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# CMBufferCompareCallback

Callback that compares one `CMBuffer` with another.

```
typealias CMBufferCompareCallback = (CMBuffer, CMBuffer, UnsafeMutableRawPointer?) -> CFComparisonResult
```

## Discussion

You can use a `CFComparatorFunction` as a callback.

### Callback parameters

- buf1: The first buffer being compared.
- buf2: The second buffer being compared.
- refcon: The contextual data from the client (which may be `NULL`).

---

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