Mastering Unix Shell Scripting

Learn to create shell scripts to solve real-world UNIX problems

Get ready to take on the UNIX world! UNIX expert Randal K. Michael guides you through every detail of writing shell scripts to automate specific tasks. Each chapter begins with a typical, everyday UNIX challenge, and then shows you how to take basic syntax and turn it into a shell scripting solution. Throughout the book, you’ll also find complete shell scripts plus detailed descriptions of each part. You’ll be able to modify this information to build tools that monitor for specific system events and situations, building the skills to solve real-world system administration problems.

• Make the most of Bash, Bourne, and Korn shells
• Execute the proper commands for each UNIX flavor
• Define the correct command syntax to meet a specific shell scripting goal
• Filter the commands’ output to strip out unneeded data
• Build options into the shell script to give the end user more flexibility on the command line
• Replicate data using rsync
• Create snapshot-style backups using Dirvish
• Work with records files to parse data
• Prepare for government audits using specific commands

Contents

Part I: The Basics of Shell Scripting

Chapter 1: Scripting Quick Start and Review

Chapter 2: 24 Ways to Process a File Line-by- Line

Chapter 3: Automated Event Notification

Chapter 4: Progress Indicators Using a Series of Dots, a Rotating Line, or Elapsed Time

Part II: Scripts for Programmers, Testers, and Analysts

Chapter 5: Working with Record Files

Chapter 6: Automated FTP Stuff

Chapter 7: Using rsync to Efficiently Replicate Data

Chapter 8: Automating Interact ive Programs with Expect and Autoexpect

Chapter 9: Finding Large Files and Files of a Specific Type

Chapter 10: Process Monitoring and Enabling Pre-Processing, Startup, and Post-Processing Events

Chapter 11: Pseudo -Random Number and Data Generation

Chapter 12: Creating Pseudo -Random Passwords

Chapter 13: Floating-Point Math and the be Utility

Chapter 14: Number Base Conversions

Chapter 15: hgrep: Highlighted grep Script

Chapter 16: Monitoring Processes and Applications

Part Ill: Scripts for Systems Administrators

Chapter 17: Filesystem Monitoring

Chapter 18: Monitoring Paging and Swap Space

Chapter 19: Monitoring System Load

Chapter 20: Monitoring for Stale Disk Partitions (AIX-Specific)

Chapter 21: Turning On/ Off SSA Identification Lights

Chapter 22: Automated Hosts Pinging with Notification of Failure

Chapter 23: Creating a System-Configuration Snapshot

Chapter 24: Compiling, Installing, Configuring, and Using sudo

Chapter 25: Print-Queue Hell: Keeping the Printers Printing

Chapter 26: Those Pesky Sarbanes-Oxley (SOX) Audits

Chapter 27: Using Dirvish with rsync to Create Snapshot-Type Backups

Chapter 28: Monitoring and Auditing User Keystrokes

About the Author

Randal K. Michael is a UNIX Systems Administrator working as a contract consultant. He teaches UNIX shell scripting in corporate settings, where he writes shell scripts to address a variety of problems and tasks ranging from monitoring systems to replicating large databases. He has more than 30 years of experience in the industry and 15 years of experience as a UNIX Systems Administrator, working on AIX, HP-UX, Linux, OpenBSD, and Solaris.