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# setReadHandler(_:maxDatagrams:)

Set a read handler for datagrams.

```
func setReadHandler(_ handler: @escaping ([Data]?, (any Error)?) -> Void, maxDatagrams: Int)
```

## Parameters

`handler`

A handler called when datagrams have been read, or when an error has occurred.

`maxDatagrams`

The maximum number of datagrams to send to the handler.

## Discussion

Reads will be scheduled by the system, so this method only needs to be called once for a session.

---

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