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# CFTimeZoneGetDaylightSavingTimeOffset(_:_:)

Returns the daylight saving time offset for a time zone at a given time.

```
func CFTimeZoneGetDaylightSavingTimeOffset(_ tz: CFTimeZone!, _ at: CFAbsoluteTime) -> CFTimeInterval
```

## Parameters

`tz`

The time zone to analyze.

`at`

The time in `tz` to test for daylight saving time offset.

## Return Value

The daylight saving time offset for `tz` at `at`.

## Discussion

---

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