Comedi Documentation . ... comedi_find_range -- search for range . ... int comedi_find_range (comedi_t * device, unsigned int subdevice, unsigned int channel, unsigned int unit, double min, double max); . The function comedi_find_range() tries to locate the optimal (smallest) range for the channel chan belonging to a subdevice of the comedi device device, that includes both min and max in units. If a matching range is found, the index of the matching range is returned. ... comedi_get_range . ...