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usbd_configuration_descriptor()

Get the configuration descriptor for a specific configuration setting

Synopsis:

#include <sys/usbdi.h>

usbd_configuration_descriptor_t 
    *usbd_configuration_descriptor(
        struct usbd_device *device,
        _uint8 cfg, 
        struct usbd_desc_node **node );

Arguments:

device: An opaque handle used to identify the USB device.
cfg: The device's configuration identifier (bConfigurationValue).
node: Indicates the descriptor's location for rooting future requests (e.g. interfaces of this configuration).

Library:

libusbdi

Description:

The usbd_configuration_descriptor() function lets you obtain the configuration descriptor for a specific configuration setting.

The usbd_configuration_descriptor_t structure looks like this:

typedef struct usbd_configuration_descriptor {
    _uint8                  bLength;
    _uint8                  bDescriptorType;
    _uint16                 wTotalLength;
    _uint8                  bNumInterfaces;
    _uint8                  bConfigurationValue;
    _uint8                  iConfiguration;
    _uint8                  bmAttributes;
    _uint8                  MaxPower;
} usbd_configuration_descriptor_t;

Returns:

A pointer to usbd_configuration_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