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# IOUSBHostIsochronousCompletionHandler

A completion handler for asynchronous isochronous transfers.

```
typealias IOUSBHostIsochronousCompletionHandler = (IOReturn, UnsafeMutablePointer<IOUSBHostIsochronousFrame>) -> Void
```

## Parameters

`status`

The result code for isochronous transfer.

`frameList`

The frame list of [`IOUSBHostIsochronousFrame`](/documentation/IOUSBHost/IOUSBHostIsochronousFrame) that [`enqueueIORequest(with:frameList:frameListCount:firstFrameNumber:completionHandler:)`](/documentation/IOUSBHost/IOUSBHostPipe/enqueueIORequest(with:frameList:frameListCount:firstFrameNumber:completionHandler:)) passes.

---

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