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# kAudioUnitProperty_FastDispatch

A read-only `void *` value valid on the audio unit global scope.

```
var kAudioUnitProperty_FastDispatch: AudioUnitPropertyID { get }
```

## Discussion

This property supports expedited interaction with an audio unit. To use it, call the [`AudioUnitGetProperty(_:_:_:_:_:_:)`](/documentation/AudioToolbox/AudioUnitGetProperty(_:_:_:_:_:_:)) function with the `inID` parameter set to the selector constant that corresponds to the audio unit function you want to call quickly. On return, the `outData` parameter contains a function pointer for the selector.

For example, by calling [`AudioUnitGetProperty(_:_:_:_:_:_:)`](/documentation/AudioToolbox/AudioUnitGetProperty(_:_:_:_:_:_:)) with its `inID` parameter set to `kAudioUnitRenderSelect`, you obtain the function pointer for the [`AudioUnitRender(_:_:_:_:_:_:)`](/documentation/AudioToolbox/AudioUnitRender(_:_:_:_:_:_:)) function. You can then invoke audio unit rendering without incurring the overhead of the component dispatch mechanism.

---

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