Conversion of void*&

[Manisha Mirajkar]

I need to convert a void *& varibale from a C function to a perl
variable?And later use this value to call another C function.

eg :
My C functiona are -  MyCFunc(void *& arg)
                              -  MyFuncCalled(void *p)

XS File : void MyXSFunc()
                    void *& arg
                CODE :
                    MyCFunc(arg);
                    MyFuncCalled(arg);

How do I  typemap a void*& ?