If there is a specific key that has to be used as the starting point for the reverse process, then that key should be entered into the RIDFLD field.  The Start Browse Command Should Be Issued  Send out a READNEXT COMMAND, which really begins the reading process from the key that was supplied.  Now, issue the READPREV command, and put this read prior into a loop, continuing the loop until the necessary condition is satisfied.  Move LOW-VALUES into the Key field and continue with the same approach as described above if it is necessary to read the file in reverse order starting from the most recent entries and working backwards.