共用方式為


cerr

Specifies the cerr global stream.

extern ostream cerr;

Return Value

An ostream object.

Remarks

The object controls unbuffered insertions to the standard error output as a byte stream. Once the object is constructed, the expression cerr.flags & unitbuf is nonzero.

Example

// iostream_cerr.cpp
// compile with: /EHsc
// By default, cerr and clog are the same as cout
#include <iostream>
#include <fstream>

using namespace std;

void TestWide( ) 
{
   int i = 0;
   wcout << L"Enter a number: ";
   wcin >> i;
   wcerr << L"test for wcerr" << endl;
   wclog << L"test for wclog" << endl;   
}

int main( ) 
{
   int i = 0;
   cout << "Enter a number: ";
   cin >> i;
   cerr << "test for cerr" << endl;
   clog << "test for clog" << endl;
   TestWide( );
}

Input

3
1

Sample Output

Enter a number: 3
test for cerr
test for clog
Enter a number: 1
test for wcerr
test for wclog

Requirements

Header: <iostream>

Namespace: std

See Also

Concepts

<iostream> Members

ostream

iostream Programming

iostreams Conventions