Only in a few limited cases. Last year, my wife and I finally decided to terminate our land-line phone. It was only used by telemarketers, and everyone else used our cell phones, so why keep paying for it? We both also use Skype; her company uses it routinely for the growing portion of employees that are working at home part of the time. At the time, I also had a SIP phone as part of a job I was working on.
Anyway, we did a bunch of checking, and found that we couldn't transfer the land-line number to any of our other "phone" services. The number is owned by the local monopoly (Verizon), and they won't even talk to you about transferring numbers anywhere but to another land-line phone, which they only allow because the FCC says they have to. If we wanted to keep the number, we had to keep paying for it as part of a land-line contract, and we couldn't make it mobile by forwarding it to another non-land-line number.
A year later, we're still discovering cases where someone has cached our old number and had tried to use it for the first time in years. The most recent was last month, when a doctor's office tried to call us to say the doctor was home sick (;-) and they wanted to reschedule an appointment for a checkup. I'd called them a few days earlier, but nobody had noticed that their database had a different number that I was using. So I drove the 10 miles, only to tell them my cell number and reschedule, then drove back home.
It would have been useful for cases like this to have the old number redirect to one of our cell phones, or to the Skype accounts that we both have. But this is the US; the phone companies don't have to do such things unless the FCC tells them they have to. And the FCC is run by people who think that "phone" means the old wired, single-use, voice-only comm gadgets.
An even older example of perpetual copyright is that until the Protestant Reformation ended the Catholic religious monopoly in Europe, it was almost universally illegal (and sometimes punishable by death) for anyone to publish or distribute bibles without church permission.
One of the things that got European leaders upset with the first Mongol exploratory expedition (circa 1220) was that they brought along a company of Korean printers, who printed and sold Korans and Bibles as they travelled. The motive was mostly to help the expedition to pay for itself. The Mongols had learned that the West didn't have very good printing technology, and the religious texts weren't generally available to most of the population. They thought that cheap religious texts would be good sellers, which was quite true. But they didn't anticipate the rage this would induce in the Western rulers, whose control over the population was partly built on keeping people illiterate and ignorant. The attacks that the Mongol expedition had to fight off were in part an attempt to stop this "copyright infringement". There was also widespread propaganda saying that the Mongols were in league with the devil, as an attempt to dissuade people from doing business with the "invaders".
This did sorta backfire, though. Subsequent Mongol expeditions, in the 1230s and later, were in response to the reports that Ghenghis and crew delivered, describing the west as ignorant, illiterate, warlike barbarians who were a potential threat to the civilized world. So they organized a military force that attempted to "pacify" the far west and introduce modern innovations like education, literacy and commerce. This had only limited success, as is usual with such military "solutions" to social problems. But it did limit the range of western military operations for a few centuries. Then, of course, in the 15th century, westerners developed cheap printing operations, and copyright became an internal battle within Europe.
Copyright has always been about maximizing publishers' and distributors' income by limiting the access of the general population to information. But at least today, copyright infringement isn't punishable by death without trial.;-)
Whether it's easy is another matter (I would argue "Yes: Stop being a panzy";) ).
Is a panzy someone who drives a Panzer?;-)
Anyway, I found it sorta fun to argue on that side of the issue, since my usual "devil's advocate" approach is to argue in favor of C, which provides no checking of anything, but supplies the low-level bit/byte access that lets me easily program my own checking. That way, my code doesn't need to check data that is provably within range. This makes the code faster than in most other languages, which check (almost) everything whether it's logically necessary or not.
Thus, if x's value just came from x = y & 0xF, and the array z has a size > 16, it's not necessary to check z[x]. In a language that always checks array indexes, this is a waste of CPU cycles.
Of course, C is notoriously a bad idea for programmers without the sense to implement lots of sanity checks. These also help to document the assumptions that earlier programmers made about the data, something that few programmers ever bother to document clearly. So someone tweaking or retargeting my C code years later doesn't unknowingly call a routine with out-of-range args, because the routine generates error messages. (So the programmer goes into the routine and deletes the range check;-).
But it's easy to see the other side of the issue. And I have worked on machines that did array bounds checking in hardware, with no time cost (just a bit of extra cpu circuitry). It's disappointing that we've known for decades what a good idea this can be, but the people in charge of purchase decisions have decided that they don't want it. So we get lots of malware that takes advantage of out-of-bounds array references in commercial software written by programmers working under marketing-driven time schedules.
In any case, it's always fun to try to find ways to argue both sides of an issue.
(And I'm a bit bemused by the fact that my post got an "overrated" mod, when it hasn't been rated at all by anyone.;-)
Even a simple ADD instruction will give the wrong result when the hardware fails.
True, but the reality is much worse than that. A simple ADD instruction will also give a wrong result, on all current "popular" CPUs, when the hardware is working exactly as designed.
To the people who design CPUs, adding two positive integers and getting a negative result is exactly what the hardware should do in some cases, depending on the values of the integers. This wreaks havoc with software designs that assume the mathematical definition of integer addition.
Yes, I know that the hardware also sets an overflow flag bit somewhere to indicate that the result isn't (mathematically) correct. But the implementations of most programming languages, including all the common ones, knowingly and intentionally hides the overflow flag from the software. If you pick up a few of the top-selling programming-language texts, and look through the index for information on how the language handles things like integer overflows, you typically won't find any mention of it. The people working at "higher" levels can't be bothered with such mundane details.
They get away with all this because the people paying money for the computer systems and the software aren't generally willing to pay for hardware or software that always produces correct results. Programmers who insist on such correctness tend to find themselves shuffled off to the side or laid off, in favor of programmers who can write software to management's release schedules.
This is all hardly a secret. People have learned that you don't have to be secretive about how crappy most software (or hardware) is, because the people in positions to control purchasing don't read the technical literature and don't particularly care about such geeky stuff as overflow bits. So we can talk about it all we like amongst ourselves; it makes no difference to the people signing the purchase orders and paying our salaries.
you can download the instruction from the Pirate Bay...
Just wait a few weeks; you might be right...
My immediate thought was related: The US government probably does have the info hidden away in some obscure department's archives, hidden behind a wall of secrecy and classification. The repair guys just don't have the right clearances, and instead of saying "We can't give you that information", the agency says "We don't have that information".
It could also be a case of Clarke's third law. The information is stored away somewhere, but the repair crews don't know the name of the archive or who runs it, and the people at the archive haven't heard that anyone's looking for it. And chances are that if you ask for the info using the part's name, they won't be able to find it; you have to tell them the code number (or whatever they call it) for that particular part.
That is, the information could be hidden by ignorance and incompetence, not by any active efforts to hide or eliminate the information. That happens all the time any large organization, businesses as well as governments.
Actually, my other thought was "Did they google it?" Chances are that google could tell them the part number(s), and maybe also the torrent name at the Pirate Bay.
Heh. You missed the point of my suggestion. I was wondering whether one could make a living collecting public information about the US (and other) military, and selling it to other governments. Of course, you can do that for one government spy agency (and sometimes two;-). But could you do it as an open, commercial operation, selling the information to all interested governments?
The fact that that earlier study resulted in the report being classified implies that in the US, if the researchers had tried selling it to other governments, they'd have been arrested and sent to a federal prison. The fact that the information was all from public data sources would be considered irrelevant; the summary was still classified and selling it to another government would be a criminal offense.
I'd bet that this sort of extreme illogic isn't anything at all unique to the US government.
And who in their right mind thinks that a foreign nation doesn't already know the existence, location and layout of various bases around the world?
It reminds me of the story (reported in various tech journals but not so much in the MSM) back in the 1970s about the US DoD funding a study by some university people of what could be learned about US military sites and activity from public sources like newspapers, libraries, etc. The story was that a couple of profs (i.e., their grad students) spent a year perusing such public information sources, wrote up their report, sent it in - and with a few days, it was classified Top Secret.
When I read that, I did wonder how many offers of employment the profs (and their grad students) got from various foreign governments. It seemed to me that it could become a viable career path for a small number of people. But I never read any followups.
Now I wonder how much you could learn by just googling for the information. And if you sent your summary report to the DoD, how quickly would it get classified?
Ki>Zero. The bane of all. It was the gateway math to all modern problems. It would be so much simpler with just countables.... Whoever it was who invented zero should take responsibility for all the worlds problems, ex nehilo.
Heh. I'm glad someone managed to bring up what should be obvious to anyone competent in basic math. While reading the posts here, I kept thinking "Yeah, and you have the same sort of problems if you allow your numbers to include zero." But I figured that the folks making the silly arguments probably wouldn't understand that sort of verbal irony, so I just let it pass.
I can easily imagine variants of most of the arguments here being used thousands of years ago against the individuals in India and Central America that started casually using that weird "0" symbol in their calculations. "What's the need for something that doesn't represent anything?" "I only need to count things that exist; there's no reason to count things that don't exist." And on and on.
This whole discussion does sorta put a limit to any claims of technical competency on the part of the "tech nerd" population of/.
(And to I need an extra . at the end of that sentence? That oughta be good for a long discussion, as well as the question of whether or not the final ')' in this sentence balances the initial '('.;-)
I recently discovered a horrible lapse of auditing in our program where user_id's were set = "".
As late as the mid-1990s, there was a common bug in many unix systems, in which an entry in/etc/passwd with null fields was considered valid. And even better, a blank line would often be treated as an entry with all its fields blank. A null numeric field such as uid and gid would be treated as zero. This meant that if the password file contained a blank line, you could become super-user by typing all of 6 chars (counting the newline):
su ""
The null user name would match the first field in the blank line, the numeric uid was zero, and you were in.
I learned about this in my first intro to unix, in 1981. I was duly impressed when I found the bug still alive in the systems used where I worked as a contractor in 1994. In a meeting one day, the group's manager asked if my debugging would be made easier if they told me the root password to the lab's test machines. I said that it wouldn't help, because if I needed root access, I just made my own root account, which was desirable because that way the accounting would keep my root use separate from other super-users, so we could tell which super-user had done what. All the lab machines had a blank line in the password file between the "system" and "user" accounts.
But eventually they wanted to know how I made my own super-user accounts. Testing became more difficult after that, since their security people didn't understand why machines in the test lab should be so easily available to the people paid to use them for testing, and kept hiding the passwords from the people who needed them to do their job.
It's also sorta fun to see how confused people can be about "null" values...
Of course there is more than a syntatic difference between a reference and a pointer in C++. For one, references CANNOT be null, while pointers are allowed to be null.
This reminds me of an embedded project that I worked on some years ago, that was mostly coded in C. For reasons having to do with the CPU and its hardware memory mapping, we found it handy to have a global variable declared as "extern unsigned char* physmem;", whose address was defined during linking to be zero. I was duly impressed by the fact that the C compiler wasn't fazed by this, and handled it correctly. I.e., the value of &physmem was numerically zero, the same as a null pointer. This allowed us to use physical memory as "just a byte array", and eliminated the need for clumsy special-purpose code for dealing with this one special byte array.
If it's true that C++ doesn't allow this, then that excludes the use of C++ on hardware with such properties. Of course, people working at the level that we were generally wouldn't take you seriously if you suggested C++. We had enough trouble convincing some of them that the work should be done in C rather than assembly language ("as God intended", where "God" was the name of the committed that designed the hardware;-). If C had imposed such silly restrictions, the job probably would have been done in assembly.
Nobody's sure exactly what Innovation(tm) is, but we know it's heavily dependent on Intellectual Property(c) and it's vitally important that Intellectual Property(c) be Protected(r).
Actually, it's fairly easy (now that we have google as a research aid) to make a sampling of the use of the word "innovation" and determine its meaning:
innovation (n.): Making small, mostly cosmetic changes to someone else's product, then marketing it as an important new development, while suing the producers of the earlier product for infringing on your Intellectual Property in an attempt to bankrupt them with your larger legal budget.
The term is occasionally found with other meanings, but this is the primary definition that will help readers understand most of the uses they'll find today.
Hmmm... This could be taken as an example of what's so screwed up with the computer "market". To make the canonical automotive comparison: If a new make of auto were to capture 8% of the market in just a few weeks, it would be considered one of the most successful product introductions in the history of the industry. If you're anywhere in the "developed" world, try watching any busy stretch of road for a while, and try to spot a car model that makes up even 1% of the traffic.
But in the computer biz, 8% is called "tiny". If your product isn't the market leader and controlling 90% of the market, you aren't worth mentioning (and thus most of your potential customers don't know you exist). Try telling a BMW or Acura owner that their car isn't significant, because it's under 1% of auto sales. But computer people make such comments in all seriousness.
It seems that most of the posts here have totally missed the point. The question wasn't about free software, where the "zero price" definition of free is meant. The question was about OSS, i.e., Open Source Software. This means software whose source code is open and available for examination. And in the schools, the justification should be obvious. Just utter the canonical "Think of the children" mantra.
The reason one wants open-source software is that you want to be able to examine the software to make sure that it really does what it's advertised to do, and nothing else. If your software is closed-source, it can (and probably does) have a number of unadvertised "features" that you can't know about. You should ask yourself "Why doesn't the vendor want us to know about those additional features of the software.
And we have lots of experience with answering this question. It's fairly common for proprietary, binary-only software to collect information about its use and report them back to the vendor. In the case of proprietary educational software, this means that data about your child's behavior is being collected and sent to a remote database that you have no access to.
Closed-source software should be automatically considered a tool for collecting data about the users. So you should be asking the school admins "Do we want to allow software that collects data about our children, and keeps it hidden from us?" Explain to them that unless the software is open-source, they have no defense against such data collection. Only open-source software is available for examination to determine what it's really doing.
Get people thinking this way, and you can probably get them out chasing after the closed-source suporters with pitchforks.
(If you succeed, try to get videos. A lot of us would like to watch the fun.;-)
If the mass isn't accelerating, there is no force.... Much more at Wikipedia for Force.
Well, again, I was curious about this interpretation of the physics, so I took the extreme step of actually reading the article. Even a cursory glance at the first paragraph shows that it doesn't agree at all.
To make it clear, the claim seems to be that if you and I are pushing on opposite sides of an object and it doesn't move, we are exerting no force. This is clearly a possible interpretation of the physics, and there's something that is zero in this scenario. But I don't think it agrees with the definition of "force" that physicists or engineers use.
Thus, the WP article says "In physics, a force is that which can cause an object with mass to change its velocity." Note that little weasel word "can". This statement is consistent with the interpretation that two (non-zero) forces might cancel each other, resulting in no change of velocity. Acceleration isn't required for there to be forces on an object. Actually, it's the other way around; an acceleration shows that there's a (net) force being applied to the object. But forces may be present without a resulting acceleration, if the sum of the force vectors is zero. I am being accelerated by the Earth's mass, but it's ineffectual, because there's a counteracting force, the electrostatic charges in the atoms of the thing that I'm sitting on. Actually, it's not totally ineffectual, because I contain pressure sensors that measure the counteracting force, and those sensors are sending a nonzero signal to my central nervous system.
The WP article reinforces this interpretation with a later statement: "Newton's second law states that an object with a constant mass will accelerate in proportion to the net force acting upon and in inverse proportion to its mass." Note again that it refers to "the net force", not "the force". This is tacit acknowledgement that there may be multiple forces at work, and the acceleration is due to the sum of the applied forces. If that sum is zero, there is no acceleration, but those forces still exist.
I think you're using "force" as a shorthand for what the WP article (and most physicists and engineers) call "net force" or "the sum of all forces" or some such more elaborate phrase.
Maybe we need an explicit term for this concept, so that people don't continue to confuse it with the concept of "force". This term would refer to something that does disappear when all the applied forces sum to zero. But it shouldn't be called "force", because that's already in use for a slightly different concept.
Hmmm... I've seen a number of comments like that, and I was curious. I'm sitting in a rather strong (gravitational) field that seems to be totally static. Yet I can feel its push, by the pressure my bottom surfaces feel from the chair I'm sitting in, even when I'm not moving. If I hold an object out to the side and release it, it falls to the floor every time. The energy required to produce that motion has to come from somewhere, and the gravitational field seems the only likely source.
Only when something moves perpendicular to the field is energy transferred.
So the energy to the things I've dropped came from my moving them perpendicular to the vertical gravitational field, i.e., when I moved them horizontally? I can easily test this. I picked up one of the objects, carefully lifting it with a vertical motion, and released it. It fell to the floor. So it picked up energy while being moved parallel to the field. The falling speed doesn't seem to vary depending on how I move an object into position before dropping it.
Meanwhile, I made some similar tests with a convenient magnet (taken from the refrigerator door). It seems that the magnet attracts small metallic objects from any direction, no matter how they were moved there relative to the magnetic field. The field is obviously static. So how would you explain this motion, which seems the same regardless of how I move the small objects relative to the magnet?
Maybe the physics of static gravitational and magnetic fields are different in my living room from where you are in the universe...
Since all of their little film-cells rotate in the same direction, this says to me that there is an unaccounted-for field which is breaking the symmetry and starting the effect.
Huh? In that video that's linked to, the film begins with a visible counter-clockwise rotation, and after a few seconds, it visibly halts. Then it begin again with a clockwise rotation. This seems to be initiated by some motion along the top edge of the cell.
So what are you seeing that's different from what's running on my screen?
The URL for the video I'm looking at is "http://softmatter.cscm.ir/FilmMotor/movies/movie.1.wmv". Do others see the rotation differently than I do? On my screen, in a firefox 3.0.6 window, the change in rotation direction seems very obvious to my eyes.
The government is democratically elected. It is not a free democracy however because all candidates have to be approved by the ulama....
Hmmm... If you substitute "the two major political parties" for "the ulama", it sound very much like the US. Some other democracies have three major parties, but people are often pointing out that the number doesn't really matter. What matters is that a small unelected oligarchy controls who can run for office.
So maybe this is an inherent part of human societies. What's the chance that we can ever do anything that works better? Just changing the name that the media uses for the oligarchy doesn't seem to much affect the outcome.
Hmm... a "troll" rating and a serious reply. And I even kept the "Good Joke" title. Maybe I should remind myself that/. is full of the humor-impaired who don't recognize intended humor without a;-).
Law or no law, if my router doesn't capture it I am not capturing it. I don't know how to do it, nor will I pay someone to do it.
Actually, I'd sorta like to know how to do this. We've had a couple of wifi gadgets in our house, and none seems to have any (documented) way to collect such data. Right now we have an Apple Airport. I've asked around a bit, googled, etc, but I haven't found any way to make it tell any of our computers who's connected or how much data they're sending. I'd like to be able to monitor this myself, but if it's possible, Apple isn't telling. Or maybe they would, if I knew the right magic words to ask about.
In general, this could be useful information for people using wifi. We probably won't get it without some way of pressuring the vendors to tell us how it works, which is probably different for every one of them.
(Yes, I know about SNMP. I've implemented SNMP agents and clients. I know where the info should be in the MIB. I also know how vendors can make SNMP quite incompatible if they want to; I've worked on projects where management ordered us to do that. The Airport has those four letters in its config stuff, but I've never got it to respond to a query from a client. Similarly for other brands. If I can't make it work, I can't imagine that your typical home user would have any chance at all.;-)
[U]nless if they are continually pushed to a secure location you could alter them the second that you receive a notice from law enforcement to provide them with logs.
Well, there's an obvious solution to that. Just require that all log data be instantly transmitted to a government repository for archiving. This would also eliminate the need for home wifi users to purchase expensive storage devices to hold the logs. Instead, we'd just have a government agency with funding to buy a few terabytes of disk space per day to store all the logs.
Think of the economic stimulus from the huge purchases of storage devices by this agency...
Sometimes it takes more than being careful; you also have to understand how some of the crazy browsers can screw things up.
I learned this some years ago, when I first found/. and did a bit of moderation. I've always liked that way that most (but not all) browsers will scroll down about.95 pages if you tap the space bar. But I found that this didn't always work. With/., sometimes hitting the space bar worked, and sometimes it seemed to do nothing. I'd hit Space a few times, mutter "WTF???", reach for the mouse, move to the scroll bar, and do it that way.
It was quite a few incididents like this before I finally discovered what was happening. It turned out that, if I had used a menu for moderation, after that the browser would interpret a space as meaning to scroll the menu down one item. This can be hard to spot, because of course your eye is aimed at the bottom of the screen, not at the menu that's up higher.
When I discovered what the browser was doing to me (or to the author of the post that I'd now mis-moderated), I was of course duly shamed, but there was nothing I knew to do about it. It took me some time to learn about undoing moderations by posting.
So being careful isn't enough. If you don't understand such obscure misbehaviors of your browser, you'll just very carefully do the wrong thing. And if the change is small enough to not attract your eye, you won't understand what was done; you'll just think that the damn browser has just forgotten how to scroll.
It's just one of many ways that the current GUIs in general (and the flock of browsers in particular) is user-hostile in so many little ways. Telling users to be CAREFUL doesn't do it. We should find a way to fix such things that seem designed to trick users into doing the wrong thing.
[c]an you provide citations that Wikipedia's aggregate quality has improved?
Certainly. I found several of them by just reading this discussion. And a quick scan of the messages below this one shows several more. And there have been many other/. discussions with similar citable claims. But don't use the/. search thingy; it ain't worth a damn. Use google.;-)
I got "Funny", "Informative" and "Flamebait" mods for this one. (And the "Overrated" mod seems to have disappeared.)
This rating has surpassed all my previous ratings for incongruity. I'll have to keep a link to it, as a nice example of how screwy the moderation can get around here.
It is impressive how poor a sense of humor a lot of the folks here seem to have. Maybe I should have included a smiled. But I really thought it would be redundant this time.
Yeah; I was a bit surprised by that "+5 Informative" rating. But I clicked on it and got the details. Only one mod was "Informative". Another was "Funny", which was what I was going for. The other was "Underrated", which has me a bit puzzled.
And I well remember when I was little, and was sent to Sunday School at several different churches as we moved around every few years. In every one of them, I heard "teaching" that if you truly believe in God, and pray to Him (and tithe;-), you'll get very rich. Lots of other religious people have, so you can, too.
Slashdot Mirror
In the US, we have number portability.
Only in a few limited cases. Last year, my wife and I finally decided to terminate our land-line phone. It was only used by telemarketers, and everyone else used our cell phones, so why keep paying for it? We both also use Skype; her company uses it routinely for the growing portion of employees that are working at home part of the time. At the time, I also had a SIP phone as part of a job I was working on.
Anyway, we did a bunch of checking, and found that we couldn't transfer the land-line number to any of our other "phone" services. The number is owned by the local monopoly (Verizon), and they won't even talk to you about transferring numbers anywhere but to another land-line phone, which they only allow because the FCC says they have to. If we wanted to keep the number, we had to keep paying for it as part of a land-line contract, and we couldn't make it mobile by forwarding it to another non-land-line number.
A year later, we're still discovering cases where someone has cached our old number and had tried to use it for the first time in years. The most recent was last month, when a doctor's office tried to call us to say the doctor was home sick (;-) and they wanted to reschedule an appointment for a checkup. I'd called them a few days earlier, but nobody had noticed that their database had a different number that I was using. So I drove the 10 miles, only to tell them my cell number and reschedule, then drove back home.
It would have been useful for cases like this to have the old number redirect to one of our cell phones, or to the Skype accounts that we both have. But this is the US; the phone companies don't have to do such things unless the FCC tells them they have to. And the FCC is run by people who think that "phone" means the old wired, single-use, voice-only comm gadgets.
An even older example of perpetual copyright is that until the Protestant Reformation ended the Catholic religious monopoly in Europe, it was almost universally illegal (and sometimes punishable by death) for anyone to publish or distribute bibles without church permission.
One of the things that got European leaders upset with the first Mongol exploratory expedition (circa 1220) was that they brought along a company of Korean printers, who printed and sold Korans and Bibles as they travelled. The motive was mostly to help the expedition to pay for itself. The Mongols had learned that the West didn't have very good printing technology, and the religious texts weren't generally available to most of the population. They thought that cheap religious texts would be good sellers, which was quite true. But they didn't anticipate the rage this would induce in the Western rulers, whose control over the population was partly built on keeping people illiterate and ignorant. The attacks that the Mongol expedition had to fight off were in part an attempt to stop this "copyright infringement". There was also widespread propaganda saying that the Mongols were in league with the devil, as an attempt to dissuade people from doing business with the "invaders".
This did sorta backfire, though. Subsequent Mongol expeditions, in the 1230s and later, were in response to the reports that Ghenghis and crew delivered, describing the west as ignorant, illiterate, warlike barbarians who were a potential threat to the civilized world. So they organized a military force that attempted to "pacify" the far west and introduce modern innovations like education, literacy and commerce. This had only limited success, as is usual with such military "solutions" to social problems. But it did limit the range of western military operations for a few centuries. Then, of course, in the 15th century, westerners developed cheap printing operations, and copyright became an internal battle within Europe.
Copyright has always been about maximizing publishers' and distributors' income by limiting the access of the general population to information. But at least today, copyright infringement isn't punishable by death without trial. ;-)
Whether it's easy is another matter (I would argue "Yes: Stop being a panzy" ;) ).
Is a panzy someone who drives a Panzer? ;-)
Anyway, I found it sorta fun to argue on that side of the issue, since my usual "devil's advocate" approach is to argue in favor of C, which provides no checking of anything, but supplies the low-level bit/byte access that lets me easily program my own checking. That way, my code doesn't need to check data that is provably within range. This makes the code faster than in most other languages, which check (almost) everything whether it's logically necessary or not.
Thus, if x's value just came from x = y & 0xF, and the array z has a size > 16, it's not necessary to check z[x]. In a language that always checks array indexes, this is a waste of CPU cycles.
Of course, C is notoriously a bad idea for programmers without the sense to implement lots of sanity checks. These also help to document the assumptions that earlier programmers made about the data, something that few programmers ever bother to document clearly. So someone tweaking or retargeting my C code years later doesn't unknowingly call a routine with out-of-range args, because the routine generates error messages. (So the programmer goes into the routine and deletes the range check ;-).
But it's easy to see the other side of the issue. And I have worked on machines that did array bounds checking in hardware, with no time cost (just a bit of extra cpu circuitry). It's disappointing that we've known for decades what a good idea this can be, but the people in charge of purchase decisions have decided that they don't want it. So we get lots of malware that takes advantage of out-of-bounds array references in commercial software written by programmers working under marketing-driven time schedules.
In any case, it's always fun to try to find ways to argue both sides of an issue.
(And I'm a bit bemused by the fact that my post got an "overrated" mod, when it hasn't been rated at all by anyone. ;-)
Even a simple ADD instruction will give the wrong result when the hardware fails.
True, but the reality is much worse than that. A simple ADD instruction will also give a wrong result, on all current "popular" CPUs, when the hardware is working exactly as designed.
To the people who design CPUs, adding two positive integers and getting a negative result is exactly what the hardware should do in some cases, depending on the values of the integers. This wreaks havoc with software designs that assume the mathematical definition of integer addition.
Yes, I know that the hardware also sets an overflow flag bit somewhere to indicate that the result isn't (mathematically) correct. But the implementations of most programming languages, including all the common ones, knowingly and intentionally hides the overflow flag from the software. If you pick up a few of the top-selling programming-language texts, and look through the index for information on how the language handles things like integer overflows, you typically won't find any mention of it. The people working at "higher" levels can't be bothered with such mundane details.
They get away with all this because the people paying money for the computer systems and the software aren't generally willing to pay for hardware or software that always produces correct results. Programmers who insist on such correctness tend to find themselves shuffled off to the side or laid off, in favor of programmers who can write software to management's release schedules.
This is all hardly a secret. People have learned that you don't have to be secretive about how crappy most software (or hardware) is, because the people in positions to control purchasing don't read the technical literature and don't particularly care about such geeky stuff as overflow bits. So we can talk about it all we like amongst ourselves; it makes no difference to the people signing the purchase orders and paying our salaries.
you can download the instruction from the Pirate Bay...
Just wait a few weeks; you might be right ...
My immediate thought was related: The US government probably does have the info hidden away in some obscure department's archives, hidden behind a wall of secrecy and classification. The repair guys just don't have the right clearances, and instead of saying "We can't give you that information", the agency says "We don't have that information".
It could also be a case of Clarke's third law. The information is stored away somewhere, but the repair crews don't know the name of the archive or who runs it, and the people at the archive haven't heard that anyone's looking for it. And chances are that if you ask for the info using the part's name, they won't be able to find it; you have to tell them the code number (or whatever they call it) for that particular part.
That is, the information could be hidden by ignorance and incompetence, not by any active efforts to hide or eliminate the information. That happens all the time any large organization, businesses as well as governments.
Actually, my other thought was "Did they google it?" Chances are that google could tell them the part number(s), and maybe also the torrent name at the Pirate Bay.
You can, indeed, make a career of such activities:
https://www.cia.gov/careers/jobs/view-all-jobs/open-source-officer-foreign-media-analyst.html
Heh. You missed the point of my suggestion. I was wondering whether one could make a living collecting public information about the US (and other) military, and selling it to other governments. Of course, you can do that for one government spy agency (and sometimes two ;-). But could you do it as an open, commercial operation, selling the information to all interested governments?
The fact that that earlier study resulted in the report being classified implies that in the US, if the researchers had tried selling it to other governments, they'd have been arrested and sent to a federal prison. The fact that the information was all from public data sources would be considered irrelevant; the summary was still classified and selling it to another government would be a criminal offense.
I'd bet that this sort of extreme illogic isn't anything at all unique to the US government.
And who in their right mind thinks that a foreign nation doesn't already know the existence, location and layout of various bases around the world?
It reminds me of the story (reported in various tech journals but not so much in the MSM) back in the 1970s about the US DoD funding a study by some university people of what could be learned about US military sites and activity from public sources like newspapers, libraries, etc. The story was that a couple of profs (i.e., their grad students) spent a year perusing such public information sources, wrote up their report, sent it in - and with a few days, it was classified Top Secret.
When I read that, I did wonder how many offers of employment the profs (and their grad students) got from various foreign governments. It seemed to me that it could become a viable career path for a small number of people. But I never read any followups.
Now I wonder how much you could learn by just googling for the information. And if you sent your summary report to the DoD, how quickly would it get classified?
Ki>Zero. The bane of all. It was the gateway math to all modern problems. It would be so much simpler with just countables. ... Whoever it was who invented zero should take responsibility for all the worlds problems, ex nehilo.
Heh. I'm glad someone managed to bring up what should be obvious to anyone competent in basic math. While reading the posts here, I kept thinking "Yeah, and you have the same sort of problems if you allow your numbers to include zero." But I figured that the folks making the silly arguments probably wouldn't understand that sort of verbal irony, so I just let it pass.
I can easily imagine variants of most of the arguments here being used thousands of years ago against the individuals in India and Central America that started casually using that weird "0" symbol in their calculations. "What's the need for something that doesn't represent anything?" "I only need to count things that exist; there's no reason to count things that don't exist." And on and on.
This whole discussion does sorta put a limit to any claims of technical competency on the part of the "tech nerd" population of /.
(And to I need an extra . at the end of that sentence? That oughta be good for a long discussion, as well as the question of whether or not the final ')' in this sentence balances the initial '('. ;-)
I recently discovered a horrible lapse of auditing in our program where user_id's were set = "".
As late as the mid-1990s, there was a common bug in many unix systems, in which an entry in /etc/passwd with null fields was considered valid. And even better, a blank line would often be treated as an entry with all its fields blank. A null numeric field such as uid and gid would be treated as zero. This meant that if the password file contained a blank line, you could become super-user by typing all of 6 chars (counting the newline):
su ""
The null user name would match the first field in the blank line, the numeric uid was zero, and you were in.
I learned about this in my first intro to unix, in 1981. I was duly impressed when I found the bug still alive in the systems used where I worked as a contractor in 1994. In a meeting one day, the group's manager asked if my debugging would be made easier if they told me the root password to the lab's test machines. I said that it wouldn't help, because if I needed root access, I just made my own root account, which was desirable because that way the accounting would keep my root use separate from other super-users, so we could tell which super-user had done what. All the lab machines had a blank line in the password file between the "system" and "user" accounts.
But eventually they wanted to know how I made my own super-user accounts. Testing became more difficult after that, since their security people didn't understand why machines in the test lab should be so easily available to the people paid to use them for testing, and kept hiding the passwords from the people who needed them to do their job.
It's also sorta fun to see how confused people can be about "null" values ...
Of course there is more than a syntatic difference between a reference and a pointer in C++.
For one, references CANNOT be null, while pointers are allowed to be null.
This reminds me of an embedded project that I worked on some years ago, that was mostly coded in C. For reasons having to do with the CPU and its hardware memory mapping, we found it handy to have a global variable declared as "extern unsigned char* physmem;", whose address was defined during linking to be zero. I was duly impressed by the fact that the C compiler wasn't fazed by this, and handled it correctly. I.e., the value of &physmem was numerically zero, the same as a null pointer. This allowed us to use physical memory as "just a byte array", and eliminated the need for clumsy special-purpose code for dealing with this one special byte array.
If it's true that C++ doesn't allow this, then that excludes the use of C++ on hardware with such properties. Of course, people working at the level that we were generally wouldn't take you seriously if you suggested C++. We had enough trouble convincing some of them that the work should be done in C rather than assembly language ("as God intended", where "God" was the name of the committed that designed the hardware ;-). If C had imposed such silly restrictions, the job probably would have been done in assembly.
Nobody's sure exactly what Innovation(tm) is, but we know it's heavily dependent on Intellectual Property(c) and it's vitally important that Intellectual Property(c) be Protected(r).
Actually, it's fairly easy (now that we have google as a research aid) to make a sampling of the use of the word "innovation" and determine its meaning:
innovation (n.): Making small, mostly cosmetic changes to someone else's product, then marketing it as an important new development, while suing the producers of the earlier product for infringing on your Intellectual Property in an attempt to bankrupt them with your larger legal budget.
The term is occasionally found with other meanings, but this is the primary definition that will help readers understand most of the uses they'll find today.
How many people are using Safari today?
8%
Tiny.
Hmmm ... This could be taken as an example of what's so screwed up with the computer "market". To make the canonical automotive comparison: If a new make of auto were to capture 8% of the market in just a few weeks, it would be considered one of the most successful product introductions in the history of the industry. If you're anywhere in the "developed" world, try watching any busy stretch of road for a while, and try to spot a car model that makes up even 1% of the traffic.
But in the computer biz, 8% is called "tiny". If your product isn't the market leader and controlling 90% of the market, you aren't worth mentioning (and thus most of your potential customers don't know you exist). Try telling a BMW or Acura owner that their car isn't significant, because it's under 1% of auto sales. But computer people make such comments in all seriousness.
It seems that most of the posts here have totally missed the point. The question wasn't about free software, where the "zero price" definition of free is meant. The question was about OSS, i.e., Open Source Software. This means software whose source code is open and available for examination. And in the schools, the justification should be obvious. Just utter the canonical "Think of the children" mantra.
The reason one wants open-source software is that you want to be able to examine the software to make sure that it really does what it's advertised to do, and nothing else. If your software is closed-source, it can (and probably does) have a number of unadvertised "features" that you can't know about. You should ask yourself "Why doesn't the vendor want us to know about those additional features of the software.
And we have lots of experience with answering this question. It's fairly common for proprietary, binary-only software to collect information about its use and report them back to the vendor. In the case of proprietary educational software, this means that data about your child's behavior is being collected and sent to a remote database that you have no access to.
Closed-source software should be automatically considered a tool for collecting data about the users. So you should be asking the school admins "Do we want to allow software that collects data about our children, and keeps it hidden from us?" Explain to them that unless the software is open-source, they have no defense against such data collection. Only open-source software is available for examination to determine what it's really doing.
Get people thinking this way, and you can probably get them out chasing after the closed-source suporters with pitchforks.
(If you succeed, try to get videos. A lot of us would like to watch the fun. ;-)
If the mass isn't accelerating, there is no force. ...
Much more at Wikipedia for Force.
Well, again, I was curious about this interpretation of the physics, so I took the extreme step of actually reading the article. Even a cursory glance at the first paragraph shows that it doesn't agree at all.
To make it clear, the claim seems to be that if you and I are pushing on opposite sides of an object and it doesn't move, we are exerting no force. This is clearly a possible interpretation of the physics, and there's something that is zero in this scenario. But I don't think it agrees with the definition of "force" that physicists or engineers use.
Thus, the WP article says "In physics, a force is that which can cause an object with mass to change its velocity." Note that little weasel word "can". This statement is consistent with the interpretation that two (non-zero) forces might cancel each other, resulting in no change of velocity. Acceleration isn't required for there to be forces on an object. Actually, it's the other way around; an acceleration shows that there's a (net) force being applied to the object. But forces may be present without a resulting acceleration, if the sum of the force vectors is zero. I am being accelerated by the Earth's mass, but it's ineffectual, because there's a counteracting force, the electrostatic charges in the atoms of the thing that I'm sitting on. Actually, it's not totally ineffectual, because I contain pressure sensors that measure the counteracting force, and those sensors are sending a nonzero signal to my central nervous system.
The WP article reinforces this interpretation with a later statement: "Newton's second law states that an object with a constant mass will accelerate in proportion to the net force acting upon and in inverse proportion to its mass." Note again that it refers to "the net force", not "the force". This is tacit acknowledgement that there may be multiple forces at work, and the acceleration is due to the sum of the applied forces. If that sum is zero, there is no acceleration, but those forces still exist.
I think you're using "force" as a shorthand for what the WP article (and most physicists and engineers) call "net force" or "the sum of all forces" or some such more elaborate phrase.
Maybe we need an explicit term for this concept, so that people don't continue to confuse it with the concept of "force". This term would refer to something that does disappear when all the applied forces sum to zero. But it shouldn't be called "force", because that's already in use for a slightly different concept.
A field, by itself, does not provide energy.
Hmmm ... I've seen a number of comments like that, and I was curious. I'm sitting in a rather strong (gravitational) field that seems to be totally static. Yet I can feel its push, by the pressure my bottom surfaces feel from the chair I'm sitting in, even when I'm not moving. If I hold an object out to the side and release it, it falls to the floor every time. The energy required to produce that motion has to come from somewhere, and the gravitational field seems the only likely source.
Only when something moves perpendicular to the field is energy transferred.
So the energy to the things I've dropped came from my moving them perpendicular to the vertical gravitational field, i.e., when I moved them horizontally? I can easily test this. I picked up one of the objects, carefully lifting it with a vertical motion, and released it. It fell to the floor. So it picked up energy while being moved parallel to the field. The falling speed doesn't seem to vary depending on how I move an object into position before dropping it.
Meanwhile, I made some similar tests with a convenient magnet (taken from the refrigerator door). It seems that the magnet attracts small metallic objects from any direction, no matter how they were moved there relative to the magnetic field. The field is obviously static. So how would you explain this motion, which seems the same regardless of how I move the small objects relative to the magnet?
Maybe the physics of static gravitational and magnetic fields are different in my living room from where you are in the universe ...
Since all of their little film-cells rotate in the same direction, this says to me that there is an unaccounted-for field which is breaking the symmetry and starting the effect.
Huh? In that video that's linked to, the film begins with a visible counter-clockwise rotation, and after a few seconds, it visibly halts. Then it begin again with a clockwise rotation. This seems to be initiated by some motion along the top edge of the cell.
So what are you seeing that's different from what's running on my screen?
The URL for the video I'm looking at is "http://softmatter.cscm.ir/FilmMotor/movies/movie.1.wmv". Do others see the rotation differently than I do? On my screen, in a firefox 3.0.6 window, the change in rotation direction seems very obvious to my eyes.
The government is democratically elected. It is not a free democracy however because all candidates have to be approved by the ulama. ...
Hmmm ... If you substitute "the two major political parties" for "the ulama", it sound very much like the US. Some other democracies have three major parties, but people are often pointing out that the number doesn't really matter. What matters is that a small unelected oligarchy controls who can run for office.
So maybe this is an inherent part of human societies. What's the chance that we can ever do anything that works better? Just changing the name that the media uses for the oligarchy doesn't seem to much affect the outcome.
Hmm ... a "troll" rating and a serious reply. And I even kept the "Good Joke" title. Maybe I should remind myself that /. is full of the humor-impaired who don't recognize intended humor without a ;-).
Law or no law, if my router doesn't capture it I am not capturing it. I don't know how to do it, nor will I pay someone to do it.
Actually, I'd sorta like to know how to do this. We've had a couple of wifi gadgets in our house, and none seems to have any (documented) way to collect such data. Right now we have an Apple Airport. I've asked around a bit, googled, etc, but I haven't found any way to make it tell any of our computers who's connected or how much data they're sending. I'd like to be able to monitor this myself, but if it's possible, Apple isn't telling. Or maybe they would, if I knew the right magic words to ask about.
In general, this could be useful information for people using wifi. We probably won't get it without some way of pressuring the vendors to tell us how it works, which is probably different for every one of them.
(Yes, I know about SNMP. I've implemented SNMP agents and clients. I know where the info should be in the MIB. I also know how vendors can make SNMP quite incompatible if they want to; I've worked on projects where management ordered us to do that. The Airport has those four letters in its config stuff, but I've never got it to respond to a query from a client. Similarly for other brands. If I can't make it work, I can't imagine that your typical home user would have any chance at all. ;-)
[U]nless if they are continually pushed to a secure location you could alter them the second that you receive a notice from law enforcement to provide them with logs.
Well, there's an obvious solution to that. Just require that all log data be instantly transmitted to a government repository for archiving. This would also eliminate the need for home wifi users to purchase expensive storage devices to hold the logs. Instead, we'd just have a government agency with funding to buy a few terabytes of disk space per day to store all the logs.
Think of the economic stimulus from the huge purchases of storage devices by this agency ...
Actually, your mistake wasn't forgetting the </i> tag; it was neglecting to hit the Preview button that's right next to the Submit button.
(Hey, let's see what happens if I don't preview this. ;-)
It works fine so long as you are CAREFUL.
Sometimes it takes more than being careful; you also have to understand how some of the crazy browsers can screw things up.
I learned this some years ago, when I first found /. and did a bit of moderation. I've always liked that way that most (but not all) browsers will scroll down about .95 pages if you tap the space bar. But I found that this didn't always work. With /., sometimes hitting the space bar worked, and sometimes it seemed to do nothing. I'd hit Space a few times, mutter "WTF???", reach for the mouse, move to the scroll bar, and do it that way.
It was quite a few incididents like this before I finally discovered what was happening. It turned out that, if I had used a menu for moderation, after that the browser would interpret a space as meaning to scroll the menu down one item. This can be hard to spot, because of course your eye is aimed at the bottom of the screen, not at the menu that's up higher.
When I discovered what the browser was doing to me (or to the author of the post that I'd now mis-moderated), I was of course duly shamed, but there was nothing I knew to do about it. It took me some time to learn about undoing moderations by posting.
So being careful isn't enough. If you don't understand such obscure misbehaviors of your browser, you'll just very carefully do the wrong thing. And if the change is small enough to not attract your eye, you won't understand what was done; you'll just think that the damn browser has just forgotten how to scroll.
It's just one of many ways that the current GUIs in general (and the flock of browsers in particular) is user-hostile in so many little ways. Telling users to be CAREFUL doesn't do it. We should find a way to fix such things that seem designed to trick users into doing the wrong thing.
[c]an you provide citations that Wikipedia's aggregate quality has improved?
Certainly. I found several of them by just reading this discussion. And a quick scan of the messages below this one shows several more. And there have been many other /. discussions with similar citable claims. But don't use the /. search thingy; it ain't worth a damn. Use google. ;-)
I got "Funny", "Informative" and "Flamebait" mods for this one. (And the "Overrated" mod seems to have disappeared.)
This rating has surpassed all my previous ratings for incongruity. I'll have to keep a link to it, as a nice example of how screwy the moderation can get around here.
It is impressive how poor a sense of humor a lot of the folks here seem to have. Maybe I should have included a smiled. But I really thought it would be redundant this time.
Yeah; I was a bit surprised by that "+5 Informative" rating. But I clicked on it and got the details. Only one mod was "Informative". Another was "Funny", which was what I was going for. The other was "Underrated", which has me a bit puzzled.
And I well remember when I was little, and was sent to Sunday School at several different churches as we moved around every few years. In every one of them, I heard "teaching" that if you truly believe in God, and pray to Him (and tithe ;-), you'll get very rich. Lots of other religious people have, so you can, too.