If I use string class for all strings in my code, how do I ensure compatibility with functions (e.g. math - atof()) that require char* type? In case of atof(), I use this: "atof(&thestring)". It works, because atof() has parameter as const, it doesn't change it. But if there is any other function with non-const char* parameter, how do I properly pass a string (from string class) to it?