/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <iostream>
#include <streambuf>
#include <locale>
#include <cstdio>
class outbuf : public std::streambuf
{
protected:
/* central output function
* - print characters in uppercase mode
*/
virtual int_type overflow (int_type c) {
if (c != EOF) {
// convert lowercase to uppercase
c = std::toupper(c,getloc());
// and write the character to the standard output
if (putchar(c) == EOF) {
return EOF;
}
}
return c;
}
};
int main()
{
outbuf ob; // create special output buffer
std::ostream out(&ob); // initialize output stream with that output buffer
out << "31 hexadecimal: " << std::hex << 31 << std::endl;
}
|