overwrite

[xXmusicmanXx]

My program works for cout, but when I want to overwrite to the file I originally opened, nothing happens. I don't want to use append, just overwrite. I basically want to take my encoded file, read it, and print the results to the computer, which I know how to do, and back to the text file that had the encoded text (it is unscrambled when I send it back)

int main ()
{
cout << "programmer: darren sandusky " << endl;
cout << "this program decodes input text file and sends it to and output file and console " << endl;

ifstream fin;
fin.open ("secret.txt"); //reads the scrambled text. Unscrambled should show
//up back here as well after the program runs
if (!fin.good()) throw "I/O error";

ofstream fout;
fout.open ("secret.txt"); //I added this and the output shows nothing
if (!fout.good()) throw "I/O error";



while (!fin.eof())
{
int i;
string a;
fin >> a;
fin.ignore (1000, 10);
for (int i = 0;i < a.length(); i++)
a[i]--;

fout << a << endl; //this should print unscrambled to secret.txt
cout << a << endl; //this works. It prints the unscrambled version to console

}

fin.close ();
fout.close (); //fout close

return 0;
}

[Warnis]

If this is all the code I'd say it's because you never open fout

[xXmusicmanXx]

well maybe I entered it wrong but last time I included fout.open etc. it pprinted nothing...I will try again

[xXmusicmanXx]

^i opened the file, and it still prints to the console just fine. It doesn't overwrite the decoded text though in the file; it leaves what was originally there.

[Zhuge]

Can you open a file for reading and writing at the same time with two different streams?

[Mathhead200]

Did you remember to close fout?

[xXmusicmanXx]

yes. let me show you where I did it

[xXmusicmanXx]

bump.... Still not printing anything, and the logic seems right...

[Warnis]

I don't really use fstream alot but I'm going to guess its because you're both reading and writing to the same file, try changing the filename for fout to secret2.txt

[xXmusicmanXx]

I would, but the assignment says write to the same file..its tricky because that what screws with the logic...Its like trying to do too much to one file at the same time..

[get funky]

Maybe try explicitly telling it to open "secret.txt" as an output stream

fout.open( "secret.txt", ios::out );

[xXmusicmanXx]

^i tried that but nothing doing. now, if you use ios :: app, that works, but it appends, not overwrites...Also, I do the encoder everytime, so I know that there is stuff in secrets.txt to begin with..

[Warnis]

In that case how about you open them separetely, reading all of the strings into an array of strings, decoding and then writing them back to secret.txt

[xXmusicmanXx]

so track all the input as strings then? and then decode those strings, then print the decoded back to the file?

[Warnis]

Yes, unless the assignment demanded that you read/write at the same time I think it should work just fine.

[xXmusicmanXx]

thanks Warnis! I will try that and see if it works. reading/writing at the same time was the first thing that came to mind, so I will try what you suggested.

[xXmusicmanXx]

do I feel dumb.. I wasn't required to do fout this whole time! fail...