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# requestReadData(atOffset:length:completion:)

Requests to asynchronously read data of a specified length from a specified offset, then executes the completion block.

```
func requestReadData(atOffset offset: off_t, length: off_t, completion: @escaping @Sendable (Data?, (any Error)?) -> Void)
```

## Discussion

The completion block executes on an any available queue; often this is not the main queue.

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