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Russell Coker: Android Screen Saving

Tue 29th Jul 2014 23:07

Just over a year ago I bought a Samsung Galaxy Note 2 [1]. About 3 months ago I noticed that some of the Ingress menus had burned in to the screen. Back in ancient computer times there were “screen saver” programs that blanked the screen to avoid this, then the “screen saver” programs transitioned to displaying a variety of fancy graphics which didn’t really fulfill the purpose of saving the screen. With LCD screens I have the impression that screen burn wasn’t an issue, but now with modern phones we have LED displays which have the problem again.

Unfortunately there doesn’t seem to be a free screen-saver program for Android in the Google Play store. While I can turn the screen off entirely there are some apps such as Ingress that I’d like to keep running while the screen is off or greatly dimmed. Now I sometimes pull the notification menu down when I’m going to leave Ingress idle for a while, this doesn’t stop the screen burning but it does cause different parts to burn which alleviates the problem.

It would be nice if apps were designed to alleviate this. A long running app should have an option to change the color of it’s menus, it would be ideal to randomly change the color on startup. If the common menus such as the “COMM” menu would appear in either red, green, or blue (the 3 primary colors of light) in a ratio according to the tendency to burn (blue burns fastest so should display least) then it probably wouldn’t cause noticable screen burn after 9 months. The next thing that they could do is to slightly vary the position of the menus, instead of having a thin line that’s strongly burned into the screen there would be a fat line lightly burned in which should be easier to ignore.

It’s good when apps have an option of a “dark” theme, that involves less light coming from the screen that should reduce battery use and screen burn. A dark theme should be at least default and probably mandatory for long running apps, a dark theme is fortunately the only option for Ingress.

I am a little disappointed with my phone. I’m not the most intensive Ingress player so I think that the screen should have lasted for more than 9 months before being obviously burned.

Related posts:

  1. Maintaining Screen Output In my post about getting started with KVM I noted...
  2. Android Device Service Life In recent years Android devices have been the most expensive...
  3. Cheap Android Tablet from Aldi I’ve just bought a 7″ Onix tablet from Aldi....
Categories: thinktime

Andrew Pollock: [life] Day 181: Kindergarten, startup stuff, tennis and haircuts

Tue 29th Jul 2014 22:07

Zoe had a massive sleep last night. I had her in bed by 7:20pm. She woke up a little before 6am because she'd lost Cowie, and went back to sleep until 7:30am. I had planned to try biking to Kindergarten for the first time in ages, but we got to Kindergarten late enough as it was driving.

I pretty much spent the day studying for my real estate license. I selected finalists for the design contest I'm running on 99designs. If you'd like to vote, I'm running a poll.

I picked up Zoe from Kindergarten and walked her next door to her tennis lesson. She really didn't want to do it this afternoon, and it took some firm encouragement to get her to participate. I'm never sure where to draw the line, but based on the grinning and running around within seconds of her finally joining in, I think I made the right decision. I think the problem was she was too hot. It was quite a warm day today.

The plan after that had been to go back to Megan's house for a play date, but her little sister had come home from day care early, showing signs of conjunctivitis, so we instead went to the local coffee shop for a babyccino with Megan and her Dad. While we were there, I managed to snag an appointment for a haircut for me, and a fringe trim for Zoe, so we headed over there afterwards.

After our haircuts, it was pretty much time to start making dinner, so Zoe watched some TV, and I prepared dinner.

I managed to get Zoe to bed early. It'll be interesting to see if she has another massive sleep again.

Categories: thinktime

Russell Coker: Happiness and Lecture Questions

Tue 29th Jul 2014 21:07

I just attended a lecture about happiness comparing Australia and India at the Australia India Institute [1]. The lecture was interesting but the “questions” were so bad that it makes a good case for entirely banning questions from public lectures. Based on this and other lectures I’ve attended I’ve written a document about how to recognise worthless questions and cut them off early [2].

As you might expect from a lecture on happiness there were plenty of stupid comments from the audience about depression, as if happiness is merely the absence of depression.

Then they got onto stupidity about suicide. One “question” claimed that Australia has a high suicide rate, Wikipedia however places Australia 49th out of 110 countries, that means Australia is slightly above the median for suicide rates per country. Given some of the dubious statistics in the list (for example the countries claiming to have no suicides and the low numbers reported by some countries with extreme religious policies) I don’t think we can be sure that Australia would be above the median if we had better statistics. Another “question” claimed that Sweden had the highest suicide rate in Europe, while Greenland, Belgium, Finland, Austria, France, Norway, Denmark, Iceland, and most of Eastern Europe are higher on the list.

But the bigger problem in regard to discussing suicide is that the suicide rate isn’t about happiness. When someone kills themself because they have a terminal illness that doesn’t mean that they were unhappy for the majority of their life and doesn’t mean that they were any unhappier than the terminally ill people who don’t do that. Some countries have a culture that is more positive towards suicide which would increase the incidence, Japan for example. While people who kill themselves in Japan are probably quite unhappy at the time I don’t think that there is any reason to believe that they are more unhappy than people in other countries who only keep living because suicide is considered to be wrong.

It seems to me that the best strategy when giving or MCing a lecture about a potentially contentious topic is to plan ahead for what not to discuss. For a lecture about happiness it would make sense to rule out all discussion of suicide, anti-depressants, and related issues as they aren’t relevant to the discussion and can’t be handled in an appropriate manner in question time.

Related posts:

  1. Length of Conference Questions After LCA last year I wrote about “speaking stacks” and...
  2. Questions During Lectures An issue that causes some discussion and debate is the...
  3. Ziggy’s Lecture about Nuclear Power The Event I just attended a lecture by Dr Ziggy...
Categories: thinktime

Rusty Russell: Pettycoin Alpha01 Tagged

Tue 29th Jul 2014 18:07

As all software, it took longer than I expected, but today I tagged the first version of pettycoin.  Now, lots more polish and features, but at least there’s something more than the git repo for others to look at!

Categories: thinktime

Brendan Scott: brendanscott

Tue 29th Jul 2014 12:07

The Cabinet Office has announced the adoption of its open standards:

“The selected standards, which are compatible with commonly used document applications, are:

PDF/A or HTML for viewing government documents

Open Document Format (ODF) for sharing or collaborating on government documents

The move supports the government’s policy to create a level playing field for suppliers of all sizes, with its digital by default agenda on track to make cumulative savings of £1.2 billion in this Parliament for citizens, businesses and taxpayers.”

Imagine a world in which there is the possibility of competition for office suites.  One day Australia might join that world too.



Categories: thinktime

Andrew Pollock: [life] Day 180: Kindergarten, recovery and an afternoon play date

Mon 28th Jul 2014 21:07

I was away all weekend with Anshu, so I had to play weekend catch up when I got home this morning. After I'd unpacked the car and sorted out some lunch, I did the grocery shopping, and by the time I'd unpacked from that it was pretty much time to pick up Zoe and Megan from Kindergarten.

On the way home from Kindergarten, Zoe asked if they could go to the playground. I'd been intended to offer them the playground or a ferry ride, so this worked out nicely.

Zoe wanted to ride her scooter to the park, and Megan seemed happy to run alongside her, so this seemed like a win-win situation. There were a few other kids from Kindergarten at the playground as well.

The small world factor struck this afternoon. There was a mother at the playground that I'd seen at pick up time at Kindergarten, who I didn't recognise, so I struck up a conversation with her. It turns out she's the mother of a boy who was in Zoe's swim class last year. I'd previously spoken with her husband at swim school. They were from Melbourne, had had a stint up in Brisbane, returned to Melbourne, decided they liked Brisbane better, and just relocated back again. Their son, Miller, had gone to Zoe's Kindergarten last year as well, and his Dad had had good things to say about it Sarah at Zoe's swim class.

After the stint in the park, we came back home, and Zoe and Megan watched a bit of TV while I prepared dinner, and then Jason came to pick up Megan.

We had a nice dinner, and I got Zoe to bed a little bit early.

Categories: thinktime

Andrew Pollock: [life] Day 177: Bike riding practice, picnic

Mon 28th Jul 2014 14:07

Friday was another loosely planned day. Zoe indicated that she'd like to practice riding her bike, and it was a nice day, so we made a picnic lunch of it.

We went to Minnippi again, and Zoe did pretty well. I used the gentle downhill part of the path this time to give Zoe a bit more momentum, and there were a few brief periods where I let go of the bike completely and she stayed upright. I definitely think she's getting better, and her confidence is improving. Hopefully a few more practices will have her riding on her own.

After she got tired of riding her bike, we checked out the aviation-themed play area. We had some fun alternating between being the "pilot" and the "control tower". We had our picnic lunch up in that part of the park.

Shortly after lunch, another little girl, Lilian, arrived with her mother, and Zoe befriended her, although she didn't want to play with her all that much. I struck up a bit of a conversation with her mother, and when they migrated over to the duck pond, we went as well, as we had some crusts to feed to the ducks.

There was a guy over there with a big loaf of bread, which he was feeding to the ducks unsuccessfully. When Zoe and Lilian arrived, he donated the remainder of the bread to them to feed to the ducks.

After that, we all went to the other play structure for a while.

When Lilian left, we headed back to Cannon Hill to get some more kitty litter and a tennis racquet. We also dropped into Bunnings for a coffee and babyccino. Bunnings has a bit of an indoor play area, so Zoe checked that out too.

It was getting on in the afternoon by this stage, so we headed home and pottered around for a little bit. Zoe watched some TV, Anshu arrived, and then Sarah arrived to pick up Zoe. It was a nice day.

Categories: thinktime

Brendan Scott: brendanscott

Mon 28th Jul 2014 13:07

Getup alleges that someone has copied one of Getup’s videos, then issuing a takedown over the same video in respect of Getup.  With copyright enforcement rhetoric running hysterical for years now it comes as no surprise that the provider of the video site would remove Getup’s video.  Takedown procedures are specifically designed to be swift and effective against allegations, regardless of the justice of the matter.  Given such a lopsided approach to rights, it is surprising that it has taken until now for people to start abusing the system.  It will get worse in the future.



Categories: thinktime

Andrew Cowie: Vale Peter Miller

Mon 28th Jul 2014 11:07

Sad to receive news this morning that a long time friend and colleague, Peter Miller, had passed.

“After fighting cancer for many years, finally lost”. No, not lost; if there was ever anyone who fought the battle of life and won it was be Peter. Even knowing he was at his last days he was unbowed. Visiting him last week he proudly showed us the woodworking plans and cut lists for some cabinets he was making for his wife MT. He had created the diagrams himself, writing C++ code to call manually drive a drawing library, outputting postscript. Let’s see you do architectural drawing without a CAD program. The date on the printout was two weeks ago.

“The world is a less interesting place today,” wrote another friend. No. Peter firmly believed that interest comes from within. The world is there to be explored, I can hear him saying. He taught us to go forth, wonder, and understand. And so we should.

AfC

Categories: thinktime

Sridhar Dhanapalan: Twitter posts: 2014-07-21 to 2014-07-27

Mon 28th Jul 2014 00:07
Categories: thinktime

Andrew Pollock: [life] Day 176: Museum and swimming

Thu 24th Jul 2014 22:07

Today was a pretty chill day, after yesterday's crazy busy one.

Zoe jumped into bed with at 5:40am, but snoozed again until about 6:30am. It was exciting to get up and watch the inverter showing an ever-increasing power production as the sun rose.

I let Zoe choose what she wanted to do, which is code for "I had nothing in particular planned". She chose the museum by bus this morning, so we were out the door by 9am and on a bus not long after.

The museum had never mailed out my new membership cards from a month ago, so I stopped by the tickets desk first to try and sort that out. They were very apologetic, and gave me two free tickets to Deep Oceans show. They're valid until October, so we'll go back and check that out another day.

Zoe mostly just wanted to go to the Science Centre, so after some morning tea, we headed over there. The place was almost totally empty, so we had free run, which was pretty cool. That took us through until lunch time.

I was trying to make the 12:34pm bus home, but we managed to miss it by maybe 20 metres, which was a bit of a bummer. The lady who did the indoor air quality testing was going to come back at some point after 1pm. Fortunately she didn't end up coming until closer to 2pm, so we were fine getting the 1:04pm bus instead.

After she'd been, we briefly dropped in on one of our neighbours on the way out to grab a few things for dinner from the Hawthorne Garage.

Zoe wanted to go to the pool, which was going to be a bit tight, but we made it out to Colmslie for a brief splash around in the pool before I had to get home to put dinner on.

I wanted to get out to a seminar about company boards at 5:30pm, and Sarah was coming around to babysit Zoe for me, so I wanted to get dinner on the table at 5 before I had to leave. That didn't work out quite to plan, so I had to leave with dinner about 15 minutes from being ready.

I managed to order a taxi and get it almost immediately, and it got me into the city within 15 minutes, which was pretty good. On the way home afterwards, I managed to hail a taxi within minutes of leaving the building, so overall, the transport piece worked really well.

The seminar itself was vaguely interesting. I'm curious about getting on a company board, as I think it could be a good use of my experience, and also a non-9-to-5 way of making some income. I'm not quite sure how to get that first board seat though, and exactly what to expect from a time commitment.

Categories: thinktime

Matt Palmer: First Step with Clojure: Terror

Thu 24th Jul 2014 10:07
$ sudo apt-get install -y leiningen [...] $ lein new scratch [...] $ cd scratch $ lein repl Downloading: org/clojure/clojure/1.3.0/clojure-1.3.0.pom from repository central at http://repo1.maven.org/maven2 Transferring 5K from central Downloading: org/sonatype/oss/oss-parent/5/oss-parent-5.pom from repository central at http://repo1.maven.org/maven2 Transferring 4K from central Downloading: org/clojure/clojure/1.3.0/clojure-1.3.0.jar from repository central at http://repo1.maven.org/maven2 Transferring 3311K from central [...]

Wait… what? lein downloads some random JARs from a website over HTTP1, with, as far as far I can tell, no verification that what I’m asking for is what I’m getting (has nobody ever heard of Man-in-the-Middle attacks in Maven land?). It downloads a .sha1 file to (presumably) do integrity checking, but that’s no safety net – if I can serve you a dodgy .jar, I can serve you an equally-dodgy .sha1 file, too (also, SHA256 is where all the cool kids are at these days). Finally, jarsigner tells me that there’s no signature on the .jar itself, either.

It gets better, though. The repo1.maven.org site is served by the fastly.net2 pseudo-CDN3, which adds another set of points in the chain which can be subverted to hijack and spoof traffic. More routers, more DNS zones, and more servers.

I’ve seen Debian take a kicking more than once because packages aren’t individually signed, or because packages aren’t served over HTTPS. But at least Debian’s packages can be verified by chaining to a signature made by a well-known, widely-distributed key, signed by two Debian Developers with very well-connected keys.

This repository, on the other hand… oy gevalt. There are OpenPGP (GPG) signatures available for each package (tack .asc onto the end of the .jar URL), but no attempt was made to download the signatures for the .jar I downloaded. Even if the signature was downloaded and checked, there’s no way for me (or anyone) to trust the signature – the signature was made by a key that’s signed by one other key, which itself has no signatures. If I were an attacker, it wouldn’t be hard for me to replace that key chain with one of my own devising.

Even ignoring everyone living behind a government- or company-run intercepting proxy, and everyone using public wifi, it’s pretty well common knowledge by now (thanks to Edward Snowden) that playing silly-buggers with Internet traffic isn’t hard to do, and there’s no shortage of evidence that it is, in fact, done on a routine basis by all manner of people. Serving up executable code to a large number of people, in that threat environment, with no way for them to have any reasonable assurance that code is trustworthy, is very disappointing.

Please, for the good of the Internet, improve your act, Maven. Putting HTTPS on your distribution would be a bare minimum. There are attacks on SSL, sure, but they’re a lot harder to pull off than sitting on public wifi hijacking TCP connections. Far better would be to start mandating signatures, requiring signature checks to pass, and having all signatures chain to a well-known, widely-trusted, and properly secured trust root. Signing all keys that are allowed to upload to maven.org with a “maven.org distribution root” key (itself kept in hardware and only used offline), and then verifying that all signatures chain to that key, wouldn’t be insanely difficult, and would greatly improve the security of the software supply chain. Sure, it wouldn’t be perfect, but don’t make the perfect the enemy of the good. Cost-effective improvements are possible here.

Yes, security is hard. But you don’t get to ignore it just because of that, when you’re creating an attractive nuisance for anyone who wants to own up a whole passel of machines by slipping some dodgy code into a widely-used package.

  1. To add insult to injury, it appears to ignore my http_proxy environment variable, and the repo1.maven.org server returns plain-text error responses with Content-Type: text/xml. But at this point, that’s just icing on the shit cake.

  2. At one point in the past, my then-employer (a hosting provider) blocked Fastly’s caching servers from their network because they took down a customer site with a massive number of requests to a single resource, and the incoming request traffic was indistinguishable from a botnet-sourced DDoS attack. The requests were coming from IP space registered to a number of different ISPs, with no distinguishing rDNS (184-106-82-243.static.cloud-ips.com doesn’t help me to distinguish between “I’m a professionally-run distributed proxy” and “I’m a pwned box here to hammer your site into the ground”).

  3. Pretty much all of the new breed of so-called CDNs aren’t actually pro-actively distributing content, they’re just proxies. That isn’t a bad thing, per se, but I rather dislike the far-too-common practice of installing varnish (and perhaps mod_pagespeed, if they’re providing “advanced” capabilities) on a couple of AWS instances, and hanging out your shingle as a CDN. I prefer a bit of truth in my advertising.

Categories: thinktime

Andrew Pollock: [tech] Going solar

Wed 23rd Jul 2014 23:07

With electricity prices in Australia seeming to be only going up, and solar being surprisingly cheap, I decided it was a no-brainer to invest in a solar installation to reduce my ongoing electricity bills. It also paves the way for getting an electric car in the future. I'm also a greenie, so having some renewable energy happening gives me the warm and fuzzies.

So today I got solar installed. I've gone for a 2 kWh system, consisting of 8 250 watt Seraphim panels (I'm not entirely sure which model) and an Aurora UNO-2.0-I-OUTD inverter.

It was totally a case of decision fatigue when it came to shopping around. Everyone claims the particular panels they want to sell at the best. It's pretty much impossible to make a decent assessment of their claims. In the end, I went with the Seraphim panels because they scored well on the PHOTON tests. That said, I've had other solar companies tell me the PHOTON tests aren't indicative of Australian conditions. It's hard to know who to believe. In the end, I chose Seraphim because of the PHOTON test results, and they're also apparently one of the few panels that pass the Thresher test, which tests for durability.

The harder choice was the inverter. I'm told that yield varies wildly by inverter, and narrowed it down to Aurora or SunnyBoy. Jason's got a SunnyBoy, and the appeal with it was that it supported Bluetooth for data gathering, although I don't much care for the aesthetics of it. Then I learned that there was a WiFi card coming out soon for the Aurora inverter, and that struck me as better than Bluetooth, so I went with the Aurora inverter. I discovered at the eleventh hour that the model of Aurora inverter that was going to be supplied wasn't supported by the WiFi card, but was able to switch models to the one that was. I'm glad I did, because the newer model looks really nice on the wall.

The whole system was up at running just in time to catch the setting sun, so I'm looking forward to seeing it in action tomorrow.

Apparently the next step is Energex has to come out to replace my analog power meter with a digital one.

I'm grateful that I was able to get Body Corporate approval to use some of the roof. Being on the top floor helped make the installation more feasible too, I think.

Categories: thinktime

Andrew Pollock: [life] Day 175: Kindergarten, cleaning, swim class and a lot of general madness

Wed 23rd Jul 2014 22:07

Today was ridiculously busy.

I woke up pretty early, but ended up not getting out of bed until about 7:30am. While I was in the shower, the guy from Origin buzzed to get let in because he wanted to replace the building's hot water meters. Then I raced next door for my chiropractic adjustment.

I got back home, had breakfast, and started cleaning the house, which I mostly finished by 11am, then I biked over for my massage. While I was getting my massage, the solar installer tried calling me because they'd arrived. Fortunately they didn't have to wait too long.

I did a bit more cleaning for 45 minutes, raced out to Grill'D to grab some lunch and then over to Kindergarten to chair the PAG meeting.

After the meeting, I picked up Zoe and Megan, and we went home to see how the solar installers were going.

They were making a spectacular mess, and we didn't have a lot of time before we had to head out again for Zoe's swim class. We drove over to the pool, and discovered a few other kids from Zoe's Kindergarten were in the preceding classes. Zoe's swim school is running a 2 for 1 thing this term because of the cold weather, to try and keep kids enrolled. I figured twice as many swim classes could only help, so jumped at the chance.

Megan was happy to play around while we waited for Zoe to have her class, and then we went home again. The solar installers were just finishing up.

No sooner had they walked out the door and the woman I'd organised to do indoor air quality testing arrived. I'm wanting to rule out living on a busy road having any contribution to Zoe's suspected asthma.

I was making a new Thermomix recipe for dinner, and Laura was coming over for dinner after she picked up Megan's little sister from day care. Dinner turned out really well, but with all of the preceding madness, I didn't get it started until a bit later than I had hoped, and so it was on the table later than I'd have liked.

Once Laura left with her kids, I chucked Zoe in the shower and got her down to bed only about 20 minutes later than normal. She slept through the night last night for Sarah, so I'm hoping she'll sleep through the night again tonight.

Categories: thinktime

Matt Palmer: Per-repo update hooks with gitolite

Wed 23rd Jul 2014 15:07

Gitolite is a popular way to manage collections of git repositories entirely from the command line – it’s configured using configuration stored in a git repo, which is nicely self-referential. Providing per-branch access control and a wide range of addons, it’s quite a valuable system.

In recent versions (3.6), it added support for configuring per-repository git hooks from within the gitolite-admin repo itself – something which previously required directly jiggering around with the repo metadata on the filesystem. It allows you to “chain” multiple hooks together, too, which is a nice touch. You can, for example, define hooks for “validate style guidelines”, “submit patch to code review” and “push to the CI server”. Then for each repo you can pick which of those hooks to execute. It’s neat.

There’s one glaring problem, though – you can only use these chained, per-repo hooks on the pre-receive, post-receive, and post-update hooks. The update hook is special, and gitolite wants to make sure you never, ever forget it. You can hook into the update processing chain by using something called a “virtual ref”; they’re stored in a separate configuration directory, use a different syntax in the config file, and if you’re trying to learn what they do, you’ll spend a fair bit of time on them. The documentation describes VREFs as “a mechanism to add additional constraints to a push”. The association between that and the update hook is one you get to make for yourself.

The interesting thing is that there’s no need for this gratuitous difference in configuration methods between the different hooks. I wrote a very small and simple patch that makes the update hook configurable in exactly the same way as the other server-side hooks, with no loss of existing functionality.

The reason I’m posting it here is that I tried to submit it to the primary gitolite developer, and was told “I’m not touching the update hook […] I’m not discussing this […] take it or leave it”. So instead, I’m publicising this patch for anyone who wants to locally patch their gitolite installation to have a consistent per-repo hook UI. Share and enjoy!

Categories: thinktime

Russell Coker: Public Lectures About FOSS

Tue 22nd Jul 2014 18:07
Eventbrite

I’ve recently started using the Eventbrite Web site [1] and the associated Eventbrite Android app [2] to discover public events in my area. Both the web site and the Android app lack features for searching (I’d like to save alerts for my accounts and have my phone notify me when new events are added to their database) but it is basically functional. The main issue is content, Eventbrite has a lot of good events in their database (I’ve got tickets for 6 free events in the next month). I assume that Eventbrite also has many people attending their events, otherwise the events wouldn’t be promoted there.

At this time I haven’t compared Eventbrite to any similar services, Eventbrite events have taken up much of my available time for the next 6 weeks (I appreciate the button on the app to add an entry to my calendar) so I don’t have much incentive to find other web sites that list events. I would appreciate comments from users of competing event registration systems and may write a post in future comparing different systems. Also I have only checked for events in Melbourne, Australia as I don’t have any personal interest in events in other places. For the topic of this post Eventbrite is good enough, it meets all requirements for Melbourne and I’m sure that if it isn’t useful in other cities then there are competing services.

I think that we need to have free FOSS events announced through Eventbrite. We regularly have experts in various fields related to FOSS visiting Melbourne who give a talk for the Linux Users of Victoria (and sometimes other technical groups). This is a good thing but I think we could do better. Most people in Melbourne probably won’t attend a LUG meeting and if they did they probably wouldn’t find it a welcoming experience.

Also I recommend that anyone who is looking for educational things to do in Melbourne visit the Eventbrite web site and/or install the Android app.

Accessible Events

I recently attended an Eventbrite event where a professor described the work of his research team, it was a really good talk that made the topic of his research accessible to random members of the public like me. Then when it came to question time the questions were mostly opinion pieces disguised as questions which used a lot of industry specific jargon and probably lost the interest of most people in the audience who wasn’t from the university department that hosted the lecture. I spent the last 15 minutes in that lecture hall reading Wikipedia and resisted the temptation to load an Android game.

Based on this lecture (and many other lectures I’ve seen) I get the impression that when the speaker or the MC addresses a member of the audience by name (EG “John Smith has a question”) then it’s strongly correlated with a low quality question. See my previous post about the Length of Conference Questions for more on this topic [3].

It seems to me that when running a lecture everyone involved has to agree about whether it’s a public lecture (IE one that is for any random people) as opposed to a society meeting (which while free for anyone to attend in the case of a LUG is for people with specific background knowledge). For a society meeting (for want of a better term) it’s OK to assume a minimum level of knowledge that rules out some people. If 5% of the audience of a LUG don’t understand a lecture that doesn’t necessarily mean it’s a bad lecture, sometimes it’s not possible to give a lecture that is easily understood by those with the least knowledge that also teaches the most experienced members of the audience.

For a public lecture the speaker has to give a talk for people with little background knowledge. Then the speaker and/or the MC have to discourage or reject questions that are for a higher level of knowledge.

As an example of how this might work consider the case of an introductory lecture about how an OS kernel works. When one of the experienced Linux kernel programmers visits Melbourne we could have an Eventbrite event organised for a lecture introducing the basic concepts of an OS kernel (with Linux as an example). At such a lecture any questions about more technical topics (such as specific issues related to compilers, drivers, etc) could be met with “we are having a meeting for more technical people at the Linux Users of Victoria meeting tomorrow night” or “we are having coffee at a nearby cafe afterwards and you can ask technical questions there”.

Planning Eventbrite Events

When experts in various areas of FOSS visit Melbourne they often offer a talk for LUV. For any such experts who read this post please note that most lectures at LUV meetings are by locals who can reschedule, so if you are only in town for a short time we can give you an opportunity to speak at short notice.

I would like to arrange to have some of those people give a talk aimed at a less experienced audience which we can promote through Eventbrite. The venue for LUV talks (Melbourne University 7PM on the first Tuesday of the month) might not work for all speakers so we need to find a sponsor for another venue.

I will contact Linux companies that are active in Melbourne and ask whether they would be prepared to sponsor the venue for such a talk. The fallback option would be to have such a lecture at a LUV meeting.

I will talk to some of the organisers of science and technology events advertised on Eventbrite and ask why they chose the times that they did. Maybe they have some insight into which times are best for getting an audience. Also I will probably get some idea of the best times by just attending many events and observing the attendance. I think that the aim of an Eventbrite event is to attract delegates who wouldn’t attend other meetings, so it is a priority to choose a suitable time and place.

Finally please note that while I am a member of the LUV committee I’m not representing LUV in this post. My aim is that community feedback on this post will help me plan such events. I will discuss this with the LUV committee after I get some comments here.

Please comment if you would like to give such a public lecture, attend such a lecture, or if you just have any general ideas.

Related posts:

  1. Sex and Lectures about Computers I previously wrote about the appropriate references to porn in...
  2. Phone Based Lectures Early this month at a LUV meeting I gave a...
  3. Car vs Public Transport to Save Money I’ve just been considering when it’s best to drive and...
Categories: thinktime

Andrew Pollock: [debian] Day 174: Kindergarten, startup stuff, tennis

Tue 22nd Jul 2014 18:07

I picked up Zoe from Sarah this morning and dropped her at Kindergarten. Traffic seemed particularly bad this morning, or I'm just out of practice.

I spent the day powering through the last two parts of the registration block of my real estate licence training. I've got one more piece of assessment to do, and then it should be done. The rest is all dead-tree written stuff that I have to mail off to get marked.

Zoe's doing tennis this term as her extra-curricular activity, and it's on a Tuesday afternoon after Kindergarten at the tennis court next door.

I'm not sure what proportion of the class is continuing on from previous terms, and so how far behind the eight ball Zoe will be, but she seemed to do okay today, and she seemed to enjoy it. Megan's in the class too, and that didn't seem to result in too much cross-distraction.

After that, we came home and just pottered around for a bit and then Zoe watched some TV until Sarah came to pick her up.

Categories: thinktime

Andrew Pollock: [life] Day 173: Kindergarten and some Debian work

Tue 22nd Jul 2014 13:07

Zoe is still waking up on the early side, thanks to the jet lag. I think she woke up around 5am and jumped into bed with me. At least it's nice and dark.

The drop off at Kindergarten went well. Zoe was happy to see Megan again, and wasn't particularly clingy or anything. I was able to get away relatively quickly.

I spent the day getting stuck into some Debian work, and it was good to be able to use the day for its intended purpose for a change.

Megan's Dad, Jason, has a job this week that makes picking her up from Kindergarten impossible, and her parents asked me if I could pick her up on Monday and Wednesday. Zoe was very excited to have Megan come back for a play date, so I picked up both girls and brought them back home.

It was a pretty easy afternoon really. I let the girls just self-direct themselves, and they did a good job of playing on their own with minimal supervision from me. Megan had made a "portable zoo" at Kindergarten for her stuffed panda. It basically involved a shoe box and a couple of pieces of foam for bars. Her and Zoe spent a chunk of time blinging it up with Zoe's craft supplies.

Megan's Mum, Laura, picked up Megan not too long before Sarah did to pick up Zoe. Anshu arrived in the middle as well.

The jet lag is still seriously kicking my butt in the evenings. I'm hoping it will pass by tomorrow.

Categories: thinktime

linux.conf.au News: Our Call For Papers has closed

Mon 21st Jul 2014 21:07

The Call For Papers is now closed. The last 6 weeks has been very exciting as we’ve watched all of those paper submissions flow in.

To those of you who have submitted a presentation to us - good luck, and thank you! You should hear from us in September whether you have succeeded.

There are more and more wonderful things happening each day.

The LCA 2015 Auckland Team

Categories: thinktime

Francois Marier: Creating a modern tiling desktop environment using i3

Mon 21st Jul 2014 21:07

Modern desktop environments like GNOME and KDE involving a lot of mousing around and I much prefer using the keyboard where I can. This is why I switched to the Ion tiling window manager back when I interned at Net Integration Technologies and kept using it until I noticed it had been removed from Debian.

After experimenting with awesome for 2 years and briefly considering xmonad , I finally found a replacement I like in i3. Here is how I customized it and made it play nice with the GNOME and KDE applications I use every day.

Startup script

As soon as I log into my desktop, my startup script starts a few programs, including:

Because of a bug in gnome-settings-daemon which makes the mouse cursor disappear as soon as gnome-settings-daemon is started, I had to run the following to disable the offending gnome-settings-daemon plugin:

dconf write /org/gnome/settings-daemon/plugins/cursor/active false Screensaver

In addition, gnome-screensaver didn't automatically lock my screen, so I installed xautolock and added it to my startup script:

xautolock -time 30 -locker "gnome-screensaver-command --lock" &

to lock the screen using gnome-screensaver after 30 minutes of inactivity.

I can also trigger it manually using the following shortcut defined in my ~/.i3/config:

bindsym Ctrl+Mod1+l exec xautolock -locknow Keyboard shortcuts

While keyboard shortcuts can be configured in GNOME, they don't work within i3, so I added a few more bindings to my ~/.i3/config:

# volume control bindsym XF86AudioLowerVolume exec /usr/bin/pactl set-sink-volume @DEFAULT_SINK@ -- '-5%' bindsym XF86AudioRaiseVolume exec /usr/bin/pactl set-sink-volume @DEFAULT_SINK@ -- '+5%' # brightness control bindsym XF86MonBrightnessDown exec xbacklight -steps 1 -time 0 -dec 5 bindsym XF86MonBrightnessUp exec xbacklight -steps 1 -time 0 -inc 5 # show battery stats bindsym XF86Battery exec gnome-power-statistics

to make volume control, screen brightness and battery status buttons work as expected on my laptop.

These bindings require the following packages:

Keyboard layout switcher

Another thing that used to work with GNOME and had to re-create in i3 is the ability to quickly toggle between two keyboard layouts using the keyboard.

To make it work, I wrote a simple shell script and assigned a keyboard shortcut to it in ~/.i3/config:

bindsym $mod+u exec /home/francois/bin/toggle-xkbmap Suspend script

Since I run lots of things in the background, I have set my laptop to avoid suspending when the lid is closed by putting the following in /etc/systemd/login.conf:

HandleLidSwitch=lock

Instead, when I want to suspend to ram, I use the following keyboard shortcut:

bindsym Ctrl+Mod1+s exec /home/francois/bin/s2ram

which executes a custom suspend script to clear the clipboards (using xsel), flush writes to disk and lock the screen before going to sleep.

To avoid having to type my sudo password every time pm-suspend is invoked, I added the following line to /etc/sudoers:

francois ALL=(ALL) NOPASSWD: /usr/sbin/pm-suspend Window and workspace placement hacks

While tiling window managers promise to manage windows for you so that you can focus on more important things, you will most likely want to customize window placement to fit your needs better.

Working around misbehaving applications

A few applications make too many assumptions about window placement and are just plain broken in tiling mode. Here's how to automatically switch them to floating mode:

for_window [class="VidyoDesktop"] floating enable

You can get the Xorg class of the offending application by running this command:

xprop | grep WM_CLASS

before clicking on the window.

Keeping IM windows on the first workspace

I run Pidgin on my first workspace and I have the following rule to keep any new window that pops up (e.g. in response to a new incoming message) on the same workspace:

assign [class="Pidgin"] 1 Automatically moving workspaces when docking

Here's a neat configuration blurb which automatically moves my workspaces (and their contents) from the laptop screen (eDP1) to the external monitor (DP2) when I dock my laptop:

# bind workspaces to the right monitors workspace 1 output DP2 workspace 2 output DP2 workspace 3 output DP2 workspace 4 output DP2 workspace 5 output DP2 workspace 6 output eDP1

You can get these output names by running:

xrandr --display :0 | grep " connected"
Categories: thinktime

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