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# AudioDevicePropertyListenerProc

```
typealias AudioDevicePropertyListenerProc = (AudioDeviceID, UInt32, DarwinBoolean, AudioDevicePropertyID, UnsafeMutableRawPointer?) -> OSStatus
```

## Parameters

`inDevice`

The AudioDevice whose property has changed.

`inChannel`

The channel of the property that changed where 0 is the main channel.

`isInput`

Which section of the AudioDevice changed.

`inPropertyID`

The AudioDevicePropertyID of the property that changed.

`inClientData`

A pointer to client data established when the listener proc was registered
with the object.

## Return Value

The return value is currently unused and should always be 0.

## Discussion

\abstract Clients register an AudioDevicePropertyListenerProc with the AudioDevice object
in order to receive notifications when the properties of the object change.
\discussion Note that the same functionality is provided by AudioObjectPropertyListenerProc.

---

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