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basic_datagram_socket::async_receive (1 of 2 overloads)

Start an asynchronous receive on a connected socket.

    typename MutableBufferSequence,
    typename ReadHandler = DEFAULT>
DEDUCED async_receive(
    const MutableBufferSequence & buffers,
    ReadHandler && handler = DEFAULT);

This function is used to asynchronously receive data from the datagram socket. The function call 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 handler is called.


The handler to be called when the receive 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 received.

Regardless of whether the asynchronous operation completes immediately or not, the 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.


The async_receive operation can only be used with a connected socket. Use the async_receive_from function to receive data on an unconnected datagram socket.


To receive into a single data buffer use the buffer function as follows:

socket.async_receive(boost::asio::buffer(data, size), 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.

Per-Operation Cancellation

On POSIX or Windows operating systems, this asynchronous operation supports cancellation for the following cancellation_type values: