Boost C++ Libraries

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Chapter 1. Boost.MQTT5: a C++17 MQTT client

Chapter 1. Boost.MQTT5: a C++17 MQTT client

Ivica Siladić

Bruno Iljazović

Korina Šimičević

Copyright © 2023-2025 Mireo

Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

Table of Contents

Introduction

Getting Started

Choosing a Suitable Transport Protocol
Configuring Your MQTT Connection
Establishing a Connection
Using the Client
Debugging the Client

Built-in Auto-Reconnect and Retry Mechanism


Considerations and Limitations

Maintaining a Stable Connection

Understanding Keep Alive and Server Keep Alive
Detecting and Handling Half-open Connections

Optimising Communication

The Multiflight Mode
Efficient Bandwidth Usage With Packet Queuing
Packet Ordering

Disconnecting the Client

Restarting the Client After Disconnection

Compliance With Boost.Asio

Allocators
Per-Operation Cancellation
Executors

Using the mqtt_client in a Multithreaded Environment

Thread Safety of ASIO-Compliant Objects
Executors, Threads, and Strands
Writing Thread-Safe Code