dio_select_device

	status.i4.v = dio_select_device(dio_find_devices_matches_t const &candidates,
					int &selected_di)

	A routine that asks user to select a device from a list of devices
	previously found by a call to dio_find_devices.  This capability is
	is not included within dio_find_devices, to allow non-PA environments
	to use UIs other than clib UI.  If the candidate list contains only a
	a single device that device's device index will be selected without
	any user interaction.

	candidates	input argument for candidate devices. Expectation is
			that this list will be obtained from call to
			dio_find_devices.
	selected_di	input argument.  Device index of selected device if
			returned status is OK.

	This function returns ACNET status values as follows:

	OK			success (user selected a device)
	DIO_NO_SUCH		user did not select a device.
	DIO_BADARG		candidates list is empty
	other value		something went wrong

	This function requires the following include files:

	AcnetStatus_h, diolib_h

	Related functions:

	dio_find_devices

	C++ usage:

	std::string const pattern("%out%");

	dio_find_devices_matches_t device_matches;

	int status = dio_find_devices(candidates,device_matches);
	if (status == OK)
	    {
	    int di;
	    status = dio_select_device(device_matches,di);
	    // Do something with selected device
	    }
	else if (status == DIO_NO_SUCH)
	    {
	    // Error handling code
	    }