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usbd_device_descriptor()

Get the device descriptor for a specific device

Synopsis:

#include <sys/usbdi.h>

usbd_device_descriptor_t 
  *usbd_device_descriptor(                                           
    struct usbd_device *device,                           
    struct usbd_desc_node **node );

Arguments:

device: A handle obtained by calling usbd_attach().
node: The address of a pointer to a usbd_device_descriptor_t structure where the function stores the device descriptor.

Library:

libusbdi

Description:

The usbd_device_descriptor() function lets you obtain the device descriptor for a specific device.

The node parameter tells you where a descriptor was found to root future requests from (e.g. configurations of the device).

The usbd_device_descriptor_t structure looks like this:

typedef struct usbd_device_descriptor {
    _uint8                  bLength;
    _uint8                  bDescriptorType;
    _uint16                 bcdUSB;
    _uint8                  bDeviceClass;
    _uint8                  bDeviceSubClass;
    _uint8                  bDeviceProtocol;
    _uint8                  bMaxPacketSize0;
    _uint16                 idVendor;
    _uint16                 idProduct;
    _uint16                 bcdDevice;
    _uint8                  iManufacturer;
    _uint8                  iProduct;
    _uint8                  iSerialNumber;
    _uint8                  bNumConfigurations;
} usbd_device_descriptor_t;

Returns:

A pointer to usbd_device_descriptor_t on success, or NULL on error.

Classification:

QNX Neutrino, QNX 4

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	No
Thread	Yes