TIME_ZONE_INFORMATION

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Windows Embedded CE 6.0 R3

4/8/2010

This structure specifies information specific to the time zone.

Syntax

typedef struct _TIME_ZONE_INFORMATION {
  LONG Bias;
  WCHAR StandardName[32];
  SYSTEMTIME StandardDate;
  LONG StandardBias;
  WCHAR DaylightName[32];
  SYSTEMTIME DaylightDate;
  LONG DaylightBias;
} TIME_ZONE_INFORMATION;

Members

• Bias
  Specifies the current bias, in minutes, for local time translation on this computer.

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

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

  UTC = local time + bias
  

  This member is required.

• StandardName
  Specifies a null-terminated string associated with standard time on this OS. For example, this member could contain EST to indicate Eastern Standard Time.

  This string is not used by the OS, so anything stored there by using the SetTimeZoneInformation function is returned unchanged by the GetTimeZoneInformation function.

  This string can be empty.

• StandardDate
  Specifies a SYSTEMTIME structure that contains a date and local time when the transition from daylight time to standard time occurs on this OS.

  If this date is not specified, the wMonth member in the SYSTEMTIME structure must be zero.

  If this date is specified, the DaylightDate value in the TIME_ZONE_INFORMATION structure must also be specified.

  This member supports one date format:

  • Day-in-month format is specified by setting the wYear member to zero, setting the wDayOfWeek member to an appropriate weekday, and using a wDay value in the range 1 through 5 to select the correct day in the month. Using this notation, the first Sunday in April can be specified, as can the last Thursday in October (5 is equal to the last).

• StandardBias
  Specifies a bias value to be used during local time translations that occur during standard time.

  This value is added to the value of the Bias member to form the bias used during standard time. In most time zones, the value of this member is zero.

• DaylightName
  Specifies a null-terminated string associated with daylight time on this OS. For example, this member could contain PDT to indicate Pacific Daylight Time.

  This string is not used by the OS, so anything stored there by using the SetTimeZoneInformation function is returned unchanged by the GetTimeZoneInformation function.

  This string can be empty.

• DaylightDate
  Specifies a SYSTEMTIME structure that contains a date and local time when the transition from standard time to daylight time occurs on this OS.

  If this date is not specified, the wMonth member in the SYSTEMTIME structure must be zero. If this date is specified, the StandardDate value in the TIME_ZONE_INFORMATION structure must also be specified.

  This member supports the day-in-month time format described for the StandardDate member.

• DaylightBias
  Specifies a bias value to be used during local time translations that occur during daylight time.

  This member is ignored if a value for the DaylightDate member is not supplied.

  This value is added to the value of the Bias member to form the bias used during daylight time.

  In most time zones, the value of this member is –60.

Requirements

See Also

Reference

Time Structures
GetTimeZoneInformation
SetTimeZoneInformation
SYSTEMTIME

Other Resources