Here is a list of requirements for this book:

• Intermediate knowledge of C++.
• Any additional requirements are mentioned in the Technical requirements section of each chapter.
• Disclaimer: The C++20 standard has been approved (that is, technically finalized) by WG21 in a meeting in Prague at the end of February. This means that the GCC compiler version that this book uses, 8.3.0, does not include (or has very, very limited support for) the new and cool C++20 features. For this reason, the Docker image does not include the C++20 recipe code.
  GCC keeps the development of the newest features in branches (you have to use appropriate flags for that, for example, -std=c++2a); therefore, you are encouraged to experiment with them by yourself. So, clone and explore the GCC contracts and module branches and have fun.
• Some recipes (especially in Chapter 11, Scheduling) require the Docker image running with admin privileges to execute properly. Depending on your Docker configuration, you may be required to run the Docker with sudo. To avoid that you can create a Linux group (for example, docker) and add users to it.

You can download the example code files for this book from your account at www.packt.com. If you purchased this book elsewhere, you can visit www.packtpub.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packt.com.
2. Select the Support tab.
3. Click on Code Downloads.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/C-System-Programming-Cookbook. In case there's an update to the code, it will be updated on the existing GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: https://static.packt-cdn.com/downloads/9781838646554_ColorImages.pdf.

Please visit the following link to check out the CiA videos: http://bit.ly/2uXftdA

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "In the second step, we started developing the main method."

A block of code is set as follows:

 std::cout << "Start ... " << std::endl;
    {
        User* developer = new User();
        developer->cheers();
        delete developer;
    }

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

auto* mapPtr = static_cast<T*> (mmap(0, sizeof(T) * n, 
                                PROT_READ | PROT_WRITE, 

Any command-line input or output is written as follows:

 $ grep "text" filename
 $ ls -l | grep filename

Bold: Indicates a new term, an important word, or words that you see on screen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "Select System info from the Administration panel."