VMS Help FORTRAN, Statements, INQUIRE, EXIST  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  EXIST = lv

  lv  Is a logical scalar memory reference that is
      assigned one of the following values:

  .TRUE.    If the specified file exists and can be opened
            or if the unit exists
  .FALSE.   If the specified file or unit does not exist or
            if the file exists but cannot be opened

  The unit exists if it is a number in the range allowed by the
  processor.