Category Archives: Opinion

Thoughts on computers and the IT industry.

Opinion

SliMP3

Introduction

It took me over a year to decide to buy a SliMP3 player. I am not normally that indecisive but I just couldn’t figure out why it cost so much. I mean, what does it do? It streams MP3 music across an Ethernet network and connects to the phono sockets on your hi-fi system. How hard can that be? There must be something cheaper or better than the Slim Devices machine! It took me all that time to research the subject and come to the conclusion that there wasn’t. I still think it’s a lot of money for what it does, but I also still think that it’s pretty much unique.

Out of the box

The pictures show a small, black box with a bright florescent display on the front, but, still, it wasn’t exactly as I was expecting. It’s actually smaller than I thought it would be, not that this should be construed as a bad thing. Close up the smoked plastic front and the tiny box have an amateurish, home electronics project feel to them. It does look fine from a distance and the display is, as advertised, very bright, clear and a major selling point for the device as a whole.

SliMP3The package is rounded off by a fairly compact power adaptor and a decent remote control. The buttons are all big enough to press without having to be too careful and some of the important ones are colour coded. The cursor keys are laid out in a convenient and intuitive plus shape but some of the other buttons seem to be placed in the gaps rather than genuinely useful locations.

Setting it up was a doddle. The Perl-based software installed on my iBook with no trouble and on Linux with a well documented change (RedHat misses out an important Perl module in its default install). I have not tried the Windows installer, but the same, simple process apparently works.

With the server software installed, you fire up a web-browser, type in “http://localhost:9000” and point the server at your music collection. That’s pretty much it!

The hardware is, if anything, even simpler to set up. You plug the SliMP3 into a handy Ethernet port, add mains power and connect it to the phono ports on your stereo. When switched on it, by default, goes out to a DHCP server to get its IP address and then by some mysterious broadcast method (I’m guessing) finds your local music server.

That’s a long way of saying that I just plugged the hardware in and it worked first time.

In use

I’m no hi-fi expert. If you want to know whether the SliMP3 is the last word in digital audio I’m afraid I can’t help you. What I can say is that, to my ear, the sound is clear and sharp and any problems I’ve experienced have generally been because of the source MP3 rather than the hardware.

I have nearly 4000 songs encoded currently — a number that’s gradually increasing as I rip more and more of my CD’s — mostly converted using iTunes at 160bps. At this level the interface is still very usable, especially if you know what you’re looking for. For browsing you begin to see the beauty of the iPod’s scroll wheel, but the SliMP3 also has its web interface for when you’re feeling indecisive.

I have had a few problems with music skipping or stopping entirely, but this has almost always been when using my Linux box. That machine is not exactly state of the art any more and the wireless networking is still very flaky so I suspect that these problems are nothing to do with the SliMP3. However, I mention it here just to point out that you do need a reliable network and a reasonable machine for the job.

Conclusion

After using it quite heavily for a couple of months now, I think my initial impressions were not far off the mark. I think it’s a very impressive, easy to use and well thought out machine. It sounds good and the screen means its usable anywhere in the same room. Most of the competition force you to switch on your TV to edit playlists so I consider this to be very important.

On the other hand, I still think it’s expensive for what it is. The bottom level iPod costs just slightly more but that comes with a 15GB hard-disk!

Overall, I still believe that the SliMP3 is the best product of its type currently available. If you listen to a lot of MP3’s and are sick of headphone or small, powered speakers this is the machine for you.

Addendum: Since I wrote this article, in fact just months after buying the hardware, Slimdevices upgraded the SliMP3 and renamed it the Squeezebox. From what I can tell looking at the pictures, the main difference is a newer (more professional looking) case and wireless networking as well as Ethernet. Of course, all this is currently available at less than I paid for my old model! Such is progress with anything computer related…

Opinion

Practical C Programming

Introduction

It sounded like just the kind of book that I was looking for. I wanted a refresher on C since I’d not used it for a while, and some pointers on ‘advanced techniques.’ The blurb on the back looked about right and the fact that O’Reilly published it clinched the sale.

“Practical C Programming” not only plans to teach you C, but also about style, debugging and the software life-cycle.

Content

The book is split into three sections: Basics, Simple Programming and Advanced Programming.

‘Basics’ introduces the language, leaving out much of the fluff and complex bits, but including much on style and ‘process’ — designing, building and maintaining your program. This part of the tutorial is well structured, only introducing new features of the language as and when they are necessary. It does not teach you how to program, rather how to write C. Since you must be able to program before you start the book, I consider the pace to be much too slow. If you already know how to program, why should you have to wait until chapter six before introducing the if statement?

‘Simple Programming’ finishes off what the last section started. It adds most of the more complex bits such as scope, bitwise operators, pointers, floating-point numbers and the C Preprocessor. Of course, the boundary between basic and simple is not well defined, but I would consider the for statement to be basic. This section also includes information on optimising programs which you might have thought would fall under the ‘Advanced Programming’ section.

The final section is much more terse and reference-like than the first two sections. It includes topics such as the difference between ANSI and Kernigan and Ritchie C, more on pointers, portability and some of the more dodgy parts of C such as the 😕 operator and goto statement. It also includes a section on modular programming (again, I would consider this to be in the wrong section) and ‘Programming Adages.’ For the experienced programmer, it is probably this last chapter that is the most useful. Reminders such as avoid side-effects and never put an assignment inside a conditional seem to go against the grain of conventional C wisdom, but are, indeed, correct and very valuable.

Conclusion

‘Practical C Programming’ is not a bad book by any means. Scattered through its 400-odd pages are dozens of useful tips and heuristics, many of which I’ve not seen in print before. It also manages to clarify some oddities, and the example programs are mostly well thought-out and clear.

The C tutorial is not in enough detail to help a true novice and is too chatty and basic for some people, like myself, who just want the facts. The annoying part is that there is a lot of information in there that I didn’t already know, but I almost didn’t have the patience to read it.

It’s also unusual to find a chapter on software engineering in a C book. Oualline has a nice discussion of design, source control and configuration management but it does leave you wondering why it is there. Sure, it’s an important topic, but there are huge books dedicated to this subject. He can not (and does not) even begin to scratch the surface.

What the book lacks is a clear focus. Is the book for a novice programmer? Is it for someone that doesn’t know C? Someone that does know C? Is it a reference? A software engineering guide? The real answer is that it tries to do it all, but only partially succeeds. A nice try but not a must buy.

The facts

Author: Steve Oualline

Cost: Approximately ?24.50 or US$32.95

ISBN: 1-56592-306-5

Buy this book from Amazon.com of from Amazon.co.uk.

Opinion

Oracle PL/SQL Programming

Introduction

The first point to note is that this book is published by O’Reilly. The second point would be that Steven Feuerstein is generally regarded to be one of the worlds leading PL/SQL experts.

Those two point, on their own, were enough to clinch the purchase just over eighteen months ago.

Content

The book is, to say the least, comprehensive. When I first started to use PL/SQL I would never have guessed that there was enough there to write a thousand page book, but there is.

It’s split into seven sections and twenty-six chapters, making it a good reference as well as useful to learn from. Section one, ‘Programming in PL/SQL’ talks about the history, block structure and style. I’m not entirely convinced that ‘programming style’ belongs in a book such as this, but it’s well written, useful and less intrusive than the similar treatment in “Practical C.”

Section two moves onto the ‘meat’ of the language and takes up over two-hundred pages in its own right — longer than the whole of some other texts! Feuerstein covers all this in detail and with great skill, mentioning not only how the language works but also, where appropriate, where it doesn’t work. This kind of honesty seems rare, especially in Oracle Press books!

‘Built-in Functions’ does exactly what you’d expect, and includes a thorough discussion on handling dates, a common area of confusion (I was pleased to find that it’s not just me…).

Parts four and five are, perhaps, the most clumsy sections. The first talks of ‘Modular Code,’ which I don’t see as being so advanced that it requires its own section. And part five discusses the ‘New PL/SQL8 Features’ which, again, don’t necessarily deserve a section on their own. I suppose it made writing the second edition easier…

The last section before the appendices is called ‘Making PL/SQL Programs Work.’ For those not familiar with server-side PL/SQL, let me point out that this isn’t as silly as it sounds. PL/SQL, until recently, had no debugging facilities to speak of. You can’t set break-points or single-step and even outputting trace statements to the screen is not trivial.

However, although the stuff that Feuerstein writes is interesting and might be useful to some, it’s not all it might be. For example, in the section on tracing PL/SQL programs (chapter 26) he talks about Oracle tracing which, if you’ve ever seen, you’ll realise how useless it is much of the time. (If you’ve not seen it before, be warned that you’ll get thousands of lines of very low-level junk for even a simple program.)

Why did he not talk about a tracing library, say, that logs trace messages into the database with a pipe? I ended up writing one myself, based on the information in the book but I’d preferred not to have!

I thought you said you liked it?

If you said that the last section was very negative I wouldn’t be able to disagree with you. However, this is a book that I’ve been using for over a year, not something I got as a review copy and skimmed. I’m still using the book on a daily basis so it must have some merit. I would never have found many of the problems if the book hadn’t been an important and useful reference for all this time.

O’Reilly know how to publish a good technical book. They focus on telling you what you need to know and how it does, should or, indeed, does not work. Feuerstein’s Oracle PL/SQL Programming is one of the better O’Reilly books, so you should be able to guess how highly I rate it.

I first got my copy over a year ago and I’ve spent most of that time on Oracle projects. I have kept this book by my side at all times and only on a few occasions has it not been able to answer my questions. It’s now so well used and grubby that I may be forced to buy a new copy.

The facts

Author: Steven Feuerstein with Bill Pribyl

Cost: $46.95

ISBN: 1-56592-335-9

Buy this book from Amazon.com or from Amazon.co.uk.

Opinion

Software Project Survival Guide

Introduction

For many people here, writing software is, if not a job, then a hobby. Our enthusiasm is a double-edged sword. Our technical knowledge is usually much greater than people who just develop software for a living. This sounds like a big advantage, but it’s not as large as you would have thought.

Let’s have a look in ‘Software Project Survival Guide’ (SPSG) to see what Steve McConnell, famed author of ‘Code Complete’ and ‘Rapid Development,’ has to say on the subject.

The most relevant bit I can find is in chapter two. It’s a project survival test. Out of thirty-three questions, only one (28: “Does the project team have all the technical expertise needed to complete the project?”) is directly related to our ability to effectively code.

That can’t be right, can it?

Content

While you’re still reeling over the consequences of that last paragraph, I’ll slip in some of the dull things that the book has to cover and finish with some of the more glamorous stuff at the end when you’re brain is back in gear.

Some of the most important stuff is ‘management.’ Whether it’s planning, quality assurance, tracking what’s been developed so far or checking on the number of defects, it’s not the ‘techies’ that are the most important.

At first this comes as a shock, but the more you think about it, the more it makes sense. Unless you know what’s going wrong, you can’t fix it. Unless the complete design is documented a team can’t effectively write the software quickly.

Think about Linux kernel development. It obviously work well, but it’s not terribly optimal. The same bug might get fixed several times and there’s not a huge amount of up to date documentation so people have to dive in at the code. For free software this works fine — since the time is usually free, but if you have deadlines and are under contract to deliver a working product on time you’re going to lose a lot of money.

Good bits

McConnell takes the three hundred pages to explain these past two paragraphs in detail. It sounds very dull, but he has a clear, friendly style that makes it, if not entertaining, then not as dull as it might have been.

He splits the project into stages, explains in broad terms what they are and documents each one in more detail in the later chapters. It’s all very clear and logical leaving you in no doubt what stage you’re currently at and what you should be doing for the successful execution of it.

Bad bits

‘Code Complete’ is a book that just about everyone that writes computer programs should read. ‘Software Project Survival Guide’ does not fall into the same category. The book should be read by “anyone who has a stake in a software project’s outcome” according to the preface, but that is only accurate once you define the type of project it covers.

To cut a long story short, if you write software professionally you should read it. It’s probably more use to managers and team leaders, but you can be a better developer if you know the kind of things that need to be done. Besides, almost everyone will be in charge of people at one point and will need a broader picture than merely what the other modules do. (Well where I work that’s true, anyway.)

It covers projects that have a customer whether that’s an internal customer, an external client or people that buy shrink-wrapped software. What it doesn’t cover are software projects like Linux, massive sprawling projects developed because someone is interested in doing it. This is not unreasonable. Half the challenge in a ‘normal’ project is tracking whether you’re running to schedule. If you don’t have a schedule and cost target it doesn’t matter. However, maybe we could take a few hints from the book to ‘streamline’ the process.

Overall

Steve McConnell has done it again. I don’t think that it will go down as a classic like ‘Code Complete,’ but SPSG is an indispensable book for any developer that has any interest in the process and not just lines of code.

The facts

Author: Steve McConnell

Cost: ?22.49

ISBN: 1-57231-621-7

Buy this book from Amazon.com of from Amazon.co.uk.

Opinion

What About Free Documentation?

Introduction

There’s a lot of free or open source software on the net, and much been written about both that software and the process that drives it. Eric Raymond, of course, is currently the main anthropologist although Steven Levy beat him to it and there are many others.

There is also a significant amount of free documentation. One only needs to take a look at the GNU web site (their definition of a free operating system includes free documentation) or the Linux Documentation Project to see that. However, there doesn’t seem to have been a “Cathedral and the Bazaar” for free documentation, or even anything similar.

That’s kind of what I want to do here, but I’m not going to go into as much detail. Instead, I’m going to write about my own experience writing free documentation (my Oracle 8i Installation Howto), the trial and tribulations, the ups and downs, the good times and the bad… You get the idea.

Starting off

I guess the first thing to note is that I didn’t write the HOWTO to ‘scratch an itch’ — I already knew how to install Oracle! Instead, I noticed that many people were having difficulties and that I was spending quite some time replying to the same questions on newsgroups and Oracle Technet. You could say that I wrote the document in order to be just as helpful but without being quite so intensive on my time! (So my itch could have been to save time.)

Another motivator was ‘to put something back into the community.’ Sounds a little pretentious, but it’s true. I’ve been using Linux since 1994 and, although an able developer, have never contributed any code to any free software. This was my chance! I suppose I naively thought that writing English would also take less time than C. As we’ll see later, that didn’t turn out to be the case.

I think that this is an important difference between free software and free documentation. No-one will ever write free documentation to “scratch an itch” (as Eric Raymond so eloquently put it). This takes away, quite possibly, the greatest incentive to create something and may explain why, generally speaking, text is very much a second class citizen to code.

Release early; release often

The first decision I really needed to make was tools to use. My first thought was to add a few new pages to the web site that you’re currently reading. And then I got lazy. I decided to base my new work on the then current Oracle HOWTO, which meant that I had to get to grips with SGML and the SGML-Tools programs. At this point I wasn’t thinking in terms of getting it into the Linux Documentation Project, I just wanted to get a head-start. Once I’d actually started, it didn’t take me long to figure out that the structure of the old document didn’t match what I needed and, more or less, started again from scratch. I did, however, keep the same tools.

Having just read the Cathedral and the Bazaar, I consciously decided to issue my document before it was complete. I quickly wrote the introduction, prerequisites and installation sections and added a number of place-holders for the remaining sections. I then announced it in a message to Oracle Technet and a couple of newgroups.

Very quickly I got some excellent feedback. People were asking for clarifications and new questions, and others were pointing out factual errors. As with software, I quickly added these fixes and thanked the contributers both by email and in the document itself.

I was very pleased that this approach worked. Normally I would have ‘finished’ my work before making any issue, but by releasing early I was able to help more people early on and elicit — I’m guessing here — more useful comments. (I figure that’s true because I think I’d be less inclined to contribute to a finished document than a work-in-progress.)

Maintenance

Around version 1.5, a couple of weeks after my initial release, it was more-or-less complete. All sections were filled in and I managed to complete a successful installation just by following the steps I’d written about.

The first issue was the people didn’t follow my advice — how dare they! Oracle is a big and complicated application and, even on Solaris, you just don’t change things unless you have to and you always use a ‘certified’ operating system. This is an alien mind-set to many Linux developers, who tend to thing “newer is better” and is not helped by all the weird and wonderful devices that you can connect to an Intel-based PC.

The first questions I received that deliberately weren’t answered in the HOWTO were problems with different distributions. People were trying to get Oracle running on just about anything with a Linux kernel!

I didn’t fancy wiping my PC clean and attempting the install with as many different distributions as I could find, I just didn’t have the time. Fortunately, the same community on the Internet that helped me complete my first version added to my knowledge base.

I started to add more and more detail to the HOWTO. If you’re using RH6 do this, with Debian do that… It seriously affected the “flow” of the document for everyone. Given my Oracle (conservative) background, this is just not a problem I originally considered.

When Oracle released 8.1.6 I made the decision that the HOWTO was for RH6 and Oracle 8i R1. It would make the occasional nod to later releases of both the database and the distribution, but fundamentally the focus would be on one version of Oracle and one version of Linux.

As a kind of half-way-house, I started to add extra pages to my website detailing some of the idiosyncrasies of different Linux distributions or newer versions of Oracle. I’m still not completely happy with this approach but I’ve not heard of a better solution yet.

Feedback

Having “completed” my document, what keeps me editing? If I’m writing software, my motivation is adding cool new features. Or maybe adding new stuff for other people and waiting for their praise?

As I mentioned earlier, things are very different for documentation writers.

I’ve got an awful lot of mail about Oracle and Linux since late 1999 when I first published the HOWTO. The email I get seems to have gone through a number of phases. When I first issued the document, I got an almost fifty-fifty split between “thank yous” and suggestions for improvement. Almost all was positive, constructive and friendly.

Without it I would almost certainly have stopped writing. At this point I suppose my motivation was to increase the ratio of thanks to suggestions. I turned a stream of emails into a challenge!

As the HOWTO started to get into wide circulation, the number of helpful suggestions started to drop and the number of questions started to rise dramatically. Some I saw as suggestions as I didn’t cover those details, but most were just from people who clearly couldn’t be bothered to read any further than the front page and my email address.

I can’t count the number of messages I’ve received saying “it didn’t work, what should I do?” (in as many words). How should I reply to that without being rude?! I’ve also received emails from people giving me their “root” password and other confidential details.

The next stage was when Oracle released a newer version and RedHat decided to go with a new version of GLIBC for version 7 of their distribution.

By this point, my motivation was mainly trying to reduce the number of messages I was receiving. Sure, I felt like being rude but I rarely was. I tried to answer all the most common questions in the document, but this point was definitely the low point. Although the updates were helpful, I was doing them for the “wrong” reasons, and the number of messages saying “thanks” had dropped to virtually zero.

More recently I’m only getting the occasional question. It’s difficult to know whether that’s because my HOWTO covers just about everything it needs to or because I’m just not promoting it as much as I used to or because the cutting edge in Oracle is now with 9i. Or maybe I was rude and people are too scared to talk to me..?

In conclusion…

If my original intention was to save time, it failed miserably. I’ve spend even more time replying to emails and maintaining the document than I would have done occasionally adding comments to discussion groups.

Towards the end of this piece I’m sounding very negative, but that’s a bad way to finish as generally speaking it has been very enjoyable. Getting a Linux distribution with your work on is quite a buzz and it’s always nice to get a friendly message or offers of free CDs and books from strangers.

Opinion

Engineer or Hacker?

Eric Raymond would have us believe that everyone that develops software for fun is a hacker. I know that historically this has always been the case, but that doesn’t necessarily make it the right thing. All good, and bad, things come to an end.

I doubt that it will happen any time soon, but I think that ‘hacker’ is a term that should whither and die.

The first problem, and this is the obvious one, is the public perception of it. Yes we all know that hackers write code while crackers break into computer systems, but how many people ‘outside’ know that? How many professional software developers, i.e., those who do it just for a living rather than for fun, know that?

If even professionals don’t know the difference, how can the rest of the population have a chance?

Of course there’s always the fanatical wing, those that claim that we should hit the problem face-on. We should call ourselves hackers because we know that we’re right and that everyone else is wrong.

It’s actually a very politically correct way of doing things, but I remain unconvinced that it works. Richard Stallman continues to insist on the term ‘free software,’ even though most people find it more confusing than ‘Open Source.’ None of this is about changing ideals or opinions, it’s just about the correct marketing of the term.

The second problem I identified is much more subtle. What does the term ‘hacker’ mean? My dictionary defines it as follows:

hack‘ vt cut, chop (at) violently;

It goes on, but that’s the important part. My objection comes from the lack of precision that the term implies. You get a program and violently cut and chop it around until, by chance, you get something out at the end that seems to work okay.

I hope you don’t develop software like that, I certainly don’t. Any half-decent developer follows a process, no matter how ill-documented. When you debug software you don’t just dive in adding ‘print’ statements all over the place, guessing where it goes wrong. Instead you make a hypothesis and test, modifying your original until you get a good idea what’s wrong, then you start with the ‘print’ commands or your debugger.

Does that sound uncontrolled and violent?

All that planning and precision, all the experience that it takes to be able to make a reasonable and accurate hypothesis sounds more like engineering of some kind.

And that it why I call myself a Software Engineer rather than a hacker, even when I write code in my spare time.