C++ Writing To File Help

[iccaros]

ok I have two c++ programs to test before makeing them into function..

I have one program that creates a file called salesinfo.txt and populates it with information.

I have a second program that reads the file and displayes its output..

my problem is.. I think the first program is not closeing the file.. I think this because I have to add examplefile.close() before I can try to read the file.

you will see where I commented out the placement of examplefile.close() in the first

#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;


int main ()
{
    int Sales;
    char record_name[32];
    ofstream examplefile ("salesinfo.txt");
   
    
    
    if (examplefile.is_open())
    {
     cout << "Sales Person name input: ";
     cin >> record_name;
     cout << "value of sales for the week: ";
     cin >> Sales;
     examplefile << record_name << " " << Sales;
     
}    
 examplefile.close();

     return 0;
     }
     
                              
    

program two

#include <iostream>
#include <fstream>

#include <iomanip>

using namespace std;

int main ()
{
    int Sales;
    char record_name[8]; 
    
    ifstream examplefile ("salesinfo.txt");
    examplefile.close();
    examplefile.open ("salesinfo.txt");
    if ( !examplefile )
    {cout << "Error opening file";
     exit (1);}
     
     while ( ! examplefile.eof())
     {
           //examplefile.get (record_name, 8);
           examplefile >>  record_name >> Sales >> ws;
           cout << record_name << " " << "$" << Sales << endl;
           }
           
           examplefile.close();
           
           return 0;
           
           
           }

[jcl]

They work fine here, with or without the calls to close()

~/src/bt $ grep close first.cc second.cc 
~/src/bt $ g++ -o first first.cc 
~/src/bt $ g++ -o second second.cc 
~/src/bt $ ./first 
Sales Person name input: foo
value of sales for the week: 12
~/src/bt $ ./second 
foo $12
~/src/bt $

The files are closed implicitly when the program exits, by the fstream dtor, the runtime cleanup code, or the kernel, so there shouldn't be a problem if they're separate programs. In a single program you'd have to verify that a single file can opened and manipulated via two different streams pointing in different directions. I'll check the standard when I have a chance. Of course you can use a single fstream is that it a problem.

[iccaros]

so in the second one you took out line 14 examplefile.close();

and it still workded (I thought I had taken it out before..)

I guess it does not matter since I am putting them in the same program and will read a write so I have to close the file before reading..