Book Image

Linux Command Line and Shell Scripting Techniques

By : Vedran Dakic, Jasmin Redzepagic
Book Image

Linux Command Line and Shell Scripting Techniques

By: Vedran Dakic, Jasmin Redzepagic

Overview of this book

Linux Command Line and Shell Scripting Techniques begins by taking you through the basics of the shell and command-line utilities. You’ll start by exploring shell commands for file, directory, service, package, and process management. Next, you’ll learn about networking - network, firewall and DNS client configuration, ssh, scp, rsync, and vsftpd, as well as some network troubleshooting tools. You’ll also focus on using the command line to find and manipulate text content, via commands such as cut, egrep, and sed. As you progress, you'll learn how to use shell scripting. You’ll understand the basics - input and output, along with various programming concepts such as loops, variables, arguments, functions, and arrays. Later, you’ll learn about shell script interaction and troubleshooting, before covering a wide range of examples of complete shell scripts, varying from network and firewall configuration, through to backup and concepts for creating live environments. This includes examples of performing scripted virtual machine installation and administration, LAMP (Linux, Apache, MySQL, PHP) stack provisioning and bulk user creation for testing environments. By the end of this Linux book, you’ll have gained the knowledge and confidence you need to use shell and command-line scripts.
Table of Contents (19 chapters)

Converting DOS text to Linux text and vice versa

This is a strange idea – you might have thought a .txt file is a .txt file, right? Wrong.

There are subtle differences between .txt file formats in DOS/Windows and Linux. Sometimes, those differences can make you mad in a matter of seconds. We've had our fair share of experiences of that – scripts not working as input files were prepared on Windows, not on Linux; different treatment of CSV files in Excel by design... sometimes it's just too funny when, after hours of deliberation, you realize that something as simple as a .txt file created on another OS can make such a mess. Let's explain what the problem is and work through it.

Getting ready

We just need one Ubuntu machine for this recipe. Let's say we are going to continue using cli1 to master these commands. Furthermore, we need to install one package, called dos2unix. So, if we are using cli1 (Ubuntu), we need to type in the following command...