/sys$common/syshlp/helplib.hlb FORTRAN, Built-in Functions, %VAL  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  %VAL (arg)
  Forces an actual argument in a CALL statement or function reference
  to be passed by value:  the actual value of the argument is passed
  to the subprogram.  The argument must be 32 bits in size or less.
  If the argument is less than 32 bits in size, it is sign-extended
  to that size.