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# kExtAudioFileProperty_IOBufferSizeBytes

The size of the buffer that the extended audio file object’s associated audio converter uses to read or write the associated audio file. Value is a read/write `UInt32`.

```
var kExtAudioFileProperty_IOBufferSizeBytes: ExtAudioFilePropertyID { get }
```

## Discussion

This property has a value only when there is an underlying audio converter object present.

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