#include <fstream>
#include <vector>
#include <iterator>

int main()
{
    std::ifstream ifs("test.txt");
    ifs.unsetf(std::ios::skipws);
    std::vector<char> buf(
        (std::istream_iterator<char>(ifs)),
         std::istream_iterator<char>());
    std::ofstream ofs("testcopy.txt", std::ios::binary);
    ofs.write(buf.data(), buf.size());
}