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Journal: Soylent News 4

Journal by TheRaven64

I've not been posting on Slashdot much this week, because I've been trying out Soylent News, which is using (and old version of) Slashcode (with some improvements) and lacks corporate overlords. It seems to have captured most of what I like about discussions in Slashdot, although is suffering slightly from not having nearly as many active users (50 or so comments is still the norm and it probably needs 100+ to be sustainable).
If you've not visited yet, I'd recommend giving it a go.

I'm TheRaven over there.

User Journal

Journal: Getting a Job 4

Journal by TheRaven64

Someone on Slashdot recently claimed I hadn't read Keep the Aspidistra Flying because I thought the ending was depressing. After I finished my PhD in 2007, I've managed to avoid the same fate and have successfully avoided having a real job for almost five years. I've done freelance programming and written four books, and had a lot of time to post on Slashdot (as you can tell from the fact that, so far, I've posted more than anyone else this quarter) and do open source stuff (Ohloh ranks me in the top 2,000 geeks with no life^W^W^W^Wopen source developers).

That's about to change though. I had two interesting job offers recently (I seem to get job offers from banks very often, but I have a very low tolerance for tedium, so I'd probably have been fired around day 3 if I'd taken any of them). One was from Google in Paris (yay!) but working on boring things (boo!). The other was from Cambridge University, which is about as well paid as you expect in academia (aww!) but basically involves working on the same stuff I do for fun (yay!) with some very intelligent people (yay!). Oh, and it's in a city where a quick search found four tango classes (yay!) and property prices not much lower than London (oops!) and which is both small and flat enough that I can cycle everywhere (yay!) and so does everyone else (look out!).

So, in a few weeks I'm moving to Cambridge. I'll miss looking out at the sea, but being able to dance tango more than once a week should be some compensation. There also seems to be a lively salsa scene, although having to learn yet another set of names for the same Rueda steps is going to be a little tiresome...

When I visited, I went for drinks with some of the makerspace guys the night before my interview (I have no idea how much I drank, but it didn't seem to affect my interview performance too badly...) and met someone who worked on the C++11 atomics spec (which I was in the middle of implementing at the time) and someone who had ported 2BSD to a 32-bit PIC with 128KB of RAM, so it definitely seems like a city with no shortage of geeks...

User Journal

Journal: Wow, I Need to Get a Life 5

Journal by TheRaven64

This weekend (I think, maybe earlier), Slashdot published some statistics about the most active people. Apparently I am in the top four most active commenters for the past month and the past quarter. This is quite depressing.

In happier, and unrelated news, my FreeBSD commit bit was approved this weekend, so I can now cause untold destruction on the Internet at large...

User Journal

Journal: What Phone? 6

Journal by TheRaven64

My current phone is a Nokia N80. I've had it a few years and I'm reasonably happy with it, but it has a fault with the charging circuit and it's pretty bulky, so I'm thinking about replacing it. Unfortunately, there seem to be about 3,000 different options with no competent way of way of working out which one is sensible.

I mainly use my phone as... a phone. So, the most important feature for me is the ability to make and receive calls. Because I am a cheapskate, this includes SIP (and WiFi), since my SIP provider charges a lot less than my mobile provider when calling landlines. I really like WebOS in terms of UI, but that seems to rule the Pre out because the only WebOS SIP client is alpha quality and doesn't integrate with the address book. This is something that Nokia does really well - the SIP client is fully integrated, so I can just select someone from my address book and select Internet Call to make the call. No extra skill required.

Beyond that, the only thing I really need is to be able to sync contacts via bluetooth and to use it as a modem via bluetooth - both pretty standard features, I'd assume, since my last three phones have had them.

In terms of smartphone features, I'm not that bothered. A programming environment that supports native code so that I can port my ObjC runtime would be nice - I have no interest in VM-based crap - but aside from that I don't have any strong requirements.

I would, however, like decent battery life and a small size, and ideally a nice camera. The bulk and poor battery life of my N80 means that I quite often leave it at home.

So, any suggestions?

User Journal

Journal: Midnight Satellite identified (sort of)

Journal by DisownedSky

In this entry, I described something I thought was pretty anomalous. Since then, I've seen something very similar several times. The other day, I managed to get some 10x binoculars on it when it was right overhead. What I saw no longer looked like a point source, but an aircraft with orange lights running down the length of the underside of its fuselage. No running lights on the wingtips that I could discern. This must be some kind of military aircraft, perhaps a tanker, but its odd appearance is simply due to a bright underside light That seems to be roughly omnidirectional in its brightness.

I had hoped for something stranger, but at least there is one less wild goose to chase.

United Kingdom

Journal: Sale of Goods Act beats AppleCare 2

Journal by TheRaven64

A little while ago, someone on Slashdot pointed me at the Sale of Goods Act in relation to purchased electronics. The act, for those unfamiliar with it, requires that goods be 'suitable for the purpose for which sold.' This is a fairly broad term, but it basically means that they must be able to do anything that the seller claims that they can do. Under this law, you have 6 years from the date of purchase to file a lawsuit if the item does not match the claims.

This was relevant to me because my MacBook Pro is now out of warranty and the battery is dying. Looking in the System Profiler, its full charge capacity was showing up as 1476mAh after 56 charges. When new, it was 5500mAh. These numbers don't mean anything by themselves, but Apple claims that their batteries retain 80% of their full charge capacity after 300 charge cycles. Claiming this means that a battery that does not retain 4400mAh after 300 charge cycles is not suitable for the purpose for which sold, and they are legally required to refund or replace it (irrespective of the time that has elapsed, although I can only sue them if they don't within 6 years of the time of sale).

I called their support line and was put through to an Indian woman, who explained that the warranty had expired. I quoted the relevant parts of law to her, and (after being kept on hold for a bit), was transferred to someone senior. He very quickly agreed to send out a replacement battery.

Interestingly, he did not ask that the original battery be sent out, nor that I provide a credit card number where I would be billed if the battery turned out not to be defective. I've had two batteries replaced in warranty, and this was standard procedure then, so apparently I get better service out of warranty. I don't have a great deal of use for a battery that only lasts about 35 minutes on a full charge, but I'll probably keep it as a spare.

As always, it pays to know the law. It's a shame that Apple, which claims to be a customer-focussed company, doesn't educate its support team about this though. Possibly the Indian call centre deals with people from everywhere English speaking, while the Irish one only deals with people in the UK and Ireland, so the people there are more familiar with British law, but if I had not quoted the relevant act then I would have been charged £99 for a battery, on top of the £1.50 it cost to call their support line for half an hour.

User Journal

Journal: So, Farewell, MacMiniColo 1

Journal by TheRaven64

Some time around 2005, Slashdot ran an article about a new hosting company, MacMiniColo that was taking advantage of the new machines that Apple had just released to offer cheap hosting. I got in contact with them, and a little while later, I had a Mac Mini, sitting in a rack somewhere, running OpenBSD and acting as my dedicated server. A 1.42GHz G4 CPU, 512MB of RAM, and an 80GB disk was (and still is) more than adequate for my needs. The biggest load on it is eJabberd, and even that only used under 1% of the CPU.

I had really great service from these people. The hard drive failed a little under a year after I bought the Mini, and Apple refused to honour the warranty because they couldn't find the records of the sale (then, a few weeks later, they could, but by then it was out of the warranty period). MacMiniColo replaced the disk for me at their own expense.

After five years with them, however, I had a little look around and noticed that VPS hosting has gone down in price a lot. I've written a book on Xen, so I thought I might try a Xen-based VPS now that FreeBSD has Xen support.

GigaTux only claims to offer Linux, but I dropped them an email and they were happy to install FreeBSD for me. I still haven't tried the Xen-enabled kernel yet; they installed the stock x86-64 kernel in an HVM domain for me and performance has been fantastic.

I'm sharing a server with 64 other guests and in spite of that performance tends to be better than my ageing Mac Mini. I was getting 1000IOPS while untaring the ports tree, which is far more than the Mini's old 2.5" laptop drive could handle, and is amazing considering that it's going via the slow, QEMU-derived, emulated device, rather than the fast PV driver. I've been installing software from ports, so everything is compiled on the machine, and even that has been fast.

And my Mini? They found someone else who wants it, and offered me about a third of what I paid for it originally - not bad depreciation after five years of constant use. Shipping it back to the UK would have cost almost as much as buying one on eBay, so I sold it on. Hopefully someone else will get some good use out of it.

As an aside, I've been really impressed by how well OpenBSD works on Mac/PowerPC hardware. If you've got an old Mac Mini lying around, chuck OpenBSD on it and you've got a reasonable low-volume server. The newer ones, of course, are x86 hardware, so will run just about anything.

GNU is Not Unix

Journal: Why I don't use GNU/Linux 6

Journal by TheRaven64

There are two reasons why I don't use GNU/Linux: One is GNU, the other is Linux. Of these, the larger reason is GNU, and specifically the glibc part. The most recent reinforcement of this is Ulrich Drepper's inability to read the C specification.

For those not familiar with the C specification, all identifiers that start with an underscore are reserved for the implementation (see section You should never use them in your own code, because your compiler is completely free to do whatever it wants with them. By convention, single underscores are used for global non-standard libc extensions and double underscores are used for compiler builtins.

You can find a number of these in existing compiler. Microsoft exposes SEH with keywords like __try. GCC provides __asm for inline assembly, ICC uses __cpuid for accessing the CPUID instruction, and so on. Clang added __block as a type specifier for their variables that are copied to the heap for use by blocks (closures).

Unfortunately, it turns out that the glibc headers use __block as a parameter name. There are several things wrong with this. One is that they use double underscores at all. By convention, these are reserved for the compiler, while single underscores are reserved for the libc. The second is that they used underscores at all in a parameter. Parameter names are not in the global scope, so they can be anything to prevent name clashes.

The result of this is that, if you use glibc, you can't also use blocks. This is a shame, because we (Etoile) were shipping a working blocks implementation six months before Apple. Well, working on *BSD and Solaris (and probably Windows, QNX and Symbian with PIPS, but not tested there). This problem means that it doesn't work on GNU/Linux.

No problem for me. I only use platforms with libc implementations written by people who can read specs. It may be a problem for some of you, if you use a broken platform with a libc maintained by someone who'd rather salvage his ego than fix a problem, and if it is then I'm sorry for you. My suggestion is that you remember that there are other options.

Operating Systems

Journal: Well, that'll teach me to run betas... 2

Journal by TheRaven64

I saw recently that FreeBSD 8 was in BETA state. I ran 7-CURRENT for a while, because it had features I wanted to test (improvements to the OSS implementation mainly), so I thought I'd give it a try.

This time, rather than doing my usual source install, I tried a binary upgrade using freebsd-update. What a disaster. While the source upgrade procedure uses mergemaster to update configuration files, letting you just keep the new version of files you haven't modified, freebsd-update makes you merge them all by hand where there is a conflict. This wouldn't be a problem, except that all of the config files have a version line at the top, which conflicts between the two versions.

Inevitably, when manually handling the merge for a few dozen files, I missed an important bit so my first boot failed with an error complaining about the diff lines still being in the file. I fixed that, and rebooted.

My next boot failed because one of the startup scripts had replaced an if statement with a case. Unfortunately, this hadn't shown up as a conflict, so it had just taken the start of the case statement and the end of the if, giving nonsense. Fortunately, I was able to find the correct version in CVS and copy it out.

Next boot, my network interfaces weren't working. Actually, this was a problem I'd found earlier. When you update FreeBSD, you update the kernel, reboot, then update the userland (the new kernel is guaranteed to support the old userland, but the converse is not true). The em driver for Intel GigE cards complained that they both had invalid MAC addresses. Not a huge problem; it's a VM so I could just change the kind of virtual network card it was providing to the machine, but checking the bugs database I discovered that it's giving the same error for people with ThinkPads that actually do have this kind of hardware built in. Great.

Finally, my system decided to fail to boot with the error:

mounting /etc/fstab failed, startup aborted

Strange, I thought, I wonder which disk is failing to mount. A quick check in single-user mode showed that everything in fstab had mounted correctly. I eventually tracked this down to a bug in /etc/rc.d/mountcritlocal. This is not present in CVS, so it's probably introduced by the merge process. The value of $? (the exit value from the last command) is stored in $err, another command is run, and then there is supposed to be a switch statement branching on $err, which instead is branching on $?.

I've run betas, release candidates, and even the development branch of FreeBSD before, but 8-BETA2 is the first time I've ever had a FreeBSD install that feels like a beta. The merging done by freebsd-update seems completely broken; it prompted me for things it could have trivially done automatically, but failed to prompt me when it broke random system files. My system is now working again, but it's irritating to have to spend this much effort on an update.

Line Printer paper is strongest at the perforations.