导出托管c#函数，将修改后的char*参数返回给非托管代码

I have a native C++ (I think) app which can be configured to load a certain dll and call a function. This function returns int, takes in four parameters, should change at least one of the two and return a value. According to the manual this function should be defined in C++ as:I have a native C++ (I think) app which can be