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How to convert between time zones using win32 API?

I have date strings like AEDST and want to convert them to a SYSTEMTIME structure. So far, I:

SYSTEMTIME st;
FILETIME ft;
SecureZeroMemory(&st, sizeof(st));
sscanf_s(contents, "%u-%u-%u %u:%u:%u",
    &st.wYear,
    &st.wMonth,
    &st.wDay,
    &st.wHour,
    &st.wMinute,
    &st.wSecond);
// Timezone correction
SystemTimeToFileTime(&st,  &ft);
LocalFileTimeToFileTime(&ft, &ft);
FileTimeToSystemTime(&ft, &st);

However, my local time zone is not AEDST. Therefore, I need to specify the time zone when converting to UTC.

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2 answers

Take a look at this:

https://web.archive.org/web/20140205072348/http://weseetips.com:80/2008/05/28/how-to-convert-local-system-time-to-utc-or-gmt/

 // Get the local system time.
 SYSTEMTIME LocalTime = { 0 };
 GetSystemTime( &LocalTime );

 // Get the timezone info.
 TIME_ZONE_INFORMATION TimeZoneInfo;
 GetTimeZoneInformation( &TimeZoneInfo );

 // Convert local time to UTC.
 SYSTEMTIME GmtTime = { 0 };
 TzSpecificLocalTimeToSystemTime( &TimeZoneInfo,
                                  &LocalTime,
                                  &GmtTime );

 // GMT = LocalTime + TimeZoneInfo.Bias
 // TimeZoneInfo.Bias is the difference between local time
 // and GMT in minutes. 

 // Local time expressed in terms of GMT bias.
 float TimeZoneDifference = -( float(TimeZoneInfo.Bias) / 60 );
 CString csLocalTimeInGmt;
 csLocalTimeInGmt.Format( _T("%ld:%ld:%ld + %2.1f Hrs"),
                          GmtTime.wHour,
                          GmtTime.wMinute,
                          GmtTime.wSecond,
                          TimeZoneDifference );

Question: How do you get TIME_TIMEZONE_INFORMATION for a specific time zone?

, , API win32. MSDN TIME_ZONE_INFORMATION Win32?

C.

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