文件操作标志位出错检测

#include <iostream>
using namespace std;
#include <fstream>
#include <cstdlib>
void showState(fstream &);
int main()
{
int num=10;
fstream testFile("stuff.dat",ios::out);

if (testFile.fail())
{
cout << "文件打开失败";
exit(0);
}
cout << "向文件中写入数据" << endl;
testFile << num;
showState(testFile);
testFile.close();
testFile.open("stuff.dat",ios::in);
if (testFile.fail())
{
cout << "打开文件失败";
exit(0);
}
cout << "从文件中读一个整数" << endl;
testFile >> num;
showState(testFile);
cout << "再读一个整数" << endl;
testFile >> num;
showState(testFile);
testFile.close();
return 0;
}

void showState(fstream &file)
{
cout << "当前文件的状态位置如下:" <<endl;
cout << " eof bit:" << file.eof() << " ";
cout << " fail bit:" << file.fail() << " ";
cout << " bad bit:" << file.bad() << " ";
cout << "good bit:" << file.good() << " " << endl;
file.clear();
}