VMS Help FORTRAN, Error Messages, Compilation Errors, EXT_OPER  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  SEVERITY:  I

  MESSAGE TEXT:  Extension to FORTRAN-77:  nonstandard operator

  EXPLANATION:  The operators .XOR., %VAL, %REF, %DESCR, and %LOC are
  extensions to FORTRAN-77.  The standard form of .XOR. is .NEQV.
  The % operators are extensions provided to allow access to
  non-Fortran parts of the VMS environment.