Book Image

Hands-On System Programming with C++

By : Dr. Rian Quinn
Book Image

Hands-On System Programming with C++

By: Dr. Rian Quinn

Overview of this book

C++ is a general-purpose programming language with a bias toward system programming as it provides ready access to hardware-level resources, efficient compilation, and a versatile approach to higher-level abstractions. This book will help you understand the benefits of system programming with C++17. You will gain a firm understanding of various C, C++, and POSIX standards, as well as their respective system types for both C++ and POSIX. After a brief refresher on C++, Resource Acquisition Is Initialization (RAII), and the new C++ Guideline Support Library (GSL), you will learn to program Linux and Unix systems along with process management. As you progress through the chapters, you will become acquainted with C++'s support for IO. You will then study various memory management methods, including a chapter on allocators and how they benefit system programming. You will also explore how to program file input and output and learn about POSIX sockets. This book will help you get to grips with safely setting up a UDP and TCP server/client. Finally, you will be guided through Unix time interfaces, multithreading, and error handling with C++ exceptions. By the end of this book, you will be comfortable with using C++ to program high-quality systems.
Table of Contents (16 chapters)

Comparing C++ versus mmap benchmark

In this example, we will benchmark the difference between reading the contents of a file using std::fstream and reading them using mmap().

It should be noted that the mmap() function leverages a system call to directly map a file into the program, and we expect mmap() to be faster than the C++ APIs highlighted in this chapter. This is because the C++ APIs have to perform an additional memory copy, which is obviously slower.

We will start this example by defining the size of the file we plan to read, as follows:

constexpr auto size = 0x1000;

Next, we must define a benchmark function to record how long it takes to perform an action:

template<typename FUNC>
auto benchmark(FUNC func) {
auto stime = std::chrono::high_resolution_clock::now();
auto etime = std::chrono::high_resolution_clock::now();

return etime - stime;