Lewis Van Winkle - Hands-On Network Programming with C: Learn socket programming in C and write secure and optimized network code

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First published: May 2019

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ISBN 978-1-78934-986-3

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Lewis Van Winkle is a software programming consultant, entrepreneur, and founder of a successful IoT company. He has over 20 years of programming experience after publishing his first successful software product at the age of 12. He has over 15 years of programming experience with the C programming language on a variety of operating systems and platforms. He is active in the open source community and has published several popular open source programs and librariesmany of them in C. Today, Lewis spends much of his time consulting, where he loves taking on difficult projects that other programmers have given up on. He specializes in network systems, financial systems, machine learning, and interoperation between different programming languages.

Daniele Lacamera is a software technologist and researcher with vast experience in software design and development on embedded systems for different industries. He is currently working as freelance software developer and trainer. He is a worldwide expert in TCP/IP and transport protocol design and optimization, with more than 20 academic publications on the topic. He supports free software by contributing to several projects, including the Linux kernel, and is involved within a number of communities and organizations that promote the use of free and open source software in the IoT.

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Packt first contacted me about writing this book nearly a year ago. It's been a long journey, harder than I anticipated at times, and I've learned a lot. The book you hold now is the culmination of many long days, and I'm proud to finally present it.

I think C is a beautiful programming language. No other language in everyday use gets you as close to the machine as C does. I've used C to program 8-bit microcontrollers with only 16 bytes of RAM, just the same as I've used it to program modern desktops with multi-core, multi-GHz processors. It's truly remarkable that C works efficiently in both contexts.

Network programming is a fun topic, but it's also a very deep one; a lot is going on at many levels. Some programming languages hide these abstractions. In the Python programming language, for example, you can download an entire web page using only one line of code. This isn't the case in C! In C, if you want to download a web page, you have to know how everything works. You need to know sockets, you need to know Transfer Control Protocol (TCP), and you need to know HTTP. In C network programming, nothing is hidden.

C is a great language to learn network programming in. This is not only because we get to see all the details, but also because the popular operating systems all use kernels written in C. No other language gives you the same first-class access as C does. In C, everything is under your control you can lay out your data structures exactly how you want, manage memory precisely as you please, and even shoot yourself in the foot just the way you want.

When I first began writing this book, I surveyed other resources related to learning network programming with C. I found much misinformation not only on the web, but even in print. There is a lot of C networking code that is done wrong. Internet tutorials about C sockets often use deprecated functions and ignore memory safety completely. When it comes to network programming, you can't take the