Hello, I am trying to implement some new composed operations (like boost::asio::async_read) with asio. However I am a bit concerned about thread-safety when the run-method of the used io_service object ist called from multiple threads and there are parallel read- and write operations on the same socket. The composed operations look like this: class io_port { public: //Ctors and so on... typedef boost::function<void (error_t const &)> completion_handler_t; void async_read_data ( raw_buffer_t & buffer , completion_handler_t const & handler) { //uses a composed operation itself... boost::asio::async_read ( socket , boost::asio::buffer(header) , boost::bind ( &io_port::handle_header_received , this , boost::ref(buffer) , handler , boost::asio::placeholders::error) ); } //first intermediate handler void handle_header_received ( raw_buffer_t & data , completion_handler_type const & handler , boost::system::error_code const & error { if(error) { handler(error_t(error)); } else { prepare_buffer(data, header.perparation_data()); //pseudo-code //uses a composed operation itself... boost::asio::async_read ( socket , boost::asio::buffer(data) , boost::bind ( &io_port::handle_data_received , this , boost::ref(buffer) , handler , boost::asio::placeholders::error) ); } } //second intermediate handler void handle_data_received ( raw_buffer_t & data , completion_handler_type const & handler , boost::system::error_code const & error ) { if(error) { handler(error_t(error)); } else { handler(error_t()); } } void async_write_data ( raw_buffer_t const & buffer , completion_handler_t const & handler) { ... } //quite similar to async_read_data }; usage may be either port.async_read ( buffer , handler ); or port.async_read ( buffer , strand.wrap(handler) ); //how to forward this to asio::async_read? If async_write_data is called and io_service::run is called from multiple threads, strands are should be necessary to avoid raced. The question is: How do I support handlers wrapped in a strand and how do I get this strand forwarded to async_read? As far as I understand this should be somehow possible by using asio_handler_invoke but the documentation is a bit too fuzzy on the topic for me to understand. -- Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de