C%%A-RCB-0077-SL-12    LST -- 1  PROMPT AND OPEN FILES
C     Events:   1  Initial entry -- loops to itself
C               2  Files open
C               3  Last command was on MCR line -- time to exit
C
100   ENCODE (HD1LNG,110,BHEAD1)
110   FORMAT (<HD1LNG> (X))
      IEVENT = 3
      IF(BMCR) GO TO 10
      IEVENT = 2
      CALL LSTOPN(LUT,LUDI,LUW)
      IF(BOLD) GO TO 10
           WRITE(LUT,120) PROMPT,BNAMIN
120        FORMAT('0',A3,': NONEXISTENT INPUT FILE ',32A1/)
           GO TO 100

C%%A-RCB-0077-SL-12    LST -- 2  EXAMINE EXTENSION TO IDENTIFY FILE TYPE
C     Events:   1  LST files
C               2  TXT files
C               3  Other files
C
200   IEVENT = 3
      IF(EXTN.EQ.DEFALT) IEVENT = 1
      IF(EXTN.EQ.TXT) IEVENT = 2
      IF (EXTN.EQ.FCC) IEVENT = 2
      GO TO 10

C%%A-RCB-0077-SL-12    LST -- 3  EXAMINE HEADER OF LST FILE TO DETERMINE TYPE
C     Events:   1  FOR, V6B
C               2  F4P
C               3  MAC
C               4  Other
C
300   IEVENT = 4
      ENCODE(16,305,BVERSN)
305   FORMAT(16X,T1,'V01B-02A')
      IF (.NOT.COMPAR(BVERSN,BUFFER(IFIRST+13-1),8,8)) GO TO 320
      IEVENT = 1
      GO TO 10
C
320   ENCODE(16,325,BVERSN)
325   FORMAT(16X,T1,'V02-51')
      IF (.NOT.COMPAR(BVERSN,BUFFER(IFIRST+18-1),6,6)) GO TO 340
      IEVENT = 2
      GO TO 10
C
340   ENCODE (16,345,BVERSN)
345   FORMAT (16X,T1,'MACRO D1013')
      IPTR = ILAST
      DO 350 I = IFIRST,ILAST
           IF (BUFFER(IPTR).NE.BTAB) IPTR = IPTR - 1
350   CONTINUE
      IF (IPTR.GT.ILAST-11) GO TO 10
      IF (.NOT.COMPAR(BVERSN,BUFFER(IPTR+1),11,11)) GO TO 10
      ILAST = IPTR - 1
      IEVENT = 3
      GO TO 10

C%%A-RCB-0077-SL-12    LST -- 4  EXAMINE HEADER OF LST FILE
C     Events:   1  RATFOR Version 2
C               2  Other
C               3  Other
C               4  Other
C
400   IEVENT = 4
C
      ENCODE(16,405,BVERSN)
405   FORMAT(16X,T1,'RATFOR VERSION 2')
      IF (.NOT.COMPAR(BVERSN,BUFFER(IFIRST+1),16,16)) GO TO 420
      IEVENT = 1
      GO TO 10
C
420   GO TO 9500
C
500   GO TO 9400
C
600   GO TO 9400
C
700   GO TO 9400
C
800   GO TO 9400

C%%A-RCB-0077-SL-12    LST -- 9  EXIT
C     Used if command was on MCR line only.  Otherwise LSTOPN exits internally.
C
900   CALL EXIT