What to do if we want convert time between two timezones?
For example, an event occured at 15-00 by Moscow time(UTC+4). By that time, in Omsk(UTC+7) there is 18-00, three hours "more". We want to show time of event using local Omsk time.
How to do that in C++?
Fill tmDateExternal structure of type tm, with source event time(15-00). Save timezone shift of Moscow to in nSrcTZ, it is obviously 4.
Now you have local Omsk time for that event in tmDateLocal structure.
For example, an event occured at 15-00 by Moscow time(UTC+4). By that time, in Omsk(UTC+7) there is 18-00, three hours "more". We want to show time of event using local Omsk time.
How to do that in C++?
Fill tmDateExternal structure of type tm, with source event time(15-00). Save timezone shift of Moscow to in nSrcTZ, it is obviously 4.
__time64_t t64date = _mkgmtime64(&tmDateExternal) - nSrcTZ*60*60; tm tmDateLocal; _localtime64_s( &tmDateLocal, &t64date );
Now you have local Omsk time for that event in tmDateLocal structure.
