Relative file creation

       IDENTIFICATION DIVISION.
       PROGRAM-ID.
       ENVIRONMENT DIVISION.
       INPUT-OUTPUT SECTION.
       FILE-CONTROL.
           SELECT SFILE ASSIGN TO DISK
           ORGANIZATION IS RELATIVE
           ACCESS MODE IS RANDOM
           RECORD KEY SNO.
       DATA DIVISION.
       FILE SECTION.
       FD SFILE
      LABEL RECORDS ARE STANDARD
    VALUE OF FILE-ID IS "STD.REL".
       01 SREC.
   02 SNM PIC X(10).
   02 M PIC 9(3).
       WORKING-STORAGE SECTION.
       77 SNO PIC 9(5).
       77 CH PIC X VALUE SPACE.
       PROCEDURE DIVISION.
       MAIN-PARA.
           OPEN OUTPUT SFILE.
           PERFORM READ-DATA UNTIL CH = "N" OR "n".
           CLOSE SFILE.
           STOP RUN.
       READ-DATA.
           DISPLAY "ENTER REGISTRATION NUMBER: ".
           ACCEPT SNO.
           DISPLAY "ENTER STUDENT NAME: ".
           ACCEPT SNM.
           DISPLAY "ENTER MARKS SCORED: ".
           ACCEPT M.
           WRITE SREC INVALID KEY DISPLAY "INVALID DATA.".
           DISPLAY "CONTINUE (Y/N).".
           ACCEPT CH.