Here are the data structures with brief descriptions:

Clibusb_config_descriptor	A structure representing the standard USB configuration descriptor
Clibusb_control_setup	Setup packet for control transfers
Clibusb_device_descriptor	A structure representing the standard USB device descriptor
Clibusb_endpoint_descriptor	A structure representing the standard USB endpoint descriptor
Clibusb_interface	A collection of alternate settings for a particular USB interface
Clibusb_interface_descriptor	A structure representing the standard USB interface descriptor
Clibusb_iso_packet_descriptor	Isochronous packet descriptor
Clibusb_pollfd	File descriptor for polling
Clibusb_transfer	The generic USB transfer structure
Clibusb_version	Structure providing the version of the libusbx runtime