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# CopyStringDescriptor

Returns a descriptor from the device in the specified language.

```
virtual const IOUSBStringDescriptor * CopyStringDescriptor(uint8_t index, uint16_t languageID);
```

## Parameters

`index`

The descriptor’s index value.

`languageID`

The descriptor’s language ID. You can get the current list of valid language IDs at <https://www.usb.org/>.

## Return Value

A pointer to the descriptor, or `NULL` if the descriptor isn’t found. It’s your responsibility to free the returned descriptor.

## Discussion

This method uses a `GET_DESCRIPTOR` control request (USB 2.0, section 9.4.3) to fetch the string descriptor from the device. The method puts the `index` value in the low byte of the `wValue` field, and puts the `languageID` value in the `wIndex` field of the request structure.

---

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