Re: encryption problem
On Jul 29, 3:50 am, Kai-Uwe Bux <jkherci...@gmx.net> wrote:
BobR wrote:
Juha Nieminen <nos...@thanks.invalid> wrote in message...
cout << "text: "; // enter some text
cin >> plain_text; file://assign the array of text to plain_text
Here is the critical point. What happens if the user enters more
than 80 characters?
You don't want to do that. You want to do this:
std::string plainText;
std::cout << "text: ";
std::getline(std::cin, plainText);
Now it doesn't matter how much text the user writes. It won't cause
a buffer overflow.
Well, it will:
plainText.max_size() == 1073741820 [Intel, win98, MinGW].
Not too many people type that much into one line though. <G>
[ at the old (80 char line) x (66 lines per page), thats over200k pages.
So, be sure to tell your users to limit the input to "one book per line=
"!
:-} ]
No, it won't cause a buffer overflow. Instead, getline() will
stop after max_size() characters and then set the failbit of
the stream. [21.3.7.9/6]
Unless, of course, bad_alloc gets thrown before that:-). Or the
machine starts paging so violently that it slows down radically,
and pisses the user off so much that he kills the process.
--
James Kanze (Gabi Software) email: james.kanze@gmail.com
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