These same exits provide an interface for your exit routine to inform the caller of your exit of the results of your exit's processing. You turn on bits in the response byte to pass this information to the caller. This gives the caller a cumulative response from all exit routines invoked to help the caller determine how to proceed when control is returned to it. Your exit should not turn bits in the response byte off, as there are some occasions when some bits of the response byte are turned on initially before control is given to your exit.