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 worked through implementing an HTTP server in C from scratch. That's no small feat! Although the text-based nature of HTTP makes parsing HTTP requests simple, we needed to spend a lot of effort to ensure that multiple clients could be served simultaneously. We accomplished this by buffering received data for each client separately. Each client's state information was organized into a linked list.

Another difficulty was ensuring the safe handling of received data and detecting errors. We learned that a programmer must be very careful when handling network data to avoid creating security risks. We also saw that even very subtle issues, such as Windows's special filenames, can potentially create dangerous security holes for networked server applications.

In the next chapter, Chapter 8Making Your Program Send Email, we move on from HTTP and consider the primary protocol associated with email—Simple Mail Transfer Protocol (SMTP).