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# kAudioOutputUnitProperty_SetInputCallback

A read/write `AURenderCallbackStruct` data structure valid on the audio unit global scope. When an output unit has been enabled for input operation, this callback can be used to provide a single callback to the host application from the input I/O proc, in order to notify the host that input is available and may be obtained by calling the `AudioUnitRender` function.

```
var kAudioOutputUnitProperty_SetInputCallback: AudioUnitPropertyID { get }
```

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