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# tIOUSBDescriptorSize

Constants for the number of bytes in descriptor structures.

```
enum tIOUSBDescriptorSize : unsigned int;
```

## Topics

### Getting the Descriptor Size

[`kIOUSBDescriptorHeaderSize`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorHeaderSize)

The size of a descriptor header.

[`kIOUSBDescriptorSizeDevice`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeDevice)

The size of a device descriptor.

[`kIOUSBDescriptorSizeConfiguration`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeConfiguration)

The size of a configuration descriptor.

[`kIOUSBDescriptorSizeInterface`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeInterface)

The size of an interface descriptor.

[`kIOUSBDescriptorSizeEndpoint`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeEndpoint)

The size of an endpoint descriptor.

[`kIOUSBDescriptorSizeStringMinimum`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeStringMinimum)

The minimum size of a string descriptor.

[`kIOUSBDescriptorSizeStringMaximum`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeStringMaximum)

The maximum size of a string descriptor.

[`kIOUSBDescriptorSizeDeviceQualifier`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeDeviceQualifier)

The size of a device qualifier descriptor.

[`kIOUSBDescriptorSizeInterfaceAssociation`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeInterfaceAssociation)

The size of an interface association descriptor.

[`kIOUSBDescriptorSizeBOS`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeBOS)

The size of a binary object store descriptor.

[`kIOUSBDescriptorSizeDeviceCapability`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeDeviceCapability)

The size of a device capability descriptor.

[`kIOUSBDescriptorSizeUSB20ExtensionCapability`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeUSB20ExtensionCapability)

The size of a USB 2.0 extension capability descriptor.

[`kIOUSBDescriptorSizeSuperSpeedUSBDeviceCapability`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeSuperSpeedUSBDeviceCapability)

The size of a super-speed device capability descriptor.

[`kIOUSBDescriptorSizeContainerIDCapability`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeContainerIDCapability)

The size of a container ID capability descriptor.

[`kIOUSBDescriptorSizeHubMinimum`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeHubMinimum)

The minimum size of a hub descriptor.

[`kIOUSBDescriptorSizeHubMaximum`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeHubMaximum)

The maximum size of a hub descriptor.

[`kIOUSBDescriptorSizeSuperSpeedHub`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeSuperSpeedHub)

The size of a super-speed hub descriptor.

[`kIOUSBDescriptorSizeSuperSpeedUSBEndpointCompanion`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeSuperSpeedUSBEndpointCompanion)

The size of a super-speed endpoint companion descriptor.

[`kIOUSBDescriptorSizeSuperSpeedPlusIsochronousEndpointCompanion`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeSuperSpeedPlusIsochronousEndpointCompanion)

The size of a super-speed plus isochronous endpoint companion descriptor.

[`kIOUSBDescriptorSizeBillboardDeviceMinimum`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeBillboardDeviceMinimum)

The minimum size of a billboard descriptor.

[`kIOUSBDescriptorSizeBillboardDeviceMaximum`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizeBillboardDeviceMaximum)

The maximum size of a billboard descriptor.

[`kIOUSBDescriptorSizePlatformECIDCapability`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizePlatformECIDCapability)

The size of a platform ECID capability descriptor.

[`kIOUSBDescriptorSizePlatformCapability`](/documentation/USBDriverKit/tIOUSBDescriptorSize/kIOUSBDescriptorSizePlatformCapability)

The size of a platform capability descriptor.


---

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