<!--
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    "DriverKit: 21.0 -"
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  "framework" : "AudioDriverKit",
  "identifier" : "/documentation/AudioDriverKit/IOUserAudioDevice/AddStream",
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  "title" : "AddStream"
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# AddStream

Adds an audio stream to the device.

```
kern_return_t AddStream(IOUserAudioStream *in_stream);
```

## Parameters

`in_stream`

The stream to add to the device.

## Return Value

<doc://com.apple.documentation/documentation/DriverKit/kIOReturnSuccess> on success, or another value if an error occurs. For a list of error codes, see <doc://com.apple.documentation/documentation/DriverKit/error-codes>.

## Discussion

If adding the stream succeeds, the stream’s reference count increments by one.

---

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