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# kAudioFilePropertyDeferSizeUpdates

The default value (`0`) always updates header. If set to `1`, updating the files sizes in the header is not performed every time data is written. Instead, the updating is deferred until the file has been read, optimized, or closed. This process is more efficient, but not as safe. If an application crashes before the size has been updated, the file might not be readable.

```
var kAudioFilePropertyDeferSizeUpdates: AudioFilePropertyID { get }
```

---

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