MQTTAgent_Disconnect

MQTTStatus_t MQTTAgent_Disconnect( const MQTTAgentContext_t * pMqttAgentContext,
                                   MQTTAgentDisconnectArgs_t * pDisconnectArgs,
                                   const MQTTAgentCommandInfo_t * pCommandInfo );

Add a command to disconnect an MQTT connection.

Note

MQTTAgent_CommandLoop will return after processing a DISCONNECT command to allow the network connection to be disconnected. However, any pending commands in the queue, as well as those waiting for an acknowledgment, will NOT be terminated.

The MQTTAgent_Disconnect function is provided to give a thread safe equivalent to the MQTT_Disconnect API. However, if the agent task is responsible for creating the MQTT connection (before calling MQTTAgent_CommandLoop()), then it is RECOMMENDED that an application task (i.e. a task other than the agent task) use MQTTAgent_Terminate to terminate the command loop in the agent, and the agent task be responsible for disconnecting the MQTT connection.

Parameters

[in]	pMqttAgentContext	The MQTT agent to use.
[in]	pDisconnectArgs	Optional disconnect arguments including v5 properties and reason code.
[in]	pCommandInfo	The information pertaining to the command, including: cmdCompleteCallback Optional callback to invoke when the command completes. pCmdCompleteCallbackContext Optional completion callback context. blockTimeMs The maximum amount of time in milliseconds to wait for the command to be posted to the MQTT agent, should the agent's event queue be full. Tasks wait in the Blocked state so don't use any CPU time.

Note

The context passed to the callback through pCmdContext member of pCommandInfo parameter MUST remain in scope at least until the callback has been executed by the agent task.

Returns

#MQTTSuccess if the command was posted to the MQTT agent's event queue. Otherwise an enumerated error code.

Example

// Variables used in this example.
MQTTAgentContext_t agentContext;
MQTTStatus_t status;
MQTTAgentCommandInfo_t commandInfo = { 0 };
 
// Function for command complete callback.
void disconnectCmdCallback( MQTTAgentCommandContext_t * pCmdCallbackContext,
                            MQTTAgentReturnInfo_t * pReturnInfo );
 
// Fill the command information.
commandInfo.cmdCompleteCallback = disconnectCmdCallback;
commandInfo.blockTimeMs = 500;
 
status = MQTTAgent_Disconnect( &agentContext, &commandInfo );
 
if( status == MQTTSuccess )
{
  // Command for closing the MQTT connection has been queued.
  // The MQTT disconnection event will be notified through the
  // invocation of disconnectCmdCallback().
}