Using the Linux Command Line

Glenn Norman

This is post 1 of 11 in the series “The Linux Command Line” Objectives Understanding Linux file systems, users and groups, and permissions. Becoming familiar with basic navigational commands, built-in and binary executables, and advanced functions available at the bash command line. Learning how to use special permissions on executables and directories to manage availability …

Flow Control

Tux

This is post 12 of 19 in the series “[ Shell Scripting ]” The Bourne/bash shell supports a variety of conditionals, loops and other flow control operations. You’ll use these often. if The if statement is a simple conditional. Its syntax is: if condition ; then commands [elif condition ; then commands]… [else commands] fi …

Pipes

Glenn Norman

This is post 10 of 19 in the series “[ Shell Scripting ]” Any number of commands can be pipelined together. command1 | command2 The above command creates a pipe: the standard output of command1 is connected to the standard input of command2. Any command that can accept Standard Input and produce Standard Output is …

Shell Variables

Linux bash shell

This is post 8 of 19 in the series “[ Shell Scripting ]” In Unix there are three kinds of variables: System Variables (you normally can’t change these), Environment Variables (which are yours, and specific to your environment) and Shell Variables (which you declare and use in programming). Bourne, bash and Korn allow you to …

Debugging

Glenn Norman

This is post 6 of 19 in the series “[ Shell Scripting ]” There are several very elementary techniques you can use to debug your scripts. Switch Your Shell to Execute (Debug) Mode Remember the Order of Operations? You can change the mode of the Bourne/bash/Korn shell to show you what your command looks like …