Listing 3 The class ostrstream

class ostrstream: public ostream {
public:
       ostrstream();;
       ostrstream(char* s, int n, openmode mode = out);
       virtual ~ostrstream();
       strstreambuf* rdbuf() const;
       void freeze(int freezel = 1);
       char *str();
       int pcount() const;
private;
//      strstreambuf sb;   exposition only
};