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# EnqueueWithCoalesce

Adds an entry to the queue, but doesn’t automatically send a data-available notification.

```
kern_return_t EnqueueWithCoalesce(uint32_t dataSize, bool *sendDataAvailable, IODataQueueClientEnqueueEntryBlock callback);
```

## Parameters

`dataSize`

The size of the data to enqueue.

`sendDataAvailable`

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 [`SendDataAvailable`](/documentation/DriverKit/IODataQueueDispatchSource/SendDataAvailable) method yourself to deliver the notification.

`callback`

The callback to execute when there is enough space to enqueue the data.

## Return Value

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

---

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