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# IOUSBDFUDescriptor

A structure that defines the USB device firmware update descriptor.

```
struct IOUSBDFUDescriptor;
```

## Overview

See the USB Device Firmware Update Specification at <http://www.usb.org>.

## Topics

### Accessing the Descriptor Properties

[`uint8_t bLength;`](/documentation/USBDriverKit/IOUSBDFUDescriptor/bLength)

[`uint8_t bDescriptorType;`](/documentation/USBDriverKit/IOUSBDFUDescriptor/bDescriptorType)

[`uint8_t bmAttributes;`](/documentation/USBDriverKit/IOUSBDFUDescriptor/bmAttributes)

[`uint16_t wDetachTimeout;`](/documentation/USBDriverKit/IOUSBDFUDescriptor/wDetachTimeout)

[`uint16_t wTransferSize;`](/documentation/USBDriverKit/IOUSBDFUDescriptor/wTransferSize)


---

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