whose the c++ wizard

my objective is to simply read in characters and store it in a multidimensional character array.

file format .. 50 lines of 80 characters
example
155157JOHN Q. PUBLIC 00015787
155238HELEN GONE 00015687

trying to read from a employee.dat file until the end of file, but keeps on getting segmentation error.

int main()
{
ifstream data;
char string[80];
char s1[50][80];
int i=0;

data.open("c:/employee.dat",ios::in);

if(!data)
{
cerr << "file cannot be opened! " << endl;
exit(1);
}

while(!data.eof())
{
data.get(string,80,'\n');
strcpy(s1[i],string);
cout << s1[i] << endl;
i++;
}

data.close();

return(0);
}

Three things:

1. I believe the segmentation error came from the fact that you used a forward slash after "c:" instead of a backward slash, because it worked after I changed it to a backward slah.

2. I'm not sure if I'm doing something wrong, but the program didn't seem to want to open "c:\employees.dat", because I believe root directory used in a filestream is the folder that the file is in. Therefore, just put the .dat file in the same place as the program.

3. The program did not work for reading in the lines properly when I test-drove it. I added a .ignore function, which seems to have cleared it up.

Anyways, here's what it looks like; this should work:

Code:

int main()
{

    ifstream data;
       
    char string[80];
    char s1[50][80];

    data.open("employee.dat", ios::in);

    if(!data) 
    { 

        cerr << "File cannot be opened!" << endl;
        system("PAUSE");

    } 

    for (int i = 0; !data.eof(); i++)
    { 

        data.get(string,80,'\n'); 

        strcpy(s1[i],string); 

        cout << s1[i] << endl;

        data.ignore('\n', 10);

    } 

    data.close();

    system("PAUSE");

    return 0;

}

Code:

.......
if(!data) 
    { 

        cerr << "File cannot be opened!" << endl;
        system("PAUSE");
        return 0;                    // you need to exit the program or you'll get the error

    } 
........

You might wanna change this:

while(!data.eof())
{
data.get(string,80,'\n');
strcpy(s1[i],string);
cout << s1[i] << endl;
i++;
}

to this:

i=0;
data.get(string,80,'\n');
while(!data.eof())
{
strcpy(s1[i],string);
cout << s1[i] << endl;
i++;
data.get(string,80,'\n');
}


I think that .eof() checks if EOF is in the input buffer. Hence, you wanna input, make sure it isn't eof, then copy the data over. If you don't, you might get some garbage written at the end of the array.

Next time try using quotes That way everyone can read the code