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# kAudioFilePropertyReserveDuration

The duration in seconds of the data expected to be written. Set this property before any data has been written to reserve space in the file header for a packet table and other information to appear before the audio data. Otherwise, the packet table might get written at the end of the file, preventing the file from being streamable.

```
var kAudioFilePropertyReserveDuration: AudioFilePropertyID { get }
```

---

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