Shell Scripting Workshop (GL375)

Module 1: Introduction to the Shell

• Shell Script Strengths and Weaknesses

• Shells • Switching User Contexts

• Example Shell Script

• Shell and Environment Variables

• Key Environment Variables

• Which and Type

• General Quoting Rules

• Nesting Commands

• Help from Commands and Documentation

• whereis

• Getting Help within the Graphical Desktop

• Getting Help with man & info

Lab Tasks

• Shell Variables

• Shell Meta-Characters

• Command Substitution

 

Module 2: Shell Scripting Basics

• Positional Parameters

• Input & Output

• printf

• alias

• Functions

• Colors in Scripts

• Custom Bash Prompts

Lab Tasks

• Aliases

• Bash Login Scripts

• Create “userinfo” and “sysinfo” functions

 

Module 3: Working with Files

• Communication Channels

• File Redirection

• Piping Commands Together

• Doing Math

• Filesystem Structures

• Determining Disk Usage with df and du

• cron

• The crontab Command

• crontab Format

• /etc/cron.*/ Directories

• Sending Email with mailx

Lab Tasks

• Disk and Filesystem Usage

• Redirection and Pipes

 

Module 4: Regular Expressions

• Searching Inside Files

• Regular Expression Overview

• Regular Expressions

• RE Character Classes

• Regex Quantifiers

• RE Parenthesis

• The Streaming Editor

Lab Tasks

• Pattern Matching with Regular Expressions

• Extended Regular Expressions

• Using Regular Expressions with sed

 

 

Module 5: Branching and Looping

• Exit Status

• Comparisons with test

• Conditional Statements

• Flow Control: case

• Flow Control: while and until Loops

• The borne for-Loop

• Flow Control: select

• Lab Tasks

• Reporting User Statistics

• Monitoring Filesystem Usage}

 

Module 6: Data Munging

• Text Processing with Awk

• Text Sorting

• Duplicate Removal Utility

• Extracting Columns of Text Lab Tasks

• Create “rmhost” function

• Create “showenv”function

• Parsing Mail Server Logs

• Fixing Incorrect Files

 

Module 7: Security, Whitespace, and Other Gotchas

• Gotcha: Quoting Variables

• Gotcha: Locales

• Gotchas: Maximum Command Length

• Gotcha: Whitespace in for Loops

• Reading Files with while

• Gotcha: $IFS

• Gotcha: Printing in .bashrc

• Gotcha: Aliases

Lab Tasks

• Renaming MP3 Files

• Split and Display $PATH

• A tar-based Backup

 

Appendix A: Challenge

• Apache Configuration Files

• httpd.conf – VirtualHost Configuration

Lab Tasks

• Automated Virtual Host Provisioning

 

Appendix B: Emacs

• Emacs

• The Emacs Interface

• Basic Emacs

• More Emacs Commands

Lab Tasks

• Text Editing with Emacs

 

Appendix C: The Secure Shell (SSH)

• OpenSSH Client & Server Configuration

• Accessing Remote Shells

• Transferring Files

• SSH Key Management 

Prerequisites

Solid understanding of Unix-based systems and proficiency on the Unix or Linux command line.