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Start an asynchronous receive.
template< typename MutableBufferSequence, typename ReadToken = default_completion_token_t<executor_type>> DEDUCED async_receive( const MutableBufferSequence & buffers, socket_base::message_flags flags, ReadToken && token = default_completion_token_t< executor_type >());
This function is used to asynchronously receive data from the stream socket. It is an initiating function for an asynchronous operation, and always returns immediately.
One or more buffers into which the data will be received. Although the buffers object may be copied as necessary, ownership of the underlying memory blocks is retained by the caller, which must guarantee that they remain valid until the completion handler is called.
Flags specifying how the receive call is to be made.
                  The completion
                  token that will be used to produce a completion handler,
                  which will be called when the receive 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( const asio::error_code& error, // Result of operation. std::size_t bytes_transferred // Number of bytes received. );
                  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, std::size_t)
            The receive operation may not receive all of the requested number of
            bytes. Consider using the async_read function if you need
            to ensure that the requested amount of data is received before the asynchronous
            operation completes.
          
            To receive into a single data buffer use the buffer function as follows:
          
socket.async_receive(asio::buffer(data, size), 0, handler);
            See the buffer
            documentation for information on receiving into multiple buffers in one
            go, and how to use it with arrays, boost::array or std::vector.
          
            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