C2009   Invalid use of @ (pass by reference) operator

    Problem:  The pass by reference (@) operator has been applied to a
    variable explicitly declared with the FIELD statement or an array
    element.  Both field variables and array elements are passed by value
    in all cases and cannot be passed by reference.

    Solution:  If @ operator was applied to a field variable, pass the
    field by value.  Fields have global scope, so there may no reason to
    be passing the field at all.

    If the @ operator was applied to an array element, either pass the
    array element by value or pass the entire array along with the index
    to the array element.