Unix Shell Programming, Third Edition

1. Introduction

It’s no secret that the Unix operating system has emerged as a standard operating system. For programmers who have been using Unix for many years now, this came as no surprise: The Unix system provides an elegant and efficient environment for program development. After all, this is what Dennis Ritchie and Ken Thompson strived for when they developed Unix at Bell Laboratories in the late 1960s.

One of the strongest features of the Unix system is its wide collection of programs. More than 200 basic commands are distributed with the standard operating system. These commands (also known as tools) do everything from counting the number of lines in a file, to sending electronic mail, to displaying a calendar for any desired year.