Subprogram arguments are either dummy arguments or actual arguments, and are specified as follows:
When control is transferred to a subprogram, each dummy argument takes the value of the corresponding actual argument. When control is returned to the calling program unit, the last value assigned to a dummy argument is assigned to the corresponding actual argument.
Section 6.1.1 describes the general techniques used to pass arguments between Fortran programs. Section 6.1.2 describes how to use Fortran built-in functions to pass arguments from within Fortran subprograms to subprograms written in other languages.