SystemTimeToTzSpecificLocalTime function (timezoneapi.h)

Converts a time in Coordinated Universal Time (UTC) to a specified time zone's corresponding local time.

BOOL SystemTimeToTzSpecificLocalTime(
  [in, optional] const TIME_ZONE_INFORMATION *lpTimeZoneInformation,
  [in]           const SYSTEMTIME            *lpUniversalTime,
  [out]          LPSYSTEMTIME                lpLocalTime
);

[in, optional] lpTimeZoneInformation

A pointer to a TIME_ZONE_INFORMATION structure that specifies the time zone of interest.

If lpTimeZone is NULL, the function uses the currently active time zone.

[in] lpUniversalTime

A pointer to a SYSTEMTIME structure that specifies the UTC time to be converted. The function converts this universal time to the specified time zone's corresponding local time.

[out] lpLocalTime

A pointer to a SYSTEMTIME structure that receives the local time.

If the function succeeds, the return value is nonzero, and the function sets the members of the SYSTEMTIME structure pointed to by lpLocalTime to the appropriate local time values.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

The SystemTimeToTzSpecificLocalTime function takes into account whether daylight saving time (DST) is in effect for the local time to which the system time is to be converted.

The SystemTimeToTzSpecificLocalTime function may calculate the local time incorrectly under the following conditions:

• The time zone uses a different UTC offset for the old and new years.
• The UTC time to be converted and the calculated local time are in different years.

For an example, see Retrieving the Last-Write Time.

GetSystemTime

GetTimeZoneInformation

SYSTEMTIME

System Time

TIME_ZONE_INFORMATION

Time Functions

TzSpecificLocalTimeToSystemTime