Bash Programming - 3 Days

Students learn to read, write, and debug shell scripts, thus increasing productivity by taking full advantage of the bash shell.

Audience: Linux or UNIX users, programmers, and system administrators.

Prerequisites: Fundamentals of UNIX or Fundamentals of Linux

UNIX Processes

What is a Process?
Process Structure
The ps Utility
Options to the ps Utility
Background Commands (&)
Killing Background Processes
Redirecting the Standard Error

Getting Started

What is a Shell?
Running Scripts
Specifying the Script's Interpreter
The PATH Environment Variable
Sub-shells

Variables

Shell Variables
The read Command
The export Command
The Shell Environment
Parameter Expansion
Command Substitution

The Login Process

The Login Process
The System Profile Script
Your .bash_profile Script
The . Command

Conditional Statements

The Exit Status of Commands
Command Line Examples
The test Command
The if-then-else Construct
The elif Construct
case Statements

Loops

The for Loop
The while Loop
break and continue
Reading Lines From Files
Using Arrays with Loops

Special Variables

$$ - PID of Shell
Command-Line Arguments
$# - Number of Arguments
$* - All Arguments
The shift Command
The set Command
Getting Options
Quoting Mechanisms
Single vs. Double Quotes
What is a Here Document?
Using a Here Document
Here Document Quoting
Ignoring Leading Tabs
Functions
Shell Functions
Passing Arguments to Functions
Returning Values from Functions
Function Declarations
Advanced Programming
Shell Arithmetic
The select Statement
Terminal Independence in Scripts
The eval Command
Debugging Techniques
Using echo
Using Standard Error
Script Tracing
Options for Debugging
Conditional Debugging