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Start an asynchronous accept.
template< typename Executor1, typename MoveAcceptToken = default_completion_token_t<executor_type>> DEDUCED async_accept( const Executor1 & ex, MoveAcceptToken && token = default_completion_token_t< executor_type >(), constraint_t< is_executor< Executor1 >::value||execution::is_executor< Executor1 >::value > = 0);
This function is used to asynchronously accept a new connection. It is an initiating function for an asynchronous operation, and always returns immediately.
This overload requires that the Protocol template parameter satisfy the AcceptableProtocol type requirements.
The I/O executor object to be used for the newly accepted socket.
                  The completion
                  token that will be used to produce a completion handler,
                  which will be called when the accept completes. Potential completion
                  tokens include use_future, use_awaitable, yield_context, or a function
                  object with the correct completion signature. The function signature
                  of the completion handler must be:
                
void handler( // Result of operation. const asio::error_code& error, // On success, the newly accepted socket. typename Protocol::socket::template rebind_executor< Executor1>::other peer );
                  Regardless of whether the asynchronous operation completes immediately
                  or not, the completion handler will not be invoked from within
                  this function. On immediate completion, invocation of the handler
                  will be performed in a manner equivalent to using post.
                
void(asio::error_code, typename Protocol::socket::template rebind_executor< Executor1>::other))
void accept_handler(const asio::error_code& error, asio::ip::tcp::socket peer) { if (!error) { // Accept succeeded. } } ... asio::ip::tcp::acceptor acceptor(my_context); ... acceptor.async_accept(my_context2, accept_handler);
            On POSIX or Windows operating systems, this asynchronous operation supports
            cancellation for the following cancellation_type values:
          
cancellation_type::terminal
              cancellation_type::partial
              cancellation_type::total