Classic Shell Scripting Reviews

• This might be a great second book on shell scripting.

  
  By A329TQLDBZDAAF on 2005-06-05
  This might be a great second book on shell scripting. Can serve as a valuable add on to "Learning Korn shell" from O'Reilly -- also a very strong book on shell scripting.
  
  The authors provide a lot of interesting and useful information that is difficult to find in other books. They devoted Ch 5 to piping and in 5.4 "Word List" they discuss famous Doug McIlroy alternative solution to Donald Knuth program of creating the list of the n most-frequent words, with counts of their frequency of occurrence, sorted by descending count from an arbitrary text file.
  
  The authors discuss many Unix tools that are used with shell (Unix toolbox). They provide a very good (but too brief) discussion of grep and find. Discussion of xargs (which is usually a sign on a good book on scripting) includes /dev/null trick, but unfortunately they do not mention an option -0n with which this trick makes the most sense.
  
  One of the best chapters of the book is Ch. 13 devoted to process control. Also good is Chapter 11 that provides a solution to pretty complex and practically important for many system administrators task of merging passwd files in Unix. It provides a perfect insight into solving real sysadmins problems using AWK and shell.
  Shortcomings are few. in "5.2. Structured Data for the Web" the authors should probably use AWK instead of SED. Also XML processing generally requires using a lexical analyzer, not regular expressions. Therefore a tag list example would be better converted to something simpler, for example generating C-tags for vi.
  
  
  

• Book Review: Classic Shell Scripting

  
  By A33HTWHZELP37I on 2005-09-09
  Classic Shell Scripting
  Hidden Commands that Unlock the Power of Unix
  By Arnold Robbins, Nelson H.F. Beebe
  First Edition May 2005
  ISBN: 0-596-00595-4
  558 pages, $34.95
  [...]
  
  I found this to be quite a useful book for learning more about Unix/Linux shell scripting. I would consider this one to be an intermediate level text, and complete beginners might be better served by a more simplified book. There are quite a bit of in-depth details included, and many very nice examples and code snippets. Like all O'Reilly books, it is well organized and formatted, and clearly written.
  
  The book opens with a brief history of Unix and how important the shell (and scripting) is to it. There are some comparisons with other programming languages, and why it is sometimes preferable to use a script versus a compiled program. The very basics of how scripts are written and used are also mentioned here, and beginners may want to refer to an additional book for more of the basic instructions.
  
  The next few chapters cover mostly text processing with scripts, including searching, sorting, printing, extracting, and counting methods. Good examples are used, including the use of regular expressions and pipes to increase the power of your scripts. Following this, there are several chapters on more advanced scripting, including how to use variables, loops, functions, standard I/O, redirection, wildcards, using "awk", and working with external files. Extensive example code is provided throughout.
  
  The remaining chapters of the book get into more advanced subjects such as database manipulation, process control, and increasing the security of scripts. Portability and shells other than bash are also discussed.
  
  Perhaps the most interesting part of the book (for me) were the Appendices and other sections at the end. Appendix A is entitled "Writing Manual Pages", and is extremely informative on how to produce and format a valid man page. This is a much more complicated process than I had previously known (can you say "groff"?), and is quite interesting. For anyone who has ever complained about a poor man page, this will give you all the tools you need to write an improved version! :) Appendix B has some excellent in-depth discussion about Unix files and filesystems, including attributes and permissions. Appendix C is a summary of important Unix commands for shell scripting, categorized by function, which is a good quick reference list. Following this, there is an excellent Bibliography that recommends related books for further reading. Finally, there is good Glossary and an Index.
  
  Overall, I found the book to be excellent in it's content and quality. I would recommend that a beginner also find a companion book to more gently introduce the fundamentals of shells and scripting, but this volume is excellent for the intermediate to advanced user. If you want to fully use the power of the Unix/Linux shell, this is a "must-have" book! Well done to the authors and O'Reilly Publishing.
  
  

• Invaluable resource for shell scripters

  
  By A2QT0KPQU671OU on 2005-06-21
  This is the book that I have been waiting for years for. It's classic O'Reilly, but it's better than that. Even the O'Reilly books have fallen short of being truly useful for shell scripting. I think this was primarily because the authors have been thinking more about language fundamentals then about teaching useful things. This book is targeted towards teaching shell scripting through practical application. This is the shell scripting book to get.
  
  

• Practical and useful

  
  By A35294D9V12VRF on 2005-09-19
  Great book. The emphasis is nicely split between actually using the shell itself and the whole supporting cast of unix tools (sed, awk, cut, join, sort etc.) The idea of carefully crafting solutions using the unix toolbox mindset is key. I also like the fact he doesn't try to teach to multiple shells, but first tries to emphasize portability by sticking mainly to a POSIX standard, and only later adds info about non standard shell topics. If I could only have one book on shell scripting, this would be it. The best description is 'Practical'.
  
  

• A good intro on Unix shell scripting and the problems it solves

  
  By A2E3F04ZK7FG66 on 2007-02-16
  The purpose of this handy little book is to help someone who is working with Unix through the labyrinth of tools available and learn how and when to use them. It is important to note what is mentioned in the preface - "Throughout this book, we use the term Unix to mean not only commercial variants of the original Unix system, such as Solaris, Mac OS X, and HP-UX, but also the freely available workalike systems, such as GNU/Linux and the various BSD systems: BSD/OS, NetBSD, FreeBSD, and OpenBSD." I quote the book because the word "Unix" is about as descriptive as the word "car". The intended audience is anyone who is computer literate, already knows how to program, and is regularly faced with diverse problems in the workplace that must be solved with Unix tools. This book should give you a taste of which tool to turn to and when.
  
  This book can be divided basically into two halves. The first half is a tutorial on writing Unix scripts. The book starts with a brief history of the Unix language and the philosophy behind Unix tools. Slowly, each chapter builds up your skill at script writing. You are shown how to differentiate between shells, how to work with text extensively, how to use loops, pipelines, variables, and decision statements, and how to work with files. There are detailed example scripts at every step along the way. By the end of chapter seven, you should know enough about basic shell scripting to be dangerous.
  
  Starting in chapter 8, you are showed more application-related information. First, Chapter 8 shows and discusses some ready-made scripts for some tasks for which there is no out-of-the-box Unix solution. Some of the handy solutions shown are for path searching and automating software builds. Chapter 9 is a crash course on awk, and is aptly named. It is just enough to be dangerous. You learn how to solve common text processing problems with awk, but you'll need more resources to be really knowledgable. Chapter 10 explains the usage of common commands for listing files, modifying their timestamps, creating temporary files, finding files in a directory hierarchy, applying commands to a list of files, determining the amount of filesystem space used, and comparing files. Next there are two applied chapters showing you how to merge several databases and how to perform spellchecking by using scripting. Chapter 13 changes the subject a bit and talks about the concept of processes in Unix and how you can use their statistics to accomplish a number of monitoring and control tasks. Chapter 14 talks about problems you may run into if you try to take advantage of shell-language extensions, while Chapter 15 addresses the issue of writing secure scripts to the extent it is possible to do so. Writing man pages, and the basics of the Unix filesystem are the subjects of the last two chapters of the book.
  
  I would say it is a good modern introduction to the subject of shell scripting and Unix tools and how to use them. It doesn't dive deeply into any particular topic, but it will get you started by broadly introducing you to the problems most Unix script writers and system admins face regularly and how to get started solving those problems. I highly recommend it for that purpose.
  
  
• Carl's review
  By A2QC138ZNJXK9I on 2005-08-02
  Although I have just started reading through the book, what I see so far is interesting. I'm looking forward to writing my own scripts. With this book I feel confident I will be able to.
  I was a bit surprised that C shell is not included.
  
  
• gets the job done
  By AG35NEEFCMQVR on 2005-05-20
  With the rise of languages like Java, with its cool widgets, someone unfamiliar with Unix might not realise that there is a type of programming proceeding quietly in the background. The shell scripting described by the book has been a mainstay of every Unix variant for years.
  
  The book shows how writing a short script can be used to handle a wide range of tasks. Enhanced by the simple syntax of most shells. Very easy to learn. Helped along by a grab bag of programs like sed; so useful that they are now in the standard unix and linux distributions. From the book, you should also appreciate the input/output pipelining offered by many of these utilities and how this makes for powerful and easy to write scripts. The simplicity of piping an output of a program to the input of another. If this seems too obvious, then you've never had to try the equivalent under VMS (say). That operating system had a dreadful notation which made its scripts far harder to write and understand.
  
  The book's subject totally lacks any glamour. But a lot of actual work gets done in these scripts.
  
  
• Okay
  By ACPM0O34AGUWE on 2006-03-11
  I would say this is a pretty good book that covers it's subject very well, buti didn't use it much because i had also bought Unix in a Nutshell, Fourth Edition, which covered the basics and differences between the shells briefly, which was all i needed at the time. but i looked through this and read some stuff that helped and it is a good book if you plan on doing extended shell scripting. it was just a little more than i actually needed
  
  
• Nice overview of Bourne/sh scripting
  By AW6W67NYN5PR1 on 2006-11-16
  This book provides a nice overview of the Bourne/sh shell's commands. I wish there were more examples with complete scripts. Korn shell users might want to consider "Korn Shell: Programs for Your Survival at Work" by Larry L. Smith. Bash users might want to consider "Bash Shell: Essential Programs for Your Survival at Work" by Larry L. Smith. Some of the examples in Randal K. Michael's "Mastering UNIX Shell Scripting" are also helpful.
  
  
• A really fine book
  By A3LCPGMX1BJHCF on 2005-06-06
  I found this book to be useful, accurate, well-written and
  well-organized. The code examples are lucid and clear.
  
  I've written a longer review for (...), but
  all you need to know is that I consider this an excellent
  piece of work.
  
  

• Learning the bash Shell: Unix Shell Programming (In a Nutshell (O'Reilly))
• sed & awk (2nd Edition)
• bash Cookbook: Solutions and Examples for bash Users (Cookbooks (O'Reilly))
• Mastering Regular Expressions
• Unix in a Nutshell, Fourth Edition