Wikipedia:Reference desk/Archives/Computing/2009 February 26

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February 26

Cell phone tracking

I've lost my cell phone, it's still on but it's on silent. How can I find it? Are there any online tracking tools that can give me the approximate city it's in? -- penubag  (talk) 01:36, 26 February 2009 (UTC)

You probably won't be able to track it unless you've enabled something like Google Latitude. --Aseld ^talk 01:47, 26 February 2009 (UTC)

City? I don't think that it being on silent is going to matter if you don't know what city it's in. Have you lost your mobile or have you lost your girlfriend? I certainly hope that a publicly available way to track any mobile is NOT available yet. I'm sure it "can" technically be done, but I highly doubt you could get access to that information unless you are a law enforcement body with an appropriate subpoena. Vespine (talk) 04:07, 26 February 2009 (UTC)

Warrants? We don't need no stinkin' warrants. – 74  05:19, 26 February 2009 (UTC)

It is too late once it is lost, but there are programs you can put on your phone (when you have it) that will allow you to track it online, such as loopt. -- kainaw™ 05:19, 26 February 2009 (UTC)

Back when I worked for US mobile carriers (AT&T Wireless, Cingular), any customer service agenct could see which tower the cell was using (if it was on), which gives a general location. They weren't supposed to give callers this information though (stalkers!). There was a linegroup set up for police inquiries though. I don't know what the verification process was there.

In Canada, many providers have a "child-find" application that uses assisted GPS to locate the phone. Although some phones run childfind as an "application" on the phone (you'd have to install it) or a fee-based service (you'd have to pay for it), I know that Telus has it going all the time. You just have to log into your Telus online account and ask a CSR for some code. I'm sure some other providers are similar. When you call the contact center, just be bothersome. Some people don't know or follow the rules and will give in when pressed by customers.NByz (talk) 18:03, 26 February 2009 (UTC)

If the phone has text capabilities, send a text stating that you are the owner and you seek to obtain your phone. With some luck, someone may have found it and they will contact you. Of course you could try to call (as I guess you probably already did) but some people may respond to a text rather than an incoming call on a phone they just found. This all of course depends on whether or not someone even found your phone, and it is not lying lonely in a remote environment. I once found a phone on the sidewalk...I scrolled through all the numbers until I saw one listed as "Mom". I called the number and the owner met me rather quickly to get his phone back. best of luck to you. You may want to call the phone service provider as well so you don't get charged for calls you didn't make in the case someone is using it 10draftsdeep (talk) 18:39, 26 February 2009 (UTC)

identify the '80s video game

Can anyone identify the game I played on a friend's new Sinclair QL many years ago? It was a 2D (side-on) view of a spaceship exploring a multi-screen cavern complex (collecting items, perhaps?) and I believe it had come bundled with the machine. I thought it was called Citadel, but a description I found on the web of Eidersoft's game of that name doesn't match my recollection.

... and is there somewhere I can download it? or see source? or screenshots? or anything? —Preceding unsigned comment added by 66.30.119.23 (talk) 02:26, 26 February 2009 (UTC)

My first instinct is Asteroid or Phoenix but I'm probably wrong. -- penubag  (talk) 02:36, 26 February 2009 (UTC)

Sounds like Defender to me (or any one of a number of very similar games). Defender was very popular in gaming arcades around that time (mid 1980's) and therefore a likely target for bundling with a home computer. Alternatively, take a look at this list of QL games and see if any of the names jog your memory. Astronaut (talk) 14:17, 26 February 2009 (UTC)

Additionally, Stargate (video game) might be a possibility. cheers, 10draftsdeep (talk) 14:43, 26 February 2009 (UTC)

Can any Windows XP Home Edition Cd-rom be used with any XP Home computer?

I have a second-hand XP Home computer that does not have any Wiindows disks to go with it. If I bought a Windows XP Home Edition Cd-rom from ebay or somewhere, would I be able to use it for 'repairs' without complications? And is it possible to create an ersatz Windows XP Home Edition Cd-rom using for example the files in the i386 folder, or in the set of floppy disk set-up files that MS rather puzzlingly makes available? 78.149.135.197 (talk) 02:28, 26 February 2009 (UTC)

There might be complications, although I'm sure you'll be able to work around them. You see, it's not the disk that matters to Windows. It's the serial number. If it's a real serial number, Windows XP will install. However, after installation is complete, Windows will record the ID numbers of the hardware in the computer and associate them with the serial number. Thus, often, activation will not work on more than one computer because Windows will check online and see that the CD has been used on more than one computer. Nevertheless, in such a case, once activation fails, you can call Microsoft to activate the software. They will ask you for the faint numbers imprinted on the back of the CD, which will prove that the CD is genuine. Also, if your computer came installed with Windows XP, you often can find the serial number on a sticker on the case. You can use any CD or DVD to install Windows, and if the serial number hasn't been used on any other computer, activation will work.--K;;m5m k;;m5m (talk) 03:52, 26 February 2009 (UTC)

There's also one exception. If it's a true "store purchased" XP CD - then everything K;;m5m said applies. If, however you're trying to use an OEM (Original Equipment Manufacturer-er) disk - which is more of a restore disk than the actual OS - it can fail. Meaning that if you got a "System Restore" disk from Compaq when you purchased the computer - and you try to use it to install XP to a Dell computer - the disk will read the hardware as not valid - and fail. — Ched (talk) 05:57, 26 February 2009 (UTC)

There are really many kinds of Windows disk that people call "OEM". One is a regular install disk that MS sells to OEMs (really to very small scale system builders); this is essentially just like a regular install disk, but it comes in basic packaging (just a little cardboard sleeve with a licence sticker). Then there's the small system builder's kit (which is for builders who build a few hundred or a few thousand PCs a year); this lets them make custom install disks, and the associated programme sells them licence stickers wholesale. Then there's the special arrangements for large builders, the details of which vary between manufacturers (and are generally secret). Of these the first kind should work fine on any machine, the second might or might not (for the reasons others have answered above), and the third will almost certainly not. Mimetic Polyalloy (talk) 15:15, 26 February 2009 (UTC)

Does this mean that a second-hand disk off eBay will not be any use for a repair-install to fix problems, because someone has used it before? That only a new disk will be useable? The computer I have has been verified as having genuine Windows after I installed SP3. 78.146.52.210 (talk) 19:08, 26 February 2009 (UTC)

Without rereading everything - if you use the number on the sticker of your computer, you can install. At worst - you'll need to call the 1-800 number for the activation key. If you don't have a valid number, and I hesitate to mention this - you could always google Devils Own, xp.... BUT be advised, that's an easy way to pick up a virus/trojan dropper - and use of such numbers are not legal. (at least in the US) — Ched (talk) 04:02, 27 February 2009 (UTC)

I work in a computer shop and work with this a lot.

- Retail stickers need retail XP CDs.

- OEM stickers need OEM, NON-BRANDED XP CDs (generally)

-- 'OEM stickers' includes the key affixed to the side of your computer by the computer manufacturer (as required by Microsoft). That key is probably not what is actually being used on the computer (read on for why).

Both retail and non-branded OEM disks will allow you to do a repair install (but requiring retail or OEM keys, respectively). Most branded OEM disks I've seen won't do a repair install, and actually use a volume-license install key (so you don't actually have to enter the key on the side of the computer). Of course, that's moot if you need it for a repair install.

Installs are linked to key, not disk. I've got multiple copies of the same XP SP2 disk, slipstreamed with SP3, to reinstall computers all the time. (Washii) 63.135.50.87 (talk) 23:52, 27 February 2009 (UTC)

Oh, also: you can tell what kind of disk (retail/OEM/volume license) you're using by comparing the full volume label to a listing, like at TackTech [1] (Washii) 63.135.50.87 (talk) 23:57, 27 February 2009 (UTC)

Installing GNOME in FreeBSD

Hi. I decided to install GNOME in FreeBSD, so went to the /usr/ports/x11/gnome2 dir. and typed make, then make install clean. That was nine hours ago. It seems to be downloading and compiling a bunch of packages, now. I'd really like to use my laptop. My internet connection is really slow today (35 kbps even though it's supposed to be broadband). It's on tetex-texmf right now. It's not a slow computer -- 1 GB of RAM, 7200 RPM HDD, and a 2.5 GHz CPU. Will it probably be over soon?--K;;m5m k;;m5m (talk) 04:23, 26 February 2009 (UTC)

Running .iso directly from HD

Is it possible to run an .iso directly from the Hard Drive or do I need to put it on a CD? I am using an Acer Aspire One, and it has no CD-ROM drive. Is there a way to get this .iso onto the PC (I am downloading it from a HP Laptop).--KageTora (talk) 08:45, 26 February 2009 (UTC)

Yes - you'll need a CD emulator - I think that Virtual drive is the closet article we have, but look here and here. If you still have questions, drop me a line at my talk page and I'll try to help get you aimed in the right direction — Ched (talk) 09:29, 26 February 2009 (UTC)

Magic Disk is a nice simple Windows program which will mount an ISO image so that it appears as a cd drive to the OS, or if you're using Linux I think there is a loop device which can do this. But it depends what you're trying to do; just installing a game or software from the image will work fine but if you want to for example install a complete Windows XP you'll have to go about it a different way, see here SN0WKITT3N 10:11, 26 February 2009 (UTC)

Here's] how to do it in unix/linux. 87.112.17.229 (talk) 13:23, 26 February 2009 (UTC)

To be perfectly honest, it is Mac OSX Leopard I am trying to install on a Windows XP machine. Shush! But, anyway, 'for information purposes only', how would I go about this?--KageTora (talk) 14:09, 26 February 2009 (UTC)

You can't install OSX on a regular X86 machine -the installer checks for apple-specific hardware on the motherboard. There are hacks and patches to allow this to work (on a few motherboards), but those are probably illegal and certainly for the very technical only. Mimetic Polyalloy (talk) 15:08, 26 February 2009 (UTC)

I don't think it's only "a few motherboards"; see this website. And what's illegal about it? (If you're thinking of minatory language in the EULA, consider its actual significance.) -- Hoary (talk) 02:46, 27 February 2009 (UTC)

You're not going to be able to install an operating system from a virtual disk drive. Not easily anyway. You might be able to make a bootable USB device, though. APL (talk) 18:01, 26 February 2009 (UTC)

Yeah, it is not possible to install most OS from virtual drive, but few are possible. It is possible to install ubuntu from local iso image (wubi), and it is possible to install OS in virtual machines (although these usually does not requires virtual drive and can mount image internally). -Yyy (talk) 08:05, 27 February 2009 (UTC)

Map Network printer using a .bat file

Hi all, I need to create a .BAT file that will install a network printer . The .BAT file should use the Net Use command. Can anyone help? Thank you in advance. --80.88.251.210 (talk) 13:11, 26 February 2009 (UTC)

Wireless connection problem

Hello, I'm hoping to get help with a problem. Sometime between 1 a.m. yesterday and 7 this morning my laptop decided to stop recognizing wireless signals -- my own, others in the neighborhood and now those at work. I have a dial-up connection, but it's woefully inadequate. Is there anything I should do, besides rebooting, that I can do? I don't think I turned anything off inadvertently, but anything's possible. I run Windows XP if that makes any difference. Thanks for any and all help. —Preceding unsigned comment added by 4.239.216.32 (talk) 15:11, 26 February 2009 (UTC)

If you tell us specifically what make and model of laptop you have, we may be able to help you better. There are often hidden (or at least not-well-marked) buttons or switches that control the wireless functions. --LarryMac | Talk 15:35, 26 February 2009 (UTC)

I use a Dell Latitude D620. Thanks. 4.239.216.32 (talk) 15:44, 26 February 2009 (UTC)

I'm using a D630 right now -- look at the picture on this page, under the heading "Wireless Communications", about 2/3 down the page. You may have inadvertantly moved that switch - they say "to the left", it would be "to the rear" if you're actually using the computer. --LarryMac | Talk 16:03, 26 February 2009 (UTC)

That did it. As someone said on your talk page a while back, you do rock!4.239.216.32 (talk) 16:21, 26 February 2009 (UTC)

Really annoying noise

I have a Lenovo Thinkpad T60p. Runs XP. Everything about it's pretty perfect except: when I simultaneously push any two arrow keys in addition to the upward arrow key, it makes and annoying error beep noise. I've disabled all of the regular computer noises through the sounds thing in Control Panel. This is the only one that keeps annoying the hell out of me (and the noise it makes when it's plugged in, but that's less irritating). If I'm, say, avoiding my homework by playing some online game while listening to music on earphones, if I by mistake push three directional buttons, the beep comes REALLY LOUD in the middle of my music. Very unpleasant. Any ideas of how to deal with this (and, while I'm at it, the plug-in noise)? Thanks, 140.247.41.80 (talk) 18:48, 26 February 2009 (UTC)

That sounds like the keyboard microcontroller sounding the motherboard's onboard piezo-electric "bell", in response to you pressing more keys than the keyboard matrix can decode. You might be able to disable this tone in the BIOS. 87.112.17.229 (talk) 19:11, 26 February 2009 (UTC)

PC Speaker Usually you can't disable it in the BIOS, actually, but you can disable the driver for it. Here's some instructions for windows: [2] Indeterminate (talk) 19:16, 26 February 2009 (UTC)

Internet volume control

I've been wondering for a while -- is there any way (firefox add-on, etc) to control specifically internet volume? Like mute the internet (or tone it down), while not touching other volume? I've been looking around and can't find anything, and I'd use something like that all the time. 140.247.41.80 (talk) 18:50, 26 February 2009 (UTC)

Windows Vista has an OS-level per-app volume control (over and above any volume settings a given app may have internally). XP doesn't have that feature. I don't know about other OSes. 87.112.17.229 (talk) 19:05, 26 February 2009 (UTC)

So if I have (and plan on keeping) XP, there's no real solution? —Preceding unsigned comment added by 140.247.41.80 (talk) 19:19, 26 February 2009 (UTC)

I can sympathize. Many Internet apps (like games) will have their own volume settings (although some are limited to on and off), so that's one option. StuRat (talk) 19:38, 26 February 2009 (UTC)

I would recommend Flashmute. Mahahahaneapneap (talk) 00:59, 2 March 2009 (UTC)

Disabling autorun under XP

A few weeks ago I asked here about disabling autorun under XP. The standard answers didn't help me. It now looks as though Microsoft has finally admitted the problem and come up with a fix, so I hope it's okay to post a link here for anyone else having the same problem. [3]--Shantavira|^{feed me} 19:02, 26 February 2009 (UTC)

Of course, and thank you. I tried following the instructions, and managed, after some fiddling. The link to the English Microsoft page doesn't work for a non-English version of the OS. So I googled "KB950582 oppdatering" (KB950582 update), and found the relevant Microsoft page in Norwegian. However, the utlility "Gpedit.msc" that is referred to in the article was not installed after the update. So I followed the manual instructions, and added the registry key NoDriveTypeAutoRun (REG_DWORD), which I assigned the value 0xFF, which should disable AutoPlay on all kinds of drives. (Location: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer\). And that annoying dialog that comes up whenever I plug a usb device to the PC is gone, the drives just appear in "My Computer". --NorwegianBlue ^talk 00:01, 27 February 2009 (UTC)

If the universe is a computer, can it be hacked?

Some experts have suggested, e.g. at [4], that the universe may be running on a computer. If this is true, is it likely that this computer can be hacked from within in order to view (without the limitations of the black-box testing we're doing now) or change the laws of physics? How might vulnerability to such hacking be tested for? NeonMerlin 19:21, 26 February 2009 (UTC)

If there are hypothetical supercomputers out there running simulations so complex, we wouldnt be able to tell the reality from the virtual, I'm sure some asshole will get it in to his head to hack it and ruin it for all of us. Livewireo (talk) 19:32, 26 February 2009 (UTC)

But what if the first person to hack it wasn't an asshole and wanted to use his or her powers for good? NeonMerlin 21:37, 26 February 2009 (UTC)

It's kind of hard for me to imagine much good coming out of changing the laws of physics. "Hey guys in order to reduce energy loss I've lowered the rate of entropy dissipation OH NO I BROKE ALL ECOSYSTEMS AT THE SAME TIME" --98.217.14.211 (talk) 22:17, 26 February 2009 (UTC)

The universe may be a finely-tuned watch, but sooner or later it will need a new battery. NeonMerlin 04:05, 27 February 2009 (UTC)

If the universe has some sort of security or general protection protocols that need to be hacked, presumably whoever put those security protocols there wants them there.

I'd be pretty pissed if The Sims started randomly mucking about in my computer's ram. Even if they did it with the best of intentions, it would not end well for the Sims. APL (talk) 16:31, 27 February 2009 (UTC)

You would eradicate a potential new life form because it was inconvenient? If the universe is a computer simulation I certainly hope our Owner is more understanding. – 74  18:17, 27 February 2009 (UTC)

If you follow that assumption (which I find rather childish)... We are not intelligent beings. We are nothing more than data representations in a simulation. So, asking if we can hack the computer is equivalent to asking if that little ghost in pacman can hack my computer. Sure, there are movies (ie: Tron) in which we fantasize about the parts of a computer being truly intelligent. They aren't. They are just a bunch of changing ones and zeros. So, we can live in a disillusion that we are intelligent, but that doesn't make it so - especially when confronted with an understanding that we are just little blips in a computer simulation. -- kainaw™ 21:45, 26 February 2009 (UTC)

So in your opinion we should give up on AI now because you've determined it's not possible? I don't find the possibility of artificial intelligence any more outrageous than the original computer simulation premise. If the world is an elaborate simulation, then we are part of that simulation, presumably as artificially intelligent constructs. Is there some inherent quality of life that prevents a machine from being self-aware? From holding beliefs? From being "alive"? Last time I checked we hadn't found any such "magic". If you get technical enough, humans are very advanced biological computers: we accept inputs, process, and produce outputs. – 74  22:10, 26 February 2009 (UTC)

This hypothetical situation calls for a few premises:

• 1) We would need to know that such a computer exists
• 2) We would need to be able to somehow interface with said computer with one of our own computers.
• 3) We would need to what language the computer was written in to be able to alter it with our super hacking powers.
• 4) We would have to have the mental capacity to understand that we are really just simulations of a computer and not real. This would probably be the hardest to come to grips with.

This also doesnt bring in to play how we first came in contact with said computer, who made it, WHY they made it and so on and so forth. Livewireo (talk) 22:24, 26 February 2009 (UTC)

The relevant article for this is simulation hypothesis, although that's something of a cranio-rectal eversion, and Wikipedia doesn't give medical advice :) 87.112.17.229 (talk) 22:32, 26 February 2009 (UTC)

The Thirteenth Floor, Existenz and The Matrix All great movies in my opinion. . Also "we are data representations in a simulation" != "we are not intelligent". Vespine (talk) 22:41, 26 February 2009 (UTC)

kainaw, If you're going to make a statement like that you're going to have to explain why biological machines are "intelligent beings" but an element of a theoretical computer (of unknown nature) of vastly more complexity is automatically not an "intelligent being". Because that seems incredibly counter-intuitive to me. Why would you assume that the unknown computer of vast complexity was incapable of doing something that a (relatively) simple biological process was capable of? APL (talk) 16:31, 27 February 2009 (UTC)

In the sense that "hacking" is achieving unexpected outcomes beyond the originator's control (and accepting the hypothetical computer simulation premise), we have already accomplished it. The laws of physics change dramatically at a small enough scale (one of the factors motivating the computer simulation hypothesis), allowing us to perform quantum teleportation, for instance. Unless the simulation was designed to allow that, I'd call it a hack. We may never be able to view the "source code" for the universe (and probably wouldn't understand it if we did), but we could (and would) certainly exploit any inconsistencies in the system for our own benefit. An example: in a simulation there would be no reason why a process couldn't create energy, just rules preventing it. Finding an "infinite energy source" would require circumventing the rules, but would almost certainly be beneficial to humankind (unless the simulation was summarily canceled because of the discovery). – 74  22:48, 26 February 2009 (UTC)

My feeling would be "no". The laws of physics are going to be the processor architecture. The processor is not going to be able to modify itself. --98.217.14.211 (talk) 23:48, 26 February 2009 (UTC)

A computer program can hack another computer program, but I don't think one could ever actually hack itself... --Alinnisawest,^{Dalek Empress} (extermination requests here) 01:27, 27 February 2009 (UTC)

You stated it much better than I did. If we are nothing more than some constructs in a computer program, then we are constructs of a computer program. We do what we have been programmed to do. If our programming has designed us to, in some way, alter the laws of physics in the simulation, then that is the purpose of the program. It is not a hack. At most, it is bug in the program. So, are you asking if God ignored the compiler warnings when he compiled this simulation? -- kainaw™ 01:41, 27 February 2009 (UTC)

If you assume that an artificial construct cannot have "free will" then your result follows. The key difference between a "hack" and a "bug" is intent; without free will a construct cannot have "intent" to do anything that the Programmer didn't intend. With free will, the construct can have intent to exploit the simulation (beyond the Programmer's intentions), thus qualifying as a hack. – 74  03:03, 27 February 2009 (UTC)

Alinnisawest, if genetic programming is combined with self-modifying code then AFAICT a program can do things its author never specifically intended, even without having bugs and even without interacting with another program. NeonMerlin 04:02, 27 February 2009 (UTC)

Sure a simulation of a computer can 'hack' the computer it's running on - this happens all the time. Lots of programming languages (Java, for example) run in a 'virtual machine' environment - or a 'sand box' (see JVM for example). It has long been known that errors in the implementation of the virtual machine in some versions of Java have allowed programs to 'escape' the sandbox. Most exploits are things like buffer overruns that allow arbitrary code to be pushed onto the stack and executed. Suppose the computer that runs our universe has code like:

 class Proton : public Hadron
 {
    class Quark quarks [ 3 ] ;
    ...
 } ;

...then somewhere in the code, something allows for more than three quarks to be shoved into the Proton when it undergoes some kind of collision. So you turn on the LHC - create some new condition that hasn't happened since the big bang (and certainly not since the ultra-being's ultra-geeks switched over to UNIVERSE 2.0.0 - LEARNING EDITION). Now - for some reason related to finding the Higgs Boson - more than three quarks get somehow stuffed into a Proton and suddenly there is a possibility of an exploit that would allow one to run arbitrary code on the ultra-computer on which our universe runs.

The problem is not so much in figuring out how to effect a buffer-overflow exploit in this hypothetical machine - it's how to understand how to make use of the exploit - given that there is no documentation for this computer. Without knowing the instruction set of the target machine - and without any examples or documentation to follow - it seems rather unlikely that we'd ever be able to figure it out. After all - any oddities we've ever discovered in the laws of nature are simply things to be noted - we have no way to know whether weird stuff like quantum theory and (especially) relativity are in fact due to bugs in the simulator - or whether they are just weird and arbitrary limits set up by the uber-being that runs our machine. SteveBaker (talk) 04:13, 27 February 2009 (UTC)

Surely you mean

class Particle {
  Particle(const Particle&); // not implemented
  mutable bool on_shell;
  volatile q_int spin[3];    // NB: reading any one changes the other two
  // ...
public:
  //HACK: arguments are only honored approximately
  Particle(Vector4 event,Vector4 e_moment);

  //TODO: support gravitons

  // ...
};

// ...

// TODO: should this be refactored into smaller particles?
class Quark : public Particle {/*...*/};

class Baryon : public Hadron,Fermion {
  Quark *quarks[3];
public:
  Baryon(Quark *a,Quark *b,Quark *c);
  // ...
};

class Proton : public Baryon {
public:
  Proton(Up *a,Up *b,Down *c) : Baryon(a,b,c) {/*...*/}

  double getHalfLife(); // BUG: is it okay to return +inf here?

  // ...
};

We can't have Lambda, CharmedXi, TripleBottomOmega, AntiNeutron, etc., each declaring their own array of 3 quarks, now can we? And quarks (despite being indistinguishable) have identity semantics, surely, since we can create hadrons out of existing quarks. I wonder if this is exception-safe, or if it can leak entropy when the Cosmic AC throws bad_alloc... --Tardis (talk) 17:17, 27 February 2009 (UTC)

Perhaps instead of causing a buffer overflow, we could find an improperly terminated array and read past the end of a buffer. In Steve's example, if we found a way to extract an arbitrary number of quarks from a proton we could use that to read potentially a LOT of the data the universe runs on. If the universe's computer doesn't have any sort of memory protection, then perhaps we could even read out data not related to our simulation. That could be interesting. We could read God's emails.

There's still basic problems, however. That data would have to be decoded. God's emails probably aren't in ASCII. And there would be a very serious danger that reading things we weren't supposed to would cause a fault, or some other bad side effect. APL (talk) 20:03, 27 February 2009 (UTC)

If you're interested in stuff like this (strange loops and things that break out of their own little universes), I HIGHLY recommend you read Gödel, Escher, Bach. It will blow your mind. Seriously, you will not be able to think a cogent thought for a week after reading that book. Not only that, it's extremely fun (it features many charming dialogs between Achilles and the Tortoise and their various wacky adventures) and interesting as well as totally mindf***ing. Belisarius (talk) 06:46, 27 February 2009 (UTC)

For the people who claim that a simulated being can't hack the simulator, here is a theoretical example. Imagine if we discovered that supposedly random phenomena were actually governed by a pseudo-random generator. Further imagine that the universe is divided into cubic meters, (poss. for parallel,distributed computing.) You could construct a device that would perform a vast number of some reactions that would request a random number until the pseudo-random generator was in some desirable state. Bam. You've just altered the probability of quantum physics reactions in that cubic meter of space. I'm sure some clever physicist could come up with something useful to do with that power.

Now, admittedly, this isn't a "hack" in the sense that there is no opportunity to execute arbitrary code or to corrupt memory outside of the simulator, but Steve already explained why that would be problematic anyway. This is a 'hack' in the sense that it's exploiting a vulnerability in the universe's 'fairness', like writing a program that predicts the shuffle on an online poker site.

Who knows if we'd recognize this sort of exploit as a simulator error or just a peculiar law of physics. I suppose it depends on how blatant it is. APL (talk) 16:49, 27 February 2009 (UTC)

Yes, the universe does run just like a computer, but its so darn big that changing one thing in one corner is unlikely to make any real difference in the scheme of things. The last hack we know of took place 4 billion years ago, and the result was us. But noone else in the universe cares. I too highly recommend Gödel, Escher, Bach. -- Fullstop (talk) 17:27, 27 February 2009 (UTC)

So, to summarize, this has all come down to: If we redefine "hack" to mean "find a bug in a program" and redefine "intelligent life" to mean "any part of a program that may come across a bug in a program", then it is possible for a part of a program that may come across a bug in a program to find a bug in a program. I find that a huge rationalization of the question. The question appears to me to ask if it is possible for us to hack the program. In other words, we must escape the confines of the simulation, somehow gain the ability to develop and execute code on the computer running the simulation, and then execute our hack. It is really easy get the answer you want when you rationalize new definitions for common words, but not so easy if you stick to the original meaning of the words. -- kainaw™ 19:18, 27 February 2009 (UTC)

I think you'll find the definition of "hack" isn't nearly as clear as you make it out to be. "Hacking" is (ab)used for techniques like disabling javascript and manually modifying URLs, but a generally-accepted definition would be "Unauthorized attempts to bypass the security mechanisms of an information system or network." I challenge you to cite a computer hack (as defined in the prior sentence) that does not make use of a bug. Meanwhile, as I have stated several times before, the premise that we are inside a computer simulation does not invalidate our presumption that we are "intelligent life"—we don't turn into mindless automatons simply because we are no longer biological in function. Simply put, we disagree on what the "standard" definitions and assumptions are in this case. – 74  20:01, 27 February 2009 (UTC)

To some extent, this has already happened with some of our own 'virtual universe' software. Several people who have attempted to use software to use evolutionary techniques to 'evolve' artificial creatures in a virtual world have found that these creatures will evolve to exploit bugs in their software. For example, in one case such a system was set up to limit the amount of energy in the virtual world in an effort to create creatures who would hunt each other for food. After some large number of evolutionary steps, it was found that the dominant 'species' of creature in the simulation was a stationary 'blob' that made its living entirely by reproducing - then immediately eating it's offspring. It had evolved to be precisely the right size such that the energy lost by reproducing plus the exact same amount of energy gained back when eating it's young resulted a tiny round-off error in the floating point math. They'd evolved to (in effect) subtract one very large number from another in such a way that the roundoff was always in their favor. In another case, someone was attempting to evolve creatures that could move in interesting ways by setting up an evolutionary system where the probability of reproduction depended on the distance the creature could move in a certain amount of time. He found that all of the creatures evolved as simple mindless tall/thin vertical columns! When they were tested for their speed, these columns simply fell over. Since his software used only the center of gravity of the creature in the X/Y plane to determine where it was at any given time - they appeared to be moving very rapidly and therefore outperformed and out-evolved creatures that were evolving more interesting things like legs or wheels. So any bugs that might be exploited for gain would probably just be a part of the way we see physics work. SteveBaker (talk) 14:28, 28 February 2009 (UTC)

I don't see exploiting a bug for gain as a hack. What if eating meat is a bug in the system? Are we to claim that we are hacking the system because we eat meat? Youth in Asia (talk) 14:34, 28 February 2009 (UTC)

Problem in Windows XP SP2,

Ok, let me tell everything. I installed Windows XP SP2 on my Compaq 7500 Desktop Presario aa month ago. First everything was going just right, but hey, after the second week, tried to run Dungeon Siege 2 on PC. Not running, saying ;D3D Initialization failed'. Lol, installed ATI Display driver, but did not work! My video card is ATI. Any suggestion? Just kidding here. 115.241.78.80 (talk) 19:56, 26 February 2009 (UTC)

Hello. I think you should try to replace Windows XP SP2 with SP1 instead. I had the same type of problem once, and the expert asked me to do the same. And, it worked indeed. Thank you. Anirban16chatterjee (talk) 20:04, 26 February 2009 (UTC)

Better yet, update to SP3. After that, make sure you have the most up to date ATI driver (from ATI's site, not from the disk that came with your computer). You may also have to install the latest DirectX from microsoft's site. 87.112.17.229 (talk) 20:22, 26 February 2009 (UTC)

Don't attempt to go back to SP1, that would be foolish. After doing what 87.112 says, also make sure that all recommended Direct 3D features are enabled. --LarryMac | Talk 20:24, 26 February 2009 (UTC)

But has SP3 enabled with the feature? I have not yet tried, and so I am simply asking. Anirban16chatterjee (talk) 20:56, 26 February 2009 (UTC)

Do the SP3 upgrade for sure, I don't think it will make a difference with your video problems but it is important. Which specific ATI card do you have? If it is an AGP card the latest drivers will not work for you. ATI long ago decided to drop all support for AGP cards. I recommend intalling the Omega drivers from [5]Worked wonders for me when I was trying to get an AGP card to work a few moths ago. 161.222.160.8 (talk) 00:12, 27 February 2009 (UTC)

…

Why isn't the character … (yes, that's one character, not 3 dots) used in any webpages? (Google proof) I realize that I've completely spoiled my little secret by putting the character on this page, so now Google will see this page, but why isn't that character used at all, anywhere on the 'net? I was typing three dots into MS Word, and it auto-replaced the three dots with this. flaminglawyer 21:12, 26 February 2009 (UTC)

Because Google generally ignores punctuation when indexing and searching. NeonMerlin 21:36, 26 February 2009 (UTC)

(ec)Google proves no such thing. The ellipsis character is used on plenty of pages, not least the Wikipedia Ellipsis. Try searching Google for a single period, or colon, or comma, and it doesn't find any pages either. Moreover it seems it finds no entries for longer strings of punctuation, like >= ^^ *** and so forth. It's because Google builds its index on strings of regular letters and numbers, which it assumes will be meaningful for people. One of the first things it does when processing a page for indexing is to chuck out all the punctuation, elipses, and so forth. 87.112.17.229 (talk) 21:38, 26 February 2009 (UTC)

Oh. I feel stupid now. flaminglawyer 21:52, 26 February 2009 (UTC)

The path to enlightenment is composed entirely of a succession of progressively stupider questions. 87.112.17.229 (talk) 21:59, 26 February 2009 (UTC)

A question that comes up every once in a while here is how do I google for "hello.world" (for example), the answer is you can't. Vespine (talk) 22:20, 26 February 2009 (UTC)

Well, you could say: 1) Get rich. 2) Buy Google. 3) Rewrite the search algorithm. 4) Search for "hello.world". -- kainaw™ 23:09, 26 February 2009 (UTC)

Wait a sec, this means that you can't search for punctuation at all?! Ah, what a tragedy. flaminglawyer 01:05, 27 February 2009 (UTC)

One exception is that Google remembers any amount of plus signs at the end of words. You can get results for C++, the programming language, but also a+, a++, a+++, boy+, fish++, dog+++, etc. --Bavi H (talk) 04:10, 27 February 2009 (UTC)

@Vespine: What are you talking about? I can do a google search for hello.world, and it works just fine. flaminglawyer 05:58, 27 February 2009 (UTC)

No, you can do a Google search for hello.world and it returns results of the form hello*world where * is zero or more characters of punctuation and/or whitespace. You cannot isolate results where * is exactly a period. – 74  06:55, 27 February 2009 (UTC)

Try Googling the band !!! and you'll get nothing. In order to find them, you have to type "chk, chk, chk" in order to get results, something that has earned them the title as the hardest band to Google. --Whip it! ^{Now whip it good!} 23:56, 27 February 2009 (UTC)

Malware in Lisp

Does any virus or worm have its propagation mechanism written in Lisp, or does any trojan have its cover program written in Lisp? NeonMerlin 21:35, 26 February 2009 (UTC)

There are a number of viruses for AutoCAD, written in its AutoLISP language. 87.112.17.229 (talk) 21:51, 26 February 2009 (UTC)

C standard

Does

!! some_int

always evaluate to either 0 or 1? --194.197.235.29 (talk) 23:02, 26 February 2009 (UTC)

No. Try it yourself. Try some_int=0 and some_int=1. You should get different results. -- kainaw™ 23:07, 26 February 2009 (UTC)

This reasonably formal definition would say yes. I don't know if an absolutely formal definition of C is available online. 87.112.17.229 (talk) 23:08, 26 February 2009 (UTC)

I read the question as "will !! some_int always be a 0 or will !! some_int always be a 1?" It will be a 0 if some_int is 0. It will be a 1 is some_int is not zero. Therefore, it will neither always be 0 or always be 1. -- kainaw™ 23:16, 26 February 2009 (UTC)

Yeah, I think he's asking the rather deep question whether standard guarantees that !!3==1 and !!-4435==1 (and thus that some clever compiler optimisation won't turn !!-4435 into -4435 instead). I'm almost certain that's true, but you can bet that when they were writing the standard someone lobbied for !0 to simply be "any integer that isn't 0". 87.112.17.229 (talk) 23:23, 26 February 2009 (UTC)

According to the C99 standard + TC2, section 6.5.3.3.5 (page 79, on page 91 of pdf), ! will return 0 if its argument is non-zero, and 1 if its argument is zero. So yes. —Preceding unsigned comment added by 131.179.32.100 (talk) 01:37, 27 February 2009 (UTC)

Ok, thank you very much. My English can be a bit good sometimes, I meant what 87.112.* wrote above. --194.197.235.29 (talk) 01:57, 27 February 2009 (UTC)

The standard does _not_ guarantee, however, that a 1 will ever exist in memory if you don't use it. That's below the level of abstraction it is concerned with (For example, if(!!x) { ... } may compile to the exact same code as if(x) { ... } and never convert x to a 1-or-0 value.) But if you assign y=!!x then y will be 1 or 0. --Random832 (contribs) 16:49, 3 March 2009 (UTC)