Read a file interactively.

ReadFileI.cpp

#include <fstream>
#include <iostream>

int interactive(const std::string& path)
{
    int count{ 0 };
    char buffer[1024]{ 0 };
    std::ifstream ifs{ path };
    if (!ifs)
        return -1;

    while (!ifs.eof())
    {
        std::cout << "> ";
        std::cin >> count;

        if (count == 0) break;
        if (count < 0)
        {
            auto pos{ ifs.tellg() };
            pos += count;
            if (pos < 0) pos = 0;
            ifs.seekg(pos);
            continue;
        }

        ifs.read(buffer, count);

        long long* number{ reinterpret_cast<long long*>(buffer) };

        std::cout
            << buffer // string
            << std::endl
            << *number
            << std::endl;


        std::memset(buffer, 0, count);
    }

    ifs.close();
    return 0;
}