VMS Help FORTRAN, Intrinsic Procedures, EXIT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  EXIT ([status])

  A subroutine that terminates the program, closes all files, and
  returns you to DCL command level.  The optional argument specifies
  the exit status of the program and defaults to SS$_NORMAL (a value
  of 1 -- normal completion of program).