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# DequeueWithCoalesce

Removes the next queue entry, but doesn’t automatically send notifications.

```
kern_return_t DequeueWithCoalesce(bool *sendDataServiced, IODataQueueClientDequeueEntryBlock callback);
```

## Parameters

`sendDataServiced`

A Boolean value that indicates that this method would have sent a notification. Initialize the value to `false`, and then make one or more calls to this method. If the value is `true` after all of those calls, call the [`SendDataServiced`](/documentation/DriverKit/IODataQueueDispatchSource/SendDataServiced) method yourself to deliver the notification.

`callback`

The callback that you use to process the dequeued data.

## Return Value

[`kIOReturnSuccess`](/documentation/DriverKit/kIOReturnSuccess) on success, [`kIOReturnUnderrun`](/documentation/DriverKit/kIOReturnUnderrun) if the queue is empty, or [`kIOReturnError`](/documentation/DriverKit/kIOReturnError) if the queue is corrupt. See [Error Codes](/documentation/DriverKit/error-codes).

---

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