/sys$common/syshlp/helplib.hlb FORTRAN, Statements, INQUIRE, SEQUENTIAL  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  SEQUENTIAL = seq

  seq  Is a character scalar memory reference that is
       assigned one of the following values:

  'YES'       If sequential access is allowed for the
              specified file
  'NO'        If sequential access is not allowed
  'UNKNOWN'   If the access mode cannot be determined