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# renderOffline(_:to:)

Makes a render call to the engine operating in the offline manual rendering mode.

```
func renderOffline(_ numberOfFrames: AVAudioFrameCount, to buffer: AVAudioPCMBuffer) throws -> AVAudioEngineManualRenderingStatus
```

## Parameters

`numberOfFrames`

The number of PCM sample frames to render.

`buffer`

The PCM buffer the engine must render the audio for.

## Return Value

One of the status codes from [`AVAudioEngineManualRenderingStatus`](/documentation/AVFAudio/AVAudioEngineManualRenderingStatus). Irrespective of the returned status code, on exit, the output buffer’s [`frameLength`](/documentation/AVFAudio/AVAudioPCMBuffer/frameLength) indicates the number of PCM samples the engine renders.

## Discussion

---

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