Date in another Timezone: C++ on Linux

Question

Is there any way of getting the date...preferably in YYYYMMDD format...in the Australia/Sydney timezone (not just GMT+11).....through C++ on Linux?

Thanks,

Roger

Answer 1

Yes, but you just use the standard c library mechanisms.

set the desired time zone in the environment by creating a string:

std::string tz = "Australia/Sydney";
setenv("TX", const_cast<char *>(tz.c_str()), 1);
tzset(); // Initialize timezone data
time_t aTime = time(NULL); // get the time - this is GMT based.
struct tm retTime;
localtime_r(&aTime, &retTime); // Convert time into current timezone.
char destString[1024];
strftime(destString, 1023, "%Y%m%d %Z", &retTime); // Format the output in the local time.
std::cout << destString << std::endl;

The problem is that this code is not thread safe - multiple threads changing the timezone information does not end well.

This Answer Gives you a way to do it using boost, which is definitely much easier.