Change timezone with TZ environment variable in Windows

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:
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