It s the last day of the most awesome linux.conf.au 2009 conference in Hobart, Tasmania. I ve just witnessed the a room full of 500 people sit with baited breath as Linus wielded a set of clippers to shave Bdale Garbee s beard, followed by Bdale (with a razor with 3 more blades than last time he shaved, a tiny bowl of water and a hand-mirror) trying to make it look neater. The LCA twitter feed was up on the projector, and someone rightly observed this whole event was actually pretty weird. There are already pictures on flickr too. However, well done to Bdale for being such a good sport, but it looks like his wife Karen will accompany him next year to make sure he doesn t agree to anything else like this, and supervise the waxing of Rusty s chest :) What s this all in aid of? After the incredible auction for this beautiful picture from Karen, and generous donations at the Penguin Dinner on Wednesday night, the conference has now raised between AU$ 35k and 40k towards the Save the Tasmanian Devil appeal. Around AU$ 1.3k of the nonsensical winning consortium s AU $10.6k bid came from the Collabora folks who were at the dinner, and AU$ 1.2k from Collabora and Collabora Multimedia directly. We were all set to place a winning AU$ 3k bid but then Matthew and Daniel came up with the Bdale shaving scheme, and then things really picked up. I m glad we took part - the lead scientist from the project was really grateful, and I hope the money can make a real difference to their great work. On more mundane matters, I also gave my talk this morning, and my slides (Telepathy slides v2.0 thanks to Marco) are online. I also made a few demos of new awesome stuff you can do with Telepathy (most of the patches are already merged upstream or well on the way):

• Geolocation support (XEP-0080) support in the XMPP backend and Empathy, using GeoClue to find your location and the libchamplain Clutter & Open Streetmap widget to display where your contacts are. Thanks to Pierre-Luc, Alban and Daf for their work here - more details on Pierre-Luc s blog.
• Support for launching file transfers over link-local XMPP from Nautilus using the Empathy plugin for nautilus-sendto. This is already merged upstream but needs a patch to work with trunk Empathy. Thanks to Marco, Jonny and Guillaume for their work on this.
• Alban also made a neat hack to Rhythmbox which allows exporting your DAAP music server to one of your contants over a Telepathy Stream Tube. Thanks also to recent work from Marco, these tubes now go over XMPP s SOCKS5 Bytestreams, giving much better throughput than the earlier in-band implementation, network permitting. The next step is unleashing the full might of our libnice NAT traversal library, signalling tubes with Jingle, and therefore making connections work peer to peer in up to 95% of the cases. However, this won t affect the APIs, stuff will just go faster! Isn t Telepathy wonderful?
• Olivier stepped up to show off the demo from his talk about Farsight, which shows his branch using the new telepathy-farsight library to allow recording Telepathy video calls directly into the PiTiVi video editor. His network was screwed up so it didn t work, but I did see it work in his talk yesterday! Awesome stuff, hopefully Edward and friends can pick it up and merge it in before too long.
• Unfortunately we ran out of time for Will to show off Guillaume s recent work on Telepathy-enabled Abiword on the desktop (rather than just Sugar s Write activity), but I expect he ll blog about it soon!

On that note, these were just the five that I picked to try and fit into my talk. There are a load more demos in the pipeline from the other guys in Collabora of doing stuff with Telepathy, so keep a close look on Planet Collabora for the next cool thing.

(Apologies in advance for the shameless plug.) It s possibly a little late to talk about new year s resolutions, but if anyone is a Facebook user and has given up smoking (or plans to), you might be interested in Quitclock. My brother Alastair is a health editor for the Bupa private health insurance company, and thought of this neat project which was implemented by my housemate Martin Kleppman, and announced at new year. It helps you keep track of how long since you ve smoked, how much money you ve saved, lets you and your friends know how you re doing, and has health tips about the improvements that you can expect from your new-found abstinence. I m not a smoker but hopefully someone will find it useful.

You know it s time to call it a day and write your talk tomorrow when I just upgraded Gtk+, Cairo and Pango to the versions in Debian experimental while I was upgrading some Telepathy packages, and got this the next time I loaded OO.o. Magic. But seriously, anyone got any ideas what s going on? Update: I switched my Debian mirror to .au and downloaded OpenOffice.org 3.0.1~rc2, and installed the Gtk+ and GNOME stuff too, and not only did the fonts came back, but it no longer looks like the 80s. Score! Thanks for the tips. Back to my talk

For everyone at GUADEC, there’s a boat party sponsored by Collabora this evening. Our sponsorship was confirmed after the program was printed so it’s listed anonymously, but it’s mostly sponsored by Collabora, of course with huge thanks to Baris and his team for the organisation, and local sponsors for food and discounted beer. The boat leaves from Kabatas at 9pm today (Thursday). It’s actually pretty close to the 3rd anniversary of Collabora’s incorporation, so I think we could call this our birthday party. :D I gave my presentation earlier today about using Telepathy to make collaborative applications. My slides are available, as well as the apps I demoed, which are the python VNC demo based on telepathy-python’s examples, Elliot’s Tic Tac Tube game, and Guillaume and Alban’s quick hack to Empathy and Vinagre to share your desktop over a stream tube. I was followed up by Senko’s presentation (slides also available) which had an overview of the libraries and APIs currently available to embed Telepathy functionality in applications on the desktop. The talks were all recorded so hopefully some videos will turn up on-line too. Speaking about collaborative stuff with Telepathy, we’re really keen to hear from the authors of applications like Abiword, Inkscape, Vinagre, Jokosher, Tomboy, Gobby, etc, to find out how we can help you integrate with Telepathy, what features you need before you can get started, or just try and convince you that it’s a good idea. :) If you’re at GUADEC, come and grab one of the Collaborans or drop by on #telepathy on FreeNode and tell us what you’d like to do and how we can help. Yesterday after the talks on Soylent and the People project, Travis and I met up with the guys behind the People project (Ali Sabil and Johann Prieur) and some of the Online Desktop team (Owen Taylor and Marina Zhurakhinskaya). We sketched out a way of plugging together Telepathy, People, Soylent and the Online Desktop to deal a lot better with meta-contacts on the desktop, providing “first-class” people objects. It all looks pretty promising and hopefully we’ll all find some time to make moves towards our vision. This afternoon at 3:30pm, Olivier is also presenting our work on Farsight 2, which is really cool stuff and should include some exciting demos of the multi-person video conferencing stuff we’ve been doing. More generally, GUADEC is awesome. I’m having a great time in Istanbul (despite it being pretty hot for a pale-faced Brit like me), and enjoying the sights and sounds of such an interesting city and culture. I’ve caught up with many of the usual suspects (like Lennart, who never turns down the chance to turn up at a conference and sample the local bars and clubs), and had some great discussions.

I’ve got a load of boxes running Debian etch with Xen 3.0.3 with routed networking (rather than bridged, so I can do iptables and reverse path filtering etc in dom0). Since upgrading from Xen 2.x many moons ago, I’ve not known how to configure one virtual interface to have more than one IP. In the meantime, I’ve ended up doing nonsense like providing a VM with two interfaces just to give it two IPs. However, this interacts really badly with reverse path filtering unless you do a bunch of source-routing rocket science in the domU to send out through the right vif. So, I looked at the vif-route script and it seems to support iterating through a space-separated list of IPs, but I was totally unable to find any documentation or mailing list posts explaining how to format the IPs within the formerly-Python key/value Xen domain config file syntax. After a while playing with the parser and various levels of quoting, I found that actually, the correct amount of quoting is none at all, and also uncovered a bug in another script which prevents it from working correctly. In the hope that this might help others using Google and trying to achieve the same as me, here is my recipe for configuring Xen vif devices to have multiple IPs (note that I think this might be specific to Xen 3.0.x, as I believe 3.2.x introduces config files in the S-expression format which is what xenstore uses internally):

1. Configure your VM using this surprisingly obvious, but somewhat dubious syntax (including a second argument just to prove that yes, it really does work like that):
   
vif=['ip=1.2.3.4 5.6.7.8, mac=00:16:3e:01:23:45']

   When parsed into SXP by xm create, this sets the ip value correctly as a space separated list as the scripts expect:
   
(device (vif (ip '1.2.3.4 5.6.7.8') (mac 00:16:3e:01:23:45)))

2. Fix the bug in /etc/xen/scripts/vif-common.sh:
   
--- /etc/xen/scripts/vif-common.sh~ 2008-06-09 01:14:23.065065119 +0100
+++ /etc/xen/scripts/vif-common.sh 2008-06-09 01:11:06.599986274 +0100
@@ -103,7 +103,7 @@
if [ "$ip" != "" ]
then
local addr
- for addr in “$ip”
+ for addr in $ip
do
frob_iptable -s “$addr”
done

3. Set up multi-homed or aliased interfaces as normal in the domU (depending if you’re a ip or an ifconfig kinda guy).
4. Profit!

In the office, Christian has just unwrapped a very carefully packed box containing a bulging tin of Surstr mming. Apparently due to the “unique” smell you have to open it outside, and he’s invited people to come to his house to try it. Now, I’m not keen on various types of fish even at the best of times, so add a year or so of fermentation, and I am very, very scared. In unrelated news, some people in the office have decided to take up vegetarianism.

Last night I thought of a few gadgets which I’d like to have, and although I’m pretty sure you should be able to get hold of them, I had trouble finding anything that looked quite right:

• Alarm clock which makes coffee: I can’t be the only one who finds it hard to bootstrap my days because I have to get out of bed and make the first coffee of the day before I’ve had any coffee. My parents had a machine which was an alarm clock which made tea (very noisily) at the appropriate time in the morning. Surely there should be a similar device which can display the time and make (at least passable) coffee instead? Be it an alarm clock with a sideline in making coffee, or a coffee machine with a built in timer. I’ve noticed some of Gaggia’s bean-to-cup machines claim to have 24-hour clocks, but does that mean they have a timer function? We just don’t know.
• Decent watch with USB storage: I found some watches online last night which had USB storage built in, some with a little USB connector that folded out, some with a mini/micro USB connector on the side, with the idea I could store (maybe parts of) my GPG and SSH keys on it, and maybe a bootable Debian installer/rescue system. The thing is, I have a reasonably nice Timex Expedition watch at the moment which I quite like: it has an electro-luminescent analog display for the middle of the night, and a digital bit for the date, alarms and multiple time-zones. The USB-enabled watches I saw didn’t look that great as watches, but I might be wrong. Does anyone have a watch that features USB storage that doesn’t compromise too much on the watch functionality? Maybe I should just give up on this one and go for the rugged USB stick on the keyring approach.
• Video output over USB: I have a reasonably new HP 2510P laptop which I also use as my main machine at work with a docking station, TFT, keyboard, mouse, etc. However, as a machine for watching DVDs or other videos on at home, it’s a bit on the small side. I have an olde-worlde big flatscreen TV at home (which is not as good as Christian’s flat-screen blueray surround sound movie set-up, but I think I retain the moral high ground on taste in films), but my laptop doesn’t have any video out. Is there a USB 2.0 widget which produces composite or S-Video output which I can feed to my TV, that will work with Linux, or should I just get a scan converter of some sort so I can use the VGA output?

So, answers on a postcard…

Daf blogged earlier about some of the work we’ve done thus far for the One Laptop Per Child project. Tubes (although the picture looks more like snakes if you ask me :D) are a really cool technology which should let the OLPC activity authors just work on their activity, and use D-Bus and Telepathy to take care of the communications. At the moment our implementation for Gabble (Telepathy’s XMPP backend) is pretty rudimentary and sends all data via the server, but this already lets us layer multi-user tubes over XMPP multi-user chat rooms and have it act like a bus where each member of the room is also a D-Bus endpoint. You can export objects, call methods and emit signals just as normal. Next up we’re going to implement them in Salut (the link-local XMPP backend, which we’ll use for communications over OLPC’s mesh networking) using good old TCP for the one-to-one connections, and some of Sjoerd’s more exciting link-local multicast stuff for multi-user tubes. To make tubes work for desktop clients we’re going to go on and look at more advanced Jingle-based ICE NAT traversal stuff. Maybe one of our next ports of call should be raw stream tubes for existing TCP protocols, then we can make a reality from X over Jabber (or whatever other protocol) that Matthew Allum was wondering about. :) I’ve also just stolen Planet Collabora from Daf’s home directory and put it on its own subdomain, so you can add it to your feed readers and keep track of what we’re up to with Telepathy, Farsight and friends.

I’m in Sydney for LCA 2007 this week, and this should also be my debut post on the conference planet. This is the first time I’ve made it to the other side of the world for this conference, and I’m really glad I came. It’s definitely one of the cooler conferences I’ve been to, slickly run and with an excellent programme of talks, so massive congratulations and thanks are due to the organisers and volunteers. The weather’s a stark contrast to the French Alps (I was skiing last week!), although thankfully it’s quite mild at the moment and not gotten too hot for a Pom like me. :D It’s always cool to catch up with people who I’ve not seen for a while, and put names to faces for a whole load of others I’ve not met yet. If you’re around, reading this in time, and interested in the Telepathy VOIP/IM framework, my talk is today (Friday) at 11am. If shameless bribes help, I’ve also got some funky Collabora and Telepathy shirts I need to give away before I head back to the UK. The second bit is that Collabora’s looking for a couple of people to either join us in Cambridge (UK) or work with us as a subcontractor. We’re currently doing loads of cool and totally open source stuff with IM, voice & video streaming and collaboration technologies. We’re looking for people with experience with some/many/all of C, Python, Glib/Gtk, D-Bus, GStreamer and RTP. If you’re interested, send mail to jobs( )collabora.co.uk, or if you’re around at LCA then come and find me if you want a chat.

I’ve been away from the office for a couple of days, but when I got back to Cambridge, Daf and Sjoerd had some pretty cool stuff to show me: These screenshots are taken by using an environment variable to tell stream-engine just to create an xvimagesink for any call, but Daf’s writing a simple pygtk UI which handles embedding the output window into the UI properly and should make placing/receiving calls slightly less mystical. Even so, a graphical video call APP in ~150 lines of python… not too bad if you ask me. :)

We got an OLPC prototype at Collabora last week, and have been playing with the Telepathy VOIP/IM framework on the devices. Using telepathy-gabble’s (our XMPP backend) Jingle implementation, and telepathy-stream-engine with the Farsight GStreamer RTP library, we got a bidirectional voice/video call going pretty quickly using a few lines of python and a bit of hackery (patches to follow :D). We’re going to polish this up into an activity you can install, and also Sjoerd Simons has been working with us on telepathy-salut, an XMPP Link-Local (also known as Rendezvous, Bonjour, iChat, whatever) backend which we’re hoping to also get working as part of the OLPC platform.

Just a quick one, people want food: my Telepathy talk at GUADEC earlier this week was a success by most accounts, and followed up by after-hours talks today with Kai Vehmanen’s on Telepathy SIP, and Yannick Pellet on the IM/VOIP project on the 770. My slides are available for people who missed my talk, and hopefully soon Fluendo will grace us with videos feeds too. For people still around at the conference tomorrow, I’ve arranged a BOF with Martyn Russell for discussing/hacking Telepathy and Gossip stuff. It’s in the museum library room at 11am tomorrow (Friday). Hope to see you there!

I made it to Vilanova on Friday for GUADEC, managed to get settled in to our chalet (I’m glad we opted for one with air conditioning!). After we got them to fix the hot water, I now think it’s pretty decent accomodation for the price, complete with wifi, swimming pool and a well-stocked shop. The only downside I can see is the distance from town. On Friday night we missed the last bus and walked in, which took over an hour and I developed a bad headache by the time we reached the town (we didn’t find the right beach, but stopped in a bar instead). My enjoyment of the walk wasn’t helped by the small children who were out on the street launching fireworks, mortars and other incendiary devices at or near us most of the way. :) Yesterday we hired bicycles to get to the town center which was certainly more fun, but there’s quite a hill on the way back. Also, bus in and taxi back is pretty much cheaper than the cost of hiring bikes here anyway, so I’m not sure I can recommend it as a long-term strategy. We might do it again for the novelty, and it has the benefit of not needing to wait around for a taxi to get back. Even before I made it to the conference venue yesterday, I’ve already met loads of cool people who hack on all sorts of cool software which I use every day, and I’ve recognised lots more people who I’ve not managed to speak to yet. I’ve also realised that we need to do a lot more work to raise the profile of the Telepathy project which I’ve been working on for almost a year now (eek!). It’s a really cool way to get IM and VoIP stuff properly integrated into the GNOME desktop, and everyone should go and check out the website, play with our releases, chat with me and come to my talk on Tuesday. Oh, and if anyone wants a Telepathy or Collabora t-shirt, grab one off me or daf. :)

In the office just now, daf complained at me that he finds it very annoying when people blog about how they havn’t blogged recently. I apologise, although in my defence, the post was mainly about C (I’ve subsequently learnt that -Wextra will warn me about such errors in future, thanks :D). The question is, is this post also annoying because of this meta-blogging property, or can it be excused as meta-meta-blogging? Although, whilst I am talking about my blog, I found that Ross Burton took a reasonable picture of me at FOSDEM (I’m the one on the left, versus Iain Holmes on the right :D), which I’ve cribbed for my photo on the GUADEC speakers list. I was wondering if in exchange for beer (or cake), anyone would like to make me a hackergotchi for my various Planet appearances? I’ve decided with mjg59 that when referring to Web 2.0, the correct pronounciation of RSS is ‘arse‘ (linked to the definition for people to might spell that word wrongly ;), leading to witty concepts such as ‘arse feeds’, ‘arse readers’, etc. It amused us in the pub anyway.

I wasted a non-trivial amount of time yesterday debugging code in which I’d accidentally written:

if (...);
   
    ...
   

Is there any situation where if (foo); can achieve something which just foo; couldn’t? Could the compiler not warn about a conditional that contained no code? Aggravating lapses in competence aside, I’ve realised I’ve not blogged for months, so over the next few days I’m going to try and write a little about what I’ve been working on recently.

I put a few ideas on the wiki page for some Summer of Code projects based on getting the Telepathy Framework used on the GNOME desktop. We’ve hacked out a spec for doing most IM & VOIP stuff via D-Bus so that you can add whatever functionality you want into any program like Nautilus, Evolution, Gossip, etc, and share the use of your server connections from wherever in the desktop makes the most sense. We’ve been working hard on our flagship XMPP backend implementation, telepathy-gabble, and Rapha l Slinckx & Adam Lofts have been working on some UI implementations in Python and C#, but we need to get some more people looking at different backends and integrating frontend functionality into the desktop. Get those SoC applications going if you think this sounds cool… :) As well as my ideas, I should also mention I’d be happy to mentor for other deserving ideas such as eikke’s CDIS plans, and I’ve also got some ideas about how cross-program (and cross desktop) music databases should be achieved. I’m particularly keen on helping people with D-Bus related projects because I know that not enough people understand how all this stuff works, so I think it’s worth spending a bit of my time to spread the love (and pain) which I’ve learnt working on Telepathy.

My company, Collabora, is seeking one or two experienced free software developers to hire or subcontract. We are working on VOIP and Instant Messaging software using Glib, D-Bus and GStreamer, and our focus is creating and working on completely open source projects. As well as contributing frequently to D-Bus and GStreamer, our main projects at the moment are the Farsight library for negotiating and setting up GStreamer pipelines for peer-to-peer voice and video streams over a variety of protocols, and the Telepathy framework for allowing IM/VOIP server connections to be implemented as D-Bus services, so that the connections can be shared and integrated into your desktop, exposing the different functions of the servers in the appropriate parts of the UI. If this sounds up your street, drop us a line with a CV and details about relevant experience or free software projects you have contributed to.

According to Jeff, I’ve become a smelly Nokia contractor (the reason he stayed with Luis instead of at Mako’s place in Boston, although I’m sure he was referring to Rob Taylor causing the smell). Part of this entails exchanging project schedules with various managers, where time is often talked about in terms of numbered weeks of the year, like: Foo task will be completed by week 42 of 2005. We ran into some problems with varying definitions of these numbers when exchanging schedules with people running on different platforms. Then we realised that even the software we’re using seems to have different ideas about what’s going on too…

• Outlook and Evolution seem to agree, and define the week as starting on Monday, and the first day of the year is always week 1, even if this results in a truncated week. Hence, week 1 of 2006 starts and ends on Sunday 1st January, and then week 2 begins on Monday 2nd, etc. It’s my belief that this is the correct behaviour as defined by some ISO standard somewhere which governs week numbers.
• GtkCalendar gets the week number correct, in that the first day of the year is always in week 1, but varies its definition of the first day of the week depending on your locale. This is presumably so that the display of the weeks is correct, but using it to number the weeks results in bogus week numbers. For me in LOCALE=en_GB it claims that week 1 of 2006 starts on Sunday 1st January, and ends on Saturday 7th January, making my week numbers one lower than the rest of the world.
• Planner uses GtkCalendar for inputting dates, so gets it wrong there as described, but seems to get it wrong in its Gantt chart view in a different way. It has the week starting on Monday, but claims that January 1st 2006 is the last day of week 52 of 2005. This results in week numbers that, match those GtkCalendar give me on weekdays, but differ over weekends, and are still totally bogus when I try and talk about project plans with my managers.

The result is a whole world of pain, and at best causes extreme confusion when we provide documents referring to both dates and week numbers which are inconsistent with each other in their minds, and at worst makes our managers think we’ll have things done a week sooner than we do. I’m not using Evolution at the moment for calendaring stuff, so I can manage if I remember to add one to all my 2006 week numbers when interacting with managers based on GtkCalendar and Planner, but this all seems to be horribly broken. I really don’t want to have to do this for the whole year.

Whilst I can’t claim to have done anywhere near as much for Gaim as Christian Hammond has, I did contribute to Gaim some time ago, and for my efforts I managed at least to attain the status of “Crazy Patch Writer”. However, I gave up trying to contribute to Gaim about three years ago. After starting out as the Debian package maintainer, and one of the founders of #gaim (yes, I know, I’m sorry, it wasn’t always like that), I spent about two years submitting patches which were ignored by almost all of the developers, being forced to beg people with access (including the support/bug triaging guy, who doesn’t really code C) to review and commit them. At the time, nobody was being given CVS access because of a recalcitrant and unresponsive former developer holding the reigns of the Sourceforge project. A few developers came and went, and in what I thought was a miracle, the now lead developer was made an administrator of the Sourceforge project and gradually started handing out access to other people who had been contributing. Except… I was passed over time and time again, and other contributors who had around for less time than myself were given access. I could accept this if I was given some justification, but I was ignored when I asked about getting CVS access and never given any reasons, despite having contributed hours and hours of my time and helped rewrite and clean up sizeable chunks of code. It actually had me close to tears on several occasions, and still upsets me a huge deal that no explanation was ever offered to me. After starting out with packaging work in Debian, Gaim was the first project where I became involved with actual development, and I learnt a great deal from hacking on it, but when I started at university I decided I’d spent enough time pouring my heart into such an unwelcoming recipient, and I moved on quietly.

Does anyone know of a Thunderbird extension to check for words like “attach” and remind you if you failed to make any attachments? Does anyone know of a way to stop Firefox interpreting Ctrl+W as “throw this window away including the wiki post/bugzilla comment/blog entry you were writing”? It doesn’t need to be mapped to delete word, I just don’t want it to close the entire thing. It’s most upsetting.