Start an asynchronous send.
template< typename ConstBufferSequence, typename WriteHandler> void-or-deduced async_send_to( const ConstBufferSequence & buffers, const endpoint_type & destination, socket_base::message_flags flags, WriteHandler handler);
This function is used to asynchronously send a datagram to the specified remote endpoint. The function call always returns immediately.
One or more data buffers to be sent to the remote endpoint. 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 handler is called.
Flags specifying how the send call is to be made.
The remote endpoint to which the data will be sent. Copies will be made of the endpoint as required.
The handler to be called when the send operation completes. Copies will be made of the handler as required. The function signature of the handler must be:
void handler( const boost::system::error_code& error, // Result of operation. std::size_t bytes_transferred // Number of bytes sent. );
Regardless of whether the asynchronous operation completes immediately
or not, the handler will not be invoked from within this function.
Invocation of the handler will be performed in a manner equivalent