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# readValue(completionHandler:)

Reads the value for the characteristic.

```
func readValue(completionHandler completion: @escaping @Sendable ((any Error)?) -> Void)
```

## Parameters

`completion`

The block executed after the request is processed.

- error: `nil` on success; otherwise, error object indicating the reason for failure.

## Discussion

The value is available from the [`value`](/documentation/HomeKit/HMCharacteristic/value) property after completion of the request.

---

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