GetTimeZoneInformation

GetTimeZoneInformation is a function in the Windows API that retrieves information about the current time zone. This information includes the time zone name, the bias (difference between local time and Coordinated Universal Time, or UTC), the standard name, the daylight saving name, and the date and time when daylight saving time starts and ends.

The function returns a TIME_ZONE_INFORMATION structure that contains these details. The bias is expressed in minutes and is negative for time zones west of Greenwich and positive for those east of Greenwich. The standard name and daylight saving name are strings that represent the common abbreviations for these time periods. The start and end dates for daylight saving time are also provided, allowing applications to determine when these changes occur.

Applications can use GetTimeZoneInformation to perform various time-related operations, such as converting local time to UTC or vice versa, displaying accurate time zone information to users, and handling daylight saving time adjustments automatically. This function is crucial for any software that needs to work with time accurately across different geographical locations or during periods of daylight saving. The returned information can be used to adjust local time readings to reflect the correct offset from UTC and to account for the seasonal changes in time.