Vivek Nagarajan 
Command Line Fundamentals [EPUB ebook] 
Learn to use the Unix command-line tools and Bash shell scripting

The most basic interface to a computer—the command line—remains the most flexible and powerful way of processing data and performing and automating various day-to-day tasks.
Command Line Fundamentals begins by exploring the basics, and then focuses on the most common tool, the Bash shell (which is standard on all Linux and i OS systems). As you make your way through the book, you’ll explore the traditional Unix command-line programs as implemented by the GNU project. You’ll also learn to use redirection and pipelines to assemble these programs to solve complex problems.
By the end of this book, you’ll have explored the basics of shell scripting, allowing you to easily and quickly automate tasks.