Retrieve a descriptor from the default control pipe.
This is a convenience function which formulates the appropriate control
message to retrieve the descriptor.
\param dev a device handle
\param desc_type the descriptor type, see \ref libusb_descriptor_type
\param desc_index the index of the descriptor to retrieve
\param data output buffer for descriptor
\param length size of data buffer
\returns number of bytes returned in data, or LIBUSB_ERROR code on failure
Retrieve a descriptor from the default control pipe. This is a convenience function which formulates the appropriate control message to retrieve the descriptor.
\param dev a device handle \param desc_type the descriptor type, see \ref libusb_descriptor_type \param desc_index the index of the descriptor to retrieve \param data output buffer for descriptor \param length size of data buffer \returns number of bytes returned in data, or LIBUSB_ERROR code on failure