Retrieves the daylight saving time offset in seconds.
The _get_dstbias function retrieves the number of seconds in daylight saving time as an integer. If daylight saving time is in effect, the default offset is 3600 seconds, which is the number of seconds in one hour (though a few regions do observe a two-hour offset).
If seconds is NULL, the invalid parameter handler is invoked as described in Parameter Validation. If execution is allowed to continue, this function sets errno to EINVAL and returns EINVAL.
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.