Passing arguments – PB Docs 2019

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:

The syntax for an argument that is passed by value is: