REM ************************************************************
REM *********    M 2 C B R I O . B A S  Ver  1.0   *************
REM *********        M2CBASIC TM    Ver 1.4        *************
REM *********                                      *************
REM *********        ALL RIGHTS RESERVED           *************
REM *********             07-21-84                 *************
REM ************************************************************

      DEF RANDOM.OPEN (FNUM%,FNAME$,REC.LEN%)
        INTEGER FNUM%,REC.LEN%
        STRING  FNAME$

        IF SIZE(FNAME$) > 0 \     8 = 2 QUOTES <CRLF> AND 4 FLAG BYTES
          THEN OPEN   FNAME$ RECL REC.LEN%+8 AS FNUM% \
          ELSE CREATE FNAME$ RECL REC.LEN%+8 AS FNUM%
        M2CB.RAND.BUF$(FNUM%) = SPACE$(REC.LEN%)
        M2CB.LOC%(FNUM%) = 0
        RETURN
      FEND

      DEF FIELD (FNUM%,OLD.ADDR%,ADDR%,WIDTH%)
        INTEGER FNUM%,OLD.ADDR%,ADDR%,WIDTH%,FOUND%,I%

        FOUND% = 0
        IF M2CB.NUM.FLDVARS% > 0 THEN \
          FOR I% = 1 TO M2CB.NUM.FLDVARS%: \
            IF M2CB.ADDR%(I%) = OLD.ADDR% \
              THEN FOUND% = -1 : GOTO END.SEARCH: \
          NEXT I% \
        ELSE FOUND% = 0

    END.SEARCH: IF FOUND% \
                  THEN GOSUB REPLACE.FLD \
                  ELSE GOSUB ADD.FLD
        M2CB.CUR.POS% = M2CB.CUR.POS% + WIDTH%
        RETURN  :     REM                      ***  EXIT  ***

      REPLACE.FLD: REM REPLACE FIELD VAR CONTENTS
        M2CB.FNUM%(I%)   = FNUM%
        M2CB.ADDR%(I%)   = ADDR%
        M2CB.START%(I%)  = M2CB.CUR.POS%
        RETURN

      ADD.FLD: REM ADD FIELD VAR
        M2CB.NUM.FLDVARS%               = M2CB.NUM.FLDVARS% + 1
        IF M2CB.NUM.FLDVARS% > M2CB.MAX.FLDVARS% \
          THEN PRINT "*** MAX. # OF FIELD VARS EXCEEDED ***":\
               PRINT "***  INCREASE M2CB.MAX.FLDVARS%   ***":\
               STOP
        M2CB.FNUM%(M2CB.NUM.FLDVARS%)   = FNUM%
        M2CB.ADDR%(M2CB.NUM.FLDVARS%)   = ADDR%
        M2CB.START%(M2CB.NUM.FLDVARS%)  = M2CB.CUR.POS%
        RETURN
      FEND


      DEF RANDOM.PUT (FNUM%,REC.NUM%)
        INTEGER FNUM%,REC.NUM%
        STRING  BUF$

        BUF$ = APNDCH(M2CB.RAND.BUF$(FNUM%)) :REM APPEND FLAGS

        IF REC.NUM% < 0 \
          THEN PRINT # FNUM%; BUF$ : M2CB.LOC%(FNUM%) = M2CB.LOC%(FNUM%)+1\
          ELSE PRINT # FNUM%, REC.NUM%; BUF$ : M2CB.LOC%(FNUM%) = REC.NUM%
        RETURN
      FEND


      DEF RANDOM.GET (FNUM%,REC.NUM%)
        INTEGER FNUM%,REC.NUM%,I%
        STRING  BUF$

        IF REC.NUM% < 0 \
          THEN READ # FNUM%; BUF$ :\
               M2CB.LOC%(FNUM%) = M2CB.LOC%(FNUM%)+1\
          ELSE READ # FNUM%, REC.NUM%; BUF$ :\
               M2CB.LOC%(FNUM%) = REC.NUM%

        M2CB.RAND.BUF$(FNUM%) = REMVCH(BUF$) :REM REMOVE FLAGS

        IF M2CB.NUM.FLDVARS% = 0 \
          THEN RETURN :REM       *** EXIT ***

        FOR I% = 1 TO M2CB.NUM.FLDVARS%
          IF M2CB.FNUM%(I%) = FNUM% \
            THEN \ SET FIELDED VAR
              CALL SETFDV (M2CB.ADDR%(I%), \
                           SADD(M2CB.RAND.BUF$(FNUM%)), \
                           M2CB.START%(I%))
        NEXT I%
        RETURN
      FEND

      DEF LRSET$ (MODE$,F.V.ADDR%,EXP$)
        INTEGER F.V.ADDR%,I%
        STRING  MODE$,EXP$,T$

        F.V.LEN% = PEEK(F.V.ADDR%+1) + 256*PEEK(F.V.ADDR%)
        EXP.LEN% = LEN(EXP$)

        IF EXP.LEN% >= F.V.LEN% \
          THEN T$ = MID$(EXP$,1,F.V.LEN%) \
          ELSE IF MODE$ = "L" \
                 THEN T$ = EXP$ + SPACE$(F.V.LEN%-EXP.LEN%) \
                 ELSE T$ = SPACE$(F.V.LEN%-EXP.LEN%) + EXP$

        CALL LRSETV (F.V.ADDR%, T$) :REM SET FIELD VAR TO T$

        IF M2CB.NUM.FLDVARS% = 0 \
          THEN RETURN :REM     *** EXIT ***

        FOR I% = 1 TO M2CB.NUM.FLDVARS%
          IF M2CB.ADDR%(I%) = F.V.ADDR% \
            THEN \ SET RANDOM BUFFER
              CALL SETRBF (SADD(M2CB.RAND.BUF$(M2CB.FNUM%(I%))), \
                           M2CB.START%(I%), \
                           T$)
        NEXT I%
        RETURN
      FEND