In PowerBuilder, you can define external functions that expect arguments to be passed by reference or by value. When you pass an argument by reference, the external function receives a pointer to the argument and can change the contents of the argument and return the changed contents to PowerBuilder. When you pass the argument by value, the external function receives a copy of the argument and can change the contents of the copy of the argument. The changes affect only the local copy; the contents of the original argument are unchanged.
The syntax for an argument that is passed by reference is:
REF datatype arg
The syntax for an argument that is passed by value is:
datatype arg
