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# IOUSBBOSDescriptor

The structure for storing a binary object store (BOS) descriptor.

```
struct IOUSBBOSDescriptor;
```

## Overview

For more information about this descriptor type, see section 9.6.2 of the USB 3.2 specification at <http://www.usb.org>.

## Topics

### Accessing the Descriptor Properties

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

The size of the descriptor in bytes.

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

The type of the descriptor.

[`uint16_t wTotalLength;`](/documentation/USBDriverKit/IOUSBBOSDescriptor/wTotalLength)

The length, in bytes, of the descriptor and all of its subdescriptors.

[`uint8_t bNumDeviceCaps;`](/documentation/USBDriverKit/IOUSBBOSDescriptor/bNumDeviceCaps)

The number of separate device capability descriptors in the binary object store.


---

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