Welcome back! In the previous lesson, we explored the essentials of concurrency and multithreading. By now, you should have a basic understanding of what concurrency is and how it can help improve the performance and resource utilization of your programs. You've even had a taste of creating a simple thread in C++. Today, we'll delve into the lifecycle of a thread and the basic operations you can perform with threads. Understanding these concepts is crucial for managing threads effectively in your applications.

In this unit, we'll cover the fundamental aspects of the thread lifecycle and operations in C++. Here's what you can expect to learn:

1. Creating Threads with Function Objects and Lambdas:
   • We'll explore different ways to create threads in C++. Whether it's using function objects and lambdas, knowing these methods will give you flexibility in defining thread tasks.
2. Thread Methods:
   • We'll look into various operations you can perform on threads, such as join(), detach(), and thread identification. These methods help in managing the execution of threads and ensuring that your program runs smoothly.

Now, let's take a closer look at each of these topics and see how they work in practice.

Let's start by defining a runnable class that can be used by threads to execute tasks:

In this code snippet, we have a class RunnableDemo that defines a callable object. The class has a constructor that takes a std::string argument and an overloaded operator() method that prints a message indicating the thread is running. The operator() method allows objects of this class to be called like a function, making them suitable for use with threads.

Why not use a regular function instead of a class? Using a class allows us to encapsulate data and behavior related to the thread, making it more modular and reusable. The operator() method acts as the entry point for the thread's execution.

Understanding the lifecycle and basic operations of threads is essential for writing robust and efficient multi-threaded programs. Here's why these concepts are important:

• Flexibility in Thread Creation: Being adept at creating threads using different methods gives you the flexibility to choose the best approach for your specific use case.
• Operations and Synchronization: Mastering thread methods such as join() and detach() is crucial for synchronization, preventing issues like deadlocks and ensuring that threads execute as intended.