Variables often look like $var, but they also look like $1, $*, $? and $$. Let's take a look at what all these $ values can tell you. A lot of important values are ...

Do you want to create a Shell script in your Linux system? This guide will take you through how to create a shell script using multiple text editors, how to add comments, and how to use Shell ...

This post follows up on Part 1 by examining the many ways that you can test the value of variables – e.g., whether they equal particular strings like “yes” or “no”, if they have a numeric value, if ...

There I was, trying to come up with a topic for this column, when I did what I usually do when stumped: I sent a question out to my Twitter followers. This time, I got a great answer, from John ...

Linux 101: What are environment variables? Your email has been sent Jack Wallen introduces you to Linux environment variables. What are they and how are they set and ...

In our first tutorial on command line wizardry, we covered simple redirection and the basics of sed, awk, and grep. Today, we’re going to introduce the concepts of simple variable substitution and ...

The printf command offers well-defined behavior following the POSIX standard, which means it works the same way across shells and systems. Where echo often fails with escape sequences, printf handles ...

Attaching a remote drive or directory on a Windows box is called “drive mapping” though the process is essentially the same as what we call mounting in the Unix world. While I rarely spend any ...

If you are a traditional programmer, using bash for scripting may seem limiting sometimes, but for certain tasks, bash can be very productive. It turns out, some of the limits of bash are really ...