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# isRenderingOffline

Communicates to an audio unit that it is rendering offline.

```
var isRenderingOffline: Bool { get set }
```

## Discussion

A host should use this property when using an audio unit in a context where there are no realtime deadlines. An audio unit may respond by using a more expensive signal processing algorithm, or allowing itself to block at render time if data being generated on secondary work threads is not ready in time.

This version 3 property is bridged to the version 2 `kAudioUnitProperty_OfflineRender` API.

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