将文件全部读出来，再全部写到另一个文件

	std::ifstream file("test.bin", std::ios_base::binary);//省略in
    file.seekg(0, std::ios_base::end);//移动到文件末尾
    unsigned long size = static_cast<unsigned long>(file.tellg());//获取文件大小
    file.seekg(0, std::ios_base::beg);//移动到文件开始
    char* bmp = new char[size];
    file.read(bmp, size);
    file.close();

    std::ofstream file2("test_2.bin", std::ios_base::binary);//省略out
    file2.write(bmp, size);
    file2.close();