streams and files

I’m having some problems with displaying my file content correctly .

I have a program that writes an object with two member items, in binary mode, to my “person.dat” file.

Code:

#include <iostream>
#include <fstream>
#include <stdlib.h>
 class person
 {
 protected:
 char name[80];
 short age;
 public:
 void getData()
     {
      cout << "Enter name: "; cin >> name;
      cout << "Enter age: "; cin >> age;
     }
 };
int main()
{
  person pers;
  pers.getData();

  ofstream outfile ("person.dat", ios::binary);

  outfile.write(reinterpret_cast<char*>(&pers), sizeof(pers));

  cout << "finished" << endl;
  system("PAUSE");
  return 0;
}

Output
Enter name: Chad
Enter age: 24
finished


When I use another program to read this information I get very weird results.

Code:

#include <iostream>
#include <fstream>
#include <stdlib.h>
 class person
 {
 protected:
 char name[80];
 short age;
 public:
 void showData()
     {
      cout << "Name: " << name << endl;
      cout << "Age: " << age << endl;
     }
 };
int main()
{
  person pers;
  //pers.getData();

  ifstream infile ("person.dat", ios::binary);

  infile.read(reinterpret_cast<char*>(&pers), sizeof(pers));
   pers.showData();
  cout << "finished" << endl;
  system("PAUSE");
  return 0;
}

Output
Name: Hô|-wx;”
Age -96
finished


I use DevC++ to compile my sources if that helps any

NOTE: This is not a homework problem. The source code can be found in “Object-Oriented Programming in C++”, Robert Lafore, Page 592.

Works fine for me really. One thing you could try is keeping you class consistent across projects (even though member functions should not affect).

Code:

class person
{
protected:
	char name[80];
	short age;
public:
	void getData()
	{
		cout << "Enter name: "; cin >> name;
		cout << "Enter age: "; cin >> age;
	}
	void showData()
	{
		cout << "Name: " << name << "\n";
		cout << "Age: " << age << "\n";
	}
};

Also, as this is cross project, you should make sure that they are using the same .dat file See this FAQ entry about writing struct/class objects to a file: http://www.codeguru.com/forum/showthread.php?t=269648 Make sure to close() filehandles when you're done with them too.

>> #include <stdlib.h>

#include <cstdlib>

I deleted the ios::binary

Code:

ofstream outfile ("person.dat", ios::binary); 

works! -> ofstream outfile ("person.dat");

working code

Code:

#include <iostream>
#include <fstream>
#include <cstdlib>
 class person
 {
 protected:
 char name[80];
 short age;
 public:
 void getData()
     {
      cout << "Enter name: "; cin >> name;
      cout << "Enter age: "; cin >> age;
     }
 };
int main()
{
  person pers;
  pers.getData();

  ofstream outfile ("person.dat");

  outfile.write(reinterpret_cast<char*>(&pers), sizeof(pers));
  outfile.close();

  cout << "finished" << endl;
  system("PAUSE");
  return 0;
}

But why? Is it my compiler?