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# FreeBlock

A function to call once when the `CMBlockBuffer` is disposed.

```
var FreeBlock: ((UnsafeMutableRawPointer?, UnsafeMutableRawPointer, Int) -> Void)?
```

## Discussion

Pass `NULL` if you don’t want a function to be called after disposal. The function will not be called if no memory block is ever allocated or supplied.

---

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