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- /* This example demonstrates the use of the time zone database and
- * local time to calculate the number of seconds since the UTC
- * time_t epoch 1970-01-01 00:00:00. Note that the selected timezone
- * could be any timezone supported in the time zone database file which
- * can be modified and updated as needed by the user.
- *
- * To solve this problem the following steps are required:
- * 1) Get a timezone from the tz database for the local time
- * 2) Construct a local time using the timezone
- * 3) Construct a posix_time::ptime for the time_t epoch time
- * 4) Convert the local_time to utc and subtract the epoch time
- *
- */
- #include "boost/date_time/local_time/local_time.hpp"
- #include <iostream>
- int main()
- {
- using namespace boost::gregorian;
- using namespace boost::local_time;
- using namespace boost::posix_time;
-
- tz_database tz_db;
- try {
- tz_db.load_from_file("../data/date_time_zonespec.csv");
- }catch(const data_not_accessible& dna) {
- std::cerr << "Error with time zone data file: " << dna.what() << std::endl;
- exit(EXIT_FAILURE);
- }catch(const bad_field_count& bfc) {
- std::cerr << "Error with time zone data file: " << bfc.what() << std::endl;
- exit(EXIT_FAILURE);
- }
- time_zone_ptr nyc_tz = tz_db.time_zone_from_region("America/New_York");
- date in_date(2004,10,04);
- time_duration td(12,14,32);
- // construct with local time value
- // create not-a-date-time if invalid (eg: in dst transition)
- local_date_time nyc_time(in_date,
- td,
- nyc_tz,
- local_date_time::NOT_DATE_TIME_ON_ERROR);
- std::cout << nyc_time << std::endl;
- ptime time_t_epoch(date(1970,1,1));
- std::cout << time_t_epoch << std::endl;
- // first convert nyc_time to utc via the utc_time()
- // call and subtract the ptime.
- time_duration diff = nyc_time.utc_time() - time_t_epoch;
- //Expected 1096906472
- std::cout << "Seconds diff: " << diff.total_seconds() << std::endl;
- }
- /* Copyright 2005: CrystalClear Software, Inc
- * http://www.crystalclearsoftware.com
- *
- * Subject to the Boost Software License, Version 1.0.
- * (See accompanying file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
- */
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