mqtt_client::async_disconnect (2 of 2 overloads)

Disconnect the Client by sending a DISCONNECT packet with a Reason Code of reason_codes::normal_disconnection. This function has terminal effects.

template <
    typename CompletionToken = typename asio::default_completion_token<executor_type>::type
>
decltype(auto) async_disconnect(
    CompletionToken && token = {}
);

Description

The Client will attempt to send a DISCONNECT packet to the Broker with a Reason Code describing the reason for disconnection. If the DISCONNECT packet is successfully transmitted, or if 5 seconds elapsed without a successful send, the Client will terminate the connection.

	Important
	This function has terminal effects and will close the Client. See `mqtt_client::cancel`.

Parameters

Name	Description
token	Completion token that will be used to produce a completion handler. The handler will be invoked when the operation completes.

Handler signature

The handler signature for this operation:

void (
  async_mqtt5::error_code // Result of operation.
)

Completion condition

The asynchronous operation will complete when one of the following conditions is true:

The Client has attempted to send a DISCONNECT packet, regardless of whether the sending was successful or not.
An error occurred. This is indicated by an associated async_mqtt5::error_code in the handler.

Error codes

The list of all possible error codes that this operation can finish with:

boost::system::errc::errc_t::success
boost::asio::error::operation_aborted^[10]
async_mqtt5::client::error::malformed_packet

Refer to the section on Error handling to find the underlying causes for each error code.

Per-Operation Cancellation

This asynchronous operation supports cancellation for the following boost::asio::cancellation_type values:

cancellation_type::terminal - invokes mqtt_client::cancel

^[10] This error code can appear if the Client fails to send the DISCONNECT packet to the Server. Regardless, the connection to the Server is terminated, and the Client is cancelled.