The SET statement sets values of indexes associated with table
  elements.  It can also change the value of a conditional variable,
  change the status of an external switch, and store the address of a
  COBOL identifier reference at run time.

  Format 6 -

   SET status-code-id TO { SUCCESS }
                         { FAILURE }

1  –  status-code-id

  is a word or longword integer data item represented by PIC S9(1) to
  S9(9) COMP.