# include<iostream>
# include<fstream>
using namespace std;

void main(){
   ofstream out;

   out.open("grade",ios::out,filebuf::sh_compat);
   out<<"C++"<<" "<<89.5<<endl;
   out<<"English"<<" "<<93.5<<endl;
   out<<"Maths"<<" "<<87<<endl;
   out.close();
}
编译后：
Compiling...
FIO.CPP
F:\vc++\vc++程序\MyObject\FIOStreamObject\FIO.CPP(8) : error C2039: 'sh_compat' : is not a member of 'basic_filebuf<char,struct std::char_traits<char> >'
F:\vc++\vc++程序\MyObject\FIOStreamObject\FIO.CPP(8) : error C2065: 'sh_compat' : undeclared identifier
执行 cl.exe 时出错.
FIOStreamObject.exe - 1 error(s), 0 warning(s)

我查msdn的时候open()函数里面的确有三个参数也，怎么会出现这样的错误呢？