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

Installing OpenSSL

The OpenSSL library can be tricky to get going on Windows.

If you are brave, you can obtain the OpenSSL library source code directly from You will, of course, need to build OpenSSL before it can be used. Building OpenSSL is not easy, but instructions are provided in the INSTALL and NOTES.WIN files included with the OpenSSL source code.

An easier alternative is to install prebuilt OpenSSL binaries. You can find a list of prebuilt OpenSSL binaries from the OpenSSL wiki at You will need to locate binaries that match your operating system and compiler. Installing them will be a matter of copying the relevant files to the MinGW include, lib, and bin directories.

The following screenshot shows a binary OpenSSL distribution. The include and lib folders should be copied over to c:\mingw\ and merged with the existing folders, while openssl.exe and the two DLL files need to be placed in c:\mingw\bin\:

You can try building openssl_version.c from Chapter 9, Loading Secure Web Pages with HTTPS and OpenSSL, to test that everything is installed correctly. It should look like the following: