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# kAudioFileStreamProperty_AudioDataByteCount

A `UInt64` value indicating the number of bytes of audio data in the streamed file. This property is valid only if the number of bytes for the entire stream is known from the data parsed in the header. For some kinds of streams this property may have no value.

```
var kAudioFileStreamProperty_AudioDataByteCount: AudioFileStreamPropertyID { get }
```

---

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