---
title: kAudioUnitProperty_FastDispatch
framework: audiotoolbox
role: symbol
role_heading: Global Variable
path: audiotoolbox/kaudiounitproperty_fastdispatch
---

# kAudioUnitProperty_FastDispatch

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

## Declaration

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

## Discussion

Discussion This property supports expedited interaction with an audio unit. To use it, call the 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(_:_:_:_:_:_:) with its inID parameter set to kAudioUnitRenderSelect, you obtain the function pointer for the AudioUnitRender(_:_:_:_:_:_:) function. You can then invoke audio unit rendering without incurring the overhead of the component dispatch mechanism.

## See Also

### Properties

- [kAudioUnitProperty_ElementCount](audiotoolbox/kaudiounitproperty_elementcount.md)
- [kAudioUnitProperty_SupportedNumChannels](audiotoolbox/kaudiounitproperty_supportednumchannels.md)
- [kAudioUnitProperty_AudioChannelLayout](audiotoolbox/kaudiounitproperty_audiochannellayout.md)
- [kAudioUnitProperty_AudioUnitMIDIProtocol](audiotoolbox/kaudiounitproperty_audiounitmidiprotocol.md)
- [kAudioUnitProperty_AUHostIdentifier](audiotoolbox/kaudiounitproperty_auhostidentifier.md)
- [kAudioUnitProperty_BypassEffect](audiotoolbox/kaudiounitproperty_bypasseffect.md)
- [kAudioUnitProperty_ClassInfo](audiotoolbox/kaudiounitproperty_classinfo.md)
- [kAudioUnitProperty_ClassInfoFromDocument](audiotoolbox/kaudiounitproperty_classinfofromdocument.md)
- [kAudioUnitProperty_CocoaUI](audiotoolbox/kaudiounitproperty_cocoaui.md)
- [kAudioUnitProperty_ContextName](audiotoolbox/kaudiounitproperty_contextname.md)
- [kAudioUnitProperty_CPULoad](audiotoolbox/kaudiounitproperty_cpuload.md)
- [kAudioUnitProperty_DependentParameters](audiotoolbox/kaudiounitproperty_dependentparameters.md)
- [kAudioUnitProperty_ElementName](audiotoolbox/kaudiounitproperty_elementname.md)
- [kAudioUnitProperty_FactoryPresets](audiotoolbox/kaudiounitproperty_factorypresets.md)
- [kAudioUnitProperty_FrequencyResponse](audiotoolbox/kaudiounitproperty_frequencyresponse.md)