openusb_init, openusb_fini -- Initialize or destroy a libopenusb instanceopenusb_set_debug -- Set debug informationopenusb_set_event_callback, openusb_coldplug_callbacks_done -- Set event callbacks or Waiting for coldplug events completionopenusb_set_default_timeout -- Set default timeout for USB transferThese functions comprise the core of Openusb. They are used by all applications that utilize libopenusb.