rw1.cbl

      *****************************************************************
       IDENTIFICATION DIVISION.
       PROGRAM-ID.  RW1.
       AUTHOR. Kamil Wdowicz.
      *
      *    Example on how to read from and write to files.
      *
      *****************************************************************
       ENVIRONMENT DIVISION.
       INPUT-OUTPUT SECTION.
       FILE-CONTROL.
           SELECT INFILE ASSIGN TO INPUTF
           ORGANIZATION IS SEQUENTIAL 
           FILE STATUS IS INFILE-FS.

           SELECT OUTFILE ASSIGN TO OUTPUTF
           ORGANIZATION IS SEQUENTIAL 
           FILE STATUS IS OUTFILE-FS.

       DATA DIVISION.
       FILE SECTION.
       FD INFILE RECORDING MODE F. 
       01 INFILE-STRUCT.
           05 NAME   PIC X(8).
           05 FILLER PIC X(1).
           05 NICK   PIC X(6).
           05 FILLER PIC X(65) VALUE SPACES.

       FD OUTFILE RECORDING MODE F.
       01 OUTFILE-STRUCT.
           05 NUM-O    PIC 9(3).
           05 FILLER   PIC X(1).
           05 NAME-O   PIC X(8).
           05 FILLER   PIC X(1).
           05 NICK-O   PIC X(6).
           05 FILLER   PIC X(61) VALUE SPACES.

       WORKING-STORAGE SECTION.
       01 WS-EOF     PIC A(1).
       01 INFILE-FS  PIC X(2).
       01 OUTFILE-FS PIC X(2).
       01 WS-NUM     PIC 9(3). 

       PROCEDURE DIVISION.
       OPEN-FILES.
           OPEN INPUT INFILE.
           OPEN OUTPUT OUTFILE.
           MOVE 0 TO WS-NUM.

       READ-WRITE-DISPLAY-UNTIL-END.
           PERFORM READ-FILE.
           PERFORM UNTIL WS-EOF = 'Y'
           PERFORM INCREASE-NUM
           PERFORM WRITE-FILE
           PERFORM DISPLAY-OUT
           PERFORM READ-FILE 
           END-PERFORM.

       CLOSE-STOP.
           CLOSE INFILE.
           CLOSE OUTFILE.
           STOP RUN.

       READ-FILE.
           READ INFILE
           AT END MOVE 'Y' TO WS-EOF
           END-READ.

       INCREASE-NUM.
           ADD 1 TO WS-NUM.

       WRITE-FILE.
           MOVE NAME TO NAME-O
           MOVE NICK TO NICK-O 
           WRITE OUTFILE-STRUCT.

       DISPLAY-OUT.
           DISPLAY OUTFILE-STRUCT.