INTEGER FUNCTION IDX (SRC, STR)
C
C Find position of one string in another
C
C SRC = source string
C STR = target string
C
C Value of function is zero if not found,
C or position of first character of STR in SRC if found
C
	BYTE SRC(1), STR(1)
C
C Look for STR in SRC until end of SRC
C
	J = 0
10	J = J + 1
	I = 0
	IF (SRC(J) .EQ. 0) GOTO 30
C
C If end of STR then success
C If not match look at next position in SRC
C
20	IF (STR(I+1) .EQ. 0) GOTO 40
	IF (SRC(J+I) .NE. STR(I+1)) GOTO 10
	I = I + 1
	GOTO 20
C
C Return failure
C
30	IDX = 0
	RETURN
C
C Return success, position of string
C
40	IDX = J
	RETURN
C
	END