The Writers Perspective

PHP doesn’t spring to mind when thinking about processing XML data, but PHP is a better solution than you might think. Since PHP is used to develop websites, which use HTML a standard based on the principles of XML, PHP is a sensible choice. PHP also includes powerful tools for parsing and manipulating XML data. We can use this to our advantage to convert and manipulate XML information in our PHP based web applications. XML-RPC and SOAP also use XML, so the use of a web-based language for web-services is also another obvious choice.

All of these situations are covered in extensive detail by Thomas Myer in his new book, No Nonsense XML Web Development with PHP from publisher SitePoint, a long time source for articles and information on web applications and development.

The contents

No Nonsense XML Web Development with PHP covers a gamut of different topics, from an introduction on the basics of XML and its uses through to web services. Throughout, the straightforward and relaxed tone of the book help you to pick up the background behind what Thomas is teaching you, as well as the specifics of different aspects in the book.

We start off with a simple examination of XML and the role of DTDs in the consistency of the XML data. Thomas is right here to point out that DTDs are about consistency, rather than restriction, on the information we store in XML. He also covers the role that DTDs have in validating information, often simplifying the code required in our application to confirm the quality of the content.
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Getting users to try Linux is only half the battle. The other half is showing them what they can achieve when using it. Linux Made Easy by Rickford Grant uses a task based approach to show how you can use Linux to perform your daily tasks; email, browsing, letter writing, even scanning and printing are covered in detail. I spoke to Rickford Grant about the book, why he chose Xandros and how the look and feel of the computing environment are more important to acceptance than the name on the box.

The book highlights how easy it is to do your everyday tasks – email, writing letters, scanning documents – using Linux. How key do you think this is to the wider adoption of Linux?

I can’t help but think that it is extremely important. Until now, the image of Linux has been of a system for people on the geekier side of the compu-user spectrum, and I’d say the majority of books out there on the subject bear this out with their focus on networks, commands, and so on.

One of the reasons I wrote my first book, ‘Linux for Non-Geeks,’ and now ‘Linux Made Easy,’ was that most of the Linux books out there are so focused on that more geekish facet of Linux that it was hard to imagine a mere mortal having any reason to use Linux, let alone being able to do so. They certainly had that effect on me when I first got started.
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Linux Made Easy by Rickford Grant is a companion to his original Linux for Non-geeks. Where the two differ is that this book is about how easy Linux can be for performing a myriad of tasks using a simple, skill-based approach. In this book, Rickford describes how to use Linux to do what you need to do: web browsing, sending email, basic document creation and using external peripherals like your printer, USB flash drive and scanner. In short, this book is about using Linux, from the perspective of ‘Your Average Joe’.

The book covers, and indeed includes, Xandros Open Circulation Edition, a Debian based distribution that just happens to include a number of key components for the target market, including OpenOffice, a key part of the toolkit required by many users to provide word processing and spreadsheet facilities.

The contents

In consideration of the target audience the book is a meaty, but not imposing, 450 pages making it look both substantial enough to keep potential readers interested and yet not so large as to make them think twice about buying a ‘professional’ book.
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Apache has been a stalwart of the Internet for some time. Not only is it well known as a web serving platform, but it also forms a key part of the LAMP (Linux-Apache-MySQL-Perl/Python/PHP) and is one of the best known open source projects. Getting an Apache installation right though can be tricky. In Pro Apache, Peter Wainwright hopes to help readers by using a task, rather than feature based, approach. I spoke to Peter about Apache, its supported platforms, the competition from IIS and his approach to writing such a mammoth tome.

Inflammatory questions first – Unix or Windows for Apache?

Unix. To be more precise, BSD, then Linux, then almost anything else (e.g., commercial Unixes), then Windows — if you must.

The usual technical arguments and security statistics against using Windows are readily available from a number of sources, so let me give a rather different perspective: it seems Microsoft was in discussion to buy Claria, creators of Gator (one of the more annoying strains of adware that infest Windows desktops). Coincidentally, Microsoft’s beta ‘AntiSpyware’ tool recently downgraded Claria’s products from quarantine to ignore. It seems that the deal fell through, but for reasons of bad PR rather than any concern for the customer. Call me cynical if you like, but I see little reason to place my faith in a closed-source operating system when the vendor is apparently willing to compromise the security of its customers for its own business purposes. Yes, plenty of us already knew that, but this is an example even non-technical business managers can grasp.
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Note: This review was originally published in Free Software Magazine

If you use a free software operating system or environment, chances are one of your key interfaces will be through some kind of shell. Most people assume the bulk of the power of shells comes from the commands available within them, but some shells are actually powerful in their own right. Many of the more recent releases being more like a command line programming environment than a command line interface. “From Bash to Z Shell” published by Apress, provides a guide to using various aspects of the shell. From the basic command line interaction through to the more complex processes of programming, it touches on file pattern matching and command line completion along the way.

The contents

Shells are complicated – how do you start describing working with a shell without first describing how the shell works, and don’t you show them how to use it by doing so? The book neatly covers this problem in the first chapter with what must be the best description of a shell and how the interaction works that I’ve ever read.
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GNU Emacs has been the editor of choice for many users for many years. Despite new operating systems, environments and applications, emacs still has a place in the toolbox for both new and old users. I talked to the authors of Learning GNU Emacs, Third Edition: Eric S Raymond, Deb Cameron, Bill Rosenblatt, Marc Loy, and Jim Elliott about the emacs religion, nervous keyboard twitches and whether emacs has a future in an increasingly IDE driven world.

Well, I guess the answer to the age-old geek question of ‘emacs’ or ‘vi’ is pretty much covered with this book?

Jim Elliott (JJE): We pretty much start with the assumption that people picking up the book want to know about Emacs. I had fun following the flame wars for a while a decade ago, but we’ve moved on. Some of my best friends and brightest colleagues swear by vi.

Bill Rosenblatt (BR): I try not to get involved in theological arguments.

Deb Cameron (DC): Like all religious questions, you can only answer that for yourself.

Eric S. Raymond (ESR): Oh, I dunno. I think we sidestepped that argument rather neatly.

Marc Loy (ML): I think the other authors have chimed in here, but this book “preaches to the choir.” We don’t aim to answer that religious debate. We just want to help existing converts! Of course I think emacs! but I’m a bit biased.

Could you tell me how you (all) got into using emacs?

ESR: I go back to Gosling Emacs circa 1982 — it was distributed with the variant of 4.1BSD (yes, that was 4.*1*) we were using on our VAX. I was ready for it, having been a LISP-head from way back.
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Note: This review was originally published in Free Software Magazine

Linux in Windows World aims to solve the problems experienced by many system administrators when it comes to using Linux servers (and to a lesser extent clients) within an existing Windows environment. Overall the book is meaty and a quick flick through shows an amazing amount of information has been crammed between the covers. There are though some immediately obvious omissions, given the books title and description, but I’m hoping this won’t detract from the rest of the content.

The contents

The book starts off with a look at where Linux fits into a Windows network, covering its use both as a server and desktop platform. Roderick makes some salient points and arguments here, primarily for, rather than against, Linux but he’s not afraid to point out the limitations either. This first section leads on to a more in depth discussion of deploying a Linux system into your network, promoting Linux in a series of target areas – email serving, databases and so on – as well as some strategies for migrating existing Windows desktops to Linux.
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Getting the best performance today relies on deploying high performance clusters, rather than single unit supercomputers. But building clusters can be expensive, but using Linux can be both a cheaper alternative and make it easy to develop and deploy software across the cluster. I interview Joseph D Sloan, author of High Performance Linux Clusters about what makes a cluster, how Linux cluster competes with Grid and proprietary solutions and how he got into clustering technology in the first place.

Clustering with Linux is a current hot topic – can you tell me a bit about how you got into the technology?

In graduate school in the 1980s I did a lot of computer intensive modeling. I can recall one simulation that required 8 days of CPU time on what was then a state-of-the art ($50K) workstation. So I’ve had a longtime interest in computer performance. In the early 1990s I shifted over to networking as my primary interest. Along the way I set up a networking laboratory. One day a student came in and asked about putting together a cluster. At that point I already had everything I needed. So I began building clusters.
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OpenLDAP is the directory server of choice if you want a completely free and open source solution to the directory server problem. Tom Jackiewicz is the author of Deploying OpenLDAP, a title that aims to dissolve many of the myths and cover the mechnanics of using OpenLDAP in your organization. I talked to him about his book, his job (managing OpenLDAP servers) and what he does when he isn’t working on an LDAP problem.

Could you summarize the main benefits of LDAP as a directory solution?

There are many solutions to every problem. Some solutions are obviously better than others and they are widely used for that reason. LDAP was just one solution for a directory implementation. Some people insist that Sony’s BetaMax was a better solution than VHS–unfortunately for them, it just didn’t catch on. The main benefit of using LDAP as a directory solution is the same reason people use VHS now. There might be something better out there but people haven’t heard of it, therefore it gets no support and defeats the idea of having a centralized directory solution in place. Bigger and better things out there might exist but if they stand alone and don’t play well with others, they just don’t fit into the overall goals of your environment.

If you deploy any of the LDAP implementations that exist today, you instantly have applications that can tie into your directory with ease. Because of this reason, what used to be a large scale integration project becomes something that can actually be accomplished. I’m way into standards. I guess LDAP was simple enough for everyone to implement and just caught on. If LDAP existed in the same form it does today but another directory solution was more accepted, maybe I’d be making arguments against using LDAP.

Please read the rest of the interview at LinuxPlanet.

Postfix is fast becoming a popular alternative to sendmail. Although it can be complex to configure, it’s easier to use Postfix with additional filtering applications, for example Spam and virus filters, than with some other mail transfer agents. I spoke to Patrick Koetter and Ralk Hildebrandt about The Book of Postfix, the complexities of configuring Postfix, Spam, and email security.

How does Postfix compare to sendmail and qmail?

Ralf Hildebrandt (RH): As opposed to sendmail, Postfix was built with security in mind.

As opposed to qmail, Postfix was built for real-life systems in mind that have to adapt to the hardships of the Internet today. qmail is effectively unmaintained.

Patrick Koetter (PK): That’s a tough question because I am not one of those postmasters who spent half their life working with Eric Allman’s Sendmail nor did I spent too much time enlarging my knowledge on qmail, so I can’t give you an in detail answer that will really tackle specific features or functionalities.

Let me give it a different spin and try if that answers it:
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