Continuting input after end of file

Question

Is there any way that I can continue input after end of file or invalid input. The record function will throw an exception if a certain data member is not recorded. I want to catch the exception and use another function rerecord to enter the information. The program will catch the exception and print the output but it won't do the last part.

int main()
{
    info person;
    try {
        person.record(std::cin);
    }
    catch(std::domain_error e) {
        std::cout << "Re-enter person info" << std::endl;
        person.rerecord(std::cin);
    }
}

How about using `clear(eofbit)` When you found the EOF ie, reset the stream — Rahul Tripathi, Nov 05 '13 at 18:15
Also If you don't want to terminate the input stream, just don't press Ctrl+D! — Rahul Tripathi, Nov 05 '13 at 18:17
I should have been more clear. It's not just ctrl-D. The exception will be caught when input fails. But will not execute the last line. — Mars, Nov 05 '13 at 18:27
possible duplicate of [Recover stdin from eof in C](http://stackoverflow.com/questions/19744423/recover-stdin-from-eof-in-c) — hyde, Nov 05 '13 at 18:29
@RahulTripathi. Do you mean `std::cin.clear()`? Or do I negate `eofbit`. `~eofbit`. — Mars, Nov 05 '13 at 18:30

score 0 · Answer 1 · edited May 23 '17 at 12:21

0

I think some input operation failed in person.record(std::cin); and cin is in a bad state. In this case "How do I flush the cin buffer?" should help. Especially, note the call to ignore(...) to get ride of the bad input!

Running code for demo:

#include <iostream>
#include <limits>

int main() {
    int i;

    std::cout << "Input: ";

    std::cin >> i;

    std::cout << "Received: " << i << "\nInput next:";

    std::cin.clear();
    std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');

    std::cin >> i;

    std::cout << "Received: " << i << "\n";

    return 0;
}

edited May 23 '17 at 12:21

Community

1
1

answered Nov 05 '13 at 18:51

Tobias

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If I hit Ctrl-D at the first input, std::cin.clear() does not remove EOF. If I repeat `std::cin.clear()` after ignore, EOF is actually removed from the flags, but cin doesn't input anything anymore. (g++ (Debian 10.2.1-6) 10.2.1 20210110) – Ale Mar 28 '22 at 17:45

Continuting input after end of file

1 Answers1