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# AsyncCompletion

Send asynchronous arguments to a completion supplied by ExternalMethod().

```
virtual void AsyncCompletion(OSAction *action, IOReturn status, const IOUserClientAsyncArgumentsArray asyncData, uint32_t asyncDataCount);
```

## Parameters

`action`

OSAction passed to IOExternalMethod().

`status`

An IOReturn status value to be sent.

`asyncData`

An array of scalar data to be sent.

`asyncDataCount`

Count of valid data in asyncData.

## Discussion

IOConnectAsyncMethod calls from the owner of the connection come will pass an OSAction instance. To deliver the asynchronous results the driver calls AsyncCompletion().

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