Use fstream to read and write a file. : fstream « File Stream « C++ Tutorial

1. C++ Tutorial
2. File Stream
3. fstream

#include <iostream>
#include <fstream>

using namespace std;

int main()
{
  char ch;

  fstream finout("test.dat");

  if(!finout) {
    cout << "Cannot open file for output.\n";
    return 1;
  }

  for(int i=0; i < 3; ++i) finout.put('X');

  if(!finout.good()) {
    cout << "Error occurred while writing to the file.\n";
    return 1;
  }

  finout.flush();
  cout << "Here are the next ten characters: ";
  for(int i=0; i < 10; ++i) {
    finout.get(ch);
    cout << ch;
  }
  cout << endl;

  if(!finout.good()) {
    cout << "Error occurred while reading from the file.\n";
    return 1;
  }

  finout.close();

  if(!finout.good()) {
    cout << "Error occurred while closing the file.\n";
    return 1;
  }

  return 0;
}