Man - Zoned Time: 2021-09-16 10:26:55.155909304 BST
 Error: Europe/Laputa not found in timezone database
               Indian/Christmas - Zoned Time: 2021-09-16 16:26:55.215065303 +07
                   Indian/Cocos - Zoned Time: 2021-09-16 15:56:55.215137548 +0630
              Pacific/Galapagos - Zoned Time: 2021-09-16 03:26:55.215201447 -06