Standard C++ Library
Copyright 1998, Rogue Wave Software, Inc.

NAME

 
cerr
 
 - Controls output to an unbuffered stream buffer associated with the object stderr declared in <cstdio>. 
 
 
 

SYNOPSIS

 
 
#include <iostream>
extern ostream cerr;
ostream cerr;
 
 
 

DESCRIPTION

 
 
The object cerr controls output to an unbuffered stream buffer associated with the object stderr declared in <cstdio>. By default, the standard C and C++ streams are synchronized, but you can improve performance by using the ios_base member function synch_with_stdio to desynchronize them. 
 
 
 

FORMATTING

 
 
The formatting is done through member functions or manipulators. See cout or basic_ostream for details. 
 
 
 

EXAMPLE

 
 
 
//
// cerr example
//
#include<iostream>
#include<fstream>
 
void main ( )
{

using namespace std;

// open the file "file_name.txt"
// for reading

ifstream in("file_name.txt");
 

// output the all file to stdout

if ( in )

cout << in.rdbuf();

else

// if the ifstream object is in a bad state
// output an error message to stderr

cerr << "Error while opening the file" << endl;

}
 
 
 

SEE ALSO

 
 
basic_ostream(3C++), basic_iostream(3C++), basic_filebuf(3C++), cout(3C++), cin(3C++), clog(3C++), wcin(3C++), wcout(3C++), wcerr(3C++), wclog(3C++), iomanip(3C++), ios_base(3C++), basic_ios(3C++)
 
Working Paper for Draft Proposed International Standard for Information Systems--Programming Language C++, Section 27.3.1
 
 
 

STANDARDS CONFORMANCE

 
 
ANSI X3J16/ISO WG21 Joint C++ Committee
 

Rogue Wave Software  —  Last change: 02 Apr 1998