Mastering Linux Shell Scripting: A practical guide to Linux command-line, Bash scripting, and Shell programming, 2nd Edition

Book Synopsis: Master the complexities of Bash shell scripting and unlock the power of shell for your enterpriseKey FeaturesIdentify high-level steps such as verifying user inputUse the command line and conditional statements for creating and executing simple shell scriptsCreate and edit dynamic shell scripts to manage complex and repetitive tasksBook DescriptionMastering shell scripting is made easy with this book that guides you through everything, right from using the Linux command line through to creating Bash scripts, while also helping you make informed choices about the elements you employ.You can use your favorite editor and start writing Bash scripts in a step-by-step manner. The book will also help you get to grips with the fundamentals of creating and running a script in normal mode, as well as in debug mode. You'll explore code snippets from various conditional statements, and realize the power of repetition and loops in your shell script. You will gradually learn to write complex shell scripts, before delving into file system administration, directories, and system administration such as networking, process management, user authentication, package installation, and regular expressions. Toward the concluding chapters, you will learn how to use Python as an alternative for Bash scripting.By the end of this book, you will be well-versed with shell scripts and have mastered the technique of automating and communicating with your system through keyboard expressions.What you will learnDevelop, execute, and debug your first Bash scriptCreate interactive scripts that prompt for user inputBuild menu structures for operators with little command-line experienceDevelop scripts that dynamically edit web configuration files to produce a new virtual hostWrite scripts that use AWK to search log files and generate reportsDraft effective scripts using functions as building blocks, reducing maintenance and build timeCompare different script languages such as Python with BashUse the command line to bypass the graphical user interface (GUI) and automate common tasksWho This Book Is ForIf you are a Linux administrator or a system administrator and are interested in automating daily tasks to save time and effort, then this book is for you. Basic shell scripting and command-line experience will be required. Familiarity with the tasks you need to automate will also be helpful.Table of ContentsWhat and Why of Scripting with BASHCreating Interactive ScriptsConditions attachedCreating Code SnippetsAlternative syntaxIterating with LoopsCreating Building Blocks with FunctionsIntroducing sedAutomating Apache Virtual HostsAWK FundamentalsRegular expressionsSummarizing Logs with awkA Better lastlog with AwkUsing Python as a BASH Scripting Alternative Read more