          ONKEY          subprogram                            PAGE  O3
          -------------------------------------------------------------

          Format         CALL ONKEY(string,key-unit,return-variable,
                         status-variable) GOTO line-number[,...]

                         CALL ONKEY(string-variable,key-unit,
                         return-variable,status-variable) 
                         GOTO line-number[,...]  

          Description

          ONKEY compares a string or string-variable characters one at  
          a time to the key return-variable until a match is found. 
          The string length may be longer then the number of GOTO
          line-number list. But a error results if that key is pressed
          as no line-number corresponds with the position of the key.
          If the string length is less than the number of GOTO line-
          numbers then the extra GOTO line-numbers are not used.
          The position of the characters in the string correspond to
          the GOTO line-number in the list. i.e. string "12345" 
          GOTO 1,2,3,4,5 in the example:

          CALL ONKEY("12345",0,K,S) GOTO 10,20,30,40,50
          The key pressed like say 3 means line 30 will be used.

          Another example: 
          10 CALL ONKEY("Test",0,K,S) GOTO 22,29,34,41 :: GOTO 10
          If T is pressed then 22 is used.
          If e is pressed then 29 is used.
          If s is pressed then 34 is used.
          If t is pressed then 41 is used.

          If no key pressed GOTO 10 to repeat line.