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 ...

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 ...

If you're writing a Bash script, you will invariably need to pass values to it—aka arguments or positional parameters. Bash's approach is a little clunky, but it works. Examples are the easiest way to ...

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 ...

The eval command allows you to run the contents of variables as commands and can be very useful, especially in scripts. There are probably a lot of Linux users who have never encountered the eval ...

Typically we interact with the Linux operating system through what is referred to as a shell interpreter. A common interpreter is the Bourne Again Shell, which people call by the catchy name of bash ...

Want to know the tricks of replacing a variable in a file using the SED command? This article will give you an overview of replacing a variable value in a file using SED. Before replacing a variable ...