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Comment David Edmundson answers your questions (Score 5, Interesting) 754

All of your questions are easily answered by reading the link provided at the top of the article:


Why does the desktop care who's booted it up?

The Init System "We don't care. It doesn't affect us."

logind Allows KDE to provide user-switching features.

Device Management Allows KDE to have access to your mouse and keyboard without root access and without random applications being able to sniff your keystrokes.

Inhibitor Locks Allows KDE to react to notifications like "the system is about to go down" and delay until a condition is met (example: delay a suspend until the lock screen is displayed and all your desktop windows are hidden behind the lock screen).

timedated and Friends Allows KDE to set time and date without root; allows KDE apps to be notified if time and date gets changed. (KDE currently runs a daemon just to watch for time and date changes, and they would like to get rid of this daemon and simplify their code.)

User Units If KDE takes advantage of the "units" in systemd, then when any part of KDE crashes or hangs, systemd will restart the misbehaving part.

that implies they won't work on *BSD at all. Right?

"Projects like [SystemBSD] bring the interfaces we need to BSD and as it gets more stable we should be able to start distributing features."

So really, choice is being taken away clear across the board. Either that or I'm missing something really big which implies systemd is not a strict dependency.

I encourage you to read the whole article and see what big things you are missing.

I don't know about you, but when I read that article I didn't think "Man those KDE guys are idiots, why would they want any of that." It all makes sense to me.

It's easier for me to believe that SystemD has some merit than to believe that all the Debian core developers are idiots, plus all the Ubuntu developers, and now all the KDE developers and for that matter the Gnome developers.

My biggest concerns with systemd are the monoculture of it all, so projects like UselessD and SystemBSD sound great to me. Force the SystemD guys to document and justify everything, and provide alternatives.

Comment "Doc" Smith's utlimate vacuum tube (Score 2) 108

About 70 years ago, E. E. "Doc" Smith wrote a series of books that are wonderful space opera: the "Lensman" series. The space battles just keep escalating throughout the series, getting more over-the-top.

My favorite plot point: they used the principles of a vacuum tube to make a device whose pieces included grids mounted in the asteroid belt, with more in other orbits closer in to the sun. In effect they turned the inner Solar System into one honking big vacuum tube, and created a weapon that could concentrate a significant fraction of the sun's output onto attacking enemy fleets. This was called the "Sunbeam". (Believe it or not, this wasn't the end of the escalation. The battles got even bigger after that.)

When you say "ultimate" vacuum tube, I think that one is pretty hard to top.

P.S. 200-word crossover fan fiction: what would have happened if the Battlestar Galactica reboot show had found Earth, and it was the Earth of the Lensman series?


When I was a teen and read those books, I just enjoyed them, but now I'm thinking that it would take a lot of trust to allow Kimball Kinnison to run around acting as judge, jury, and executioner. As readers of the books, we know that he was vetted as deeply as anyone could be by the Arisians, so he can be trusted with that kind of power; but it would be hard for the ordinary people in the world of the books to trust him that much.

Comment Re:What idiocy (Score 1) 313

I have stated as fact that the fear of individuals possibly carrying firearms and defending themselves is not a significant factor in the criminal mind.

Okay, I misunderstood your point. Duly noted.

Studies have also shown that criminals are deterred if they think their victims might be armed. See the decline in violent crime after concealed carry of firearms became more common:


Knives happen to have sharp edges, so trying to take one away is less of a winning proposition.

I'd really like some citations to go along with these claims you are making.

Hint, what you are saying here doesn't square with what my self-defense instructors have told me. The best single tool for self-defense is a firearm; a knife has a place in self-defense but it is definitely not the preferred tool.

We actively discourage vigilantism.

You keep phrasing things in weird ways, but if I'm not mistaken, you and I are in agreement on this point: society is currently telling people that they shouldn't do anything when violence occurs, just sit back and let the police handle it.

At which point you bring up a whole lot of inconsistent research that manage to conclude something with a 312.5% margin of error and with extremely poor experimental design, and from a biased source to boot.

Dunno where you get that margin of error. Professor Kleck's book about his research led to him being awarded the Hindelang Award by the American Society of Criminology. I guess they thought his research was okay.

Did you know global warming is bunk, too? Exxon-Mobil published a study. There is no pollution from coal at all.

Still waiting for you to offer any sort of citation to support your propositions. By the way, I hate coal.

You're a retard.

Huh. I think you are not worth my time and this will be my last comment to you.

Perhaps, however, you misunderstood my comment. If a guy with a gun goes into a school or whatever and starts shooting the place up, all the people in that school are his victims IMHO. The ones he shoots are the worst off, of course, but everyone else can be said to be the victims of assault at minimum.

You ascribed a particular motive to the people who don't attack a school shooter: "Nobody stands up to put a stop to it, because they might get shot a few seconds earlier."

So, did I misunderstand you again? Were you not saying that the people who failed to attack the shooter were motivated out of a willingness to watch others die rather than increase their own personal risk?

I explained the role of society in deterrence, and you claim victim-blaming. I specifically said the victim has NO POWER over the situation, and it's the fault of everyone else in the world.

It's possible for "victims" to take a more active role in their own self-defense, and I'm in favor of that. It's also possible for bystanders to take a more active role in the defense of others, and I'm in favor of that too.

I'm less interested in blaming the bystanders for not acting, than in changing society to make it more likely that bystanders will act.

You claim I'm blaming Sally for getting raped by complaining that Tim, Bob, George, Amanda, Mark, Joseph, and Bill all stood by and did nothing. Are Tim, Bob, George, Amanda, Mark, Joseph, and Bill the victim?

Depends on the circumstances. If they watch some brute assault Sally with his bare hands and they do nothing, they aren't any kind of victims, and IMHO they should do something. If, however, the rapist has a buddy who his pointing a gun at all of them to cow them into inaction, then they are victims as well. I would actually prefer that they do something, rather than standing around; obviously the worst victim is Sally in this horrific scenario.

I'll say it again: if some guy with a gun crashes into a school and starts walking around shooting people, everyone in the school is a victim of the guy. Some of them are victims of gunshot wounds, others are victims of assault and being terrorized. It is unreasonable to declare that the average untrained person is making a cold, calculated decision to watch others die rather than put himself at risk; more likely he is frozen, deer-in-the-headlights, having trouble processing the situation and unsure what to do.

You extended too far with your bullshit art. You got burned.

Or, you misunderstood my point and then were very quick to call me a "retard" and so on.

Well, have a nice life.

Comment Re:When guns are outlawed (Score 1) 313

I consider myself a libertarian, but I am a minarchist and not an anarchist.

I view the proper role of government as enforcing the contracts that people freely enter into, plus defending people from actual harm.

I've read the Utopian visions of anarcho-captialism, where the free market solves all the problems, but I don't believe in it. How do you solve the "free rider problem" with respect to national defense? When someone is just insane and will not cooperate, how does voluntary arbitration resolve a dispute that person has with someone else?

If you want me to believe in the cooperative model of anarchy running as a smooth society, please give me an actual example from history where a country operated as an anarchy and it worked. (I can give you examples of minarchy that in my opinion worked.)

Comment Re:What idiocy (Score 1) 313

Victims are harmless, armed or not; you take them by surprise and you take them down. If they have weapons, you take them away before they can use them--this is hilariously easy when you attack someone and they turn out to have a firearm. A knife is actually more of a difficult proposition.

Citations, please. You have stated as fact that nobody ever successfully uses a firearm to prevent a violent attack, and that a knife is more likely to work for this purpose.

There is solid research estimating that firearms are used in the USA about two million times each year to prevent a violent crime. Most of these "defensive gun uses" do not involve anyone being killed or even anyone firing the gun; the defender deterred the assailant just by having a gun.


If you think a knife is a better defensive weapon, please read through this discussion.


A society of armed loners who only care about themselves is a society of targets.

You seem to be arguing that the average person is a sociopath who is willing to just watch others be hurt.

I suggest to you that a larger problem is that the majority of people have no idea how to handle a violent situation. The news media, and many of our celebrities, push a meme that ordinary people should never be armed for self-defense, and by extension shouldn't even train for self-defense. The same people who would like to ban all firearms in civilian hands would tell you that people shouldn't fight back against assailants; they should let the police handle the situation. (As the old saying goes, though, "When seconds count, the police are just minutes away!" There is no guarantee that the police will arrive in time to save lives.)

If a person is totally untrained, and suddenly face to face with horrible violence, it is unlikely that the person will swiftly and decisively come up with a plan to counter-attack and take out the assailant. I don't blame the victims the way you seem to, but I do wish more people would train in self-defense.

I agree with Larry Correia: our society would achieve a net reduction in violence if more people got trained in the use of weapons for defense, and more people carried concealed firearms.


P.S. I once, in an online discussion, commented that if people shouldn't defend themselves but rather should rely purely on the police to protect them, maybe people shouldn't have fire extinguishers in their homes and should rely purely on the fire department to protect them. A person I was debating agreed with this proposition. I didn't agree with her but I give her props for intellectual consistency.

Comment Tabbed terminal plus tmux (Score 1) 352

Once I started using GNOME 2.x I started using Gnome Terminal. I quickly grew to love having a terminal emulator with multiple tabs. I am still using it (well, now it's MATE Terminal) but I also use tmux to have multiple windows per tab.

Each tab is a different computer. Tab 1 is generally the local computer upon which I am working; then tabs 2 through whatever are the various remote machines. I ssh to the remote machine, then run tmux and open as many windows as I need.

tmux is essential so that I can pick up where I left off if anything interrupts my work... with SSH, if your Internet connection glitches, you lose your connection; with tmux you can re-attach to your previous session and continue your work right where you left off.

I have met someone who runs doubly-nested tmux sessions. He binds both Ctrl+A and Ctrl+B as prefixes, and he uses one of them to switch "outer" sessions (which are one per machine) and the other to switch nested terminal windows (multiple windows for working within a machine). I like having the separation of using Alt+1 through Alt+0 to switch machines and then Ctrl+A,1 through Ctrl+A,0 to switch windows on a particular machine. (Besides, I'm a vi user and I actually use Ctrl+B when editing.)

In a previous job I had to work on Windows a lot, so I used Console. I customized its hotkeys so that it works just like Gnome Terminal.


For a while I was daydreaming about a GUI terminal that can use the tmux protocol and have tmux features perfectly integrated into the terminal: use the GUI scrolling thumb to scroll within the tmux history buffer, etc. But these days I'm used to working within tmux and I don't really need the features to be part of the GUI terminal application.

A bonus of being used to the way tmux works: I can still do all the same things when logged in using JuiceSSH on my Android tablet. I buy Bluetooth keyboards that have the control key somewhere sensible so I can type commands and be productive.

Comment Re:This has been done before... (Score 1) 412

There is some sort of sign-up to book the theatre room in advance. And I think most people will have some sort of TV in their apartments, so they would have recourse if the theatre room was booked.

BTW the "hotel room" rooms aren't free; they have a nightly cost. I think the other shared resources are included and just need to be reserved ahead of time.

Comment Re:This has been done before... (Score 1) 412

It's not just any apartment complex. It's specifically designed to provide shared stuff for the benefit of the people staying there.

But I agree with you that it's not unprecedented. I visited a complex in the Capitol Hill neighborhood of Seattle, and it was much like this: small, efficient apartments plus shared amenities.

There is a very nice "home theatre" setup (not exactly home since it's shared in an apartment complex) that could seat about 16 people; a shared kitchen/dining space next to the theatre; on the roof, shared outdoor cooking grills; a yoga studio and space for art; and some kind of gym. There are "hotel room" units that residents can book for their guests. There are a few shared offices, used for people who work at home and sometimes need to meet with clients or consultants. There are storage spaces available for monthly rental, so people who have too much stuff for their small apartments can just walk down the hall to access the stored stuff. I think there is some kind of small clothes washer/dryer in the apartments but I wouldn't be surprised if there were a couple of large ones somewhere for shared use.

Overall I think it is a solid concept. If you want a huge TV screen once a week to watch a football game, you could use the theatre room and probably end up meeting everyone else in the complex who likes football. If you sometimes like to throw a party with lots of guests, again the theatre room with its attached kitchen is the place to do it. Your apartment doesn't need to be big enough to have guests overnight because you can book the "hotel rooms" ahead of time. In short, the apartments can be smaller because of all the shared stuff and it seems to work.

This was built years ago and I doubt it's unique. When I visited it I thought "there will be more like this in the future."

Comment Re:The elegant simplicity of slide rules (Score 1) 220

You need to remember that at the time Heinlein wrote that, computers did exist, but not general-purpose stored-program computers. Back then, computers were special-built things that had one purpose, like fire-control computers in the Navy; you couldn't make a fire-control computer do something else by swapping out a program.

All that said, you aren't wrong. Starman Jones is actually a bit clumsy; the computer works the way it's shown in the book because it has to work that way for the story to play out as Heinlein wanted it to. The idea of humans using pencil and paper to quickly compute the numbers to feed into the computer is silly; at a minimum there should have been another special-purpose computer device there to help them with the figuring.

P.S. I also enjoyed Beyond This Horizon where a computer expert in the far future wishes he could build a computer with 4-dimensional cams, since the three-dimensional ones weren't complex enough for the calculations he wanted to perform; and in Methuselah's Children (set in the 22nd Century) the protagonists steal a spaceship that had "one of the new computers with no moving parts".

Comment The elegant simplicity of slide rules (Score 3, Interesting) 220

What I find interesting is that it took a tremendously more advanced technology to render slide rules obsolete.

To make a slide rule, you need to figure out logarithms, then make exact marks on wood or something.

To make a modern calculator, you need to invent the microchip! You also need to invent a suitable display technology: light-emitting diodes or liquid crystal displays. We literally put a man on the moon before anyone was able to make a pocket calculator.

I love reading old science fiction stories set in the far future, where in the year 3423 or whatever people are still using slide rules. I imagine in the year 3423 people will still be using chairs, and probably spoons won't be too different... and back when those old stories were being written, slide rules seemed like that kind of basic item that wouldn't be going away.

P.S. Before the "pocket" calculator was invented, there were electronic desk calculators using Nixie tubes! Watch this video and think of how much labor it would be to assemble one of these. The soldering work alone guarantees that a typical college student could never afford one of these, but I'm sure NASA had calculators like this for engineers to use.


Comment Steam vapor cleaner (Score 1) 112

It seems to me like the best possible way to clean a space station would be to use a steam vapor cleaner. The environmental systems have to already be designed to deal with water vapor in the air, and the steam vapor cleaner uses no chemicals other than water, which would be recycled. A good steam vapor cleaner doesn't get things very wet... the steam is very hot.

I wonder whether they can afford the power to make steam... I don't know how much spare power they have from the solar power system. Maybe future space station designs could have a built-in steam cleaning system that uses solar power to directly heat the steam.

I bought a steam vapor cleaner, coincidentally because I wanted to use it to kill some mold. It worked perfectly for that purpose. I got a Vapamore MR-100 and I would buy it again.

Comment Re:Never again (Score 1) 190

I'm sticking with Apple devices from now on.

If you really want total control over your own devices, you can't beat Android. The trick is to choose a cell phone carrier that lets you own your own device.

I was a customer of Verizon for years and years, and I was happy with the quality of the cell phone service. I bought a Galaxy Nexus, happy that I would get updates (it's a Nexus device, right?).

Then I didn't get updates. Google released the updates, but Verizon didn't let them through. My Galaxy Nexus became so slow it was almost unusable, and I firmly believe that the Android 4.3 update (which added "TRIM" support) would have fixed my speed problems. All Galaxy Nexus users got the 4.3 update... except Verizon customers.

So I switched carriers. We are on T-mobile now and we have Nexus 5 phones. Overall, we are happy with T-mobile.

The Galaxy Nexus is past its end-of-life and Google isn't supporting it... but if I were to root it, I could put Cyanogenmod on it and get KitKat and the latest security patches. With the Nexus 5, I wouldn't even need to root it to use community-supported firmware builds; the devices aren't locked.

If you want total control of your own devices, Android devices plus a carrier that lets you buy your own devices is the way to go.

Samsung wants to sell me an $800 tablet

I love my Nexus 9 tablet. I got it, new, for about $365 and it is on my T-mobile cellular data plan, not just WiFi. And as it is a Nexus device it gets updates.

Comment IPython Notebook (Score 1) 325

I don't have a clear picture of what your organization will be doing, but your comment about "managing that data (=measurements + reports)" made me wonder if you will want to use the IPython notebook.


When people work to analyze measurements (make plots, etc. and make decisions) and then write new code, if they do so step by step in an IPython Notebook, and then other scientists can peer-review the notebooks, this might be even more useful to you than version control. It would give you a history of how the analysis was done and why the reports were made the way they were.

In my job, I do some analysis and work in databases, and I seriously want to start using IPython Notebook as my SQL client, and save my notebooks for later review. It would document the queries I ran and the results I got, so later I could find the queries again to re-run them, and see how they worked out before re-running them.


Comment Re:Are and storms that fierce on Mars? (Score 1) 124

You know, it occurs to me that you probably quit reading the novel at the worst possible place. You are so qualified to spot mistakes with chemistry and indoor gardening that you were repeatedly outraged and stopped a quarter of the way through. You missed on the later parts where the problems being solved had nothing to do with chemistry and indoor gardening.

I read an article where a couple of orbital dynamics guys said that Any Weir got the orbital dynamics stuff basically right; I've read multiple comments that said that the NASA politics stuff was believable; and in one of my favorite parts, Watney was stuck with a spacesuit whose helmet faceplate's glass had broken and he had to solve the problem of getting back to safety with a rather leaky spacesuit. There are other parts I don't want to mention because they are too spoilery.

You are probably too soured on the book to enjoy it, but if you ever try finishing it, I think you will find that the rest of the book offends you less than the first quarter of it did.

Comment Re:Are and storms that fierce on Mars? (Score 1) 124

Seriously, how can you read this tripe without wanting to hit your head against a wall? How can you call a novel that has this sort of nonsense and does almost every single chemistry equation wrong "hard science fiction"? Does anything that spouts pseudoscientific BS qualify as "hard science fiction" these days?

IMHO you are being too hard on the book. In the book, the things Watney does are plausible solutions to problems that make sense to me.

Andy Weir said he didn't want Watney being "hit by lightning" over and over. The initial chain of events that leads to Watney being stranded is implausible (and Andy Weir is the first to admit that the physics is wrong there, because the atmosphere of Mars is so thin). But once Watney is stranded, the rest of it makes sense to me.

This isn't like a story where someone needs to "restart the sun" by flying a ship made of "Unobtanium" into the sun and lighting off nuclear bombs. If you fix the science mistakes in a story like that, there is no story left; it's just fundamentally wrong.

In an interview, Andy Weir mentioned getting feedback from some chemist, and he said something like "I loved that, because chemistry is what I'm worst at". It sounds like you are so expert at the chemistry stuff that every mistake was a torment for you, and I think I get it... I can picture how annoyed I would be if the book was about software development, and lots of little stuff was constantly wrong.

One of his mistakes: someone actually calculated how much the Hab would heat up from burning up the rocket fuel to make water, and concluded that if Watney burned the fuel as fast as described, the Hab would heat up to 400 degrees C. But that mistake doesn't ruin the book for me, because we can assume that he just didn't burn the fuel as fast, or he arranged some sort of heatsink or something to get rid of the heat. Fundamentally, you can make water by burning hydrazine in the presence of oxygen, so it works for me.

I also liked the way he portrayed NASA. On the one hand, everything NASA does is expensive and takes forever, but on the other hand, his equipment works and he trusts it; and there was one launch that failed, and Weir listed two places where NASA procedures would have prevented the failure if there had been more time. (Someone would have studied the effects of a "shimmy" on protein cubes, and also someone would have found a minor defect in a bolt and replaced it with a perfect one; either of these would have prevented the failure.)

A novel that I hated, that I just couldn't get through, is The Windup Girl. I bought it figuring "anything that wins both the Hugo and the Nebula must be worth reading" but I hated it. I couldn't swallow the science upon which the whole plot rests. It's the future, and the worst predictions of catastrophic anthropogenic global warming came to pass: the sea levels have risen, temperatures are high, lots of people died off. As a result, fossil fuels are no longer used by anyone, and the world is in a horrible depression. So, you might think that nuclear power, solar power, and Internet telecommuting would be a big deal? Nope, cities are lighted with methane gas lamps, and the methane is made from animal feces, and moving things are powered by kinetic energy stored in "kink-springs" and the springs are wound by elephant-sized bioengineered animals. No buildings seem to have solar panels on them, and at one point the protagonist uses a computer powered by a treadle! The Internet barely seems important, which is hard to believe given that the Internet is already hugely important... but in this future catastrophe world it now takes months for a business executive to travel from America to Thailand (he has to travel by wind-powered ship), yet they still send the executive instead of using teleconferencing.

I hated The Windup Girl as much as you seem to have hated The Martian. So I guess I understand how you feel about The Martian, but I don't feel the same way.

I think the difference for me is that The Windup Girl feels like the author worked backward from his desired goals: "biopunk" is cool, so let's explain why everything is biopunk now; I want to have big factories full of elepant-sized animals walking in circles to wind "kink-springs". Whereas The Martian feels like one situation flows to another. And in fact in an interview he said that this is how he wrote the book: after he had Watney do something, he thought about what would likely happen next, and worked from there.

P.S. In the book, Watney joked about poking a hole in his glove and flying around in space like Iron Man, and they discussed just how stupid and unworkable that idea was... even Watney didn't think it would work. I gather that the movie changed this part quite a bit.

ASHes to ASHes, DOS to DOS.