c++ - boost::bind member function WriteHandlerCheck error -

i'm trying bind function boost::asio::async_write, got semantic error in write.hpp

class client{   public:     client(const int &frame_,char* buf,const int& size_){     frame=frame_;     b=buf;     size=size_;   }    void donothing(){       //?   }    void handle(const boost::system::error_code& error,std::size_t bytes_transferred ){       //should handle socket being closed , data in buffer being released       cout<<"bytes sent: "<<bytes_transferred<<endl;       cout<<error<<endl;   }     void runclient()   {     try     {          tcp::resolver resolver(io_service);         tcp::resolver::query query(tcp::v4(), host, port);         tcp::resolver::iterator iterator = resolver.resolve(query);         s=new boost::asio::ip::tcp::socket(io_service);         boost::asio::connect(*s, iterator);           std::cout << "sending png: frame"<<frame<<" size: "<<size<<"bytes ... "<<endl;          int number_to_send = size; // put value         int converted_number = htonl(number_to_send);         boost::asio::async_write(*s,boost::asio::buffer(&converted_number, sizeof(converted_number)),&client::donothing);          boost::asio::async_write(*s, boost::asio::buffer(b, size),                                  boost::bind(&client::handle,                                              this,                                              boost::asio::placeholders::error,                                              boost::asio::placeholders::bytes_transferred));          std::cout << "done!"<<endl;       }       catch (std::exception& e)       {         std::cerr << "exception: " << e.what() << "\n";       }   }    private:     enum { max_length = 1024 };     string port="1112";     string host="157.193.215.48";     char * b;     int size;     int frame;     boost::asio::io_service io_service;     boost::asio::ip::tcp::socket* s;  }; 

this code has no syntax errors, give error in write.hpp when compiling:

/usr/local/include/boost/asio/impl/write.hpp:615:3:    called object type 'void (client::*)()' not function or function pointer. 

affected code:

template <typename asyncwritestream, typename constbuffersequence,     typename writehandler> inline boost_asio_initfn_result_type(writehandler,     void (boost::system::error_code, std::size_t)) async_write(asyncwritestream& s, const constbuffersequence& buffers,     boost_asio_move_arg(writehandler) handler) {   // if error on following line means handler   // not meet documented type requirements writehandler.   boost_asio_write_handler_check(writehandler, handler) type_check;    detail::async_result_init<     writehandler, void (boost::system::error_code, std::size_t)> init(       boost_asio_move_cast(writehandler)(handler));    detail::write_op<asyncwritestream, constbuffersequence,     detail::transfer_all_t, boost_asio_handler_type(       writehandler, void (boost::system::error_code, std::size_t))>(         s, buffers, transfer_all(), init.handler)(           boost::system::error_code(), 0, 1);    return init.result.get(); } 

affected line:

// if error on following line means handler // not meet documented type requirements writehandler. boost_asio_write_handler_check(writehandler, handler) type_check; 

it's obvious there's wrong handlers, both of them. can't find out , i'm getting annoyed it.

in first async write, send pointer non static member function without having binded pointer did in second write.

    boost::asio::async_write(*s,boost::asio::buffer(&converted_number, sizeof(converted_number)),&client::donothing); 

should be

    boost::asio::async_write(*s,boost::asio::buffer(&converted_number, sizeof(converted_number)),boost::bind(&client::donothing,this));