今天好象很倒霉的样子

随便在书上看点什么东西 都有会遇到问题

下面是潜能书上的例子，我看不出来这个cerr与 cout
的区别啊

改成cout也运行完全一样

//**********************
//** ch19_1.cpp **
//**********************

#include<iostream.h>

void fn(int a, int b)
{
if(b==0)
cerr <<"zero encountered. "
<<"The message cannot be redirected";
else
cout <<a/b <<endl;
}

void main()
{
fn(20,2);
fn(20,0);
}

请讲一讲啊
先谢谢了

[QUOTE]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
Copy Code
Enter a number: 3
test for cerr
test for clog
Enter a number: 1
test for wcerr
test for wclog
[/QUOTE]

clog:
extern ostream clog;
The object controls buffered insertions to the standard error output as a byte stream.

cout:The object controls insertions to the standard output as a byte stream.

呵呵，不用翻译了吧，很易懂的。平时多查查MSDN，很有帮助的，对英语也是一种提高哦

[此贴子已经被作者于2007-5-3 20:35:09编辑过]

#include <iostream>
using namespace std;

int main()
{
    int a,b;
    freopen(\"in.txt\",\"r\",stdin);
    freopen(\"out.txt\",\"w\",stdout);
    cin>>a>>b;
    if(b!=0){
        cout<<\"a/b=\"<<a/b<<endl;
    }
    else {
        cerr<<\"b can't be zero.\"<<endl;
    }
}

有看过的呀

你把cerr和cout换个位子试试....