Class std::string provides two member functions that return the const char * representation of its object: string::c_str() and string::data(). c_str() returns a null-terminated const pointer to char that represents the string object.

 void f(){  string  s = "Hello";  if(strcmp( s.c_str(), "Hello") == 0)    cout <<"identical"<

The member function string::data() also returns a const char * representation of its object, but it might not be null terminated, so data() should not be used in a context that requires a null-terminated character array.