If your program uses one of the following MFC or CRT function, then you can change timezone using TZ environment variable:
- CTime::GetLocalTm
- CTime::Format
- COleDateTime::operator=
- ctime
- _wctime
- _tctime
- _ctime64
- _wctime64
- _tctime64
- mktime
- _mktime64
- _utime
- _wutime
- _tutime
- _utime64
- _wutime64
- _tutime64
For example, to set the TZ environment variable to correspond to the current time zone in Germany, enter the following on the command line:
set TZ=GST-1GDT
This will add environment variable TZ with value ‘GST-1GDT’.
More about TZ environment variable:
Specifying the Time Zone with TZ
MSDN _tzset from Time Management