Jack Wallen introduces you to Linux environment variables. What are they and how are they set and unset? How many times have you installed something on Linux, only to find out that you need to set ...

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 ...

If you're working in a Linux environment, chances are you've encountered environment variables—even if you didn’t realize it at the time. They quietly power much of what goes on behind the scenes in ...

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 ...

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 ...

Bash vs. Fish? I've tried both Linux shells, and one makes using the command line much easier ...

I'm working on some scripts that execute on various servers, and I'm trying to consolidate them into one. The problem is that I need to run remote commands but can't ...

Linux offers a couple of easy ways to record commands you type so that you can review or rerun them. Recording the commands that you run on the Linux command line can be useful for two important ...