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# IOUSBGetEndpointMaxStreams(_:_:_:)

Obtains the number of supported streams.

```
func IOUSBGetEndpointMaxStreams(_ usbDeviceSpeed: UInt32, _ descriptor: UnsafePointer<IOUSBEndpointDescriptor>!, _ companionDescriptor: UnsafePointer<IOUSBSuperSpeedEndpointCompanionDescriptor>!) -> UInt32
```

## Parameters

`usbDeviceSpeed`

The operational speed of the device.

`descriptor`

The endpoint descriptor of the device.

`companionDescriptor`

The companion descriptor to parse.

## Return Value

The number of streams.

## Discussion

This method parses endpoint descriptors and returns the number of supported streams.

---

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