1.9.1.2 Out parameters
For
out
parameters,
-
If
nil
is passed, the value from the method is returned without any conversion.
-
For a parameter whose type is an array type or a pointer type with a
size_is
attribute, the value can be a Lisp array. The contents of the array will be modified by the method and the array will be returned as a value.
-
Otherwise, the value should be a foreign pointer of the type that the FLI would generate for the parameter's type. The foreign pointer will be returned as a value.
LispWorks COM/Automation User Guide and Reference Manual - 22 Dec 2009