The following code example is taken from the book
Object-Oriented Programming in C++
by Nicolai M. Josuttis, Wiley, 2002
© Copyright Nicolai M. Josuttis 2002
#include <iostream>
#include <strstream>
int main()
{
// create dynamic char* stream for writing
std::ostrstream buffer;
// write formatted string and append end-of-string character
buffer << "Pi: " << 3.1415 << std::ends;
/* output character string
* - str() freezes the char* stream
*/
std::cout << buffer.str() << std::endl;
// cancel the freezing
buffer.freeze(false);
// position so that std::ends is overwritten
buffer.seekp(-1,std::ios::end);
// write into char* stream further
buffer << " or also: " << std::scientific << 3.1415
<< std::ends;
/* output character string
* - str() freezes the char* stream
*/
std::cout << buffer.str() << std::endl;
// cancel the freezing, so that memory is freed by char* stream destructor
buffer.freeze(false);
}