ENVIRONMENT DIVISION.
       INPUT-OUTPUT SECTION.
       FILE-CONTROL.
          SELECT A ASSIGN TO 'C:\OC\input.txt'
          ORGANIZATION IS LINE SEQUENTIAL.  

 1        IDENTIFICATION  DIVISION.
 2        PROGRAM-ID.     HELLO.
 3 
 4        ENVIRONMENT DIVISION.
 5        INPUT-OUTPUT SECTION.
 6        FILE-CONTROL.
 7           SELECT A ASSIGN TO 'C:\OC\input.txt'
 8           ORGANIZATION IS LINE SEQUENTIAL.
 9 
10           DATA DIVISION.
11           FILE SECTION.
12       *FD語句主要用來描述與文件記錄相關的物理信息，如記錄實際格式，長度等。
13           FD A.
14           01 STUDENT-FILE.
15               05 STUDENT-ID PIC 9(5).
16               05 WS-NAME PIC A(25).
17 
18 
19           WORKING-STORAGE SECTION.
20           01 WS-STUDENT.
21               05 WS-STUDENT-ID PIC 9(5).
22               05 WS-NAME PIC A(25).
23           01 WS-EOF PIC A(1).
24 
25       *程序運行主體部分
26        PROCEDURE DIVISION.
27       *打開文件A作為輸入文件，類似于c中的讀取文件
28           OPEN INPUT A.
29       *循環讀取文件A，并將數據放入WS-STUDENT，并打印WS-STUDENT
30              PERFORM UNTIL WS-EOF='Y'
31                 READ A INTO WS-STUDENT
32                    AT END MOVE 'Y' TO WS-EOF
33                    NOT AT END DISPLAY WS-STUDENT
34       *讀取完畢后，關閉所有讀取，結束循環，關閉文件A
35                 END-READ
36               END-PERFORM.
37           CLOSE A.
38        STOP RUN.

       IDENTIFICATION  DIVISION.
       PROGRAM-ID.     HELLO.

       ENVIRONMENT DIVISION.
          INPUT-OUTPUT SECTION.
          FILE-CONTROL.
      *寫入文件，一般為絕對文件 
          SELECT STUDENT ASSIGN TO 'C:\OC\input.txt'
             ORGANIZATION IS SEQUENTIAL
             ACCESS IS SEQUENTIAL.

       DATA DIVISION.
          FILE SECTION.
      *FD語句主要用來描述與文件記錄相關的物理信息，如記錄實際格式，長度等。
          FD STUDENT.
          01 STUDENT-FILE.
              05 STUDENT-ID PIC 9(5).
              05 NAME PIC A(25).
              05 CLAS PIC X(3).


          WORKING-STORAGE SECTION.
          01 WS-STUDENT.
              05 WS-STUDENT-ID PIC 9(5).
              05 WS-NAME PIC A(25).
              05 WS-CLASS PIC X(3).

      *程序運行主體部分
       PROCEDURE DIVISION.
      *打開要寫入文件
          OPEN EXTEND STUDENT.
             MOVE 1000 TO STUDENT-ID.
             MOVE 'TIM' TO NAME.
             MOVE '10' TO CLAS.
      *將暫存文件STUDENT-FILE寫入文件
             WRITE STUDENT-FILE
             END-WRITE.
          CLOSE STUDENT.
       STOP RUN.