shell variables

In this post we learn to manage environment variables in the shell. These variables are often needed by applications. $ dollar sign Another important character interpreted by the shell is the dollar sign $. The shell will look for an environment variable named like the string following the dollar sign and replace it with the … Read more

control operators

In this post we put more than one command on the command line using control operators. We also briefly discuss related parameters ($?) and similar special characters(&). ; semicolon You can put two or more commands on the same line separated by a semicolon ; . The shell will scan the line until it reaches … Read more

working with linux directories

This module is a brief overview of the most common commands to work with directories: pwd, cd, ls, mkdir and rmdir. These commands are available on any Linux (or Unix) system. pwd The you are here sign can be displayed with the pwd command (Print Working Directory). Go ahead, try it: Open a command line … Read more