The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis
#include <iostream>
#include <sstream>
#include <bitset>
using namespace std;
int main()
{
ostringstream os;
// decimal and hexadecimal value
os << "dec: " << 15 << hex << " hex: " << 15 << endl;
cout << os.str() << endl;
// append floating value and bitset
bitset<15> b(5789);
os << "float: " << 4.67 << " bitset: " << b << endl;
// overwrite with octal value
os.seekp(0);
os << "oct: " << oct << 15;
cout << os.str() << endl;
}