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 https://www.libssh.org/. 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 https://cmake.org/. 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...