Iostreams part1(Chapter 2 of Thinking in C++ Vol 2)

code 1 #include <iostream>
2 #include <fstream>
3 using namespace std;
4
5 int main()
6 {
7 ifstream in("IOfile.cpp");
8 ofstream out("IOfile.out");
9 out << in.rdbuf();
in.close();
out.close();

ifstream in2("IOfile.out", ios::in | ios::out);
ostream out2(in2.rdbuf());
cout << in2.rdbuf();
out2 << "Where does this end up?";
out2.seekp(0, ios::beg);
out2 << "And what about this?";
in2.seekg(0, ios::beg);
cout << in2.rdbuf();
}