AIX Shell Programming

Prerequisites:

The course assumes knowledge of the AIX Operating System to the level covered in the AIX Basics Course. Some programming experience may also prove advantageous.

Course Description:

This course is designed to give delegates practical experience in developing and writing AIX shell scripts.Most of the built-in shell commands are introduced together with the main program control structures.This course is not suitable for C shell programmers.

The delegates will practise:

• Writing simple scripts to enhance basic command output
• Using the various shell quoting mechanisms appropriately
• Manipulating shell variables and user-defined variables in scripts
• Implementing conditional execution facilities
• Using the shell's built-in loop constructs where appropriate
• Writing scripts to trap user interrupts
• Developing menu-driven shell scripts

This course includes the following modules:

AIX Command Review

• Basic Unix commands
• General commands
• File and directory handling commands
• Filename generation characters
• I/O Redirection features
• Other commands

Getting Started

• What is a shell script?
• Development guidelines
• Creating and editing shell scripts
• Naming and storing shell scripts
• Executing shell scripts

Using Variables

• Environment variables
• Local variables
• Assigning values to variables
• Assessing variable values
• Using quotes
• Delimiting variable names
• Echo control sequences

Integer Arithmetic

• Using the expr command
• Using the (( )) notation

Handling Run Time Data

• The read command
• Command line arguments

Condition Execution

• The if statement
• The test command
• Other test notations
• Default and substitute variables
• Exit status codes

Loop Constructs

• The while loop
• The until loop
• The for loop
• The while true and until false loops
• Loop control commands

Multi-branch Decisions

• The case statement
• Menu driven applications

Functions

• What is a function?
• Syntax
• Examples

Interrupt Handling

• Interrupt signals
• Trapping interrupts

Additional Features and Facilities

• The exec commands
• The includes notation
• More about loops
• Arrays
• Here Documents