MQTT client. More...
#include "core/net.h"#include "mqtt/mqtt_common.h"#include "core/crypto.h"#include "tls.h"#include "web_socket/web_socket.h"Go to the source code of this file.
| Data Structures | |
| struct | MqttClientWillMessage | 
| Will message.  More... | |
| struct | MqttClientCallbacks | 
| MQTT client callback functions.  More... | |
| struct | MqttClientSettings | 
| MQTT client settings.  More... | |
| struct | _MqttClientContext | 
| MQTT client context.  More... | |
| Macros | |
| #define | MQTT_CLIENT_SUPPORT ENABLED | 
| #define | MQTT_CLIENT_TLS_SUPPORT DISABLED | 
| #define | MQTT_CLIENT_WS_SUPPORT DISABLED | 
| #define | MQTT_CLIENT_DEFAULT_KEEP_ALIVE 0 | 
| #define | MQTT_CLIENT_DEFAULT_TIMEOUT 20000 | 
| #define | MQTT_CLIENT_MAX_HOST_LEN 32 | 
| #define | MQTT_CLIENT_MAX_URI_LEN 16 | 
| #define | MQTT_CLIENT_MAX_ID_LEN 23 | 
| #define | MQTT_CLIENT_MAX_USERNAME_LEN 16 | 
| #define | MQTT_CLIENT_MAX_PASSWORD_LEN 16 | 
| #define | MQTT_CLIENT_MAX_WILL_TOPIC_LEN 16 | 
| #define | MQTT_CLIENT_MAX_WILL_PAYLOAD_LEN 16 | 
| #define | MQTT_CLIENT_BUFFER_SIZE 1024 | 
| #define | MQTT_CLIENT_PRIVATE_CONTEXT | 
| #define | MqttClientContext struct _MqttClientContext | 
| Typedefs | |
| typedef void(* | MqttClientConnAckCallback) (MqttClientContext *context, uint8_t connectAckFlags, uint8_t connectReturnCode) | 
| CONNACK message received callback.  More... | |
| typedef void(* | MqttClientPublishCallback) (MqttClientContext *context, const char_t *topic, const uint8_t *message, size_t length, bool_t dup, MqttQosLevel qos, bool_t retain, uint16_t packetId) | 
| PUBLISH message received callback.  More... | |
| typedef void(* | MqttClientPubAckCallback) (MqttClientContext *context, uint16_t packetId) | 
| PUBACK message received callback.  More... | |
| typedef void(* | MqttClientPubRecCallback) (MqttClientContext *context, uint16_t packetId) | 
| PUBREC message received callback.  More... | |
| typedef void(* | MqttClientPubRelCallback) (MqttClientContext *context, uint16_t packetId) | 
| PUBREL message received callback.  More... | |
| typedef void(* | MqttClientPubCompCallback) (MqttClientContext *context, uint16_t packetId) | 
| PUBCOMP message received callback.  More... | |
| typedef void(* | MqttClientSubAckCallback) (MqttClientContext *context, uint16_t packetId) | 
| SUBACK message received callback.  More... | |
| typedef void(* | MqttClientUnsubAckCallback) (MqttClientContext *context, uint16_t packetId) | 
| UNSUBACK message received callback.  More... | |
| typedef void(* | MqttClientPingRespCallback) (MqttClientContext *context) | 
| PINGRESP message received callback.  More... | |
| typedef error_t(* | MqttClientTlsInitCallback) (MqttClientContext *context, TlsContext *tlsContext) | 
| TLS initialization callback.  More... | |
| Enumerations | |
| enum | MqttClientState { MQTT_CLIENT_STATE_DISCONNECTED = 0, MQTT_CLIENT_STATE_CONNECTING = 1, MQTT_CLIENT_STATE_CONNECTED = 2, MQTT_CLIENT_STATE_IDLE = 3, MQTT_CLIENT_STATE_SENDING_PACKET = 4, MQTT_CLIENT_STATE_PACKET_SENT = 5, MQTT_CLIENT_STATE_WAITING_PACKET = 6, MQTT_CLIENT_STATE_RECEIVING_PACKET = 7, MQTT_CLIENT_STATE_PACKET_RECEIVED = 8, MQTT_CLIENT_STATE_DISCONNECTING = 9 } | 
| MQTT client states.  More... | |
| Functions | |
| error_t | mqttClientInit (MqttClientContext *context) | 
| Initialize MQTT client context.  More... | |
| void | mqttClientInitCallbacks (MqttClientCallbacks *callbacks) | 
| Initialize callback structure.  More... | |
| error_t | mqttClientRegisterCallbacks (MqttClientContext *context, const MqttClientCallbacks *callbacks) | 
| Register MQTT client callbacks.  More... | |
| error_t | mqttClientSetVersion (MqttClientContext *context, MqttVersion version) | 
| Set the MQTT protocol version to be used.  More... | |
| error_t | mqttClientSetTransportProtocol (MqttClientContext *context, MqttTransportProtocol transportProtocol) | 
| Set the transport protocol to be used.  More... | |
| error_t | mqttClientRegisterTlsInitCallback (MqttClientContext *context, MqttClientTlsInitCallback callback) | 
| Register TLS initialization callback function.  More... | |
| error_t | mqttClientRegisterPublishCallback (MqttClientContext *context, MqttClientPublishCallback callback) | 
| Register publish callback function.  More... | |
| error_t | mqttClientSetTimeout (MqttClientContext *context, systime_t timeout) | 
| Set communication timeout.  More... | |
| error_t | mqttClientSetKeepAlive (MqttClientContext *context, uint16_t keepAlive) | 
| Set keep-alive value.  More... | |
| error_t | mqttClientSetHost (MqttClientContext *context, const char_t *host) | 
| Set the domain name of the server (for virtual hosting)  More... | |
| error_t | mqttClientSetUri (MqttClientContext *context, const char_t *uri) | 
| Set the name of the resource being requested.  More... | |
| error_t | mqttClientSetIdentifier (MqttClientContext *context, const char_t *clientId) | 
| Set client identifier.  More... | |
| error_t | mqttClientSetAuthInfo (MqttClientContext *context, const char_t *username, const char_t *password) | 
| Set authentication information.  More... | |
| error_t | mqttClientSetWillMessage (MqttClientContext *context, const char_t *topic, const void *message, size_t length, MqttQosLevel qos, bool_t retain) | 
| Specify the Will message.  More... | |
| error_t | mqttClientBindToInterface (MqttClientContext *context, NetInterface *interface) | 
| Bind the MQTT client to a particular network interface.  More... | |
| error_t | mqttClientConnect (MqttClientContext *context, const IpAddr *serverIpAddr, uint16_t serverPort, bool_t cleanSession) | 
| Establish connection with the MQTT server.  More... | |
| error_t | mqttClientSetPacketId (MqttClientContext *context, uint16_t packetId) | 
| Set packet identifier.  More... | |
| error_t | mqttClientPublish (MqttClientContext *context, const char_t *topic, const void *message, size_t length, MqttQosLevel qos, bool_t retain, uint16_t *packetId) | 
| Publish message.  More... | |
| error_t | mqttClientPublishEx (MqttClientContext *context, const char_t *topic, const void *message, size_t length, bool_t dup, MqttQosLevel qos, bool_t retain, uint16_t *packetId) | 
| Publish message.  More... | |
| error_t | mqttClientSubscribe (MqttClientContext *context, const char_t *topic, MqttQosLevel qos, uint16_t *packetId) | 
| Subscribe to topic.  More... | |
| error_t | mqttClientUnsubscribe (MqttClientContext *context, const char_t *topic, uint16_t *packetId) | 
| Unsubscribe from topic.  More... | |
| error_t | mqttClientPing (MqttClientContext *context, systime_t *rtt) | 
| Send ping request.  More... | |
| error_t | mqttClientTask (MqttClientContext *context, systime_t timeout) | 
| Process MQTT client events.  More... | |
| error_t | mqttClientDisconnect (MqttClientContext *context) | 
| Gracefully disconnect from the MQTT server.  More... | |
| error_t | mqttClientClose (MqttClientContext *context) | 
| Close the connection with the MQTT server.  More... | |
| void | mqttClientDeinit (MqttClientContext *context) | 
| Release MQTT client context.  More... | |
| error_t | mqttClientProcessEvents (MqttClientContext *context, systime_t timeout) | 
| Process MQTT client events.  More... | |
Detailed Description
MQTT client.
License
SPDX-License-Identifier: GPL-2.0-or-later
Copyright (C) 2010-2025 Oryx Embedded SARL. All rights reserved.
This file is part of CycloneTCP Open.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- Version
- 2.5.4
Definition in file mqtt_client.h.
Macro Definition Documentation
◆ MQTT_CLIENT_BUFFER_SIZE
| #define MQTT_CLIENT_BUFFER_SIZE 1024 | 
Definition at line 124 of file mqtt_client.h.
◆ MQTT_CLIENT_DEFAULT_KEEP_ALIVE
| #define MQTT_CLIENT_DEFAULT_KEEP_ALIVE 0 | 
Definition at line 61 of file mqtt_client.h.
◆ MQTT_CLIENT_DEFAULT_TIMEOUT
| #define MQTT_CLIENT_DEFAULT_TIMEOUT 20000 | 
Definition at line 68 of file mqtt_client.h.
◆ MQTT_CLIENT_MAX_HOST_LEN
| #define MQTT_CLIENT_MAX_HOST_LEN 32 | 
Definition at line 75 of file mqtt_client.h.
◆ MQTT_CLIENT_MAX_ID_LEN
| #define MQTT_CLIENT_MAX_ID_LEN 23 | 
Definition at line 89 of file mqtt_client.h.
◆ MQTT_CLIENT_MAX_PASSWORD_LEN
| #define MQTT_CLIENT_MAX_PASSWORD_LEN 16 | 
Definition at line 103 of file mqtt_client.h.
◆ MQTT_CLIENT_MAX_URI_LEN
| #define MQTT_CLIENT_MAX_URI_LEN 16 | 
Definition at line 82 of file mqtt_client.h.
◆ MQTT_CLIENT_MAX_USERNAME_LEN
| #define MQTT_CLIENT_MAX_USERNAME_LEN 16 | 
Definition at line 96 of file mqtt_client.h.
◆ MQTT_CLIENT_MAX_WILL_PAYLOAD_LEN
| #define MQTT_CLIENT_MAX_WILL_PAYLOAD_LEN 16 | 
Definition at line 117 of file mqtt_client.h.
◆ MQTT_CLIENT_MAX_WILL_TOPIC_LEN
| #define MQTT_CLIENT_MAX_WILL_TOPIC_LEN 16 | 
Definition at line 110 of file mqtt_client.h.
◆ MQTT_CLIENT_PRIVATE_CONTEXT
| #define MQTT_CLIENT_PRIVATE_CONTEXT | 
Definition at line 131 of file mqtt_client.h.
◆ MQTT_CLIENT_SUPPORT
| #define MQTT_CLIENT_SUPPORT ENABLED | 
Definition at line 40 of file mqtt_client.h.
◆ MQTT_CLIENT_TLS_SUPPORT
| #define MQTT_CLIENT_TLS_SUPPORT DISABLED | 
Definition at line 47 of file mqtt_client.h.
◆ MQTT_CLIENT_WS_SUPPORT
| #define MQTT_CLIENT_WS_SUPPORT DISABLED | 
Definition at line 54 of file mqtt_client.h.
◆ MqttClientContext
| #define MqttClientContext struct _MqttClientContext | 
Definition at line 147 of file mqtt_client.h.
Typedef Documentation
◆ MqttClientConnAckCallback
| typedef void(* MqttClientConnAckCallback) (MqttClientContext *context, uint8_t connectAckFlags, uint8_t connectReturnCode) | 
CONNACK message received callback.
Definition at line 178 of file mqtt_client.h.
◆ MqttClientPingRespCallback
| typedef void(* MqttClientPingRespCallback) (MqttClientContext *context) | 
PINGRESP message received callback.
Definition at line 243 of file mqtt_client.h.
◆ MqttClientPubAckCallback
| typedef void(* MqttClientPubAckCallback) (MqttClientContext *context, uint16_t packetId) | 
PUBACK message received callback.
Definition at line 195 of file mqtt_client.h.
◆ MqttClientPubCompCallback
| typedef void(* MqttClientPubCompCallback) (MqttClientContext *context, uint16_t packetId) | 
PUBCOMP message received callback.
Definition at line 219 of file mqtt_client.h.
◆ MqttClientPublishCallback
| typedef void(* MqttClientPublishCallback) (MqttClientContext *context, const char_t *topic, const uint8_t *message, size_t length, bool_t dup, MqttQosLevel qos, bool_t retain, uint16_t packetId) | 
PUBLISH message received callback.
Definition at line 186 of file mqtt_client.h.
◆ MqttClientPubRecCallback
| typedef void(* MqttClientPubRecCallback) (MqttClientContext *context, uint16_t packetId) | 
PUBREC message received callback.
Definition at line 203 of file mqtt_client.h.
◆ MqttClientPubRelCallback
| typedef void(* MqttClientPubRelCallback) (MqttClientContext *context, uint16_t packetId) | 
PUBREL message received callback.
Definition at line 211 of file mqtt_client.h.
◆ MqttClientSubAckCallback
| typedef void(* MqttClientSubAckCallback) (MqttClientContext *context, uint16_t packetId) | 
SUBACK message received callback.
Definition at line 227 of file mqtt_client.h.
◆ MqttClientTlsInitCallback
| typedef error_t(* MqttClientTlsInitCallback) (MqttClientContext *context, TlsContext *tlsContext) | 
TLS initialization callback.
Definition at line 253 of file mqtt_client.h.
◆ MqttClientUnsubAckCallback
| typedef void(* MqttClientUnsubAckCallback) (MqttClientContext *context, uint16_t packetId) | 
UNSUBACK message received callback.
Definition at line 235 of file mqtt_client.h.
Enumeration Type Documentation
◆ MqttClientState
| enum MqttClientState | 
MQTT client states.
Definition at line 159 of file mqtt_client.h.
Function Documentation
◆ mqttClientBindToInterface()
| error_t mqttClientBindToInterface | ( | MqttClientContext * | context, | 
| NetInterface * | interface | ||
| ) | 
Bind the MQTT client to a particular network interface.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] interface Network interface to be used 
- Returns
- Error code
Definition at line 445 of file mqtt_client.c.
◆ mqttClientClose()
| error_t mqttClientClose | ( | MqttClientContext * | context | ) | 
Close the connection with the MQTT server.
- Parameters
- 
  [in] context Pointer to the MQTT client context 
- Returns
- Error code
Definition at line 1266 of file mqtt_client.c.
◆ mqttClientConnect()
| error_t mqttClientConnect | ( | MqttClientContext * | context, | 
| const IpAddr * | serverIpAddr, | ||
| uint16_t | serverPort, | ||
| bool_t | cleanSession | ||
| ) | 
Establish connection with the MQTT server.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] serverIpAddr IP address of the MQTT server to connect to [in] serverPort TCP port number that will be used to establish the connection [in] cleanSession If this flag is set, then the client and server must discard any previous session and start a new one 
- Returns
- Error code
Definition at line 471 of file mqtt_client.c.
◆ mqttClientDeinit()
| void mqttClientDeinit | ( | MqttClientContext * | context | ) | 
Release MQTT client context.
- Parameters
- 
  [in] context Pointer to the MQTT client context 
Definition at line 1287 of file mqtt_client.c.
◆ mqttClientDisconnect()
| error_t mqttClientDisconnect | ( | MqttClientContext * | context | ) | 
Gracefully disconnect from the MQTT server.
- Parameters
- 
  [in] context Pointer to the MQTT client context 
- Returns
- Error code
Definition at line 1163 of file mqtt_client.c.
◆ mqttClientInit()
| error_t mqttClientInit | ( | MqttClientContext * | context | ) | 
Initialize MQTT client context.
- Parameters
- 
  [in] context Pointer to the MQTT client context 
- Returns
- Error code
Definition at line 52 of file mqtt_client.c.
◆ mqttClientInitCallbacks()
| void mqttClientInitCallbacks | ( | MqttClientCallbacks * | callbacks | ) | 
Initialize callback structure.
- Parameters
- 
  [in] callbacks Pointer to a structure that contains callback functions 
Definition at line 102 of file mqtt_client.c.
◆ mqttClientPing()
| error_t mqttClientPing | ( | MqttClientContext * | context, | 
| systime_t * | rtt | ||
| ) | 
Send ping request.
- Parameters
- 
  [in] context Pointer to the MQTT client context [out] rtt Round-trip time (optional parameter) 
- Returns
- Error code
Definition at line 1020 of file mqtt_client.c.
◆ mqttClientProcessEvents()
| error_t mqttClientProcessEvents | ( | MqttClientContext * | context, | 
| systime_t | timeout | ||
| ) | 
Process MQTT client events.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] timeout Maximum time to wait before returning 
- Returns
- Error code
Definition at line 67 of file mqtt_client_misc.c.
◆ mqttClientPublish()
| error_t mqttClientPublish | ( | MqttClientContext * | context, | 
| const char_t * | topic, | ||
| const void * | message, | ||
| size_t | length, | ||
| MqttQosLevel | qos, | ||
| bool_t | retain, | ||
| uint16_t * | packetId | ||
| ) | 
Publish message.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] topic Topic name [in] message Message payload [in] length Length of the message payload [in] qos QoS level to be used when publishing the message [in] retain This flag specifies if the message is to be retained [out] packetId Packet identifier used to send the PUBLISH packet 
- Returns
- Error code
Definition at line 637 of file mqtt_client.c.
◆ mqttClientPublishEx()
| error_t mqttClientPublishEx | ( | MqttClientContext * | context, | 
| const char_t * | topic, | ||
| const void * | message, | ||
| size_t | length, | ||
| bool_t | dup, | ||
| MqttQosLevel | qos, | ||
| bool_t | retain, | ||
| uint16_t * | packetId | ||
| ) | 
Publish message.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] topic Topic name [in] message Message payload [in] length Length of the message payload [in] dup DUP flag [in] qos QoS level to be used when publishing the message [in] retain This flag specifies if the message is to be retained [out] packetId Packet identifier used to send the PUBLISH packet 
- Returns
- Error code
Definition at line 660 of file mqtt_client.c.
◆ mqttClientRegisterCallbacks()
| error_t mqttClientRegisterCallbacks | ( | MqttClientContext * | context, | 
| const MqttClientCallbacks * | callbacks | ||
| ) | 
Register MQTT client callbacks.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] callbacks Pointer to a structure that contains callback functions 
- Returns
- Error code
Definition at line 116 of file mqtt_client.c.
◆ mqttClientRegisterPublishCallback()
| error_t mqttClientRegisterPublishCallback | ( | MqttClientContext * | context, | 
| MqttClientPublishCallback | callback | ||
| ) | 
Register publish callback function.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] callback Callback function to be called when a PUBLISH message is received 
- Returns
- Error code
Definition at line 209 of file mqtt_client.c.
◆ mqttClientRegisterTlsInitCallback()
| error_t mqttClientRegisterTlsInitCallback | ( | MqttClientContext * | context, | 
| MqttClientTlsInitCallback | callback | ||
| ) | 
Register TLS initialization callback function.
- Parameters
- 
  [in] context Pointer to the MQTT- client context [in] callback TLS initialization callback function 
- Returns
- Error code
Definition at line 184 of file mqtt_client.c.
◆ mqttClientSetAuthInfo()
| error_t mqttClientSetAuthInfo | ( | MqttClientContext * | context, | 
| const char_t * | username, | ||
| const char_t * | password | ||
| ) | 
Set authentication information.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] username NULL-terminated string containing the user name to be used [in] password NULL-terminated string containing the password to be used 
- Returns
- Error code
Definition at line 356 of file mqtt_client.c.
◆ mqttClientSetHost()
| error_t mqttClientSetHost | ( | MqttClientContext * | context, | 
| const char_t * | host | ||
| ) | 
Set the domain name of the server (for virtual hosting)
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] host NULL-terminated string containing the hostname 
- Returns
- Error code
Definition at line 275 of file mqtt_client.c.
◆ mqttClientSetIdentifier()
| error_t mqttClientSetIdentifier | ( | MqttClientContext * | context, | 
| const char_t * | clientId | ||
| ) | 
Set client identifier.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] clientId NULL-terminated string containing the client identifier 
- Returns
- Error code
Definition at line 329 of file mqtt_client.c.
◆ mqttClientSetKeepAlive()
| error_t mqttClientSetKeepAlive | ( | MqttClientContext * | context, | 
| uint16_t | keepAlive | ||
| ) | 
Set keep-alive value.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] keepAlive Maximum time interval that is permitted to elapse between the point at which the client finishes transmitting one control packet and the point it starts sending the next 
- Returns
- Error code
Definition at line 254 of file mqtt_client.c.
◆ mqttClientSetPacketId()
| error_t mqttClientSetPacketId | ( | MqttClientContext * | context, | 
| uint16_t | packetId | ||
| ) | 
Set packet identifier.
- Parameters
- 
  [in] context Pointer to the MQTT client context [out] packetId Packet identifier to be used 
- Returns
- Error code
Definition at line 604 of file mqtt_client.c.
◆ mqttClientSetTimeout()
| error_t mqttClientSetTimeout | ( | MqttClientContext * | context, | 
| systime_t | timeout | ||
| ) | 
Set communication timeout.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] timeout Timeout value, in seconds 
- Returns
- Error code
Definition at line 231 of file mqtt_client.c.
◆ mqttClientSetTransportProtocol()
| error_t mqttClientSetTransportProtocol | ( | MqttClientContext * | context, | 
| MqttTransportProtocol | transportProtocol | ||
| ) | 
Set the transport protocol to be used.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] transportProtocol Transport protocol to be used (TCP, TLS, WebSocket, or secure WebSocket) 
- Returns
- Error code
Definition at line 160 of file mqtt_client.c.
◆ mqttClientSetUri()
| error_t mqttClientSetUri | ( | MqttClientContext * | context, | 
| const char_t * | uri | ||
| ) | 
Set the name of the resource being requested.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] uri NULL-terminated string that contains the resource name 
- Returns
- Error code
Definition at line 302 of file mqtt_client.c.
◆ mqttClientSetVersion()
| error_t mqttClientSetVersion | ( | MqttClientContext * | context, | 
| MqttVersion | version | ||
| ) | 
Set the MQTT protocol version to be used.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] version MQTT protocol version (3.1 or 3.1.1) 
- Returns
- Error code
Definition at line 138 of file mqtt_client.c.
◆ mqttClientSetWillMessage()
| error_t mqttClientSetWillMessage | ( | MqttClientContext * | context, | 
| const char_t * | topic, | ||
| const void * | message, | ||
| size_t | length, | ||
| MqttQosLevel | qos, | ||
| bool_t | retain | ||
| ) | 
Specify the Will message.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] topic Will topic name [in] message Will message [in] length Length of the Will message [in] qos QoS level to be used when publishing the Will message [in] retain This flag specifies if the Will message is to be retained 
- Returns
- Error code
Definition at line 392 of file mqtt_client.c.
◆ mqttClientSubscribe()
| error_t mqttClientSubscribe | ( | MqttClientContext * | context, | 
| const char_t * | topic, | ||
| MqttQosLevel | qos, | ||
| uint16_t * | packetId | ||
| ) | 
Subscribe to topic.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] topic Topic filter [in] qos Maximum QoS level at which the server can send application messages to the client [out] packetId Packet identifier used to send the SUBSCRIBE packet 
- Returns
- Error code
Definition at line 791 of file mqtt_client.c.
◆ mqttClientTask()
| error_t mqttClientTask | ( | MqttClientContext * | context, | 
| systime_t | timeout | ||
| ) | 
Process MQTT client events.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] timeout Maximum time to wait before returning 
- Returns
- Error code
Definition at line 1134 of file mqtt_client.c.
◆ mqttClientUnsubscribe()
| error_t mqttClientUnsubscribe | ( | MqttClientContext * | context, | 
| const char_t * | topic, | ||
| uint16_t * | packetId | ||
| ) | 
Unsubscribe from topic.
- Parameters
- 
  [in] context Pointer to the MQTT client context [in] topic Topic filter [out] packetId Packet identifier used to send the UNSUBSCRIBE packet 
- Returns
- Error code
Definition at line 906 of file mqtt_client.c.
