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# SecMessageBlock

A block that delivers messages during asynchronous operations.

```
typealias SecMessageBlock = (CFTypeRef?, CFError?, Bool) -> Void
```

## Parameters

`message`

A CFType containing the message. This is where either intermediate or final results are returned.

`error`

If an error occurred, this will contain a CFErrorRef, otherwise this will be NULL. If not NULL the caller is responsible for releasing the CFErrorRef.

`isFinal`

If set the message returned is the final result otherwise it is an intermediate result.

## Discussion

---

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