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January 22

Timer limit on Digital video recorders

I recently bought a new Digital video recorder and was somewhat disappointed to find that I can only set the timer to a maximum of one month ahead, even the daily/weekly repeat function auto-cancels after a month. Now if say I go on a three month holiday I can only record my favourite weekly show for the first month and then will miss the rest. With my old VHS I could set the timer for up to a year ahead and the repeat function would operate indefinitely even for years as long as you kept tapes up to it. Is this limit typical for Digital video recorders or just the Panasonic one I bought and if typical why have the manufacturers done it? Is it just pressure from the studios to limit recording functionality or what? Are there any 'cracks' that allows me to use my DVR timer more like my old VHS? Dob in a Nerd (talk) 04:27, 22 January 2012 (UTC)

You forgot to mention which one you have. Ask a friend or neighbour to configure it for you when you are on a vacation that lasts longer than a month, the same person that waters your plants and collects your mail. Download your favorite TV-shows, or buy them on DVD. Von Restorff (talk) 04:32, 22 January 2012 (UTC)

That's odd. I never had a problem with my TiVo auto-recording a program for months or years repeatedly. Which DVR do you have? Knowing that would help folks give you better answers. RudolfRed (talk) 04:43, 22 January 2012 (UTC)

As I said it's a Panasonic it's combined DVR/DVD recorder I think it's probably the DMR-XW385GLK but I'm not at home at the moment so can't double check. The shows I want to record are more things like live sports so I can't buy them on DVD or really even download later and I don't think my 80 year old neighbour will really be up to reprogramming my DVR for me. Dob in a Nerd (talk) 06:32, 22 January 2012 (UTC)

This would be the one [1] thanks. Dob in a Nerd (talk) 06:38, 22 January 2012 (UTC)

If you live in a deserted place with just 1 neighbour, two zombie sportsteams, and an evil ghost who broadcasts local television and your friends and family are unable to receive the same television signal and unable to visit you because they live in the nearest town (which is on another continent thousands of miles away) then the easiest solution would probably be to make a big signal fire and when they come to rescue you ask them if they would be so kind to write down your GPS coordinates, go back to the civilized part of the world, go to a museum to get a VCR and some videotapes and put them in a big crate and attach a parachute to that and then throw it out of a plane that is flying over your location. I am not sure if that would be really useful considering the fact that it is impossible to record many hours of video on a videotape, but maybe you just want to record one or two games during your holiday that lasts multiple months. For me personally it is kind of hard to get excited over a sportingsevent that happened months ago, but I am kinda weird. I am assuming you do not have an internetconnection at home, if you do you could build a robot so that it would be possible to program your DVR remotely over the internet. I am also assuming your holiday-destination does not have an internet connection otherwise you could've watched the game with live streaming, or download it via torrent or usenet. I am also assuming your friends and family are unable to receive the same television broadcasts and/or do not own and cannot afford a VCR or DVR and contacting the ghost is not an option because he is evil and the zombies want to eat your brain. Von Restorff (talk) 07:16, 22 January 2012 (UTC)

Thanks for your helpful reply and yes I am being sarcastic. I do live in a remote outback location and my family do live many hundreds of kilometres away and the stuff I want to record is on satellite pay-tv that few other people I know get and for your information I am travelling internationally to attend the sporting event which is why I also want to record it and the lead up events, which I will probably miss as I do things other than watch TV or streaming internet while travelling but I may wish to view the broadcasts later if I so choose, so your answer shows a hell of a lot of ignorance. And also for your information none of that matters or is any of your business as it is not relevant to the actual question that I asked which you obviously know nothing about and are unable to help with. So if you'd like to shut up maybe I can get an answer from someone with a mental age greater than ten who has something intelligent to say. Dob in a Nerd (talk) 08:04, 22 January 2012 (UTC)

Thanks for your kind reply; I love you too. Do you know Eric Hoffer's famous quote about rudeness? As you may have noticed there was quite a bit of useful advice hidden in my response. Contacting the evil ghost sattelite pay-tv channel may be a good option, or buying a VCR or a DVR with the required functionality. Maybe it is cheaper to pay the sattelite TV channel access fee for one of your friends in the area. You could even try recording the TV-signal on your computer (I think this is the best long-term solution in your case)! Much love, Von Restorff 08:32, 22 January 2012 (UTC)

Let me just reset this question please as Mr Restorff has taken great joy in leading this post astray with childish behaviour. I originally asked some specific things none of which have been addressed except for briefly by RudolfRed, namely: Is this limit typical for Digital video recorders or just the Panasonic one I bought and if typical why have the manufacturers done it? Is it just pressure from the studios to limit recording functionality or what? Are there any 'cracks' that allows me to use my DVR timer more like my old VHS? If any knowledgeable Wikipedia members can provide any information on those I would be happy to hear it. Dob in a Nerd (talk) 12:25, 22 January 2012 (UTC)

A good DVR will have a guide meaning it can record based on programme not time. Nil Einne (talk) 12:53, 22 January 2012 (UTC)

That's a good point and is accurate except for the problem being that the satellite signal has to go through the pay-tv decoder and the only way to input this signal from the decoder to the DVR is via an A/V input. Since it's simply inputting to the DVR as a straight A/V signal there is therefore no electronic program guide associated with it and I have to manually set the timer which gets back to the original problem being that manually setting the timer is restricted to only a month ahead. Dob in a Nerd (talk) 14:10, 22 January 2012 (UTC)

That doesn't necessarily matter. Many DVRs get their guides from the internet either from free sources or from some subscription source. The DVR can be controlled with an IR blaster to change channel. This is definitely possible with a PC based DVR or a HTPC like MediaPortal, MythTV or even the crappy (IMO) Windows Media Centre. Guides for pay TV are generally less common but often there's still some options. (It's not that hard to set up here in NZ if you know what you're doing, I know since I've done it.)

You didn't mention where you live, but if it's Australia it sounds like OzTiVo supply guide data for FoxTel. No idea about other pay TV providers. (As you may known the official TiVo in Australia has no IR blaster nor any support from recording from a YPbPr, S-video or composite.) Shepherd Guide [2] also supports FoxTel although no other pay TV providers. To be fair these community or random person guides can be a bit fiddly, particularly when your source of guide data dies for whatever reason [3] but IMO it's worth the effort rather then trying to cope with timer only recording. Scraping may also be possible although with the precendent from the IceTV case, I'm not sure if FoxTel will bother to target EPG providers, in which case scraping is likely to be more fiddly.

If you want to avoid the internet because it's unreliable where you live or whatever, it sounds like EPGCollector support the OpenTV that FoxTel uses, although in that case you will to set up a satellite receiver on the PC DVR to collect the EPG. (You could also use it for FTA satellite channels.) This in itself shouldn't add much cost, a cheap Chinese USB satellite tuner from eBay or whatever is under US$25 IIRC but I'm not sure whether you'll have problems due to the split satellite stream and conflicts with the STB. (Presuming your LNB doesn't have multiple independent outputs.)

Also while this doesn't help much, I believe in Australia, as in most countries without legal requirements, there's little support for any sort of hardware Conditional-access module from most pay TV providers so you have no choice but to use the pay TV manufacturers DVR unless you want to run the risk of soft CAMs which even if they support your provider, can break for a long time when the provider finds a way to stop them. As for example happened with FoxTel in Australia. (I first read of this several months ago and a quick check shows it's still broken. Oh and of course the legality of soft CAMs is also not tested hence why I'm not providing a link for this last point although I personally have my doubts they can go after you if you aren't doing something dodgy like card sharing.) Anyway back to my main point, considering this, if you are in Australia, perhaps you may want to ask your government or MP whether they think it's a good thing the pay TV channels can shut out other DVR providers in this way, particularly given the advantages it gives them in areas like TV on demand. (Here in NZ, given that the government doesn't care that our pay TV provider looks like it it's going to become a monopoly which will slowly suck the lifeblood out of free TV, there's little point.)

BTW in terms of your earlier questions, I don't see any reason why TV companies would bother to try and restrict the timer in that way. They're much more likely to demand restrictions on skippind ads Freeview (Australia)#Digital video recorder restrictions and also on copying and accessing content. It seems much more likely it's something they implemented without much thinking because they didn't think it was going to be an issue.

It does seem a fairly common limited for the standalone combo DVR/DVD recorders, particularly Panasonic ones (a search for Panasonic DVR "month in advance" shows many model manuals mention this) but also others including very old DVD only recorders [4] [5] [6] [7] [8] [9] [10]. Just do a search for DVR (or DVD) "month in advance". Many of these have a similar limit number of events, 8 for very old ones, 16 for slightly more recent ones and 32 for current ones (although I did find some 12 [11] [12] and one 7 [13] and one 20 [14] and one 36 [15]).

Anyway the fact that it's been going on since 1999 makes me think either you're right and for some reason DVR/DVD recorder (and DVD recorder/VCR before them) manufacturers were forced by outside parties to limit their devices in such a way. Or I expect more likely, they're all using a related UI and probably the software under it and no one bothered to modify the timer functionality much except to increase the number of programmes supported. Perhaps the device doesn't actually store the date of the recording, but only how many days from now and updates it every day, and they limited that to 30. Another reason of course to like PC based PVRs, even if you don't use an IR blaster for pay TV like I didn't in 2003? when I first got one, you don't have to put up with such stupid limitations.

Nil Einne (talk) 17:42, 22 January 2012 (UTC)

Thank you very much for your thoughtful and detailed answer Nil Einne it certainly gives me a lot to consider, you seem to be very knowledgeable in this area and have brought up many options I did not know about such as the IR blasters and much else so perhaps it is your line of work. Unfortunately I am on the Austar service not Foxtel so my options are much more limited with EPGs and the like and to add to the problem my free to air service is via the Viewer Access Satellite Television system which also seems to be limited in a similar way with a CAM smartcard in the decoder and I have not yet worked out how to feed them both into my DVR at the same time as it only has one AV input. I think there might be some way to use the VAST system with a DVR and their standard EPG and perhaps with a connection other than the AV output/input but I have not looked into it in enough detail yet but at this stage I was mainly looking at the Austar problem without wanting to pay extra for their custom DVR solution. I suppose I haven't really worried all that much in the past because I actually only record one or two programs a week other than the occasional instant recordings you do when the phone rings or nature calls but that just needs access to a record button, but that all means I don't really want to spend too much effort or money on a variety of solutions. About the timer recordings it is strange because my old Panasonic VHS recorder can be set for up to a year ahead and the repeat function simply continues indefinitely so with all the links you provided above it seems they have intentionally removed functionality from the digital recorders timer function I don't know why. Well thank you again that is the sort of knowledgeable discussion I was hoping to get here not the rude reply I received earlier. Perhaps if I have any other questions I could ask you directly on your own talkpage rather than come here and be insulted? Thanks Dob in a Nerd (talk) 02:57, 24 January 2012 (UTC)

In reality you are the one who was rude and tried to insult me, not the other way around. You failed, I do not feel insulted, because I looked at your contributions. Do you know Eric Hoffer's famous quote about rudeness? Von Restorff (talk) 03:16, 24 January 2012 (UTC)

New monitor flickers only while gaming

I recently upgraded to a 1080p LCD monitor (I'd been using a 1280x1024 before). Since then, I've noticed a horizontal flicker where lines become brighter and dimmer. This seems to happen only while playing games or for short periods afterward, so at first I suspected it was a video card artifact, but it doesn't show up in screenshots. Could it be a power issue (e.g. the video card undervolting the output when the GPU and cooling are at full load)? I'm using a VGA cable, with an HDMI adapter at the card end. The refresh rate is 60 Hz (the old monitor was 75 Hz). The new monitor has no option to degauss it manually. NeonMerlin 07:37, 22 January 2012 (UTC)

LCD monitors don't have a degauss option. What you're seeing is the monitor upscaling, and possible deinterlacing of the signal from your games. Each game usually requires setting the screen resolution to match your monitor's. If a game has it's resolution set to "XXXi" (e.g. 720i), it means it sends an interlaced signal, which causes the line-flicker you describe. If your videocard can hack it, set your game(s) to output 1080p. — Edokter (talk) — 12:00, 22 January 2012 (UTC)

I don't think this is a native resolution problem. My aged video card also will cause individual lines to flicker at certain resolutions. The effect is intermittent, which certainly says "hardware problem, get another video card" to me, in my case at least. When my system boots, even the text on the POST screen has problems where garbagey text characters are in place instead of many of the normal characters. Comet Tuttle (talk) 19:04, 22 January 2012 (UTC)

Since the OP only started seeing the problem since the new monitor, I think we can rule out a videocard defect. Simple enough to test by reconnecting the old monitor. — Edokter (talk) — 11:45, 23 January 2012 (UTC)

Try enabling V-sync. I think what you're experiencing is Screen tearing. -- Obsidi♠n Soul 02:40, 23 January 2012 (UTC)

I've had that problem on my Dell. Amazingly, playing with the contrast setting fixed the problem! Sandman30s (talk) 12:06, 23 January 2012 (UTC)

In World of Warcraft, I fixed it by changing the mode from Windowed (Fullscreen) to Fullscreen. (In Windowed (Fullscreen), it was sometimes rendering 61 fps even though vsync was on.) What are these modes usually called in non-Blizzard games? NeonMerlin 04:04, 24 January 2012 (UTC)

How to speed up the floppy drive in VICE?

I've now got OpenCBM working with ZoomFloppy, and have been successfully able to transfer my old Commodore 64 disks to my Linux PC as D64 files. But when I load these D64 files into VICE, it looks like it is faithfully emulating the notoriously slow Commodore 1541 drive, and I have to wait twenty or thirty minutes to load a game consisting of less than 100 kilobytes. Modern PCs should be able to do this under a second. Is there a way to speed up the emulated floppy drive in VICE while still keeping the speed of the emulation otherwise faithful? JIP | Talk 11:02, 22 January 2012 (UTC)

Try this, use warp. Von Restorff (talk) 12:02, 22 January 2012 (UTC)

I don't think that's what I want. I only want to speed up the floppy disk emulation, while keeping the actual emulated Commodore 64 at the speed of a real Commodore 64. JIP | Talk 12:31, 22 January 2012 (UTC)

Whatever happens with your speed, congratulations on transferring 30 year old floppy disks! I am surprised the magnetic coating was intact. That is delightful! Comet Tuttle (talk) 19:02, 22 January 2012 (UTC)

Well, not all of them quite made it. The most were intact, but I think one-tenth to one-fifth had minor read errors, and a couple refused to work all together. I haven't had the time to test all the games, but some of the resulting D64 files crash VICE when opened, so I guess they didn't manage to transfer successfully. I don't have a real Commodore 64 any more, so I can't try to see whether the disks still work when accessed from a real Commodore 64. JIP | Talk 19:06, 22 January 2012 (UTC)

Well, in that case, sorry to hear it. I sympathize; I remember copying floppies with two of those things hooked up together, and I do think it was an hour to copy each disk. Comet Tuttle (talk) 19:08, 22 January 2012 (UTC)

Yes, I remember that it took almost an hour to copy a disk with a real Commodore 64. With the ZoomFloppy, it only took about five minutes. (Which is still a long time, when you're accustomed to disk transfers taking a couple of seconds.) I've tested a few games so far. Bounty Bob Strikes Back and Wizball work OK. Spelunker starts OK, but I've so far been unable to actually play it. Crystals of Zong crashed as soon as it started. I haven't had the time to test any more. JIP | Talk 19:13, 22 January 2012 (UTC)

Did you try the -truedrive command line option? Von Restorff (talk) 20:33, 22 January 2012 (UTC)

I'm sure you know this already - but why go through the pain of transferring disks when these images are available for download and not illegal to use since you have the originals? Also, there are many other great emulators for C64, at least for PC anyway, which load images immediately. Now that was a brilliant era - I miss those good old days. Sandman30s (talk) 12:04, 23 January 2012 (UTC)

Subtraction?

On my AppleMac 'Numbers' programme I have a spread sheet where I am taking from 'A' (the larger sum), a smaller sum 'B'. The resultant balance 'C' is preceded by a minus (-) sign, why should this be please? It is confusing because 'C is a quantity value, the result of taking 'B' from 'A', it is an actual value, not of itself minus anything. Any advice will be welcome please! --85.211.142.228 (talk) 11:56, 22 January 2012 (UTC)

If your taking a larger number from a smaller number that will leave you with a Negative number which is what the minus sign means in your program. Dob in a Nerd (talk) 12:16, 22 January 2012 (UTC)

Please reread the question Dob in a Nerd. Von Restorff (talk) 12:29, 22 January 2012 (UTC)

Your terminology is somewhat confusing. Could you give us more concrete information (the numbers and the equation involved)? Paul (Stansifer) 12:33, 22 January 2012 (UTC)

Paul, herewith the numbers 12,684.86 from which is deducted 18489.12 and I am getting the result "-5804.26" (and I am further dividing this by 12 and getting "-483.69").--85.211.142.228 (talk) 12:48, 22 January 2012 (UTC)

Well, that is all correct. 12,684.86 is smaller than 18489.12, so the difference is a negative number. You may be confused because one of the numbers is written with a comma? For a simpler example, consider 13-18, which gives -5. --Stephan Schulz (talk) 13:04, 22 January 2012 (UTC)

Well, no wonder that this ageing, uneducated man is confused, thanks for the answers though.--85.211.142.228 (talk) 13:30, 22 January 2012 (UTC)

You're welcome. I suspected that's what you must have been doing despite how you originally wrote the question so glad we could help. Dob in a Nerd (talk) 13:59, 22 January 2012 (UTC)

iPad bookmarks

Resolved

Can anyone tell me how to 'bookmark' web pages on my iPad2 please? Thanks in anticipation.--85.211.142.228 (talk) 20:34, 22 January 2012 (UTC)

here Von Restorff (talk) 20:44, 22 January 2012 (UTC)

Brilliant, just what I needed, thanks--85.211.142.228 (talk) 20:58, 22 January 2012 (UTC)

January 23

Sharing big files

How can I share legal files with people? I need a service without silly ads. — Preceding unsigned comment added by 88.9.209.157 (talk) 00:01, 23 January 2012 (UTC)

How big? Dropbox (minimum 2GB), SugarSync (5GB), Windows Live SkyDrive (25GB). See also comparison of file hosting services and comparison of online backup services. If the files are really big and other people are willing to help spread them you may want to use torrent. Von Restorff (talk) 00:05, 23 January 2012 (UTC)

SkyDrive does not allow for more than 50 MB, which is kind of too little. SugarSync is not free and Dropbox seems to require to install some software. Are there more options? BTW, it could be with ads, but not silly ads (like find a Russian bride or 18-yo wants to meet you). 88.9.209.157 (talk) 00:18, 23 January 2012 (UTC)

If you do not want to install software and a 2GB maximum is acceptable then you can use something like wetransfer.com. SugarSync has a free 5GB plan, but they try to hide it a bit. Go here. It says: "5 GB Free Plan - Not a trial but a free account with no credit cards and no monthly payment" (maybe you need to scroll down a bit). I am not 100% sure but it is likely you will need to install some software. No need to worry about that, it is not malware, and once you've uploaded the files you can uninstall the software. Another option with 5GB free is Ubuntu One but their Windows client sucks imho. Von Restorff (talk) 00:34, 23 January 2012 (UTC)

Our article says 100 MB although that's still very small. Nil Einne (talk) 13:33, 23 January 2012 (UTC)

Sendoid is pretty convenient, but I wouldn't use it for really large files. Most instant messaging clients and protocols support file transfer, too. ¦ Reisio (talk) 01:05, 23 January 2012 (UTC)

Sendoid's web interface limits total transfer size based on the resource availability of your local machine. This tends to be somewhere between 600MB and 1gb. Von Restorff (talk) 01:11, 23 January 2012 (UTC)

DropBox is pretty convenient. You can use it without installing the software. It also has a web interface. --Mr.98 (talk) 01:08, 23 January 2012 (UTC)

I <3 DB. I am not a fan of uploading big files via the website, but it certainly is possible. Von Restorff (talk) 01:09, 23 January 2012 (UTC)

What about the original File Transfer Protocol and its free!--Aspro (talk) 01:30, 23 January 2012 (UTC)

Oh, yeah, I almost forgot that still existed A couple of years ago I had a FTP server running at home but I replaced it with the combination of torrents with webseeds and Dropbox. Von Restorff (talk) 01:39, 23 January 2012 (UTC)

What would you do, without us old fogies? --Aspro (talk) 01:55, 23 January 2012 (UTC)

Google Docs doesn't require special software although only gives you 1GB for free per account. There is effectively no file size limit for files Google Docs doesn't intepret since the limit is 10GB [16]. If you want more options, I suggest you check out the article linked to by VR since I'm pretty sure it includes most of what's been discussed and more. Nil Einne (talk) 13:33, 23 January 2012 (UTC)

Files that you upload but don’t convert to Google Docs format can be up to 10GB each. This upload limit is larger than the free storage space given to each Google Docs user. Every user is given 1GB of free storage space for files, and can purchase additional Google Docs storage to upload larger files. Von Restorff (talk) 17:31, 23 January 2012 (UTC)

Isn't that what I said? Well I didn't specifically mention that you can purchase more space, but I thought that would be obvious. Nil Einne (talk) 23:29, 23 January 2012 (UTC)

Now that you mention it, yes, it is. Meth is a hell of a drug. Von Restorff (talk) 01:16, 24 January 2012 (UTC)

seizing websites: how does it technically work?

In light of the Megaupload incident, there is something I've always wondered: just how exactly does the U.S. government seize domain names?

I'm under the impression that this is done through court orders, which would require the domain registrars to hand over the domain names to the appropriate agency. It would be natural to think that this would take some time because the court has to deliver the order to a registrar's legal department, which would then forward the instructions to the technical department. Yet the shutdowns usually happen pretty quickly. Is it safe to assume that registrars have a very short timeframe in which to comply or face penalties? Or is there another means for the .gov to shut down websites?

This brings me to my second question: a domain name merely resolves to an IP address. However, very few websites have come back online quickly under a different domain after being shut down (Megaupload certainly doesn't seem to be one of them). In this case, does the government do anything other than seize a domain name, such as ordering the hosting provider to suspend access to the actual resources? I do know that authorities can seize the physical servers on which an infringing website is located, but this isn't always the case, especially for people that use overseas servers. --Ixfd64 (talk) 01:52, 23 January 2012 (UTC)

Most large companies have on-staff legal departments that receive government and court instructions and know how to respond to them (not all such proceedings are necessarily mandatory, and a company may wish to appeal). If those people believe their company should act, they have access to internal processes and people to get stuff done quickly. Generally a court will require them to act with reasonable diligence - if they do so in a way that's consistent with how they'd handle their own urgent business then a court will likely be satisfied with that. As for a shutdown - indeed, seizing only a domain allows the service to continue under another domain (and some things like p2p networks don't rely on DNS to work). They'll want the servers themselves physically seized, because these have evidence of the suspect's alleged wrongdoings (e.g. logs, email traffic) and if a suspect knew he was under investigation he'd be likely to wipe his whole system. So for maximum effectiveness (bearing in mind they want a solid prosecution, not just to shut down a given service and have a workalike pop up a few days later) law enforcement wants to coordinate its efforts into one swift strike. Doing that, particularly over cross-jurisdictional and cross-country boundaries is difficult and time consuming (and will have required other parties to consult their own legal teams). The MegaUpload raids will have been weeks in the planning; they didn't just brainstorm this idea one day and execute it the next. While this kind of thing is unusual for technology stuff, such synchronised operations are par for the course for organised crime, drugs, people smuggling, and terrorism cases. 87.115.127.51 (talk) 02:27, 23 January 2012 (UTC)

The process is also something of a freight-train; once they've got it started, it's hard to stop. Lots of people in the US and NZ authorities (and probably other jurisdictions like HK) will have been involved in the logistics, and once they've fixed a date they'll have essentially "booked" the time of police resources like officers' time, helicopters. The co-incidence of the MegaUpload raids and the planned voting dates for PIPA and SOPA seems to uncanny to ignore- but even with those kicked seemingly into the long grass, the raids would either have to go ahead anyway or news of their cancellation would come out (too many rank-and-file people knew stuff by then). 87.115.127.51 (talk) 02:33, 23 January 2012 (UTC)

Thanks for the detailed explanation, 87.115.127.51. That makes a lot of sense. Cheers! --Ixfd64 (talk) 02:48, 23 January 2012 (UTC)

As two additional points, the date of the raids was selected for a reason. There was a birthday party for one of the accused planned for the time, which meant several of the accused would be present. [17]. Also while the US government took over the domain fairly fast, it wasn't as soon as the raids happened. For several hours Megaupload was unavailable, generally believed to be because their US based servers were seized. It was only later that the seizure notice came up. Nil Einne (talk) 14:10, 23 January 2012 (UTC)

Hot CPU?

I run a CPU intensive task in the background all of the time on an i7. The CPU temperature is about 70C, which SpeedFan says is way too hot. Is this bad for the CPU? Bubba73 ^{You talkin' to me?} 04:49, 23 January 2012 (UTC)

PS, Speccy says that it is 75C and still in the OK range. Bubba73 ^{You talkin' to me?} 04:54, 23 January 2012 (UTC)

Pushing it I reckon. See http://communities.intel.com/thread/21563 for other opinions (if you like). CPU cooling systems exist for good reason. fredgandt 05:09, 23 January 2012 (UTC)

I'd say you need to be in the 30C to 50C range. Things like CoolerMaster get you there. High temperatures not only lower the lifetime of your components but can cause random problems like hanging etc. Sandman30s (talk) 11:56, 23 January 2012 (UTC)

Since I posted that, I found some blog that said that 72.5C is the recommended max temp for my CPU. Speccy isn't bothered by it being 74C. The motherboard and GPU are 45 to 47C - only the CPU is hot. Bubba73 ^{You talkin' to me?} 17:55, 23 January 2012 (UTC)

Are you sure that the sensors are correctly labeled? If your CPU temp reaches 70-75 degrees it is time to clean the dust, doublecheck if the fans are working correctly and buy extra cooling stuff, but I think it is the GPU. Von Restorff (talk) 21:07, 23 January 2012 (UTC)

I am not sure they are labeled correctly, but that is what both Speccy and SpeedFan say. This is a quad-core CPU with 100% CPU use. Bubba73 ^{You talkin' to me?} 23:30, 23 January 2012 (UTC)

My guess would be that the sensor that reports the highest temperature after playing a modern game like Battlefield 3 for a while is measuring the GPU's temperature. Von Restorff (talk) 23:54, 23 January 2012 (UTC)

I don't play any such games, but actually I'm pretty sure that it is labeled correctly because if I turn off the program that is using the CPU heavily, the CPU temperature quickly drops to about 51C and in a few more seconds, to around 48C, according to Speccy. Bubba73 ^{You talkin' to me?}

75 C seems high to me, even for a high-end i7 on air cooling. What's the TDP? I have a substantially overclocked i5-2500k (TDP 95 W) with a basic closed-loop water cooler (Corsair H50) and it runs about 58-60 C at 100% load. Start by cleaning the dust out of the radiator, checking to make sure that the cooler fan operates at full speed, and checking the overall airflow inside the case. (I suspect that you are having problems with the airflow - 45 C for a motherboard is also high.) Add a couple of 120mm fans. Try keeping the case open and see if that helps.--Itinerant1 (talk) 06:04, 25 January 2012 (UTC)

I don't know what TDP is, but I'll check for dust and check the airflow. Bubba73 ^{You talkin' to me?} 02:11, 28 January 2012 (UTC)

Referrer spam possible in non-bot traffic?

According to this article, the best way to respond to referrer spam in Google Analytics is to filter out traffic with known spammy referrers. This makes sense to me if the traffic is all generated by bots, since it doesn't indicate actual readership, but is it possible that a visitor may have malware that simply spoofs the referrer header on their legitimate traffic (since that would be harder to detect on their firewall or modem lights, compared to creating traffic when they weren't browsing)? NeonMerlin 08:59, 23 January 2012 (UTC)

It's certainly possible in theory.. but if malware was at that level of control of your machine, why wouldn't they just redirect your browser traffic, forcing you to visit the sites they sponsor, instead of spoofing referrers which might only give perhaps a 1-in-a-1000 chance of someone looking through the referrer logs following them. Unilynx (talk) 18:53, 23 January 2012 (UTC)

The idea behind referrer spam is not that sysadmins will visit the site, but that the logs will get posted somewhere or be publicly available, and thus boost pagerank and things like that. --Mr.98 (talk) 19:56, 23 January 2012 (UTC)

My experience with referrer spam is that Google Analytics automatically filters out 99% of it. (I've come to this conclusion comparing my Google Analytics listings from my raw server statistics; the latter have so much referrer spam that it's just nearly impossible to sort out the signal from the noise, while the Google Analytics has removed almost all of those.) That doesn't really answer the question, though, other than to suspect that Google already has clever enough algorithms in place that doing it manually isn't worth the time. It's possible that legit users could have wacko referrers but that's not the current situation at all, where the vast number of referrer spammers are clearly bots. --Mr.98 (talk) 19:56, 23 January 2012 (UTC)

"expert" user-generated content

Wikipedia's own article on "user-generated content" doesn't really deal with one species that I often encountered a few months ago but (whether because I'm googling for different subjects or because Google has downranked the sites) I seldom encounter these days -- websites that invite individuals to post their own factual (?) and helpful (?) complete articles on particular subjects. (Unlike Wikipedia, individual pages don't invite collaboration or improvement by others.) Some of the content on these sites looks at least moderately good at first glance, and the sites tend to have sober designs, presumably in the hope of both attracting potential writers and impressing potential readers.

(I'd also often encounter links to these sites as would-be references in Wikipedia articles, and would zap them [as unreliable] when I found them; I haven't seen such links recently [whether because I spend less time looking for them or because most are now in the spam blacklist].)

I have a fleeting and "academic" interest in such websites. Question, then: Is there a name for this kind of website? If not particularly (as I'd guess), can somebody jog my memory with the domain names of a few examples? (Better not attempt to link to them.) -- Hoary (talk) 09:21, 23 January 2012 (UTC)

I presume you mean things such as eHow and Associated Content. My experience with both is their content is generally not particularly good. I have occasionally provided them as refs on the RD, either because there was nothing better or as an additional ref but often don't bother to even read them when I come across them in searches. Both are blacklisted on wikipedia. I'm not surprised because as writers are usually paid at least partially based on how many hits they get (or I think more accurately advertising revenue from their article), there's a strong incentive to spam from people who are the kinds who have not much to lose. And they are unlikely to have much legitimate use since they aren't likely to be considered RS. Nil Einne (talk) 13:45, 23 January 2012 (UTC)

P.S. Other examples would be About.com, HubPages, Helium.com and Google Knol (which is destined for death) Nil Einne (talk) 14:05, 23 January 2012 (UTC)

Yes! Helium.com was one of them. (I did know about About.com, but this site is an odd mixture indeed, containing worthwhile material among the dross. And the dross includes a lot of stuff by people who are identified and who presumably were paid.)

Armed with the name helium.com, I soon found writing.com (for "literature" only?), suite101.com, voices.yahoo.com (previously associatedcontent.com), ... Ugh.

(Fear not: I have no intention of pressing for recognition of websites such as helium.com as reliable sources. And if somebody were to point out that this or that page within it was of excellent quality, this might surprise me but it wouldn't change my opinion. After all, the occasional undergraduate term paper that's posted to the web is of excellent quality, but we don't accept even masters' theses, and nor should we.) -- Hoary (talk) 02:20, 24 January 2012 (UTC)

Some files missing - TestDisk didn't help (but then it did)

Resolved

I use a standalone hd-recorder to record from tv, for which I use an external hd. When I unplugged the hd during a recording to view on my computer (Linux Mint), all the files (and directories) in the directory to which it recorded were missing (on my old hd this was never a problem). Recordings in another directory on the same partition were still there. When I plugged it back in the recorder that did show some recordings, but only recent ones (not the ones I had already renamed on my computer).
So I analysed it with TestDisk, which reported

ntfs_device_testdisk_io_ioctl() unimplemented

NTFS Volume is dirty.

'List files' showed all the files. Not really knowing what I was doing, I tried 'Write' (and reboot) and when that didn't help 'Load backup', which didn't help either. So I tried Disk Utility's 'check filesystem', which reported 'File system is clean'. But TestDisk still reports it to be dirty. So now I'm stuck.
I used PhotoRec successfully before, but this is a 2 TB partition, which is going to take forever. And I'd have to buy another hd of that size to write to.
Any idea what I might try? DirkvdM (talk) 14:43, 23 January 2012 (UTC)

Aha, that annoying "dirty bit"-problem. Sorry, I am a Wind0wsn00b, but I would do something like this. Von Restorff (talk) 15:44, 23 January 2012 (UTC)

Does Linux have something like chkdsk? I don't have msWindows. (Btw, I've read several warnings not to use chkdsk, because it can really screw things up.) DirkvdM (talk) 18:35, 23 January 2012 (UTC)

Oh, and before anyone asks, I use NTFS because that's what the recorder wants. DirkvdM (talk) 18:36, 23 January 2012 (UTC)

Make a backup! fsck is a chkdsk equivalent. Or install the ntfsprogs package and use the tool in that. Von Restorff (talk) 20:54, 23 January 2012 (UTC)

Ntfsprogs is already installed. I ran ntfsfix (after unmounting the partition), which says "Failed to startup volume. Permission denied." and then "Volume is corrupt. You should run chkdsk." But I don't have msWindows. So I tried fsck, but I get "fsck.ntfs: not found". Which I already anticipated - it's only for Linux/Unix filesystems, I assume. DirkvdM (talk) 09:48, 24 January 2012 (UTC)

Well, get a Windows CD/DVD (in a legal or illegal way), and use it as a livecd so you do not have to install it. Von Restorff (talk) 10:04, 24 January 2012 (UTC)

Hold on. TestDisk does help!

Before trying your suggestion I wanted to make a complete overview of all the files, using TestDisk, when I coincidentally noticed an option 'copy'. So I tried that and indeed it copied the file (or directory). I have now copied everything and all seems to be well. It worked at normal copying speed.

For a complete description: open a console, go to the dir where you want to copy the 'lost' files to (and where the log file will be put), and type 'testdisk'. Then (in my case) Create new log file > give root password > select partition > Intel partition table type (the default is usually correct) > Analyse > Quick search > Vista? ('No' in my case). And then type 'p' to browse the partition with the arrow keys. Select any file or directory you want to copy (works one at a time) and press 'c'.

I don't know if any of the earlier actions ('Write' and "Load backup') were necessary for this to work, but they don't seem to have hurt. :) DirkvdM (talk) 11:13, 26 January 2012 (UTC)

Oh lol, well that probably saved you some time. Von Restorff (talk) 12:24, 27 January 2012 (UTC)

service providers and passwords

Do mail service providers like Gmail or Yahoo save passwords in retrievable form? Do they handover passwords to law enforcing agencies? --117.253.198.143 (talk) 16:36, 23 January 2012 (UTC)

Would you consider a salted hash to be retrievable? It is more likely they just make a copy of the contents of the account. Von Restorff (talk) 16:46, 23 January 2012 (UTC)

One would have to know how those services store passwords (and it is unlikely that they would reveal specifics) but 99% of the time websites do not store the actual password for security purposes. Rather, when the user creates the account the service generates a hash of the password, often salted. When the user tries to log in later, the same hashing and salting function is used on the password entered, and the two hashes are compared. By doing this, the service does not know your actual password. TheGrimme (talk) 17:19, 23 January 2012 (UTC)

And just to follow up on your question, while these services might not give your password to law enforcement agencies, they can easily provide either alternative access or an exported view of your account. Email services will likely cooporate with law enforcement if the agency has a subpoena. TheGrimme (talk) 17:24, 23 January 2012 (UTC)

Bear in mind the very important distinction between two very different things:

• An account, like Google Mail, that uses secure transport, such as https, to provide cryptographically-secure access to a Google-owned server that stores your unencrypted data
• A server that encrypts your user-data (or, a user-side client that encrypts the data so that the server cannot meaningfully interpret it).

When you connect to GMail over a secure channel (like HTTPS or IMAP/TLS), your use of industrial-strength cryptography "guarantees" only one thing: You And Google, but nobody else, can both read the private contents of your emails. No third-party can intercept the data while it is in transit.

Google still has totally unimpeded access to your data. If you are uncomfortable with this, you have several options:

• Manually encrypt your data for end-to-end transmission, before you enter it into the email client, so that the server never sees your private data in plain-text. This can be fairly inconvenient, but it's much more secure. At the same time, this only encrypts the data, but the mail headers (including the recipients' addresses) must still be readable by the server. Essentially, this means that whoever received your email will receive "junk data" and must have the expertise, willingness, and software tools, to decrypt the contents back to human-readable form.
• Avoid using Google (or Hotmail, or any other untrusted service-provider). If you don't own and operate the mail server, you don't know how the owner/operator is using your data. Even still, unless you own and operate every element of the network between you and your destination, even encrypted traffic is still subject to traffic analysis; so you should be sure to send as much white-noise as possible. Nimur (talk) 19:40, 23 January 2012 (UTC)

Simple test: if a site lets you reset your password after you forget it, that means the data isn't stored in a securely-encrypted fashion. --Colapeninsula (talk) 11:03, 24 January 2012 (UTC)

Shouldn't that be: If a site lets you recover your current password? If a site has you reset the password to a new value, that generally means they can't actually retrieve the existing password, and is thus hashed. 66.46.213.4 (talk) 18:01, 24 January 2012 (UTC)

No, ColaPeninsula's example was correct as it was originally written. If the contents were encrypted, it would not make sense to "set a new password." Creating a new password would be irrelevant for accessing the encrypted data, which could only be decrypted using the correct (old) password. Changing read-access to encrypted data doesn't make it useful.

This distinction comes down to what the password is being used for: is it being simply used to gate read/write access, or is it being used as the passphrase for an encryption/decryption key? On most IMAP servers, the password serves the former purpose, which is inherently less secure than the latter purpose. Nimur (talk) 19:38, 24 January 2012 (UTC)

I first thought the same thing as User:66.46.213.4, that although the site administrators don't know your current password, they certainly can either let you change it or change it themselves. But after I read your reply, I understood that a really secure site isn't just using a password to gain access to data, it's using a password to the data itself. JIP | Talk 21:26, 25 January 2012 (UTC)

Sophos and Spyware Quarantines

I am running Windows 7 with Firefox, and Sophos is my anti-virus program. Twice now in recent days, Sophos had quarantined spyware. The first was MAL/ExpJS-N. Sophos's "delete" and "move" options both failed, but when I rebooted for another reason later in the day, I noticed the quarantine area was then empty. Today, another quarantined gizmo shows up as quarantined. This one is named Troj/ExpJS-N. Both "delete" and "move" fail for it, too. I haven't yet rebooted to see what that does. These two spyware nasties seems to be more or less the same thing.

Question one: Is the second one the first one that didn't really go away, or do I have two separate, but similar, viruses?

Question two: Is it safe just to leave these viruses quarantined, or can they still do damage? Bielle (talk) 17:57, 23 January 2012 (UTC)

I do not know. Quarantined virusses are unable to do damage, and you can delete them from the quarantine if you want to. Von Restorff (talk) 19:51, 23 January 2012 (UTC)

That's one of the problems. I cannot delete it. The message comes up: Delete failed. Bielle (talk) 19:54, 23 January 2012 (UTC)

You cannot delete it from the quarantine??? That is weird. Reboot, and check if it is still there. Did you try running malwarebytes? Von Restorff (talk) 20:59, 23 January 2012 (UTC)

According to Sophos, the Troj/ExpJS-N has been around for about two years, and arrives via social websites etc. MAL/ExpJS-N is more recent, and seems to masquerade as anti-spyware, though they both seem to be obfuscated Javascript that directs your browser to dangerous websites. I'm puzzled by the failure of delete and move because Sophos seem to be aware of the malware and able to deal with it. Just in case the malware has somehow slipped through, follow Von Restorff's advice and download (free) Malwarebytes, update it, and run it once, just as a backup check. Dbfirs 09:10, 24 January 2012 (UTC)

I updated Malwarebytes and ran it. Everything came back clean (0). Troj/ExpJS-N was still showing as "quarantined" in Sophos when the Malwarebytes scan finished. Once again, I tried "delete" and when that came back "Delete failed" again, I rebooted. So far (2 hours and several visits to Fb, my email and WP later), "Quarantine" in Sophos remains empty. I'll be back if It returns. Thanks for your help. Bielle (talk) 17:17, 24 January 2012 (UTC)

If it reappears clean it again, then create a new restore point and then delete all but the latest restore points. Von Restorff (talk) 19:54, 24 January 2012 (UTC)

Free certificate authorities?

It may be possible that we have to install a web application we're delivering to our customer as an SSL application. For this we need a certificate signed by a trusted authority. Verisign seems to ask for about 500 to 1500 € for a certificate valid for about two to three years. It's possible that our customer doesn't want to pay that much. Are there any free trusted certificate authorities? JIP | Talk 20:10, 23 January 2012 (UTC)

You can self-sign and distribute your certificate directly. Nimur (talk) 20:22, 23 January 2012 (UTC)

In other words, you are free, and you are trusted by your customer, and you can make a certificate... so, you are a "free trusted certificate authority." Nimur (talk) 20:35, 23 January 2012 (UTC)

I'm afraid I didn't place my question clearly enough. The web application is going to be open to the public. It's a service our customer are providing to the public, we're just coding it. The communication is going to be between our customer and the public, not between us and our customer. The public isn't going to want to go through an extra step of accepting a previously unknown certificate, they will want it to just work. JIP | Talk 20:57, 23 January 2012 (UTC)

Then, you will need to purchase a certificate from one of the "trusted" authorities (or their authorized re-sellers). Certificates issued by these agencies are trusted by default in several major modern web-browsers. Here the a list of authorities that are trusted by default, in recent builds of Mozilla Firefox. You can buy directly from one of these agencies, or from one of their certificate resellers. A similar list of agencies exists for Internet Explorer, Safari, and so on. For example, Apple publishes its Program Requirements for root certificate authorities. Similarly, Microsoft publishes its Microsoft Root Certificate Program rules. Android devices are pre-programmed to trust root certificate agencies by the hardware vendor, specific to each hardware vendor's variant of the operating system; for example, here is Motorola's ANDROID - Root certificate management policy. If you want the certificate to "just work," you need to pre-purchase "trust" from an agency (or multiple agencies) to cover each platform you care about. Nimur (talk) 22:20, 23 January 2012 (UTC)

Yes, probably the most well known 'free certificate authority' is CAcert.org which consider themselves community based. However they haven't been included in any well known browsers AFAIK. As our article mentions, there was discussion of including them in Firefox at one stage, but this was abandoned after an audit raised concerns over some of their practices. See also [18]. Nil Einne (talk) 23:24, 23 January 2012 (UTC)

USD 500 for 2-3 years is high. Shop around, I think I paid USD 60 per year last I bought a cert (not telling where I bought it so as not to advertise, and so you can maybe find an even better price.) Captain Hindsight (talk) 16:03, 24 January 2012 (UTC)

January 24

One computer, several network connections

Can you connect a computer (running Linux or Windows) to several Wlans and wired networks at once? Since you can add different wireless adaptors (through USB, for example), a shortcoming from the part of the network cards should be an impediment. 88.8.69.246 (talk) 15:04, 24 January 2012 (UTC)

The simple answer is that yes, you can connect to multiple networks at once, assuming you have multiple NICs (e.g. one wired, one wireless, giving two connections). However, actually using them simultaneously can be difficult. The solution will depend on what you wish to use them for. Are you trying to connect to the internet through multiple networks (in the past I have been on a flaky WiFi network, and used a 3G dongle as backup), or are you trying to stream home media through a wired network whilst internetting through WiFi, for example? There are hardware and software solutions that can be used, some of which get into the realms of 'pretty damn technical'. - Cucumber Mike (talk) 15:41, 24 January 2012 (UTC)

I was trying to use two wireless networks at once with a laptop. It has its wlan embedded, and I have a wifi pen-driver adapter. One network is the work network (so, no torrent download) and the other is a free network of a coffee place (which is perfect for downloading private torrents). Just trying to connect to both wlan doesn't work, although each one works fine for itself not simultaneously. 88.8.69.246 (talk) 15:53, 24 January 2012 (UTC)

Some people here and here are discussing this. The consensus is that it is difficult if not impossible, and the only feasible way is to virtualize an OS and present one of the adapters virtually to the OS --rocketrye12 ^{talk/contribs} 16:30, 24 January 2012 (UTC)

It's neither impossible nor very difficult. Connecting two networks turns your linux computer into a network device called a "router" or "network bridge". You may be familiar with such devices. The difficulty is that somebody - you, or your network administrator - must decide which traffic should route to which network: hence, routing.

If you'd like an overview, I found "An Introduction to Networking" in the NetBSD manual/user-guide. It contains a good explanation of multiple addresses, and the implications therein. Almost every tool discussed in this guide has a commonly-available free software version, and is generally available on most distributed variants of Linux.

On Windows platforms, particularly on the desktop operating system versions, "Network Bridging" is available, which is similar to general purpose internet protocol routing. Nimur (talk) 17:56, 24 January 2012 (UTC)

(Specific instructions: 24.6. Setting up a network bridge device, and 24.5. Setting up an Internet gateway with IPNAT). Nimur (talk) 18:25, 24 January 2012 (UTC)

I used to do this with Microsoft Virtual PC and 2 NICs and 2 CAT5 cables, very easy stuff. Von Restorff (talk) 05:33, 25 January 2012 (UTC)

"Unblowing" eFuses using a focused ion beam

I've read that fuses like those found in embedded processors can be reconnected using a focused ion beam. Is this expensive? Does it work? --Melab±1 ☎ 21:33, 24 January 2012 (UTC)

I'm guessing the cost depends greatly on whether you already have access to a focused ion beam. Since you probably wouldn't need to ask if you did have access, then I expect it would be expensive to purchase commercial access (if anyone does that) or worse buy a machine for that purpose. It may not be so expensive if you can convince someone to give you access at a research institution, which you could potentially do if you have some research that requires it, particularly if you have the backing of an institution or are a known researcher. But if all you're trying to do is to flash a locked Motorola phone then I suspect you're likely to be ignored if you ask for access. Nil Einne (talk) 23:26, 24 January 2012 (UTC)

Not too long ago, somebody asked if they could forge metal by melting down fountain pens. Your question is very similar to that question. Yes, in principle - this can be done. In fact, somebody, somewhere, owns a machine that can accomplish this task. Can you use a focused ion beam to perform surgical semiconductor modification? Yes - and you can also melt down fountain pens to extract the trace precious metals from them - but come on. Let's be realistic. This isn't going to happen. You don't have the expertise, the money, or the equipment. The knowledge of how to perform such a procedure is so specialized, that even Wikipedia, which has an article on everything, doesn't even have ion beam epitaxy... (probably we should link that to molecular beam epitaxy). This process is so specialized, so prohibitively expensive, ... that it's not going to happen. Be patient, excel academically, and do some research in a materials science or electronics lab, and eventually you'll be able to work on some cool stuff. Unfortunately, it's a fact that certain activities, like semiconductor lithography and steel blast-furnace operation, just aren't hobby-projects for the technical enthusiast. They never will be. Nimur (talk) 23:37, 24 January 2012 (UTC)

And even if the actual modification was cheap and easy, the getting into a position to do it on a real device would itself be an expensive undertaking. First one would have to deencapsulate the semiconductor (in a very clean environment) Then one would have to build up a detailed understanding of the circuitry (either by optical or electron-microscope examination), which is particularly difficult if the chip is heavily layered. Assuming the desired microcircuitry is accessible (that is, assuming it's not buried under other stuff) one would then do the beam thing. One would then need to reinstate the insulation, the thermal bonding, and the ceramic encapsulation. Doing this kind of thing only makes sense when one is trying to penetrate a sensitive package, presumably for the purposes of crime or intelligence gathering. And the kind of chips that organised criminals and intelligence agencies will want to crack will have layered protection against such penetration (where tampering with the packaging destroys the chip and wipes its payload). 87.113.28.157 (talk) 01:44, 25 January 2012 (UTC)

January 25

Can a JavaScript alert appear when browser is minimised?

I am developing a JavaScript countdown timer. Can I make the timeout alert pop up even when the user is using another application, such as OpenOffice? In my office, the computers have no Internet access and no access to removable media. — Preceding unsigned comment added by 203.116.187.1 (talk) 02:26, 25 January 2012 (UTC)

In Internet Exploder? Yes. Chrome? Yes. In Firefox? No, because of security. (tested in latest version of browsers with this example). Javascript isn't the best language for this sort of thing. Von Restorff (talk) 03:00, 25 January 2012 (UTC)

What about for older versions of IE, like IE6? — Preceding unsigned comment added by 203.116.187.1 (talk) 03:47, 25 January 2012 (UTC)

In Internet Exploder 6 it works too. Von Restorff (talk) 03:54, 25 January 2012 (UTC)

Or at least make the browser button in the taskbar flash? — Preceding unsigned comment added by 203.116.187.1 (talk) 03:49, 25 January 2012 (UTC)

In FF that is not possible, in the other browsers it is not necessary. Von Restorff (talk) 03:57, 25 January 2012 (UTC)

Could I do this with OpenOffice.org Basic? — Preceding unsigned comment added by 203.116.187.1 (talk) 03:49, 25 January 2012 (UTC)

Probably. What do you want the program to do, and why? Von Restorff (talk) 03:57, 25 January 2012 (UTC)

I'm guessing the OP wants to make some sort of alert show up, but can't use a program designed for that purpose since the computers have no simple way to receive files so it needs to be implemented in situ with whatever is already on the computer. I wonder if some sort of simple default scripting program present on the computers may be a better idea. E.g. VBscript for Windows. It obviously won't be particularly cross platform. Alternatively, just add a scheduled task to say open an PNG saying 'GO HOME NOW' or whatever may work. (In *nix I presume you can implement something in Cron.) Nil Einne (talk) 04:50, 25 January 2012 (UTC)

After 48 editconflicts: In OpenOffice Basic the following code makes the button in the taskbar flash:

wait 12000

msgbox "pizza"

Von Restorff (talk) 04:55, 25 January 2012 (UTC)

---

A VBS version: make new textdocument. Rename it to test.vbs. Use the following code:

WScript.sleep 12000

msgbox "pizza"

Von Restorff (talk) 05:15, 25 January 2012 (UTC)

Keyboarding Pro 4, Pro 5 , Pro 6 and Keyboading Course 1-25 w/Keyboarding 6

I am a student using Pro 4 when I get to the textbook I do not have a text book. Is Pro 5 or Pro 6 compatabile to use in the place of Pro 4 book? Pro 5, Pro 6 and Course 1-25 the same? My computer 2007. If you need ISBN Number 11142465, 111426465, 0840053320. If there is a different way for a different program including a cd and textbook. Your advie would be appreciated. Thank you very Much — Preceding unsigned comment added by SinderKod (talk • contribs) 03:24, 25 January 2012 (UTC)

Just to make sure I understand, you are trying to learn to touch type on a QWERTY keyboard, right ? Is this a US English keyboard (with a dollar sign instead of pounds sterling) ? StuRat (talk) 18:45, 25 January 2012 (UTC)

SQL query

Hi. How do I perform a query in SQL which selects all items from table A which do not appear in table B? Thanks. --163.202.48.125 (talk) 10:03, 25 January 2012 (UTC)

Something like SELECT * FROM A WHERE id NOT IN (SELECT id FROM B) would do it. AndrewWTaylor (talk) 10:19, 25 January 2012 (UTC)

Thanks - I tried that but it takes too long because table B is a list of transactions and table A is also quite big. Is there any way to do the inside query first (i.e. the (SELECT id FROM B))? That way it only gets done once. --163.202.48.126 (talk) 10:48, 25 January 2012 (UTC)

You could extract the relevant IDs from B into a temporary table, perhaps using SELECT DISTINCT to keep it to a reasonable size. If you need to do the query regularly you could put it in a stored procedure. AndrewWTaylor (talk) 13:35, 25 January 2012 (UTC)

Another way is to use "where not exists". There is a difference in the handling of nulls, see e.g. [19] or search the web. Captain Hindsight (talk) 10:44, 25 January 2012 (UTC)

Many databases allow you to do this "set difference" operation directly: Set_operations_(SQL)#EXCEPT_operator. --Sean 16:59, 25 January 2012 (UTC)

You might want to try to JOIN both tables and see where table B contains NULL values. Any SQL server will be optimized to do joins. "Where not id in ..." constructions are inherently slow if the server takes it literally, but for example MS SQL seems to be smart enough to understand what you mean and secretly turns your query into a JOIN-operation. Do make sure you have the right indexes on both tables! Joepnl (talk) 23:44, 25 January 2012 (UTC)

Image Processing using Fourier Transforms in MATLAB

Hallo all,

I am stuck in a problem where I have images of a car at various distances and from these I have to estimate the visibility. My approach was to take the Fourier transforms of all images and then filter out the low frequencies leaving only the high frequencies, which correspond to sudden changes in pixel values. Then I made a scatter plot of the mean values of the amplitudes of the Fourier coefficients against distance of the cars to see the general trend.

However the scatter plot is inconclusive. While the amplitudes do attenuate gradually, there are too many outliers. Does anyone know if there is a better metric than mean which could be used to analyze the trend? Thanks in advance! :-) 141.113.85.93 (talk) 10:15, 25 January 2012 (UTC)

Can you explain a bit more ? Are you are trying to detect fog, smoke, smog or some other factor which limits visibility ? More distant objects should appear less colorful, and the edges should also be fuzzier, which implies that either looking for less color variation or using an edge detection method might work. And one obvious potential problem is the lens on the camera you are using clouding up. Is it heated to prevent this ? StuRat (talk) 18:34, 25 January 2012 (UTC)

Patent for content downloads

Resolved

Hi all, someone told me that some person has managed to score a patent for content downloads on iTunes, meaning those in-app purchases you can make, like pay an extra $1 and remove adds etc. Is this true, because it sounds like something that would have been big news? And what is the correct term for content downloads/ in app purchases? I get meaningless hits on google, so I must have the wrong term. Thanks, IBE (talk) 10:55, 25 January 2012 (UTC)

'Content downloads' is confusing since downloading music or apps from iTunes is obviously a content download. And content download is also what some apps do after install and first run (at least on Android). But neither of these seem to be what you're referring to. If you're referring to 'in app purchases' meaning buying stuff inside an app then a simple search for 'in app purchases patent' will find the name Lodsys for you. And plenty of sources discussion the dispute e.g. [20] [21]. It also seems from that search that Apple themselves filed for a patent [22] in 2010. (Considering I'm pretty sure Facebook games have were doing it before 2010 and free to play MMOs which are particularly common in East Asia before that (i.e. plenty of prior art), I'm not sure how successful they will be. But I guess it will depend on the specifics of their patent and how obvious the jump from what the free to play people were doing, so only time will tell.) Nil Einne (talk) 12:55, 25 January 2012 (UTC)

http://www.groklaw.net is arguably the best source of info on the Lodsys case, should you want to hunt for more details. --Tagishsimon (talk) 13:12, 25 January 2012 (UTC)

That's "http://", not "http:\\". I've taken the liberty of editing your comment, as confusion between the forward slash and the backslash is a personal pet peeve of mine. JIP | Talk 21:56, 25 January 2012 (UTC)

Thanks - scary business. I've put it as resolved, but people are free to add more, and I'll be back to check - quite an interesting discovery. IBE (talk) 14:11, 25 January 2012 (UTC)

Is there a way to call a toll free number without them seeing your number that doesn't cost a fortune?

As caller ID blocking has no effect on the ANI (automatic number identification) system toll free number uses, I can't find a way to do it without some calling card or VoiP system that costs something like 20 cents a minute. And the free VoiP stuff that give samples are only 3 minutes which is too short. About 20 years ago I read some text that said there was some way to turn the whole ANI system off for the call but then you'd pay for the long distance call, but that was 20 years ago and I don't remember. Are you ready for IPv6? (talk) 20:49, 25 January 2012 (UTC)

I believe you can call 800-numbers for free on Skype. Other than that - Use a payphone. ^Avic_ennasis @ 23:55, 1 Shevat 5772 / 23:55, 25 January 2012 (UTC)

Or, route your call through a different long-distance carrier, using 10-10 codes, or call the operator and have them place the call for you - both of those will also tend to obscure ANI info. (Handy tidbit for testing - MCI, via 1-800-444-4444, will have an automated system playback the ANI number it received.) ^Avic_ennasis @ 07:25, 2 Shevat 5772 / 07:25, 26 January 2012 (UTC)

Brute-force attacks against Gmail passwords

Hi,

According to [23]: "For reasons too complex to explain here, even some systems, like Gmail’s, that don’t allow intruders to make millions of random guesses at a password can still be vulnerable to brute-force attacks." How does this work?

Thanks. Apokrif (talk) 21:42, 25 January 2012 (UTC)

For starters they could brute force some other system that uses the same password, or has a copy of the password in plain text. ¦ Reisio (talk) 21:53, 25 January 2012 (UTC)

Or by rate-limiting the brute-force password-guess attempts to a rate below the detection threshold; or hopping IPs by using a bot-net. Basically, counter-countermeasures - playing the part of the cat in the cat and mouse game. Nimur (talk) 21:55, 25 January 2012 (UTC)

Or use a combination of brute force, but somehow restricted by a dictionary. Just try the passwords like 'mypassword' in thousand of gmail account. I'm sure you'll find somehting. — Preceding unsigned comment added by 88.8.69.246 (talk) 23:10, 25 January 2012 (UTC)

This is probably referring to brute forcing many different accounts in parallel from many different machines, by people who just want compromised accounts and don't care whose. Gmail can rate limit logins by source IP or by account, but when both the source IP and account are different each time it's just business as usual. -- BenRG (talk) 01:08, 26 January 2012 (UTC)

Combining a botnet with a captcha solver and a good dictionary makes this stuff easy. But I prefer iStealer, much easier. Von Restorff (talk) 01:35, 26 January 2012 (UTC)

That program appears to be a user-interface for building semi-customized trojan software. Those types of attacks constitute a totally different class, and are not brute-force attacks. Trojan programs are also much easier to defend against. I simply choose not to run untrusted software, and so I am immune by default to the entire category of attacks that "iStealer" makes so easy. Protecting my computers from distributed brute-force attacks is more difficult. Nimur (talk) 07:13, 26 January 2012 (UTC)

Ever heard of using a binder to make it FUD? If the goal is to get Gmail passwords using iStealer is much easier than using a combination of a botnet with a captcha solver and a good dictionary. If you have a brain the size of a planet you can steal a botnet, if you have some money you can pay for a captcha solving service, and good dictionaries are easy enough to download, but still this is much harder than using iStealer. Protecting from bruteforce attacks is pretty easy actually; I am using Extreme GPU Bruteforcer and it would take a very very long time to crack my own TrueCrypt password. And if you do there is a second layer of encyption. I live too far away, but if we lived in the same house it would cost just 5 dollars to get your passwords. Von Restorff (talk) 08:05, 26 January 2012 (UTC)

January 26

Where can I learn to build my own mobile apps?

As you can see on the comments here, 11-year-old Caleb claims that he makes Android & iPhone apps. He obviously didn't learn to in college.

Where would I learn to build them myself, and would it cost anything to learn to build apps? Thanks. --70.179.174.101 (talk) 04:21, 26 January 2012 (UTC)

iOS apps are written in Objective-C. There's probably a book about it somewhere out there. →Στc. 04:33, 26 January 2012 (UTC)

Do you already know how to design and develop software? If so, head straight to developer.apple.com/ios or developer.android.com to learn the specific toolchains on these popular platforms. I also liked developing mobile software for Java ME telephones and devices, though it's a technology that's somewhat fallen out of favor in recent years. If you are not already a software developer, you may find the mobile development enviroment somewhat challenging; there are a lot of complex systems to learn and a lot of terminology you are unfamiliar with. Furthermore, these platforms tend to require expensive hardware and software tools, if you intend to develop a well-designed and well-tested application. (Though, to be fair, it is possible to learn and develop with a very small budget, especially if you are an exceptional learner). Start by reading about software development in general, and seriously invest some time learning how to program computers. After you've developed a basic proficiency, select one or more platforms,and focus on learning the software toolchains and workflows for each system. Nimur (talk) 06:56, 26 January 2012 (UTC)

For a quick fix, go to your favorite Internet search engine and type in iphone programming tutorial. You'll find articles, videos, and books. Maybe start with a couple of video tutorials. Captain Hindsight (talk) 10:38, 27 January 2012 (UTC)

why is my sparkle nvidia geforce 210 512mb graphics card not working?

hello......... i brought a Sparkle nvidia geforce 210 512mb ddr3 graphics card. but whenever i plug it in my motherboard it is not detecting only...... i changed that graphic card and replaced it 3-4 times from the shop but the problem is same... ealier i was having windows xp and in that my graphic card was working but at that time my computer used to freeze and appear blue screen...... so i formatted and istalled windows 7... but now when i installed windows 7, my graphics card has become undetectable...

I did following things but the problem is same:-

1. i downloaded latest driver from nvidia's site
2. i replaced the graphics card 2-3 times as it is under the warranty period
3. i am also having INITIAL DISPLAY in the BIOS settings to PCI Express Card
4. i am also having enough power supply for the graphics card

BUT INSPITE OF DOING ALL THESE THINGS THE PROBLEM REMAINS THE SAME...

My Computer Specs are as under:-

Motherboard: Mercury Pi945GZD
Processor: Dual core
CPU: 3 GHZ
RAM: 3 GB
HDD: 160 GB
OS: Windows 7 Ultimate 32 bit
Power Supply: 300 watts

I did each and every thing possible to make my graphics card work.... but nothing changed

plzzzz plzzzzzz plzzzzz help me — Preceding unsigned comment added by 49.213.50.64 (talk) 06:52, 26 January 2012 (UTC)

It sounds as though you've already performed the standard set of hardware and software diagnostics. I would double-check that your power supply is in fact sufficient to power your entire system - as this is the most probable source of problems. Because you have already replaced the graphics card 2-3 times, it's unlikely that the cards were all faulty - but what about the motherboard? It's plausible that your system board has a defective PCIe interface. Have you tried using the card in another system/motherboard? Nimur (talk) 07:01, 26 January 2012 (UTC)

(I have also formatted your wikitext for better readability). Nimur (talk) 07:04, 26 January 2012 (UTC)

You have to be more precise. What do you mean by "undetectable"? Are you able to get past BIOS when you plug the monitor into that card? Can you boot into Windows? If you can get to Windows, what happens then? --Itinerant1 (talk) 08:39, 26 January 2012 (UTC)

Why is it that some people, who otherwise spell English well, like the OP here, insist on spelling the word "please" as "pls", "plz", or $DEITY forbid, "plzzzz"? Even our company's Director of Human Resources spells English otherwise almost perfectly correctly, but consistently spells "please" as "pls". JIP | Talk 20:19, 26 January 2012 (UTC)

I've started to see this as a sign of disrespect. When writing to someone who needs to be respected, most people can be relied upon to spell out words completely. This is especially true of 'please', which is somewhat of a placeholder in English - just there to fill the space in phrases like Please do this (meaning Do this). If someone abbreviates it to pls, they are showing that they don't really want to say please, they just require it to fill up the sentence. I imagine that the fact it's your HR Director that's doing this is not a coincidence. - Cucumber Mike (talk) 10:31, 27 January 2012 (UTC)

Information Technology Foundations

What are the basic objects that computers process? How do computers handle music and video? — Preceding unsigned comment added by Crexia (talk • contribs) 12:21, 26 January 2012 (UTC)

The term "computer" in modern usage almost always means a digital electronic device. Since it is a digital device, everything that it handles is captured as a set of discrete numbers or integers - and all modern computers use a binary representation to store these numbers. For an outline of how music and video can be turned into numbers, see our articles on digital music and digital video. Gandalf61 (talk) 15:28, 26 January 2012 (UTC)

By random chance, I came across an excellent book last night, by a famous computer researcher, Brian Kernighan. His new book, published in 2011, is called D is for Digital - What a well-informed person ought to know about computers and communications. I haven't yet had a chance to read it, but it seems to be geared towards informing the general public about how computers work. And, if it's like the author's previous book ("C", with similar book cover stylings), it's probably simple, informative, accurate, and thorough. According to reviews, it walks the average computer user through the technologies that make their day-to-day activities possible. Nimur (talk) 16:22, 26 January 2012 (UTC)

Making a New Word Doc from An Existing doc

How can I get, say, pages 59 to 72 as a separate document in itself? KägeTorä - (影虎) (TALK) 13:20, 26 January 2012 (UTC)

Maybe I am missing something here, but can't you just copy the document file or "Save As ..." to a different file name, then delete the pages you don't want ? If you want to preserve the original page numbering then the "Format Page Numbers" dialogue has a "Start at" option. Gandalf61 (talk) 13:47, 26 January 2012 (UTC)

Cheers, all done. This was for entering in memoQ. Thanks a lot. Sometimes simple is just too simple. KägeTorä - (影虎) (TALK) 14:18, 26 January 2012 (UTC)

drop-in code for a survey on my web page

Can you tell me where I can use an external complete solution like a linked image, but the site hosts a quick little survey for me. I use a pretty bad host, I think it barely has PHP support, and I certainly don't have root, so what would really help is just a line of HTML I can just drop in. --188.6.79.116 (talk) 15:13, 26 January 2012 (UTC)

The easiest option is to use Google Docs to create a form, and then use a small IFRAME to display it on the page. I've used this for surveys before; it's pretty easy. Go to Google Docs, go to Create, go to Form. After you've set up the form, go to "Embed" and it'll give you the one line of HTML to make it display. It saves the submitted data as a spreadsheet and doesn't let anybody other than you access it. --Mr.98 (talk) 17:31, 26 January 2012 (UTC)

So what happenswhen you divide by zero?

In a calculator, nowdays if you try to divide by zero it will cancel the operation and display that message.. What happens when you got a calculator that is not modified to stop the operation when the divisor is at 0? what the calculator is going to do? what it is going to display? --190.60.93.218 (talk) 19:53, 26 January 2012 (UTC)

Calculators aren't 'modified' to detect a division by zero, they are designed that way. If they were designed to do something else, they'd do that instead - but whatever it was, it wouldn't give a meaningful result. AndyTheGrump (talk) 20:04, 26 January 2012 (UTC)

...and we even have an article on division by zero, which goes into further details. AndyTheGrump (talk) 20:07, 26 January 2012 (UTC)

What type of calculator? This matters a lot. Even though calculators are very small, they have sophisticated microcomputers inside of them, and may be running arbitrarily-complex software. For example, a TI-89 has an operating system and a symbolic algebra system to interpret your input. It will very probably return the result "∞", depending on your mode and your input.

In IEEE-754, which is implemented in some newer and larger calculators (and most desktop computers), the result of a double-precision number divided by zero is positive or negative infinity, or NaN, depending on your input; and this is not considered an "error." The result of an integer division by zero is a processor exception or an ALU error flag on many computer types.

The ultimate point is, this behavior should be well-documented in the hardware or software specification for your calculator. If you're running a calculator that doesn't come with a manual (as many small desktop and pocket calculators), you may be able to research its inner-workings on the web by searching for its brand and model. Nimur (talk) 20:42, 26 January 2012 (UTC)

It seems that this is what you are looking for - Cucumber Mike (talk) 10:24, 27 January 2012 (UTC)

We have an article on division algorithms at Division (digital). I would imagine that all computers and calculators for a long time have been designed to check for a zero denominator before trying to carry out division, but what would happen if they didn't would depend on the algorithm being used. For example, you can see that in Newton-Raphson division, a denominator of zero would lead to the initial estimate being doubled at each step until Arithmetic overflow occurs. 130.88.73.65 (talk) 11:35, 27 January 2012 (UTC)

radical new-age solution

a good solution would be to just reduce everything except any divisions by zero, and display that as-is. In other words, the ansewr to (34+56)/0 would be displayed as 90/0 (in red to draw attention to the fact that it's NaN in the traditional, left-brained white male hegemony sense of the word, or with a note to that effect) and the user can decide for themselves existentially what that means for them. Probably a mistake typing the formula in. — Preceding unsigned comment added by 188.6.79.116 (talk) 17:12, 27 January 2012 (UTC)

What's (30/0)+20? --Stephan Schulz (talk) 17:21, 27 January 2012 (UTC)

This isn't really very "radical," either. Most computer algebra systems can perform such operations. For example, the simplify() command in Maple will perform such symbolic algebraic manipulations. It will try to reduce the expression to the simplest representation that is mathematically consistent (using a sophisticated algorithm). My TI-89's battery is currently discharged, but as soon as I get home and swap in some new ones, I'll let you know how TI-89 processes or evaluates such symbolic statements as "(34+56)/0" or "(30/0)+20". A quick glance at the TI-89/92 Guidebook has an entire chapter on Automatic Simplification for symbolic expressions. As I mentioned before, there are circumstances when a divide-by-zero will fail - for example, in the numeric algebraic equation-solver, which in some cases will not produce symbolic results - the result is Calculator Error Code 160. "For example, zeros(2x+3=0,x) is invalid because the first argument is an equation."[24]. Personally, I don't see what NaN has to do with left-brained white male hegemony. Every person I ever knew who worked on symbolic algebra algorithms was a female. Nimur (talk) 18:49, 27 January 2012 (UTC)

90/0 is +∞ in IEEE floating point, not NaN. Note that x/0 (with x a nonzero integer) reduces to 1/0 if you follow the usual rules for reducing fractions to lowest terms, so distinguishing 1/0 from 2/0 makes no more sense than distinguishing 1/2 from 2/4. 1/0 would be a reasonable representation of +∞ or signless infinity in an arbitrary precision rational number package. -- BenRG (talk) 18:50, 27 January 2012 (UTC)

Just for the record, the TI-89 and most of the other TI calculators do not use IEEE floating point. They use an 80 bit floating-point scheme. This is sufficient justification for me to call a Texas Instrument a "weird" computer. (Argh, TI has removed their `89 Software Developer documentation since the last time we talked about it, in 2010 If anyone finds the `89 hardware/software guide, please feel free to post the new link). Nimur (talk) 18:54, 27 January 2012 (UTC)

If you implemented a division algorithm in a straightforward fashion (not necessarily what the calulator actually does), and left out a check for that case, division by zero would probably run forever (probably it would perpetually shift the zero up, trying to find a non-zero digit in the right place). There is some sense in which this is a "natural" failure mode for certain calculations of undefined values: a boolean function like f(x)= not(f(x)) is "wrong" in the sense that any value it returned would need to satisfy y = not(y), which is impossible. But f doesn't return any value. In programming languages like ACL2 that treat programs as proofs, you're not allowed to define a function without also proving that it does terminate. In such a case, division has to be defined as a partial function -- you'd need to declare that division by zero is not valid in advance. Paul (Stansifer) 03:10, 28 January 2012 (UTC)

January 27

Hard drive prices -- am I missing something?

Hello! I've been looking around to buy an internal hard drive, and found most 500GB models running about $70-$80 (USD) or more. I found an old electronics catalog from 2010, and was surprised to see 1+TB drives from the same manufacturer running about $70-$80 as well, with comparable RPM values, data transfer rates, etc. In fact, I looked back at my receipts and saw I scooped up a 1.5TB Seagate Green for $50 last summer. Now I can't find a 1TB drive for much cheaper than $100. Am I missing something? What's changed in the last few months to drive up hard-drive prices? Talking about the non-SSD variety. Thanks for any insight!--el Aprel (^facta-_facienda) 08:37, 27 January 2012 (UTC)

• Western Digital had a factory flooded in the 2011 Thailand floods. Graeme Bartlett (talk) 08:43, 27 January 2012 (UTC)

It wasn't just Western Digital affected. Companies producing parts for HDDs including Nidec who make motors were also affected [25]. (Seagate also has factories in Thailand (and is building more) but they weren't directly affected [26].) Seagate and WD claimed supply won't return to normal for 9 months to 2 years [27] [28] [29]. A reduced supply with consistent demand naturally results in higher prices. But it seems to have resulted in a panic with large vendors and computer etc manufacturers shoring up contracts to guarantee supply and HDD manufacturers drasticly reducing supply to customers without contracts to ensure they can meet contracts [30] [31] [32] [33], meaning extreme shortages (and very high prices) for end user purchasers. IMO there's also a bit of an ongoing bubble and price gouging going on. This was widely discussed in October-December [34] although there's still discussion of what's going on in production, e.g. Western Digital has resumed slider production [35]. Nil Einne (talk) 12:53, 27 January 2012 (UTC)

Very informative answer. Thank you!--el Aprel (^facta-_facienda) 00:54, 28 January 2012 (UTC)

Video from iTunes on Windows computer

I have an iPhone (3Gs, if that's relevant to my question) and a Windows 7 desktop. I know I can buy audio content through iTunes on my phone, back it up on my computer, and play it on my computer using the Windows iTunes program, but is it possible to do the same with video, such as if I bought a movie on my phone? Does the iTunes program for Windows have the ability to play movies bought on iTunes on my desktop? If I'm lucky enough that the answer is yes, does anyone know if a rented movie would work for the rental period on my desktop? My desktop iTunes is of course configured to my account. 20.137.18.53 (talk) 12:44, 27 January 2012 (UTC)

If it's something you have downloaded to the physical device, iTunes or some other software should be able to copy it to a desktop computer. I don't know how your renting system works, but it might at least be possible to redirect the video and audio to a larger screen, like that of a desktop. ¦ Reisio (talk) 21:51, 27 January 2012 (UTC)

http://www.htc.com/in/smartphones/htc-sensation-xl/ link does not work.

http://www.htc.com/in/smartphones/htc-sensation-xl/ link does not work for me in Chrome, Firefox or IE9. What could be the reason? — Preceding unsigned comment added by 115.249.68.50 (talk) 12:58, 27 January 2012 (UTC)

I doubt anyone here will know precisely why a certain page on HTC's webserver doesn't work. The NZ page works fine [36] as does the Australia page [37] and I would expect the feature set of the phone to be the same so if that's all you want to see you could check out those pages. Nil Einne (talk) 13:22, 27 January 2012 (UTC)

I should have asked the question clearly. The link in itself works to show the page. But the buttons 'Overview', 'Specs' etc do not work. They did not work for me in the NZ or AUS sites too. Was wondering why. — Preceding unsigned comment added by 115.249.68.50 (talk) 13:36, 27 January 2012 (UTC)

Those two links use target specifiers to define a position on the page (in this instance the same page you're already on) to jump to. These are the #overview and #links components you can see on the destinations if you hover the cursor over buttons. It looks like the relevant anchors have been left off the page. Rojomoke (talk) 13:56, 27 January 2012 (UTC)

Well here in NZ the Indian page doesn't work at all, I get an 'Internal Server Error - Read'. I have no problems with the NZ or Australian pages including specs etc. Nil Einne (talk) 15:21, 27 January 2012 (UTC)

Oh and now the Indian page is working fine Nil Einne (talk) 17:05, 27 January 2012 (UTC)

"Are you sure you want to leave the page?"

I get this message often when I attempt to ex-out of a tab. I use Firefox on an iMac. When I click out of tab or window I just want it to work without this extra hoop. Is there a way to stop this? I have no idea if this is my computer, my browser, the website issuing the message, or some setting betwixt the three.--108.46.103.88 (talk) 14:25, 27 January 2012 (UTC)

it's the web page, it gets to tell your browser to do that. It's usually useful, for example if you spend an hour filling out an application and resume/CV all as form fields, it's a pain if you close it accidentally. that's why web pages get to ask your browser to do that. It's something in between a "save" and no protection at all. I don't know if there's a specific way to disable it (which would mean setting your browser to ignore requests like this from web sites. you might lose what you enter though, like closing a gmail tab before it autosaves!). 188.6.79.116 (talk) 17:05, 27 January 2012 (UTC)

Usually implemented in JavaScript, which one can disable, but for some things that are entirely JavaScript driven it won't help you. You might be able to find an extension that can block just the "extra hoop", though. ¦ Reisio (talk) 21:55, 27 January 2012 (UTC)

Thank you. I hope someone can provide that javascript solution but this issue is only a minor annoyance. I have never, to my memory, accidentally closed a tab or window and lost content. I have, however, worked for a long time on something and had my computer blue-screen-of-death me (when I was on a PC), or have had the material not save on the website's end for whatever reason. In response, I have long been vigilant about using a dump folder (I don't know if that's a real term but what I always call it). Basically, I keep a textEdit document open at all times, actually called dump folder, and any time I'm working on something I ctrl+a and then ctrl+v into it and ctrl+s (I know on a mac it's not ctrl, but that's still what I call it). I do this almost without thinking and very fast and after my save or whatever has worked, I dump the stuff from the folder.--108.46.103.88 (talk) 00:45, 28 January 2012 (UTC)

The Firefox extension Lazarus automatically does that for you. Paul (Stansifer) 12:49, 28 January 2012 (UTC)

Restart problem ........ Motherboard or software?

I had a problem with my desktop pc it restarts automaticaly within 2 hours. Recently there was a power fluctuation in my area and after that my smps got burnt I got it repaired by a nearby repair shop. but after that my cd player is not working and my PC restarts within 2hours. I showed it to a repair shop and they told me that it is a problem of motherboard and so they repaired it but the problem is as it was earlier. after that he reinstalled windows 7 but again the problem is there.

can anyone please suggest me that it is a problem of hardware or software and if it is problem of motherboard then is it repairable or not? — Preceding unsigned comment added by 220.225.96.217 (talk) 17:16, 27 January 2012 (UTC)

One possibility is that it's overheating. Does it have a thermometer you can access ? If not, you could try removing the case, and, if that doesn't work, try aiming a fan at it. If this fixes it, then temperature is the source of the problem. If you want a more elegant solution, clean everything inside with a mini-vacuum, upgrade your CPU fan and/or case fan and/or any heat sinks inside (those metal things with cooling fins). StuRat (talk) 17:43, 27 January 2012 (UTC)

January 28

Ordering a single Tegra 3 SoC

I am interested in buying a single, unsoldered Tegra 3 SoC. I know that Nvidia only sells to people order 100,000+ units, but could there possobly be some other company I could get one through, like a dev kit manufacturer? --Melab±1 ☎ 00:02, 28 January 2012 (UTC)

set up a shitty review web site on a free web host (domain will cost you $10), write a couple of positive articles about things along the same lines but from competitors, fill the rest with links, etc, and then write a letter to them saying you would like an unsoldered Tegra 3 SoC to review, in your email have a disclaimer that review items become your property along with a lot of other legalese. This exercise should take you 2-3 hours in total. --80.99.254.208 (talk) 11:38, 28 January 2012 (UTC)

Importance of checksums

Whenever I burn files to a CD/DVD, I calculate md5 checksums from the optical media and HDD for comparison, though I've rarely found inconsistencies (I also burn at lower speeds than I used to). Since I'm at times a little paranoid about data corruption, I calculate checksums for a lot of other file transfers, like over wired Ethernet, wirelessly over LAN, internal to external HDD through USB, and even between two internal HDDs over SATA. I've yet to find checksum inconsistencies with these transfers. Is doing checksum comparisons for files transfers like these (i.e. not involving optical media or unsecure Internet) really worth it? Or is the possibility of data corruption through these types of transfers limited to such outstanding scenarios (hard-drive failure mid-transfer, accidentally severing part of the Ethernet cable, etc.) that data corruption would be obvious (noticing the transfer was incomplete)? Thank you!--el Aprel (^facta-_facienda) 01:13, 28 January 2012 (UTC)

md5 is a cryptographic checksum, intended for resistance against deliberate tampering by malicious adversaries. It's total overkill when you're considering reasonable accidental data corruptions (but using md5 rather than a crc is mostly harmless). TCP packets are CRC checksummed already, and a failure will cause a retransmission. Similarly hard drives use CRC (and reed solomon) and so a silent failure (a copy that says it succeeded but actually was defective) is also unlikely. But there's no harm in continuing with md5 sums if you like. If you were really interested in cryptographically secure verification, you'd be wise to move from md5 (which is, at least in theory, no longer secure) to sha-512. 87.113.130.148 (talk) 01:25, 28 January 2012 (UTC)

To clarify/correct myself a bit: an ethernet frame has a frame check sequence which is a CRC32; if the packet is transferred over the public phone network it probably goes as ATM or SS7 packets, which are checksummed. Moreover IP packets have a header checksum (which doesn't check the data) and TCP packets have a cyclic (if rather rudimentary) checksum. In addition some file formats like PNG and ZIP add another layer of checksums. All of this makes it unlikely that the kind of errors that electrical problems cause will go unnoticed. 87.113.130.148 (talk) 01:44, 28 January 2012 (UTC)

I agree that our packetization protocols and data encodings make analog signal integrity problems very unlikely. Single-bit-flip due to electrical noise is fairly easy to detect and correct.

In the not-too-distant past, servers and routers often tried to outsmart your TCP packets: they'd do fun tricks like auto-detecting that your data was English text, so it could work "just fine" using only 7-bit ASCII. This would save the eighth bit could be reserved for internal use, or could be compressed, or whatever. Chaos ensued. TCP, as a protocol, couldn't correct for this sort of router or server optimization, because the system was "smart" enough to "fix" the packets for you. Another problem was servers who incorrectly detected your machine-type or operating system, and then delivered you binary data in the wrong endianness (instead of using network byte order). In theory, these sorts of techniques could be performed properly without corrupting your data, and they do have potential to improve network throughput, but they incur risks and software bugs can catastrophically damage the data stream, so some of these techniques have fallen out of favor. In their place, better and more robust server/router optimizations have taken root. I haven't seen this sort of packet-disrupting (mis)behavior in my network data transfers in several years. The internet has become much more homogeneous since the mid 1990s though - almost every server is a 32- or 64-bit Intel system; almost every router is made by Cisco (or a bit-accurate competitor). I wonder if we will see the resurgence of weird machine-specific optimizations gone haywire as we re-introduce heterogeneous computer types in the mobile space; your mobile telephony tower runs a MIPS processor that transmits internet data from a 64-bit Intel server to a mobile ARM processor ...

In short, you can trust the data integrity more if you checksum it. Nimur (talk) 01:47, 28 January 2012 (UTC)

I should also say that for secure Wifi (WPA or WPA2) ethernet, the packets themselves are encrypted (with TKIP or the AES-based CCMP system). So any foreseeable corruption there will break the cipherstream and the whole packet will fail to decrypt. 87.113.130.148 (talk) 01:55, 28 January 2012 (UTC)

These are all really good answers, particularly Nimur's point, which is something I hadn't heard about before but makes a lot of sense. I'd say about 87's point, the encryption will account for any over the air transmission skews, but I think (could be wrong) that 802.11 itself has additional checksums, as does over the wire ethernet. Introduced errors in a normal line are pretty difficult to slip through. As everyone's said, there's a ton of checksums working in parallel, however, for 100% peace of mind, md5 (or something more secure if you're worried about wholesale tampering... and that's a pretty big if) is an easy way to be 99.99999999999999% sure. Shadowjams (talk) 06:19, 28 January 2012 (UTC)

Yes, CCMP has a CBC-(AES)MAC, which is cryptographically robust; any change will cause that to fail and the packet to be declined. 87.113.130.148 (talk) 09:36, 28 January 2012 (UTC)

However as a word of caution, I will repeat what Nimur said which is that you never quite know when things are going to go wrong. For example, I once had an annoying problem with occasional data corruption for transfers between a Nvidia Nforce 4 ethernet adapter and some sort of Marvell PCI gigabit adapter using SAMBA (Windows file sharing on both sides). Transfers between the Marvell and another Marvell (on the same computer, it was dual GbE); the Marvell and a Intel gigabit ethernet adapter; and the Nvidia and Realtek PCI express ethernet adapter seemed fine AFAIK (although I didn't test that hard). I never worked out what was wrong and newer drivers etc didn't seemed to help although possibly turning off jumbo packets did. Eventually the problem seemed to go away, again I didn't know why. IIRC in the early 2000s or so, there was some crappy Realtek Windows fast ethernet drive which screwed up the checksums so was also a cause of frequent corruption. (Realtek fast ethernet adapters had a particularly poor reputationt, their gigabit ones seem a bit better.) Over the internet, things fail much more often. A simple search will find plenty of discussions of corruption over HTTP or FTP even though these use TCP. IIRC we had someone with this problem a few days ago although it's possible the file size was borked in that case. But I've definitely had the problem myself before when the file size was right but the file corrupt. From my experience, it generally gets worse when you download in a single file multiple chucks (using resume or similar, not a file split into parts). I'm guessing transparent proxies also increase the risk of something going wrong. Of course you can usually save such files via bittorrent or eMule or other P2P, which hashes the file in small parts. Nil Einne (talk) 14:47, 28 January 2012 (UTC)

And I'll just link to these :) Wikipedia:Reference_desk/Archives/Computing/2011_June_6#long-term_media_storage_and_compatability, dvdisaster, rsync. ¦ Reisio (talk) 07:31, 28 January 2012 (UTC)

Key loggers on smart phones

A few months back I read about smart phones being used for keystroke logging. I didn't see anything at the time that suggested that it was very easy to do "in the wild" where conditions are variable. And also from what I read, it takes a great number of keystrokes to get anything reliable.

I've taken a part time job at a call center and this tech is one reason why they don't allow cell phones in the call center. They fear that we might be stealing credit card numbers with this logging software and a smart phone. I'm not looking for anything in regards to the legality of any of it and I'm not looking to actually do it. I'm just curious as to whether it's possible to do this with just a small amount of time (before some supervisor notices your smart phone on your desk) and in conditions that are less than ideal. Thanks, Dismas|^(talk) 04:29, 28 January 2012 (UTC)

With a wireless / Bluetooth transmitter (or if there's an even slightly less-than-really-well-administered wireless router connected to the local network) you wouldn't even have to have it on your desk, or even particularly near your desk. Of course they'll also have to keep you from having physical access to the computer ports and/or from bringing in things you can put into them (and things that you could hide things you could plug into them), from installing software on the computer, from altering the BIOS configuration, from bringing in portable audio recorders, portable video recorders, from having anything resembling normal internet access, etc.. It'd be quite a job, but arguably you don't need to be using your mobile phone at work anyways. There are much simpler and less risky ways to obtain such data than getting a job at a call center. ¦ Reisio (talk) 07:39, 28 January 2012 (UTC)

I realize there are much simpler ways. After all, I still have access to pen and paper. And by the way, these are thin clients and are pretty well locked down as far as installing anything. Dismas|^(talk) 13:54, 28 January 2012 (UTC)

wifi printer setup problem

Hi. I am trying to set up an epson stylus nx230 printer, which I bought today. It works fine on a USB cable, but nothing seems to be able to detect it via wifi. My PC (windows 7) can't see the printer, and neither can my ipad2, with epson's own printe app. The precise error that the ipad gives (after "searching for printers . . ." for a minute or so) is "Cannot find printer. SSID ThomsonA0E284. Check the network settings for this device, and the scanner . . . ". googling gives epson's utterly useless support site. Various FAQs suggest altering the printer's control panel, and my printer doesn't have one. Am I being stupid and missing something obvious? Robinh (talk) 08:13, 28 January 2012 (UTC)

Might need it connected to a computer with the drivers/software via USB to configure it. ¦ Reisio (talk) 08:53, 28 January 2012 (UTC)

Thanks for this Reiso. The PC used the CDRom that came with the printer; no luck. The ipad2 used epson's own app. No luck. I'm beginning to suspect that there is something very basic I don't understand about wifi printing. For example, could this printer work wirelessly in on an island with electricity but no wifi internet? Robinh (talk) 09:06, 28 January 2012 (UTC)

That's pretty unlikely. :) Where'd you get the SSID 'ThomsonA0E284'? Realtime support: http://webchat.freenode.net/?nick=epsonWless&channels=##windows ¦ Reisio (talk) 09:25, 28 January 2012 (UTC)

Software writer?

I am looking for information on "RecordDISCXXX" an entry I found in my computer register that I have never heard of. An Google search gives reference but I cannot get info as the web pages seem to want to download software only, I am not willing to take the risk. I am looking into the plethora of names that interlink up the command line of who wrote what and who is hiding behind which umbrela company and what old progs become subsumed by others.Icanthavemyname (talk) —Preceding undated comment added 09:33, 28 January 2012 (UTC).