Publisher: O'Reilly & Associates
Authors: Larry Wall, Tom Christiansen, Randal Schwartz
Reviewer: Phil Hughes
Programming Perl is the second edition, updated to cover Perl 5, of “The Camel Book”--the one with a camel on the cover.
This book is not a tutorial. If Perl is your first programming language, you will most likely want to start somewhere else—this book could lead to hopeless confusion.
Rather than the newbie, this book is intended for someone who is at least very familiar with Unix utilities, such as awk and sed, and even better, someone with a language such as C under his belt. In fact, C programmers will see similarities between this book and “K & R”.
Perl Programming begins with an overview of basic concepts. After that, get ready for serious work. The second chapter, titled “The Gory Details”, is exactly that—it covers the whole language in about 100 pages.
The next chapter, which is also about 100 pages, describes the functions available to the Perl programmer. C programmers would think of this as the library. Included for each function is its name, its arguments and a textual description of what it does along with appropriate examples.
The Perl language primarily deals in simple, flat data structures, but this approach doesn't work in every case. Chapter Four describes how to deal with more complicated data by using references and nested data structures.
At this point, less than half way through the book, you have seen all of the language and all the built-in functions. However, if you want to become a truly proficient Perl programmer, there's a lot more to learn; e.g., how to produce good modular code. The book therefore goes on to cover modules and packages as well as interaction with the shell and other languages. This section sets the groundwork for the standard Perl library, which is a set of Perl code included with each Perl distribution, the subject of discussion for 150 pages of the book.
The final two chapters cover debugging and error messages. In addition to how to use the debugger, common mistakes, efficiency and style are covered.
Let me note the humor content—a surprising feature in what should be a dry technical manual on a language—which is generally manifest in explanations of some obtuse detail or presentation of background information. While some might find this distracting, I found it a pleasant diversion from a lot of otherwise necessarily dry material. If a humorous bit is long, it is generally in a footnote that can easily be skipped. My only criticism of this book is that it seems to make Perl seem more complicated than it is. It is hard to put my finger on exactly why I feel this way, but perhaps it is because the book tends to tell you everything about a particular command or capability at once. This is just how the book is organized, and it makes sense for a reference work. In other words, I can't see an alternative presentation format that might improve the book as a tutorial that would not destroy the reference value.
This book is well-written, clear and accurate. While there are close to 650 pages, it contains no fluff. While the Perl language is fairly simple, its real power is in its functions and libraries, which are covered thoroughly. A two-word description of this book is “comprehensive reference”. If you are going to be programming with Perl, this book should be in your library.
Phil Hughes is the Publisher of Linux Journal.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
Free to Linux Journal readers.Register Now!
- SUSE LLC's SUSE Manager
- My +1 Sword of Productivity
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- Non-Linux FOSS: Caffeine!
- Managing Linux Using Puppet
- Doing for User Space What We Did for Kernel Space
- Tech Tip: Really Simple HTTP Server with Python
- Parsing an RSS News Feed with a Bash Script
- SuperTuxKart 0.9.2 Released
- Rogue Wave Software's Zend Server
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide