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 ...

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 ...

protect a variable name from surrounding characters. $ export foo=foo $ echo ${foo}bar # foo exists so this works as expected foobar $ echo $foobar # foobar doesn't ...

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 ...

Jack Wallen shows you how to pass environment variables to Docker containers for a more efficient development process. Did you know you can pass environment variables from your host to Docker ...

The "path" environment variable in Linux specifies the directories the terminal looks in when you type the path to a command. For example, when you type "command," Linux looks through each directory ...