All posts by doffm

Will ‘superphones’ make us more productive?

Every tech company under the sun seems to be pushing new variants of the computer experience on us at CES this year. Smartbooks, Tablets, E-Readers, Smartphones, Netbooks and Notebooks, by the end of 2010 there will cease to be a segmented computing market and consumers are going to have a continuous spectrum to choose from.

Leaving aside how this will muddy the waters when it comes to purchasing decisions, I’d like to concentrate on the most established of the new computing paradigms – the ‘smartphone’. Google can call it a ‘superphone’ all they like, but if its true, then a fruit themed Cupertino company were flying over Metropolis long before they were. The company I work for, Codethink, are considering purchasing smartphones for some of their employees, which has left me wondering if it will make us any happier, healthier or more productive.

Previous size reductions of computing technology have completely shaped the way I work. Over the past two years I have done a full weeks work in: Berlin, Rochester MN, Cambridge UK, North Wales, Manchester, Brighton, and Edinburgh. This is thanks to the availability of small, powerful laptops. It has enabled a whole class of mobile web-workers and I fell for it almost immediately.

I can’t say that hasn’t come without a price, its a ball and chain thats always with you. As software-engineers we tend to love our jobs, take it home with us, sometimes to bed with us, often to the detriment of our well-being. I know that open-source companies have to be pretty mindful of losing people to expectation-stress.

Until now, the smartphone that has become most embedded in business culture is the Blackberry. This has me worried. The Blackberry has so-far been a tool for extending work-hours, convincing employees to stay connected, and stay interrupted. Open-source engineers are already in a state of hyper-connectivity. The moments away from our laptops give us the peace we need for the next day, and extending the flow of information in to that time will lead to a very quick burn-out for us all.

So how will the ‘superphone’ enable me to give-up my laptop? What can I do with it during work hours that will help to streamline my day? As an organisational tool I can’t imagine it will perform better than the computer on my desk, but I may be surprised. Perhaps software for un-obtrusive note-taking will help us ditch the laptop during meetings. Codethink already has a habit of some rather long lunches, maybe this can be turned in to a more productive, but still creative and fun time of the day. Does anyone use some great software that we can’t miss out on?

I know Collabora had the mother-lode of N900′s shipped to them the other week. Collaborans – Is it working out well? :)

Codethink at ELCE 2009

Rob and I took a trip to Grenoble this week for the Embedded Linux Conference Europe meeting. All-in-all a very good couple of days for us. We showed off our research project (daily-catchup) in the demo room on Friday afternoon and got to attend some fantastic talks. Travelling wasn’t so much fun though. Somehow we managed to take 12 hours getting from Manchester to Grenoble. The two pervasive themes at the conference seemed to be boot-time reduction and android.


Jon Masters gave a very good Keynote on Porting Linux. Very interesting to me, Jon gave a great overview of some new things going on in kernel land.


Matt Porter debunks android myths.

The prize winning talk at the conference was entitled “Myth-busters: Android”. Matt Porter talked about his team’s experiences porting android to the Power and MIPS architectures.  It seems that android is not yet a mature technology. Much of the code is ARM specific. Having replaced nearly all of the user-land stack, there is a-lot of configurability and features missing from a more standard linux distribution. I shall endeavour to get hold of the slides so that you can all form your own opinion. For me it was an eye-opener as to just how different android is.


This is the lovely face Rob had immediately after the android talk. If I had to para-phrase the conversation it would be: “Look what they did to our beloved stack”. (Ignored it completely)

The android BOF later in the day helped us all to see some of the really good parts of android. It gave me the feeling that as the platform and community around it matures we will all be able to work with a really great open source product. Just expect a-lot of re-training and re-adjusting along the way.


We demonstrated our daily-catchup research over lunch. The demo table was well attended. Rob and I got to talk about the javascript, vala, tracker, clutter and MVC wizardry that goes into daily-catchup. Its a rich-gui social networking application intended for disconnected operation.


Codethink and the Monta-vista massive.

Tasty dinner on the final evening of the conference. Somehow Rob and I found ourselves out with the Monta-Vista massive. They are a great bunch and made for a wonderful last night in Grenoble.

For a more detailed overview of the conference itself see the free electrons blog.

AT-SPI2 First release

Its been a long time coming, but about a fortnight ago we did the first release of AT-SPI2, the D-Bus port of our Linux accessibility framework. As mentioned in the notes the release had a warning label.

‘DANGER: Development release – may cause psychological harm’

Overall though I’ve been very pleased with the work we’ve achieved so-far. I have not been funded to work on the project for six months now, but I’ve found time to fix a few bugs, and most importantly help out those who want to get involved. I never really believed Linus “Release early, release often”, but it turns out that he  was right. Since the software has had an official release we’ve had a good number of people providing patches and generally poking at it.

Thanks go to Mario Lang, Stephen Shaw, Halim Sahin and others who have tried things out. Its been extremely useful. Mario especially finding a couple of serious bugs.

We still have a long way to go, but the end has been in sight ever since the hack-fest in Dublin. We need to get the cspi port up-to-date, help Mike Gorse work through the issues regarding reference count removal and fix bugs, lots of bugs. With EDS quickly shifting to D-Bus Gnome is well on the way to ORBit removal. A11y and GConf shouldn’t be far behind.

File Organization & Gnome 3.0

Thank-you to Felix Kaser for pointing out Mark Shuttleworth’s interview with It was an incredibly interesting read. While at the GCDS this year I made many guesses about the Ubuntu opinion on Gnome Shell and the plans for 3.0. They, as the largest distributor of a consumer linux desktop, have the most to lose or gain from the awesome 3.0 plans.

The part of the interview that struck me directly was Mark’s opinion on what is missing from our proposals:

Well initially there was a lot of discussions about something that was much less visual which is how files are organized and I even blogged about it. I think actually that could be a bigger  improvement in the every-day user experience of the GNOME desktop”

I don’t know about Mark, but I was surrounded by people who are desperate to solve this type of problem at GCDS. Rob Taylor & Philip Van Hoof were both present and really pushing tracker as a a usable, fast data-store for desktop metadata. I attended Thursdays ontology BoF with the two of them. Mark is right, this is generally an unsexy problem. People who missed the ‘Nature of e-mail containers’ conversation on Thursday afternoon avoided the GCDS nadir of boredom.

The real problems of how we present this to our users is still to come, and its much more difficult than providing a fast data-store or getting consensus on what the meta-data should look like. Still, its the sexy, exciting part where we should be able to get everyone involved. Mark may be surprised by how many at Codethink and elsewhere in the community are working on replacing the awful file-system metaphor for data organization. Obviously we haven’t done enough to get his attention yet, but that could change soon. (Small secret) Codethink should be putting resources into a demo app over the coming months for the purpose of showing off some cool new technologies, including the new Tracker. Wait for a blog post from Rob Taylor for the full details.

Accessibility 3.0

Last week I attended a week-long meeting at the Sun offices in Dublin. The purpose of the trip was to hammer out issues with the D-Bus AT-SPI port, so that everyone can feel more confident about its readiness for Gnome 3.0.

What a great week we ended up having. I should first say thanks to all that attended, Willie Walker, Mike Gorse, Li Yuan, Ke Wang, Brad Taylor, and Rob Taylor. Sun, Novell & Codethink also need thanking. They paid for everyone to be there, some flying from China, with no foundation money involved. The Gnome community is extremely lucky to have Willie devoting his time to accessibility. I dread to think what Gnome a11y would be like without his organization and direction

Willie organized the event, I imagine more out of fear at what he found in the D-Bus AT-SPI code-base than anything else. All told I think everyone was pleasantly surprised. The project will take a-lot of work to get to the level of maturity required, but loads has already been done. What is required of us for Gnome 3.0 isn’t our of our reach.

We started the week with a very brief overview of the design for AT-SPI D-Bus. Only Mike and I had much experience with the project and we wanted to get everyone up to speed.  This very quickly turned into a Q&A session and we figured out what the main issues were on Monday afternoon. Tuesday was spent on the important task of checking the D-Bus protocol specification against both the code and the IDL spec. This bought up a number of bugs, issues and improvements. It was well worthwhile. Amazingly Wednesday & Thursday were spent hacking by everyone, which is a great feat considering that four of us had only peeked at the code previously. So much got done. Orca is now running with a fair degree of success and we can move on to performance issues and application-specific bugs. For a full run-down of the still-to-dos and what-got-dones take a look at the weeks wiki.


Outside of work was great fun also. Dublin really is a beautiful city. Lots of green spaces nice buildings and extremely friendly people. The business park is pretty swanky also, and luckily the Oracle buildings are across the road from Sun. We went out to eat and drink in Temple bar, which apparently isn’t a bar. Wednesday involved a trip to the very very small Novell offices in Dublin. They are a way out of town, Brad and I were lucky to get there at all given the distinct lack of signs and road-names that have changed since Google scraped them. We met up with Alan McGovern, a Moonlight hacker, and along with a meal and a few drinks geeked the night away.  Alberto Ruiz took us all out for a nice meal on Thursday night. I forget where it was. You’ll have to ask him for the recommendation. Later we attended the Sun Pub Quiz. Luckily for me, our arrival was just as the Quiz part was ending. I’m not so good with the questions.

Me for 3.0

What am I doing for 3.0 I hear you ask? I’m sure you didn’t but I’m going to blurt it out anyway. I’ll be finding time any-where I can to work on D-Bus accessibility. Codethink has already dedicated lots of my time to the project, and there may be a little more in the future. The accessibility plan looks a little sketchy in the road-map, but I believe that with some hard work it can become a big success for the big release.


After ranting about my work I’d love to hear what everyone else us up-to. There must me more than a few semi-secret 3.0 charges taking place.

‘Do-ifying’ Gtk (and other applications)

Many thanks to racarr for posting about this earlier today.  I had seen posts on the ‘Do-ifying’ of GTK but they had passed me by. ‘Do-ifying’ applications is a fantastic idea. We shouldn’t limit ourselves to GTK apps though.

The bit that caught my interest was that racarr was thinking of exposing a UI heirarchy over D-Bus to allow Gnome Do to find key-bindings and make them available. I suggested that AT-SPI would be a better way to do this, as all key-bindings are already exposed. I come to no conclusions over whether A11y is the best way. I’m biased. :) It did get me thinking about how A11y technologies could be used to provide general application assistance with Gnome Do.

Context sensitive ‘Do’ commands

Orca, the gnome screen reader, uses a11y mainly by responding to ‘focus’ events which are emitted when input focus moves to a new widget. Gnome Do could use ‘focus’ events to provide context-sensitive commands. By knowing which application, and which part of an application the user is currently focused on it might be possible to provide a more tailored selection of commands.

Perhaps the choice of ‘Do’ commands for each application would depend on finding out what D-Bus interfaces it supports.

Application generated ‘Do’ commands

Obviously for application generated commands we need methods of exposing these to Gnome Do. My preference would be to do this via D-Bus, which again a11y could help with. All ATs (Assistive technologies) need to know when new accessible applications appear on the desktop. Towards this end, D-Bus AT-SPI has a daemon that acts as an application registry and informs ATs when new applications are added. This registry could be made more generic so that Gnome Do would listen for new applications and register their ‘Do’ commands when they are started.

I can’t describe the registration interface here. I don’t know Gnome Do. I’m imagining a list of actions with a command name and descriptions, but it could well be much much more complicated.

Key Bindings

As racarr suggests, it should be possible to inspect the applications UI hierarchy to find all the key bindings and present them and their descriptions to Gnome Do. GOK, the gnome on screen keyboard, already does something VERY similar to this by inspecting an application and presenting all the actions of the currently focused window in a simple manner. There may be other things we can infer from the UI hierarchy, but I wouldn’t want to get too ambitious here.

I’ve often thought that a11y technology was under utilized. As applications on our desktop are already merging together a little by providing and accessing more D-Bus services, a11y seems like it could be well placed to enable some really innovate interfaces for the general user. If this happens it could really help experiences for accessibility users too. More bugs fixed, more descriptions added to widgets with key-bindings. :)

Gnome, KDE & Mono A11y

Congrats Mono A11y

Many congratulations to Mono Accessibility, team for getting their first release out into the open.  The Mono A11y team must be one of the largest open-source A11y groups out there and I’m really excited about the work they are doing. WinForms and Moonlight are not yet my thing, but if Silverlight takes off the UIA provider they have created will undoubtedly form an essential part of Linux accessibility.

I don’t believe that it will be in the first release, but I’m really keen to see work start on the UIA client library for Mono. C# and Mono sound like a great place for developing new ATs.

AT-SPI D-Bus on

For people who don’t know about Gnome accessibility or AT-SPI D-Bus:

AT-SPI D-Bus is a project which aims to use D-Bus instead of ORBit/CORBA as the IPC mechanism for Linux accessibility. For anyone interested in finding out about the Gnome accessibility architecture the developers page has some good information. Oddly enough KDE has a very good Gnome A11y overview, and Sun has a good diagram. Long story short the AT-SPI D-Bus aims to write a new, D-Bus based adapter for ATK, a registry daemon, and client libraries that are API compatible with the existing cspi and pyatspi.

The project has a new home on the servers.

The code-base exists at:  git://

We are keeping a page on the linux-foundation wiki updated with all our progress. Unfortunately I’d say that the code is not yet ready for a first release. For reasons soon evident the code isn’t currently getting the love it deserves. (Help MUCH appreciated)

The reason we chose and the Linux Foundation instead of Gnome hosting is that we wanted to emphasize the cross-desktop possibilities of a D-Bus based accessibility architecture.

Gnome, KDE & Mono: How it all fits together

The Mono A11y architecture diagram is missing something important that the AT-SPI D-Bus project can add – QT accessibility.

The drive to D-Bus accessibility came from ORBit deprecation, the embedded community and an ideal of cross-desktop accessibility. Its the last motive that has me most excited right now. QT currently has a D-Bus framework based heavily off AT-SPI, but unfortunately it has never been taken far enough to be compatible with existing AT-SPI ATs. The reason that the ATK, cspi and pyatspi libraries are not getting my attention right now is that I really want to get started on bringing QT into the mix.

A QT adapter for AT-SPI D-Bus will certainly round-out the Accessibility infrastructure on Linux. Not being involved in the KDE community I don’t have much say on how they do A11y, but I hope to make it as easy as possible for them to choose AT-SPI D-Bus. Along with the Mono work this could mean that QT, GTK, ATK, Winforms & Swing apps are accessible, using the same ATs, in both KDE and Gnome. I think that would be a fantastic achievement. If we work hard enough accessibility could be one of the big success stories of a joint Akademy/Guadec next year.

The book meme

I like this meme, its a fantastic window into how depressingly geeky we all are.

  • Grab the nearest book.
  • Open it to page 56.
  • Find the fifth sentence.
  • Post the text of the sentence in your journal along with these instructions.
  • Don’t dig for your favorite book, the cool book, or the intellectual one: pick the CLOSEST.

“Some learned people are intelligent.”

From “Mathematics for the Nonmathematician” by Morris Kline. This is actually an excellent book supposedly for non-science majors to learn about mathematics. In reality its a very nice read on the history of mathematics, with some problems thrown in.

The choice of this book was a grey area according to the rules. The closest was a copy of Nature Genetics, but this is published in volumes and so started at page 700. The next closest was a stack of books, the top one being the latest Buffy comic. I’m not sure comics count. Can anyone make a firm decision about that?

D-Bus Accessibility – Its alive(ish)

This may not look like much more than another screen-shot of Accerciser. You’ll have to trust me that is Accerciser inspecting firefox-2 over D-Bus. Its the first visible step in a long project aiming to replace ORBit with D-Bus for the AT-SPI accessibility protocol.


Mike Gorse and I have been hacking on this for a little over four months now, and its been pretty slow going. I’m very happy to finally have something to show for it.

So much to do…

What we have however isn’t quite the finished article. One of the main goals of the project is to help bring together Gnome and KDE accessibility. I believe that QT already has an ATK implementation, but I think it would make more sense for the QT accessibility interfaces to meet directly with the AT-SPI D-Bus protocol, a project that has not-yet begun.

On the ATK-Bridge / Pyatspi side there is still a huge amount of testing and bug fixing to do, along with a fair few missing features.

So much to test…

Its testing thats really occupying my thoughts at the moment. A while back, on a linux-foundation conference call, I remeber a conversation about how to test the pyatspi and cspi interfaces.

The conclusions were:

  • Have lots of small applications, each exposing only a few accessible objects and concentrating on a single accessible interface, such as the Component or Image interface.
  • Have a unit test written for cspi or pyatspi that is partnered with one of the mini applications, and inspects it over the AT-SPI protocol.

I have made a poor attempt to unit test pyatspi in this way, but I found it was a-lot of work to get any coverage. I think this is down to my choice of implementing a dummy ATK framework to create the applications. Mini GTK applications would have done just as well.

The advantage of lots of these mini applications and unit tests is that when someone comes to implement the AT-SPI protocol with a new widget set, or with new client side bindings they have something simple to validate against.

Where to go

The repository for the D-Bus AT-SPI work is still on the Codethink servers. It won’t be there for long though, there are plans for the project to be hosted at soon.

A week in the life of a braindead hacker

Help needed

There was some discussion this week on desktop-devel about turning ‘Assistive technologies’ on by default in Gnome. See Willie Walkers original e-mailRob Taylor and I had discussed this previously, and at the time I didn’t have much of an opinion either way. After reading Willie’s e-mail though I was firmly in favor.

However Willie stumbled across a possible performance problem when accessibility is turned on. Using gtk-demo to test memory usage ‘top’ shows that accessibility can increase the ‘DATA’ memory section by 15mb, or over double the memory consumption. This was pretty shocking to me, so I tried to use massif to find the cause.

Thing is, massif reports that the memory allocation is not greatly increased by turning accessibility on.  The maximum stack size is not increased either. The ‘DATA’ field of ‘top’ apparently reports the DRS, or data resident set. The number of pages used by both the stack and heap. Rob suggested that fragmentation could be the problem, but in general I’m pretty stumped as to what is causing the discrepancy.

Help and suggestions greatly appreciated :)

Conduit conversations

We have John Carr in the office now. (Infact he’s been there more than Rob and I this week.) This means lots of conduit discussions. I was treated to a crash course on Conduit internals that left my brain feeling like a squeezed sponge, wrung cloth, and juiced orange all at once. This syncing thing is terribly hard and John has some difficult use cases that he wants to make work. (Tranferring contacts from his laptop go to GMail, and from GMail to the N810 and from that to his laptop. Whew.) Good luck to him. I think its the ‘Brain the size of texas’ award if he manages it.

The rest of the week…

Rob probably can’t blog to tell you this because he is gibbering somewhere in the corner muttering “Reference, Reference, where art thou?”. He’s been debugging lifecycle issues for a fortnight now. Its left us vowing never to touch ‘C’ again whenever humanly possible. (Which is not very often).

I have been working hard on the D-Bus version of pyatspi. Its going much slower than hoped, but i’ll get there in the end. I have a holiday coming this week, a trip to Finland for a friends wedding. I’m really looking forward to it. Were going to have a week of saunas in Lapland.