Synopses & Reviews
The Korn shell is an interactive command and scripting language for accessing Unix® and other computer systems. As a complete and high-level programming language in itself, it's been a favorite since it was developed in the mid 1980s by David G. Korn at AT&T Bell Laboratories. Knowing how to use it is an essential skill for serious Unix users. Learning the Korn Shell shows you how to use the Korn shell as a user interface and as a programming environment.Writing applications is often easier and quicker with Korn than with other high-level languages. Because of this, the Korn shell is the most often used shell in commercial environments and among inexperienced users. There are two other widely used shells, the Bourne shell and the C shell. The Korn shell, or ksh, has the best features of both, plus many new features of its own. ksh can do much to enhance productivity and the quality of a user's work, both in interacting with the system, and in programming. The new version, ksh93, has the functionality of other scripting languages such as awk, icon, Perl, rexx, and tcl.Learning the Korn Shell is the key to gaining control of the Korn shell and becoming adept at using it as an interactive command and scripting language. Prior programming experience is not required in order to understand the chapters on basic shell programming. Readers will learn how to write many applications more easily and quickly than with other high-level languages. In addition, readers will also learn about Unix utilities and the way the Unix operating system works in general. The authors maintain that you shouldn't have to be an internals expert to use and program the shell effectively.The second edition covers all the features of the current version of the Korn shell, including many new features not in earlier versions of ksh93, making it the most up-to-date reference available on the Korn shell. It compares the current version of the Korn shell to several other Bourne-compatible shells, including several Unix emulation environments for MS-DOS and Windows. In addition, it describes how to download and build ksh93 from source code.A solid offering for many years, this newly revised title inherits a long tradition of trust among computer professionals who want to learn or refine an essential skill.
The Korn Shell is an interactive command and scripting language for accessing Unixr and other computer systems. This work shows how to use the Korn Shell as a user interface and as a programing environment.
"Learning the Korn Shell" is the key to the Korn shell and becoming adept at using it as an interactive command and scripting language. Readers will learn how to write many applications more easily and quickly than with other high-level languages. This newly revised title inherits a long tradition of trust among computer professionals.
About the Author
Arnold Robbins, an Atlanta native, is a professional programmer and technical author. He has worked with Unix systems since 1980, when he was introduced to a PDP-11 running a version of Sixth Edition Unix. He has been a heavy AWK user since 1987, when he became involved with gawk, the GNU project's version of AWK. As a member of the POSIX 1003.2 balloting group, he helped shape the POSIX standard for AWK. He is currently the maintainer of gawk and its documentation. He is also coauthor of the sixth edition of O'Reilly's Learning the vi Editor. Since late 1997, he and his family have been living happily in Israel.Bill Rosenblatt, a recognized authority on digital media technologies, is president of GiantSteps Media Technology Strategies, a consulting firm focusing on technology strategy for content providers and market strategy for digital media technology vendors. He is one of the architects of the Digital Object Identifier (DOI), an emerging standard for online content identification. He is the author of several technical books and a frequent speaker at conferences.
Bill Trippe is president and founder of New Millennium Publishing, a consulting firm specializing in electronic publishing, content management, and SGML/XML technologies. He writes for The Gilbane Report and EContent Magazine, among other journals.
Stephen Mooney is the founder of Mooney and Associates, a consulting firm whose clients include the International DOI Foundation. He chairs the software and Information Industry Association (SIIA) Special Interest Group for Digital Rights Management.
Table of Contents
Dedication; Preface; Korn Shell Versions; Summary of Korn Shell Features; Intended Audience; Code Examples; Chapter Summary; Conventions Used in This Handbook; About the Second Edition; We'd Like to Hear From You; Acknowledgments; Acknowledgments from the First Edition; Chapter 1: Korn Shell Basics; 1.1 What Is a Shell?; 1.2 Scope of This Book; 1.3 History of Unix Shells; 1.4 Getting the 1993 Korn Shell; 1.5 Interactive Shell Use; 1.6 Files; 1.7 Input and Output; 1.8 Background Jobs; 1.9 Special Characters and Quoting; Chapter 2: Command-Line Editing; 2.1 Enabling Command-Line Editing; 2.2 The History File; 2.3 Emacs Editing Mode; 2.4 Vi Editing Mode; 2.5 The hist Command; 2.6 Finger Habits; Chapter 3: Customizing Your Environment; 3.1 The .profile File; 3.2 Aliases; 3.3 Options; 3.4 Shell Variables; 3.5 Customization and Subprocesses; 3.6 Customization Hints; Chapter 4: Basic Shell Programming; 4.1 Shell Scripts and Functions; 4.2 Shell Variables; 4.3 Compound Variables; 4.4 Indirect Variable References (namerefs); 4.5 String Operators; 4.6 Command Substitution; 4.7 Advanced Examples: pushd and popd; Chapter 5: Flow Control; 5.1 if/else; 5.2 for; 5.3 case; 5.4 select; 5.5 while and until; Chapter 6: Command-Line Options and Typed Variables; 6.1 Command-Line Options; 6.2 Numeric Variables and Arithmetic; 6.3 Arithmetic for; 6.4 Arrays; 6.5 typeset; Chapter 7: Input/Output and Command-Line Processing; 7.1 I/O Redirectors; 7.2 String I/O; 7.3 Command-Line Processing; Chapter 8: Process Handling; 8.1 Process IDs and Job Numbers; 8.2 Job Control; 8.3 Signals; 8.4 trap; 8.5 Coroutines; 8.6 Shell Subprocesses and Subshells; Chapter 9: Debugging Shell Programs; 9.1 Basic Debugging Aids; 9.2 A Korn Shell Debugger; Chapter 10: Korn Shell Administration; 10.1 Installing the Korn Shell as the Standard Shell; 10.2 Environment Customization; 10.3 Customizing the Editing Modes; 10.4 System Security Features; Related Shells; The Bourne Shell; The 1988 Korn Shell; The IEEE 1003.2 POSIX Shell Standard; dtksh; tksh; pdksh; bash; zsh; Workalikes on PC Platforms; Reference Information; Invocation Options; Built-in Commands and Keywords; Predefined Aliases; Built-in Shell Variables; Test Operators; Options; Typeset Options; Arithmetic; Emacs Mode Commands; vi Control Mode Commands; Using getopts; Building ksh from Source Code; Korn Shell Web Sites; What You Can Download; Building ksh; AT&T ast Source Code License Agreement; Colophon;