very basic c++ question hopefully

[kdubs]

Okay, so I am doing a project for my beginning C++ course, and I'm not
too familiar with file I/O. Here is my code so far.

--------beginning-------
char filename[20];
//user output/input
cout << "please enter the name of a file for output\n";
cout << "(20 character max):";
cin >> filename;
ofstream outStream;
outStream.open(filename);
------end------

how do i write this file as a .txt without causing hell?? is there a
different way I can rewrite this, because when i write this, it just
creates the file as whatever the user inputs, and if I put "" around
the filename, it nullifies the users input....

please help!

[Gianni Mariani]

kdubs wrote:

Okay, so I am doing a project for my beginning C++ course, and I'm not
too familiar with file I/O. Here is my code so far.

--------beginning-------
char filename[20];
//user output/input
cout << "please enter the name of a file for output\n";
cout << "(20 character max):";
cin >> filename;
ofstream outStream;
outStream.open(filename);
Place this line at the top of your file
#include <string>

Replace this:
char filename[20];

with:
std::string filename;

AND NEVER EVER read from a file in an unconditional way into a fixed
length array like that ever again. This construct allows for "buffer
overflow" and is the main cause for your Internet Exploder security
breaches. It may be a bit early to introduce you to that concept but
security IS A BIG issue.

Then you can add your favorite file suffix.
outStream.open(filename+".txt");


------end------

how do i write this file as a .txt without causing hell?? is there a
different way I can rewrite this, because when i write this, it just
creates the file as whatever the user inputs, and if I put "" around
the filename, it nullifies the users input....

please help!

[mlimber]

Gianni Mariani wrote:

kdubs wrote:

Okay, so I am doing a project for my beginning C++ course, and I'm not
too familiar with file I/O. Here is my code so far.

--------beginning-------
char filename[20];
//user output/input
cout << "please enter the name of a file for output\n";
cout << "(20 character max):";
cin >> filename;
ofstream outStream;
outStream.open(filename);

Place this line at the top of your file
#include <string>

Replace this:
char filename[20];

with:
std::string filename;

AND NEVER EVER read from a file in an unconditional way into a fixed
length array like that ever again. This construct allows for "buffer
overflow" and is the main cause for your Internet Exploder security
breaches. It may be a bit early to introduce you to that concept but
security IS A BIG issue.

Then you can add your favorite file suffix.
outStream.open(filename+".txt");

You'll need to convert that to a C-style string:

filename += ".txt";
ofstream outStream( filename.c_str() );

Cheers! --M

[kdubs]

thank you all...