带有 std::cin >> char 的 C++ 调试断言错误

Question

Background : The problem/code shown here is part of a larger program I am trying to create (I was told to trim it down). The purpose (of this section) is to be able to receive std::cin input and (when it works) feed it into the function: srcdsControl->WriteText(string(chr)); This function is part of the larger program, which I have not created myself.

I'm trying to redirect input and output from a C++ console application to a Python script (which I have written, and which works). When I type into the console window, it receives the input fine. However, when I send input to the program's stdin from python (in the format 'command\\r\\n'), it triggers the following error:

I've tried with both of the following programs and they give exactly the same error.

My C++ code (test 1):

#include "stdafx.h"
#include <iostream>
#include <string>

int main()
{
    try
    {
        char chr[2];
        chr[1] = 0;
        while (1)
        {
            if (std::cin >> std::noskipws >> chr[0])
            {
                if (chr[0] == '\r')
                    std::cout << "\r";
                //srcdsControl->WriteText(string(chr));
                std::cout << std::string(chr) << "\r\n";
            }
        }
    }
    catch (...)
    {
        // Ignore exception and just stop the thread.
    }
}

My C++ code (test 2):

#include "stdafx.h"
#include <iostream>
#include <string>

int main()
{
    try
    {
        char chr[2];
        chr[1] = 0;
        while (1)
        {
            std::string s = "";
            if (std::getline(std::cin, s))
            {
                for (char& ch : s) {
                    chr[0] = ch;
                    if (chr[0] == '\r')
                        std::cout << "\r";
                    //srcdsControl->WriteText(std::string(chr));
                    std::cout << std::string(chr) << "\r\n";
                }
            }
        }
    }
    catch (...)
    {
        // Ignore exception and just stop the thread.
    }
}

Note : I am not a C++ developer and my knowledge of C++ is very limited. I need a specific/simple answer.

My question : How do I prevent this error and ensure that the input is properly received? I am happy to use a completely different method to receive the input if needed, but would need a specific demonstration of it.

Answer 1

I somehow managed to fix my own problem.

#include "stdafx.h"
#include <iostream>
#include <string>

int main()
{
    try
    {
        char chr[2];
        chr[1] = 0;
        while (1)
        {
            char c;
            if (std::cin >> std::noskipws >> c)
            {
                chr[0] = c;
                if (chr[0] == '\r')
                    std::cout << "\r";
                //srcdsControl->WriteText(string(chr));
                std::cout << std::string(chr) << std::endl;
            }
        }
    }
    catch (...)
    {
        // Ignore exception and just stop the thread.
    }
}

This code seems to do what I want without giving the error. If anyone can explain why this works and the previous code didn't that would be interesting to know.