GetTimeZoneInformation

GetTimeZoneInformation retrieves the current time-zone parameters. These parameters control the translations between UTC and local time.

Syntax

DWORD
    GetTimeZoneInformation(
    LPTIME_ZONE_INFORMATION              lpTimeZoneInformation
);

Parameters

lpTimeZoneInformation

Pointer to a TIME_ZONE_INFORMATION structure to receive the current time-zone parameters.

Return Value

One of the following values if the function succeeds:

Value	Description
TIME_ZONE_ID_UNKNOWN	The system cannot determine the current time zone. If daylight savings time is not used in the current time zone, this value is returned because there are no transition dates.
TIME_ZONE_ID_STANDARD	The system is operating in the range covered by the StandardDate member of the TIME_ZONE_INFORMATION structure.
TIME_ZONE_ID_DAYLIGHT	The system is operating in the range covered by the DaylightDate member of the TIME_ZONE_INFORMATION structure.
TIME_ZONE_ID_INVALID	TIME_ZONE_ID_INVALID if the function fails

To get extended error information, call GetLastError.

Remarks

All translations between UTC and local time are based on the following formula.

UTC = local time + bias

The bias is the difference, in minutes, between UTC and local time.

If a call to SetTimeZoneInformation supplies a bias value but no transition date, GetTimeZoneInformation will return either TIME_ZONE_ID_STANDARD or TIME_ZONE_ID_DAYLIGHT.

Requirements

Minimum Supported Version	RTX64 2013
Header	windows.h
Library	Rtx_Rtss.lib