Korn Shell Programming

Course review:

Introduction

• UNIX Shells
• Comparing Shells

Scripting

• Shell script basics
• Comments
• Printing output
• Quoting
• Creating shell variables
• Predefined shell variables
• Environment variables
• Dot scripts
• Aliases
• Positional parameters
• Command substitution

Conditional statements

• If statement
• Extended if syntax
• Comparison operators

Looping statements

• While statement
• Until statement
• Iterating for loop
• Break and continue

Mathematics

• Let statement
• Arithmetic command
• Arithmetic value command
• Counting for loop
• C Mathematics

Variables

• String length
• Substrings
• Deleting leading and training strings
• Providing default values

Shell IO

• File descriptors
• Redirecting input and output
• Inline documents
• Opening file descriptors
• Reading and writing file descriptors
• Closing and moving file descriptors

Functions

• Function definitions
• POSIX functions
• Positional parameters
• Returning a value
• Local and reference variables

Signal Handling

• UNIX Signals
• Sending signals
• The trap statement

User Input

• Using getopts
• The select statement

Applications

• Hiding parameters
• Database Queries