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 libssh

You can try installing libssh from your package manager with the following command:

sudo apt-get install libssh-dev

The problem is that the code in this book is not compatible with older versions of libssh. Therefore, I recommend you build libssh yourself.

You can obtain the latest libssh library from If you are proficient in installing C libraries, feel free to give it a go. Otherwise, read on for the step-by-step instructions.

Before beginning, be sure that you've first installed the OpenSSL libraries successfully. These are required by the libssh library.

We will also need CMake installed in order to build libssh. You can obtain CMake from You can also get it from your distro's packaging tool with the following command:

sudo apt-get install cmake

Finally, the zlib library is also required by libssh. You can install the zlib library using this command:

sudo apt-get install zlib1g-dev

Once you have CMake, the zlib library, and the OpenSSL library installed, locate the version of libssh you would like from Version 0.8.7 is the latest at the time of writing. You can download and extract the libssh source code with the following commands:

 tar xvf libssh-0.8.7.tar.xz
 cd libssh-0.8.7

I recommend that you take a look at the installation instructions included with libssh. You can use less to view them. Press the Q key to quit less:


Once you've familiarized yourself with the build instructions, you can try building libssh with these commands:

mkdir build
cd build
cmake ..

The final step is to install the library with the following command:

sudo make install