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 ...

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 ...

Variable names are alphanumeric but must start with a letter. The length of a variable name is limited to thirty-two characters for non-SAS data set variables Model variables are declared by VAR, ...

Ever wondered why programming in Bash is so difficult? Bash employs the same constructs as traditional programming languages; however, under the hood, the logic is rather different. The Bourne-Again ...

The shell does far more than run commands. Here’s how Bash expands your input behind the scenes so you can write cleaner, more reliable commands.