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# init(unsafeRetaining:)

Creates a read-only buffer by retaining the existing PCM buffer without copying.

```
init(unsafeRetaining buffer: sending AVAudioPCMBuffer)
```

## Parameters

`buffer`

The PCM buffer to retain (not copied).

## Discussion> Warning: The caller must ensure the original buffer is not modified while this
> read-only buffer is in use. Violating this contract results in undefined behavior.

---

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