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Groups > comp.lang.c++ > #6215

Persisting a structure: Valgrind errors

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Hello,

Though I have a good amount of experience in ANSI C, Java, C#...etc, I 
am fairly new with C++.

What I am trying to do is to persist a struct to a binary file.  The 
structure is being saved correctly yet when I am trying to load it from 
disk to memory Valgrind is popping up some errors (Invalid write and 
Invalid free) from this line of code:

file.read((char*) i, sizeof(struct record));

Attached with this message is the code of my program.  Can anyone point 
out what am I doing wrong?  Mind you, the program runs great, just 
Valgrind is showing some warnings.

Thanks.

//
// code
//

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

#define NAME "test_file.bin"


struct record
{
	string	name;
	string	surname;
};


void save(struct record *i)
{
	fstream file;
	
	file.open(NAME, fstream::trunc | fstream::binary | fstream::out);
	
	
	if (!file.is_open())
		throw string("Unable to open file");
	
	file.write((char*)i, sizeof(struct record));
	
	file.close();
}




void load(struct record *i)
{
	fstream 		file;
	
	file.open(NAME, fstream::binary | fstream::in);
	
	
	if (!file.is_open())
		throw string("Unable to open file");
	
	
  	file.read((char*) i, sizeof(struct record));	// error
	
	file.close();
}




int main()
{
	struct record *r = new struct record;
	struct record *test = new struct record;
	
	r->name = "name";
	r->surname = "surname";
	
	save(r);
  	load(test);
  	
   	cout << test->name << endl;
   	cout << test->surname << endl;
	
	delete r;
	delete test;
	
	return 0;
}

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Thread

Persisting a structure:  Valgrind errors Ramon <ramif_47.invalid@yahoo.co.uk> - 2011-06-04 23:19 +0200
  Re: Persisting a structure:  Valgrind errors Ian Collins <ian-news@hotmail.com> - 2011-06-05 10:59 +1200
    Re: Persisting a structure: Valgrind errors Ebenezer <woodbrian77@gmail.com> - 2011-06-04 18:11 -0700
      Re: Persisting a structure: Valgrind errors Öö Tiib <ootiib@hot.ee> - 2011-06-04 18:56 -0700
  Re: Persisting a structure:  Valgrind errors Juha Nieminen <nospam@thanks.invalid> - 2011-06-05 05:57 +0000
    Re: Persisting a structure:  Valgrind errors "io_x" <a@b.c.invalid> - 2011-06-05 08:14 +0200
      Re: Persisting a structure:  Valgrind errors Ramon <ramif_47.invalid@yahoo.co.uk> - 2011-06-05 11:40 +0200
        Re: Persisting a structure:  Valgrind errors "io_x" <a@b.c.invalid> - 2011-06-05 12:17 +0200
          Re: Persisting a structure:  Valgrind errors Ramon <ramif_47.invalid@yahoo.co.uk> - 2011-06-05 18:15 +0200
            Re: Persisting a structure:  Valgrind errors Asger-P <junk@asger-p.dk> - 2011-06-05 18:44 +0200
            Re: Persisting a structure:  Valgrind errors Juha Nieminen <nospam@thanks.invalid> - 2011-06-07 06:20 +0000
              Re: Persisting a structure: Valgrind errors Joshua Maurice <joshuamaurice@gmail.com> - 2011-06-07 00:24 -0700
                Re: Persisting a structure: Valgrind errors Juha Nieminen <nospam@thanks.invalid> - 2011-06-07 08:40 +0000
                Re: Persisting a structure: Valgrind errors Miles Bader <miles@gnu.org> - 2011-06-08 14:43 +0900
                Re: Persisting a structure: Valgrind errors Joshua Maurice <joshuamaurice@gmail.com> - 2011-06-07 23:37 -0700
                Re: Persisting a structure: Valgrind errors Miles Bader <miles@gnu.org> - 2011-06-08 17:18 +0900
        Re: Persisting a structure:  Valgrind errors Nobody <nobody@nowhere.com> - 2011-06-05 18:42 +0100
    Re: Persisting a structure: Valgrind errors Ebenezer <woodbrian77@gmail.com> - 2011-06-05 13:22 -0700
  Re: Persisting a structure:  Valgrind errors Asger-P <junk@asger-p.dk> - 2011-06-05 12:04 +0200

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