C / C++ / MFC

CLogBook dummy;
dummy.open("test.txt", ios_base::in | ios_base::out | ios_base::app);

// This is written to the file
dummy.ErrorCode() = 123;
dummy.ErrorMessage() = "erro error error";
dummy.Extra() = "WinMain";

dummy.SaveLogData();

// 1
dummy.close();
dummy.open("test.txt", ios_base::in | ios_base::out | ios_base::app);

string buf("");
dummy.ReadLogData(buf); // This will success

// 2
// dummy.close();
// dummy.open("test.txt", ios_base::in | ios_base::out | ios_base::app);
	
MessageBox(NULL, buf.c_str(), "", MB_OK);

// This will fail even if I try to close /open in the second place
dummy.ErrorCode() = 666;
dummy.ErrorMessage() = "yadda yadda";
dummy.Extra() = "Linux";

#include <fstream>
#include <iostream>
#include <windows.h>
#include <string>
 
using namespace std;
 
class CLogBook : public fstream
{
public:
  CLogBook(){}
  ~CLogBook(){ close(); }
  void SaveLogData()
  {
    clear();
    write(ErrorMessage().c_str(),ErrorMessage().size());
    // Your code presumably writes more stuff than this
  }
  void ReadLogData(string& data)
  { 
    seekg(0);
    while(!eof())	{
      char* temp = new char[1024];
      getline(temp, 1024, '\n');
      data.append(temp);
      data.append("\n");
      delete [] temp;
    }
  }
 
  int& ErrorCode() { return m_errorCode; };
  string& ErrorMessage() { return m_errorMessage; };
  string& Extra() { return m_extra; };
private:
  string m_errorMessage;
  int m_errorCode;
  string m_extra;
};
 
int main()
{
  CLogBook dummy;
  dummy.open("test.txt", ios_base::in | ios_base::out | ios_base::app);
  dummy.ErrorCode() = 123;
  dummy.ErrorMessage() = "Error occured in your brain.. please RTFM!";
  dummy.Extra() = "WinMain";
  dummy.SaveLogData();  // write
   
  string buf("");
  dummy.ReadLogData(buf);
  MessageBox(NULL, buf.c_str(), "", MB_OK);// this will not be written to the file!
  dummy.ErrorCode() = 666;
  dummy.ErrorMessage() = "never written words";
  dummy.Extra() = "BASIC SUCKS";
  dummy.SaveLogData();
 
  return 0;
}

wsprintf(szBuffer, "%04d%02d%02d", yyyy,mm,ddd);<br />
lDate = atol(szBuffer;

CDialogBar bar;
bar.SetWindowText("My title");

<br />
FILE* file;<br />
file = fopen("YourFile.txt", "w+"); // "w+" deletes the contents of the file<br />