文件为空？

xggabc

#include <iostream>
#include <fstream>
using namespace std;
main()
{
//fstream inout("D:\\xgg.txt",ios::in|ios::app,filebuf:penprotread|filebuf::sh_write);
// fstream inout("D:\abc.txt",ios_base::in);
//fstream str;
        int cnt=0;
char ch;
fstream inout("D:\\xgg.txt",ios::in|ios::app);

//str.open("D:\\xgg.txt",ios::in|ios::app);
// if(!inout.is_open())
if(!inout)
  cout<<"begin fail"<<endl;


inout.seekg(0);
while(inout.get(ch))
{
  cout.put(ch);
  cnt++;
  if(ch=='\n')
  {
  ios::pos_type mark=inout.tellg();
   //int mark=inout.tellg();
   inout<<cnt<<' ';
   inout.seekg(mark);
   //file://inout.put(' ');
  }
}

inout.clear();
inout<<cnt<<endl;
cout<<"cnt : "<<cnt<<endl;
return 0;

}

但是inout居然为空
为什么会这样
怎么改？