The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference
by Nicolai M. Josuttis, Addison-Wesley, 1999
© Copyright Nicolai M. Josuttis 1999
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
// open file ``example.dat'' for reading and writing
filebuf buffer;
ostream output(&buffer);
istream input(&buffer);
buffer.open ("example.dat", ios::in | ios::out | ios::trunc);
for (int i=1; i<=4; i++) {
// write one line
output << i << ". line" << endl;
// print all file contents
input.seekg(0); // seek to the beginning
char c;
while (input.get(c)) {
cout.put(c);
}
cout << endl;
input.clear(); // clear eofbit and failbit
}
}