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
Dedication
About Packt
Contributors
Preface
Index

TCP socket tips


The Transmission Control Protocol (TCP) is a fantastic protocol, and TCP sockets provide a beautiful abstraction. They present discrete packets on an unreliable network as a reliable, continuous stream of data. To the programmer, sending and receiving data from a peer anywhere in the world is made nearly as easy as reading and writing to a file.

TCP works very well to hide network shortcomings. When a flaky network drops a few packets, TCP faithfully sorts out the mess and retransmits as needed. The application using TCP receives the data in perfect order. The application doesn't even know there was a network problem, and it certainly doesn't need to address the problem.

With this abstraction, like all abstractions, comes some inherent risk. TCP tries very hard to make networks look reliable. It usually succeeds, but sometimes, abstractions leak. What happens if your network cable is cut? What happens if the application you are connected to crashes? TCP isn't magic. It can...