Book Image

Hands-On Network Programming with C

By : Lewis Van Winkle
Book Image

Hands-On Network Programming with C

By: Lewis Van Winkle

Overview of this book

Network programming enables processes to communicate with each other over a computer network, but it is a complex task that requires programming with multiple libraries and protocols. With its support for third-party libraries and structured documentation, C is an ideal language to write network programs. Complete with step-by-step explanations of essential concepts and practical examples, this C network programming book begins with the fundamentals of Internet Protocol, TCP, and UDP. You’ll explore client-server and peer-to-peer models for information sharing and connectivity with remote computers. The book will also cover HTTP and HTTPS for communicating between your browser and website, and delve into hostname resolution with DNS, which is crucial to the functioning of the modern web. As you advance, you’ll gain insights into asynchronous socket programming and streams, and explore debugging and error handling. Finally, you’ll study network monitoring and implement security best practices. By the end of this book, you’ll have experience of working with client-server applications and be able to implement new network programs in C. The code in this book is compatible with the older C99 version as well as the latest C18 and C++17 standards. You’ll work with robust, reliable, and secure code that is portable across operating systems, including Winsock sockets for Windows and POSIX sockets for Linux and macOS.
Table of Contents (26 chapters)
Title Page
About Packt


In this chapter, we learned about the basics of using sockets for network programming. Although there are many differences between Berkeley sockets (used on Unix-like operating systems) and Winsock sockets (used on Windows), we mitigated those differences with preprocessor statements. In this way, it was possible to write one program that compiles cleanly on Windows, Linux, and macOS.

We covered how the UDP protocol is connectionless and what that means. We learned that TCP, being a connection-oriented protocol, gives some reliability guarantees, such as automatically detecting and resending lost packets. We also saw that UDP is often used for simple protocols (for example, DNS) and for real-time streaming applications. TCP is used for most other protocols.

After that, we worked through a real example by converting a console application into a web server. We learned how to write the program using the getaddrinfo() function, and why that matters for making the program IPv4/IPv6-agnostic...