[Closed] Passing arguments by reference to my custom maxscript function

How can I pass arguments by reference to my custom maxscript command (written in C++), change them and read new value in max script?

Value* MaxCommand_cf(Value** arg_list, int count) 
    { 
    //modify arg_list[0] 
    } 

In max script: 

arg = “something” 
    MaxCommand &arg --contents of arg are changed by   MaxCommand
    print arg --print new value of arg