PROGRAM FOR INDEXED SEQUENTIAL FILE CREATION (RANDOM MODE):
We have to write a program to create an Indexed Sequential File in random mode for Student particulars. Suppose just 2 fields: rno(Roll Number), name(Name  of Student) 
identification division.
  program- id.
  environment division.
  input-output section.
  file-control.
    select stu- file assign to disk
    organization is indexed
    access mode is random
    record key is rno
    file status is fs.
  data division.
  file section.
  fd stu- file
    label records are standard
    value of file- id is "stu.dat".
  01 stu-rec.
    02 rno pic 9(3).
    02 name pic x(20).
  working-storage section.
  01 fs pic x(2) value spaces.
  01 ans pic x value space.    
procedure division.  
p-1.
  open i-o stu-file.
  if fs = "30"
    open output stu-file
    close stu-file
    open i-o stu-file.
  perform g-w-para until ans = "n".
  close stu-file.
  stop run.
g-w-para.
display(1 1) erase.
display(3 5) "Rno : ".
accept rno.
display(5 5) "Name : ".
accept name.
write stu-rec invalid key display(15 5) "Error!".
display(20 5) "Continue [y/n] : ".