#include <stdio.h>

void put(char c, FILE *stream);
void put(const char *s, FILE *stream);

class File
        {
        FILE *f;
public:
        File(FILE *ff) : f(ff) { }
        void put(const char *s);
        };

void File::put(const char *s)
        {
        put(s, f);          // error
        }

int main()
        {
        File f(stdout);
        f.put("hello, world\n");
        return 0;
        }

