void test_copy_binary(std::string src,std::string dst){
std::ofstream ostrm(dst,std::ios::binary);
std::ifstream istrm(src,std::ios::binary);
if (!istrm.is_open() )
    {
        std::cout<<"failed to open: "<<src<<std::endl;
return ;
    }
if (!ostrm.is_open())
    {
        std::cout<<"failed to open: "<<dst<<std::endl;
return ;
    }
    {
char buf[1];
while(1){
            istrm.read(buf,1);
if(istrm.eof())
            {
break;
            }
            ostrm.write(buf,1);
            istrm.seekg(1024);
        }
        istrm.close();
        ostrm.close();
    }
}