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# IOUSBGetUSB20ExtensionDeviceCapabilityDescriptor

Finds the first USB 2.0 extension capability descriptor in a BOS descriptor.

```
const IOUSBDeviceCapabilityUSB2Extension *IOUSBGetUSB20ExtensionDeviceCapabilityDescriptor(const IOUSBBOSDescriptor *bosDescriptor);
```

## Parameters

`bosDescriptor`

The BOS descriptor that contains the descriptors to iterate through.

## Return Value

The descriptor pointer, or `NULL` if no matching descriptor can be found.

## Discussion

This method uses `getNextCapabilityDescriptorWithType` to fetch the first `USB20ExtensionCapabilityDescriptor.`

---

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