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February 16

Did IBM Watson take the lead tonight on Jeopardy! ?

I missed the show. Thanks. 76.27.175.80 (talk) 01:24, 16 February 2011 (UTC)

Usually the relevant articles for such things are updated quite promptly with current events: See Watson (artificial intelligence software). Short answer: it ended the first match with over three times the amount of the next contestant, although it botched the Final Jeopardy question (In the category "U.S. Cities", it answered "Toronto"), losing only $947. -- 174.21.250.120 (talk) 05:24, 16 February 2011 (UTC)

Error while calculating Windows Experience Index in Windows 7

I am using Windows 7 and when I try to calculate the WEI, I get the following error message:

Cannot complete assessment. The assessment or other operation did not complete successfully. This is due to an error being reported from the operating system, driver, or other component.

I tried updating all drivers by going to the Device Manager. I also do not have Kaspersky antivirus installed (I learnt from a forum discussion that Kaspersky might be the cuplrit). But I still have the error. Due to this error, I am not able to apply the Aero effects onto my system. How can I calculate the system rating? Please help me. Thank you very much. —Preceding unsigned comment added by 125.16.180.5 (talk) 07:51, 16 February 2011 (UTC)

extract text from PDF

Hi I have a PDF file with a lot of tabular, columnar information. There are columns with characters and some with numbers. I would like to extract all of this into text, but when I choose 'save as text' it saves all the text separated by spaces... so that's pretty useless because I don't know which column it belongs to. I was thinking about selecting a column at a time and copy/paste but the alt-left-click doesn't allow scrolling down the file. Any ideas on how to get the PDF into fixed-format text or even better, comma-delimited? Sandman30s (talk) 07:54, 16 February 2011 (UTC)

It depends on how the PDF was created. Sometimes it records structural information, sometimes not. My first run at it would be to use a PDF->HTML converter that would make column extraction easy. Failing that, I would look for or write some software that would guess at the columns based on where the bits of text are. --Sean 14:11, 16 February 2011 (UTC)

If the text is separated into columns by spaces, would the Text-to-Columns feature in Microsoft Excel work? Kingsfold (Quack quack!) 14:49, 16 February 2011 (UTC)

I suggest opening the PDF in Inkscape. You will likely have better access to getting the columns of text out of the text box itself than the document viewer. -- kainaw™ 14:57, 16 February 2011 (UTC)

If it is not too many tables I usually copy-and-paste the text into Notepad. Then it is easy to see if there is really a tabular structure to the text. If there is, and you are not lucky and get tab characters between the columns, I usually remove any spaces within fields manually (for example, "United States"-->"UnitedStates". Then, I copy and paste the data into Excel, where the "import text" feature comes up automatically and I can choose space as a column separator. Not too elegant, but always fastest for small operations. It's hard to standardize this in any case as the structure of PDF documents can differ a lot. Jørgen (talk) 20:25, 16 February 2011 (UTC)

Thanks for all the help. I managed to find a PDF to Word converter and got it into a program-readable CSV thereafter. To Jørgen, no, the file was way too big to use the method you described. Sandman30s (talk) 10:27, 17 February 2011 (UTC)

VuDroid

The pdf pages overlap vertically. Can you help me? --83.103.117.254 (talk) 08:03, 16 February 2011 (UTC)

Probably the best thing to do is to file a bug with that project here. You should link to or attach the document in question. --Sean 13:58, 16 February 2011 (UTC)

GPS

I have planned to buy the GPS monitor shown here.I am not subscribed to any GPS service or satellite etc. Will the monitor still work for me ? ( I am in south of (India's) Punjab)  Jon Ascton  (talk)

You do not need to subscribe or pay for GPS service. The satellites are already in orbit, and they broadcast their signals free of charge. Some users, particularly the military, use different signals (or, the same signals with different decoding technology that isn't available for sale to the general public), to obtain better quality position information - see military GPS signals - but anyone can receive all of the signals. Nimur (talk) 17:46, 16 February 2011 (UTC)

I don't believe that the miltary get better positional information - this was the case with Selective availability but this is no longer used. --Phil Holmes (talk) 10:31, 17 February 2011 (UTC)

However, some GPS mapping providers charge for updates to maps when new roads are built, and for live traffic information, to help you avoid the jams. Others do the routing on a central computer, instead of on the device (Android Maps for one). For any of these services, you'll need to take out the subscription. CS Miller (talk) 19:30, 16 February 2011 (UTC)

How does IBM's Watson choose the categories and dollar amounts on Jeopardy?

I haven't been able to find any answer or reference for this question, so hopefully someone can provide the answer or direct me to the right resource. Watson's algorithms for answering the questions themselves have been nicely discussed on many sites, including IBM's own Watson site and the recent PBS NOVA special. However, I haven't heard any explanation of how Watson chooses which category to select, nor how Watson chooses the dollar amount to select within the category. Is Watson choosing by itself? If so, how? Or is a human "behind the scenes" making the selections for Watson? Similarly, how is Watson choosing the dollar amounts to bet in both Double Jeopardy and Final Jeopardy? The amounts that Watson bet on the show last night were very strange--almost random, and not something that a human would choose. Just curious if there was some sort of coded-in strategy for this aspect of the game. --Zerozal (talk) 17:43, 16 February 2011 (UTC)

All the public information about Watson is available from IBM at the IBM Watson website. I haven't watched all the videos explaining how he works, but I would posit that estimating confidence in an answer is easy, based on statistical results of earlier answers - so to pick a category, Watson can select the category he is most confident in. Or, Watson may use an elaborate game theory model to defer using "preferred" categories until a more optimal time. Nimur (talk) 17:49, 16 February 2011 (UTC)

I looks like they do some basic game-theoretical stuff. If my calculations based on the information at j-archive are correct, Jennings' total score could have maxed out at $41200, had he wagered everything (and gotten it right, which he did), and Watson's wager was such that, had it lost, he'd've had totaled $41201. Of course, the reason Watson had to wager a wacky number to make that come out right was because it had a wacky score from Double Jeopardies where it wagered wacky amounts. Probably that's because they've worked out some kind of function that takes as input the Watson's estimated likelihood of getting the answer right, and then they round it to the nearest dollar. Paul (Stansifer) 02:35, 17 February 2011 (UTC)

This post describes Watson's wagering strategies for both Daily Double and Final Jeopardy questions. --LarryMac | Talk 17:59, 16 February 2011 (UTC)

Thumbnail images in Windows Vista

My laptop runs Windows Vista, and whenever I want to view photos in Thumbnail mode, I am unable to see previews; I have to open each individual file to see my pictures. Do I need to change a setting to see the previews? Alternatively, is there a third-party application that I can install? Currently all I see is a generic view of an island. Hemoroid Agastordoff (talk) 17:55, 16 February 2011 (UTC)

In "Folder options" (the view tab), the option to "Always show icons, never thumbnails" needs to be unchecked. Showing thumbnails can slow down the browsing of folders, so this option is provided for slow computers. Dbfirs 09:45, 17 February 2011 (UTC)

Thanks, Dbfirs, you've made my day ! Hemoroid Agastordoff (talk) 15:31, 17 February 2011 (UTC)

Standby

Resolved

Is there a way to make a computer running Windows 7 go into standby or some other similar mode where the hard drive and processor etc power down, but keep the screen on and displaying something? 82.43.92.41 (talk) 23:00, 16 February 2011 (UTC)

No, the processor is needed to generate the image you see on your screen. Looie496 (talk) 23:12, 16 February 2011 (UTC)

(ec) No. Even with fancy ACPI power management technology, and even with smart graphics processors, the CPU is still required to put pixels to the screen (or to command the GPU to do it by proxy). There are no "personal computer"-style machines that can power down the CPU and still keep an image on the display screen. Some e-book readers may have a capability to do what you want. Nimur (talk) 23:13, 16 February 2011 (UTC)

Ok 82.43.92.41 (talk) 23:15, 16 February 2011 (UTC)

Well, technically, most new monitors display something when they are powered on, but do not receive a signal. For example, something like this: [1]. decltype (talk) 09:36, 18 February 2011 (UTC)

True; technically, most monitors contain a fully configurable and programmable computer inside them, too: a Video Display Controller resides on the monitor-side of the connection, and buffers, and then decodes, VGA or DVI or HDMI signals. Ironically, this means that in a modern PC, using a VGA connection to an LCD monitor, the signal is digitally generated by software on the CPU, copied to RAM, sent through a peripheral bus like PCIe, sent to a GPU bus controller, copied to video ram, converted to an analog signal by a RAMDAC, sent in analog format to a video controller, re-digitized/resampled, re-buffered, and finally displayed on the screen. And this doesn't even count video/GPU processing. Every single pixel of every frame is passed through this pipeline when the CPU is in control of the screen buffer. Most users, running most operating systems, on most hardware, are not able to micromanage the entire video-pipeline, but conceivably, a skilled programmer with the appropriate driver toolkits and reasonably configurable hardware, could subvert the "conventional flow" to perform a task similar to what the original questioner wanted. Frankly, such technology baffles me, and I wouldn't want to be the person who has design it. Nimur (talk) 22:02, 18 February 2011 (UTC)

Actually this hits something I was thinking of. Doesn't this really depend on the monitor not th computer? I don't know if such a monitor exists but I could imagine one with a USB connection and some software on the PC you use to tell the monitor what to display in standby mode. Nil Einne (talk) 13:21, 19 February 2011 (UTC)

February 17

Generic DVD/RW software for Win XP

I've just got myself an Acer Aspire netbook, and am trying to persusade it to recognise an ancient external Freecom classic series DVD/RW. I know I looked some time ago for software/drivers for this, but couldn't find any - eventually, I found a generic driver somewhere, but I haven't a clue where. Does anyone know where I can find one?

The netbook recognises the DVD writer as a CD drive only at the moment, but I've definitely had it working before - unfortunately, this was on my desktop PC, which seems to have given up the ghost, so I can't see what software I was using :( AndyTheGrump (talk) 01:51, 17 February 2011 (UTC)

Scratch that: It seems to recognise the DVD/RW now, or at least, it reads DVD's ok - I think I'll need to find DVD writing software, but that is less urgent. AndyTheGrump (talk) 02:45, 17 February 2011 (UTC)

One free option for the software is CDBurnerXP (if you're using pretty much any version of Windows) which burns onto CDs, DVDs, etc.  ZX81  ^talk 12:15, 17 February 2011 (UTC)

Another alternative is Infrarecorder, which is free. -- Finlay McWalter ☻ Talk 15:20, 17 February 2011 (UTC)

Thanks, I'll take a look at both - Infracorder sounds familiar, that may have been what I'd been using previously. AndyTheGrump (talk) 20:54, 17 February 2011 (UTC)

There is also ImgBurn. Reviews are here: http://www.techsupportalert.com/best-free-cd-dvd-burning-software.htm 92.24.182.65 (talk) 21:45, 17 February 2011 (UTC)

How do I save an LUA file as an LUA file in Vista?

I want to edit a small lua file for an RTS mod that I play, but Vista brings up an error message something along the lines of "cannot specify path or make sure specific path is correct" every time I try to save the edited file. Even when the file is unedited it won't let me save. I just want to edit the lua file and save it, how can I do that? --Ye Olde Luke (talk) 04:47, 17 February 2011 (UTC)

Are you able to get to the Save As dialog where you can specify a save location? Does it allow you to save in the Documents folder or on the desktop? I know lua files often have to be saved in a sub-folder of the game's application folder (sorry, the technical term has deserted me!). Vista can be very protective of folders under Program Files, and I often had to save my addon files elsewhere, moving them to the correct folder as an admin user afterwards. --Kateshortforbob _talk 13:18, 17 February 2011 (UTC)

Drive size increases after copy then delete files

Okay. Just make it simple with a small example. This morning I move 25 GB of data from D: to E: before formatting D:, to get rid of some garbage files created by the Windows System Image that I cannot see (even if system hidden file are shown). After everything is done, I move those data back. Now the E: drive size increases by 47 MB. 47 MB is not too serious for me, but I really want to know where and why it is gone. Not only this morning, I have seen that phenomenon for several years w/o a reason. Only when I format the drive, the wasted space created by deleting files is restored. If I remember correctly, this does not happen on drive with FAT32 file system. My flash drive for example; its size always changed to 4096 bytes each time I deleted all data on it. -- Livy the pixie (talk) 08:12, 17 February 2011 (UTC)

If I were to hazard a guess I would say that the space was used up by Windows Advanced Indexing which didn't clean up the newly allocated space once the files were deleted again. You can turn indexing off if you really want, but I wouldn't recommend it as that feature is used to improve the speed and stability of your system. It's also possible your page file could have increased in size. Sandman30s (talk) 10:38, 17 February 2011 (UTC)

No, I use no page file at all. I would like to used raw RAM because I think it is faster, and my computer RAM is large enough to be used without page file. I have heard a thing or two 'bout the Indexing thing but maybe I need to study it further. Just googling around, but 'till haven't found the answer yet. Btw, anyone can try copy about 1 GB data or larger to a drive and then delete it to see the result. -- Livy the pixie (talk) 10:55, 17 February 2011 (UTC)

The Master File Table has a 1-kilobyte entry for each file on the disk. It's expanded as necessary and (I believe) never shrunk. If you moved 48,000 files or so, that could be the explanation. Later files created on the volume will reuse those MFT entries. -- BenRG (talk) 11:20, 17 February 2011 (UTC)

Personally I think you should not worry about any of this. In an era when 2TB drives cost US$80 or US$90, why get all OCD about the issue to the point where you are actually formatting drives to try to reclaim an amount of space that is tiny by today's standards? You should also use a page file, by the way; it shouldn't slow down your system in your case. Comet Tuttle (talk) 17:42, 17 February 2011 (UTC)

Windows XP had/has an annoying habit of discarding perfectly good pages when the system is idle even when there's no memory pressure. I often had the experience of leaving my computer to get a cup of coffee, returning, and having to wait several seconds while the stupid thing paged in the application I had just been using. I disabled the swap file and the problem went away, with no apparent downside. This might be fixed in Windows 7; I don't know because I've never attempted to use a swap file in Windows 7. RAM is cheap too... -- BenRG (talk) 21:12, 17 February 2011 (UTC)

This page at Coding Horror hosts part of a fierce debate on this issue. One somewhat obscuring fact is that Windows 7 is a very active disk cacher and whatever RAM you have that is unused will rapidly be used for disk cache, which may make measurements harder. Personally I would always choose to have a disk cache, even a 1 byte disk cache, if it were feasible, because I would prefer to never ever seen an "Out of Memory" error again in my whole life; having disk cache on simply prevents this. (Obviously by growing my 1 byte page file to whatever size was needed, when it was needed.) And if you've got so much RAM, your OS should never be hitting the page file anyway. If, as you say, the OS behaves itself well. Comet Tuttle (talk) 21:25, 17 February 2011 (UTC)

I disabled it because I hate the way Windows manage page file. If you had 2 GB RAM, it set the page file to 2 GB, and if you had 4, it set the page file to 4 (logically it must set the page file smaller because you have more RAM). I encounter no issue on my desktop with 4 GB RAM but my laptop with 2 GB RAM crashed when I opened 8 → 10 tabs on IE silmutaneously, so I was forced to set it to 1 GB. -- Livy the pixie (talk) 04:07, 18 February 2011 (UTC)

It doesn't necessarily follow you need a smaller page file if you have more RAM. In fact, logically, if you have more RAM, there is more stuff that may be worth swapping out so a larger page file makes sense Nil Einne (talk) 13:17, 19 February 2011 (UTC)

Windows has two sizes for files - the actual number of bytes in the file, and the space used on disk. Depending on file, sector and cluster sizes there can be quite a discrepancy. If a disk has 1024 byte clusters, then a 1025 byte file will consume 2K of disk space, even though Windows will still report that it is a 1025 byte file. If you delete that file, then the free space on the drive will be (previous free space + 2K). --LarryMac | Talk 20:22, 17 February 2011 (UTC)

That's true, but it can't explain the missing 47 MB. -- BenRG (talk) 21:12, 17 February 2011 (UTC)

There's a general trend in the design of computer systems to build things that have more and more nice properties (reliability, good performance in corner cases, etc.), at the expense of predictability. FAT32 is not a journaling file system, so it's simpler in behavior, but breaks more and worse. Paul (Stansifer) 20:53, 17 February 2011 (UTC)

Almost forgot. If you deleted a single 7.8 GB DVD9 ISO image, the drive size increased only by a few bytes. But if you deleted several thousands files with total size of 500 MB, the drive could waste up to 10 MB (Approximately. The point is that the more files are deleted, the more space is wasted. The wasted space does not depend on the file size, but on the number of files). Oviously 47 MB is too tiny by today standards, and I do not format the drive to recover it. Just because I want to know why it vaporizes into thin air. -- Livy the pixie (talk) 04:07, 18 February 2011 (UTC)

If it's ~1K per file, then it's probably the MFT (see above). -- BenRG (talk) 06:33, 18 February 2011 (UTC)

It sounds logical. But are you sure later files created on the volume will reuse those MFT entries? -- Livy the pixie (talk) 08:08, 18 February 2011 (UTC)

WYSIWYG Wiki Editor

Is there WYSIWYG Wiki Editor that can be used in a web browser to create/edit, even in offline and later submit to Wikipedia?

There was a big effort to do something like that in browser Javascript but I don't know its current status. I just write wikitext in emacs (i.e. so I see the markup, not wysiwyg) and it works fine. Wysiwyg is overrated unless you have no experience with wiki markup. 71.141.88.54 (talk) 11:41, 17 February 2011 (UTC)

Wikia.com uses a wysiwyg editor. I hate it. I refused to use wikia until they offered an option to turn off the wysiwyg editor, allowing users to use wiki markup. -- kainaw™ 13:40, 17 February 2011 (UTC)

Kaspersky Internet Security fouling up my devices

I recently plugged my Archos 28 Internet Tablet into an XP computer running Kaspersky. Kaspersky decided to wipe all the data from the device because it was allegedly a virus. I got it all restored, but it started behaving rather oddly; the folders wouldn't display a "folder" icon but instead a 'unknown file type' one. They'd always open in a new window. Now it won't let me add or delete files on other systems because the disk is "write protected," and something similar's also happened with a SanDisk Cruzer Blade USB stick I've been using.

What can I do? 122.174.98.39 (talk) 11:57, 17 February 2011 (UTC)

Well, an obvious thing to try is to uninstall Kaspersky and install some different antivirus software, and see if that fixes your problem. List of antivirus software is a good starting place. Comet Tuttle (talk) 17:39, 17 February 2011 (UTC)

Graphics/visualization question: converting vector field samples into continuous streamlines

Say you have a 2-D vector field sampled regularly at grid points. How do you convert the samples into continuous streamlines(?) for visualization? Thanks in advance. --173.49.19.81 (talk) 12:57, 17 February 2011 (UTC)

Are you asking for a "general solution" or a specific software program that can do this? Here is software to draw arrows in FORTRAN90, in MATLAB using the quiver command; in the free software GNU Octave you can also use quiver. If you want streamlines you must numerically integrate the ordinary differential equation whose gradient is expressed by the vector-field; and iterate over initial-values for each streamline you want to solve. This is a bit tricky, because in pathological cases the solutions will be unstable (and streamlines will cross - which is an unphysical result). For this reason, you should not use a simple forward-difference integrator (like an euler method) - though you can try, and see if it works. In MATLAB, you can use ode23 or the other sophisticated higher-order Runge-Kutta methods to stably integrate most vector fields. In FORTRAN-90, you can use your favorite numerical solver code, such as this RK-45 solver from Iowa State University. To make matters more complicated, if (as you say) you have sampled the vector field (and cannot explicitly calculate it at every point) you must interpolate the values between sample-points so that an integrator can solve the streamline. The method you choose for interpolation can influence stability and convergence, not to mention physical interpretation of the streamline. If you are lucky enough to have MATLAB, you can use the Streamline program to perform all of these steps for you. I do not believe GNU Octave supports this command yet ((streamline) is reported "unimplemented" still). For obvious reasons of complexity, it is non-trivial to implement this in general. Nimur (talk) 20:47, 17 February 2011 (UTC)

Valve holder tax

In the Radio receiver design#FM vs. AM article there is mention of an "valve holder tax" that the UK goverment imposed. What were the reasons behind this tax?, and time period? I did some net searches, but no qualified answer were found. Electron9 (talk) 13:12, 17 February 2011 (UTC)

The reason behind this tax was simply to raise revenue. No different from the Hearth tax, and Window tax. People who choose to have more than fire place, or think they 'need' more than one window, or even have a radio with more than one thermionic valve socket, obviously have more money than sense! Therefore, their government obliges them to pay even more for the said items. With the money so collected, those who have the onerous duty to run the country, can then spend the money more wisely - on such things as foreign visits, commissioning statues of themselves and cultural enriching things that the tax payers themselves are not capable of appreciating. Germany imposed a similar tax.Vacuum_tube#Other_variations. Simple really.--Aspro (talk) 20:55, 17 February 2011 (UTC)

Which time period?, and how muchdid the goverment charge?, used other countries? Electron9 (talk) 10:17, 18 February 2011 (UTC)

Aspro: do you have any evidence that the UK valve holder tax was intended to raise revenue and not e.g. to fund radio services?

I can't find any evidence that there was a valve holder tax in the UK. Googling "valve holder tax" returns only pages that scraped that Wikipedia page. I found a discussion that explained that sales tax was payable on valves for home use in radios but not for commercial/industrial use in other products; this is consistent with having a tax on finished products but not on raw materials or components (the current UK value-added tax uses a different system to the same end.)[2] However, early 20th century taxation policy may not be well documented online, so it's possible the tax did exist for a while.

Regardless of the valve-holder tax, the UK had a radio tax in the mid 20th century (1922-71) which was used to fund the BBC: you had to buy a radio licence to own a radio in the UK. In the earlier years, a licence for a home-made radio was more than that for a pre-built radio bearing the BBC brand (again this may have been transformed into memories of a tax on valves). There was an additional tax payable on the licence from 1957 to 1964 which went to central government, but most of the time all the money went to the BBC. The licence is briefly mentioned in Television_licence#United_Kingdom but my main source is[3]. --Colapeninsula (talk) 10:38, 18 February 2011 (UTC)

Home brewed radios were certainly more expensive to build from purchased parts. One had to buy the components as if they were spares (and also pay purchase tax on the higher prices). Even from a wholesaler willing to give a discount off the list price, it would still cost a little bit more. Still, if one just bought the valves, most of the other bits could be scrounged or made in garden shed for naught. --Aspro (talk) 18:15, 18 February 2011 (UTC)

Crossword puzzle generators

Resolved

Hi, I'm wondering about crossword generation software, preferably for Windows (but Linux is fine too, as long as it has a GUI) and definitely not online. I used to have a program on my old Mac OS 9 machine (archaic, I know), that did exactly this but I can't remember what it was called. It updated the puzzle as you were typing, so you could see the layout of the puzzle while you were making it. Thanks :) XRDoDRX (talk) 14:45, 17 February 2011 (UTC)

I use Crossword Compiler. I think it only has British English but I could be wrong and it might not matter that much depending how you want to use it. There are others available if you search the web.--Shantavira|^{feed me} 16:17, 17 February 2011 (UTC)

I found a free one called EclipseCrossword. Sometimes I wish Windows software was sorted into packages, it would be much easier to find the good stuff. XD --XRDoDRX (talk) 03:22, 20 February 2011 (UTC)

Keyboard/start-up problem

I have a Dell Latitude D620 laptop and run Windows XP that requires me to do a control-alt-delete after a start-up. The problem is that when I press the control-alt-delete buttons, nothing happens and I can't get use the laptop. Obviously, I'm on another computer now. Does this mean that I have a bad keyboard, or is there something else I can try? Thanks for any help. 71.125.146.152 (talk) 16:05, 17 February 2011 (UTC)

A few things to try

• Do the other Ctrl-Alt-Del keys work? Either the left or right Ctrl and Alt keys, and either the Delete or NumPad Del keys will normally work.
• Does an external USB keyboard work?
• Do the NumLock/CapsLock keys work?
• Try pressing F6 after the BIOS screen clears; you should drop into the Windows Boot Loader; does Ctrl-Alt-Del reboot the laptop here?

CS Miller (talk) 16:22, 17 February 2011 (UTC)

Thanks for the quick reply. I tried those options, and none worked. I was finally able to get through to my employer's IT people and was told the keyboard is not functioning because I can't even start up before Windows begins running. They're sending me another. Again, thanks for your help.71.125.146.152 (talk) 16:53, 17 February 2011 (UTC)

What you can try is to power off the PC. Take out the battery and the cord and hold the power button for a minute. That resetted the keyboard for me when it was not working. --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:14, 17 February 2011 (UTC)

This sounds like you've run into a rather common problem with the Dell D-series laptops...I did tech support for C-Series and D-series laptops for a couple of years, I've seen that issue countless times. The problem is that the keyboard connector on the motherboard is just badly engineered and the cable will occasionally come off. The easy fix is to remove the keyboard (there are a couple screws marked with "K" for keyboard on the back, just unscrew these and you can lift off the keyboard), then unplug and firmly reseat the keyboard cable. If you haven't sent it off to your support people yet, that's definitely something you should try. -- Ferkelparade π 09:18, 18 February 2011 (UTC)

IBM Watson

Is IBM Watson an OS or just a program running on an OS? --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 20:56, 17 February 2011 (UTC)

We have an article on Watson (artificial intelligence software), although it doesn't answer this question directly. Personally, I'd say that Watson is an application running on specially configured hardware, and most likely running a customized version of whichever OS IBM typically supplies with the Power7 hardware. --LarryMac | Talk 21:04, 17 February 2011 (UTC)

This type of diagram may be misleading you.

I thought WATSON was an OS since only an OS has direct access to all the hardware components --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:11, 17 February 2011 (UTC)

The article does answer this directly — Watson runs on the SUSE OS. It's an application. Why would you assume Watson needs "direct access" to any hardware component? Comet Tuttle (talk) 21:12, 17 February 2011 (UTC)

Damn, I read right past that at least four times. My bad. --LarryMac | Talk 00:01, 18 February 2011 (UTC)

Because than it can harness the raw power of the CPU and graphic chips (assume WATSON has one) --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:15, 17 February 2011 (UTC)

I think that diagrams like the one to the right (which I found in our operating system article) may be misleading you a bit. It's true that an OS is allowed to execute certain CPU instructions that an application is not allowed to execute, but the CPU still directly fetches each instruction in the Watson code and executes it directly, and stores the results directly into memory. Being an OS wouldn't speed up Watson any more. Comet Tuttle (talk) 21:34, 17 February 2011 (UTC)

If the machine has special hardware designed for your application (which Deep Blue certainly did, but I don't know about Watson), one does normally need kernel privileges to use it, but the usual practice is to write most of the software as a normal application, except for a small device driver that runs in the kernel and passes application data to the hardware and vice versa. -- BenRG (talk) 22:55, 17 February 2011 (UTC)

Operating systems don't possess any inherent power that applications don't have. They can deny powers to applications (if the user so desires); this is useful for security. But it's best to think of the operating system as an abstraction layer: it allows each program to run as though it were the only program running on the machine, and without having to know the details of the particular machine. Even though the Watson software was purpose-built for one machine and that machine had only one use, it turns out that writing software in this way is much easier than writing it without an operating system, because the imaginary simple machine that the OS presents to the applications is nicer than the real machine. Paul (Stansifer) 05:11, 18 February 2011 (UTC)

There's nothing magical about operating systems. They're just programs like applications are. The only technical difference is that they run directly on the hardware, but it's actually technically possible to run any program directly on the hardware. Today's computers are so complex that writing an application running directly on the hardware is quite difficult compared to writing one running on an operating system, but in the past, it was common to write custom programs that ran directly on the hardware. The answer to the original question is that WATSON is most probably an application running on an operating system. JIP | Talk 08:15, 18 February 2011 (UTC)

A technical whitepaper is available from IBM at http://ibm.com/watson - you may need to create a free IBM-login if you don't already have one. Watson is written in Java - so technically, IBM Java Runtime Environment is the "operating system," though the IBM JVM resides on top of IBM Linux on IBM Power7-750 systems, with a variety of other IBM and free/open-source software. For example, the Hadoop and Apache UIMA technologies make the system work as a whole. With clusters of computers, it's often difficult to describe "operating system" in terms that the average PC-user will quickly understand (because - it isn't exactly clear if the "computer" is distinct from the "ensemble of computing nodes" - especially if each node is a fully-capable computer on its own). If I were to describe the OS, I would say it is "Apache httpd, plus the IBM J2EE environment." I would not include Linux as a description of the operating system of Watson, because he could be trivially ported to any other computer platform that supports Apache and J2EE. In the case of the machine we saw on television, "Linux" is really just a very sophisticated device driver for a handful of CPUs and a little bit of RAM; the operating system is the Java environment that harnesses hundreds of Linux devices and assigns tasks to them. Nimur (talk) 16:53, 18 February 2011 (UTC)

WATSON interface

What does IBM WATSON GUI looks like? Also I read in the comment that WATSON crashed during the games. Is this true? --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 23:13, 17 February 2011 (UTC)

There may not be one. Watson's job is to consume a chunk of text and produce another chunk of text. Programmers are used to working with command line programs, and Watson's task fits that ideally. Of course, there's a great deal of complexity between input and output, and we can only speculate on all of the diagnostic and control tools that the engineers had access to. A software project like Watson probably has a single large piece of software and a cloud of (partially) independent tools. Each of these can be operated by a human, and probably some of them allow a person to drive the whole thing in a simple way (useful if some person comes visiting and wants to see a demo, instead of the charts and graphs and benchmarks that the engineers have been staring at for weeks as they struggle to improve the system).

I hear the rumor that Watson kept on crashing during the game, also. It seems odd to me because IBM's researchers clearly know how to write software, and the problem probably lends itself to a (relatively) stateless (and perhaps even nicely modular) design, which would make it easy to write reliable code. But I don't know anything about the problems they faced. Paul (Stansifer) 05:39, 18 February 2011 (UTC)

Where does that rumor come from? IT seems like no one outside of IBM would actually know that. APL (talk) 06:13, 18 February 2011 (UTC)

It might be a throwback to the Kasparov match. One of the criticisms of Deep Blue was that the programmers manually altered the system between matches to incorporate fixes to defects discovered during play. The fact that the rumor takes off could be feeding off of that, with the thought that "well, the computer didn't really do it on its own, it needs constant attention of people to work". Sort of a pro-human/"humans *aren't* obsolete" ego boost. Pretty much the same reasoning behind the criticisms that the match wasn't fair because Watson got the clues in the form of a text message instead of having to do audio processing/OCR of the monitors. -- 174.21.250.120 (talk) 18:04, 18 February 2011 (UTC)

I don't think it's a rumor. My understanding is that the PBS people filming the game encountered frequent delays because of problem with a computer. They incorrectly assumed that it was the IBM machines running Watson that was at fault, but later clarified that it was actually the computer that passes the questions to Watson. Predictably, the press ran the story without doing any research into whether it was true or not. On a side note, the cluster running Watson is built from Power 750s. If they are like earlier models, restarting them after a crash is not a trivial matter as it is with PCs, its an approx. 30-minute affair due to diagnostic checks. Rilak (talk) 07:27, 18 February 2011 (UTC)

It's also worth noting that IBM software is, unlike many commercial "consumer" tools, usually subject to extremely high uptime requirements. Now, Watson was a research project, but he was still designed in the same environment. During my (brief) time at IBM, I recall the motto, "high performance, high uptime, high availability," in reference to our computers and our engineers. You can read about High Availability Services at IBM's website. Mean time between failure is often quoted in years or even decades. (Again, let me re-emphasize - this is not your average Windows PC). It sounds very dubious that the software, hardware, or anything else, would crash during the game show. What I might believe is that "performance degradation" occurred as a result of software or hardware error, but IBM Tivoli restarted the derelict server software. (Another thing I learned from IBM is that there's no such thing as a "crash" or a "failure"...) Nimur (talk) 16:35, 18 February 2011 (UTC)

Regarding the GUI, it is probable that Watson uses the IBM variant of the Eclipse platform. IBM uses Eclipse to develop and to deploy almost all of its software. It is very likely that an Eclipse plugin communicates to a set of IBM server-utilities to monitor status. Nimur (talk) 16:39, 18 February 2011 (UTC)

February 18

Good Alternatives to file and folder shortcuts on a USB flash drive?

When trying to keep track of hundreds of files on a USB flash drive, I usually organize the files into a tree structure with folders named after topic or theme. I use quite a lot of folder and file shortcuts back and forth between the various folders.

It works fine until I plug my portable USB drive into another computer where it suddenly no longer is called "E:\", but instead "G:\" or "I:\" or whatever. This renders all my file shortcuts useless. ;-(
Of course, the same thing also happens when I copy a directory tree to another disk.
(I currently use WindowsXP but I would like the solution to be platform independent).

Could you please give me some advice or ideas to how I might solve or avoid this problem?
--Seren-dipper (talk) 13:42, 18 February 2011 (UTC)

The easiest thing to do might just be to a pick a drive letter that's not in use on the computers you usually use and then change the USB drive to that letter (Control Panel -> Administrative Tools -> Computer Management -> Disk Management or just Start->Run->diskmgmt.msc). Of course that won't work if you go to a computer that has the drive in use, but if you use the same computers regularly this could be the easiest solution.  ZX81  ^talk 14:41, 18 February 2011 (UTC)

Or you could use subst to create a substitute drive letter of your choice on the computer which maps to the usb drive letter. There's a nice gui version here which is portable too so you could keep it on your usb drive ready to use on any computer. Both methods probably require admin privileges on the computer you use them on, so might not work on public or restricted computers. 82.43.92.41 (talk) 14:48, 18 February 2011 (UTC)

Great answers! Thank you!
--Seren-dipper (talk) 19:46, 18 February 2011 (UTC)

How may I "update" file shortcuts?

Now, do you have any suggestions for how I may "update" drive letter and/or path for all file and folder shortcuts when (or after) moving a directory (including all subdirectories) into a new drive and/or into another location within the directory tree structure?
--Seren-dipper (talk) 19:46, 18 February 2011 (UTC)

Identifying disks on Linux, similar question to the above

The question above about USB drives on Windows made me think that the same kind of thing would happen on Linux. Linux identifies drives in the order it finds them, assigning them labels such as /dev/sda, /dev/sdb and so on. My current computer has two internal hard drives, so a USB drive would be /dev/sdc. But suppose I added a third internal hard drive - this would cause USB drives to become /dev/sdd instead, causing the ready-made mountings in /etc/fstab to become useless for this purpose. Is there some way in Linux to mount filesystems by the actual disks they're on, not by the device Linux happens to assign them? JIP | Talk 14:32, 18 February 2011 (UTC)

On my (Ubuntu) system, there are automatically constructed symlinks in /dev/disk/by-label/, so that you can talk about your partitions by what they're labeled, rather calling them /dev/sd?. Ubuntu also automatically handles mounting (also using labels) in some magical fashion I don't understand, so I've never had to touch my /etc/fstab. Paul (Stansifer) 15:13, 18 February 2011 (UTC)

In Fedora and Redhat, I have /dev/disk/by-id, by-label, by-path, and by-uuid. So, there are many options for identifying a disk other than using the sdx option. However, as Paul stated, Linux auto-mounts removable media by itself, so there is no need to add USB drives to fstab. -- kainaw™ 16:15, 18 February 2011 (UTC)

Minor quibble: I don't believe "Linux" (the kernel) performs any auto-mounting. gnome-volume-manager, which is running by default in Ubuntu and many other Linux distributions, auto-mounts disks. If you use Kubuntu, a different mount service manager may be running; and if you use a different version of Linux, you might not have any auto-mounting functionality at all. Nimur (talk) 16:43, 18 February 2011 (UTC)

As Kainaw notes, partitions can be mounted by UUID. They appear in /dev/disk/by-uuid, and you can (I guess, I've never used that method) specify that explicitly in fstab. An alternative is to use the UUID= syntax in fstab, which does the same thing. So my own fstab looks like this:

    # boot partition 
    UUID=40cdfe04-298a-4ac6-919c-11c88e451a06 /               ext3    relatime,errors=remount-ro 0       1
    # swap
    UUID=8c3f96ba-e5f6-4a52-9162-fe33a7d077b2 none            swap    sw              0       0

This survives all kinds of disk rearrangements. Because the UUID corresponds with the partition (not the physical disk) one can dd a drive's contents to a bigger drive, unplug the old, and the system boots as before, with no change to fstab. -- Finlay McWalter ☻ Talk 17:05, 18 February 2011 (UTC)

The manual page for mount(8) recommends the UUID= method over the /dev/disk/by-xxx method. -- Finlay McWalter ☻ Talk 17:13, 18 February 2011 (UTC)

Installing Fedora 14 with every single package?

Suppose I were to install Fedora 14 64-bit version with every single package that comes on the install DVD. Roughly how much space would that take on the install partition? JIP | Talk 17:14, 18 February 2011 (UTC)

My vague guess/memory is in the 6-8 gb range. The dvd is something like 3.3gb but a lot of the content is compressed. You'll want to install more stuff beyond the dvd, though, and have some space left for swap and user files. 71.141.88.54 (talk) 11:25, 19 February 2011 (UTC)

OK, so that probably won't be a problem. I have a 80 GB root partition, which I'm currently only using about 8% of. All of my personal user files are on a separate partition, which is far larger. There's yet another partition for swap. I figure it shouldn't be too much of a problem to upgrade to Fedora 14 by reformatting the root partition but keeping the other partitions intact. JIP | Talk 14:25, 19 February 2011 (UTC)

Keep in mind that you might clobber various kinds of configuration files by doing that, or you might have to re-install programs that you forgot about. I'd advise having a good backup of the root partition before doing the upgrade. My usual way of upgrading an OS is buy a new hard drive, install OS on it from scratch, copy user files from old drive, and put the old drive in a drawer just in case (more backups are always good). 71.141.88.54 (talk) 20:05, 21 February 2011 (UTC)

Best choice of writeable DVD disc types

I'm in the process of moving a writeable DVD drive from another old computer to the old computer I use. It will be able to write DVD+RW, DVD-RW, and DVD-RAM. Which of these discs would be the best choice to buy and use please? I am going to verify what is written to disc, and it would help if any faults could be corrected. Thanks 92.28.240.53 (talk) 17:15, 18 February 2011 (UTC)

Our article DVD+R lists a few ways that DVD+R is allegedly superior to DVD-R, at a cost of being able to store slightly less data. Comet Tuttle (talk) 17:53, 18 February 2011 (UTC)

I agree with above statement. If in dault, read the specification. Of course don't forget the "made in China" warning label :-) Electron9 (talk) 18:17, 18 February 2011 (UTC)

Electron9's being amusing, but he's correct that there's cheap media and more-expensive media, and I've seen a lot of people online blame cheap media for discs going bad within a short time. Note that our various articles about DVD recordable formats say DVD-Rs and DVD+Rs may have a lifespan as short as a couple of years. I also note that our DVD-RAM article has claims of superior reliability and length of data storage compared to DVD-R and DVD+R, but I have no experience with DVD-RAM, and that article does need some more citations. Comet Tuttle (talk) 18:44, 18 February 2011 (UTC)

I didn't ask about DVD-R or DVD+R, but DVD+RW and DVD-RW and DVD-RAM. 92.29.119.194 (talk) 23:45, 18 February 2011 (UTC)

It is claimed that DVD+RW has better error-tolerance during the read and write process; for example, see this review from Tom's Hardware. In practice, the distinction is moot. Use caution with DVD-RAM, because while many DVD drives can read the entire set of DVD-R, DVD+R, DVD-RW, and DVD+RW, fewer drives can read DVD-RAM. Nimur (talk) 00:04, 19 February 2011 (UTC)

(ec) Pressed DVDs and DVD±R[W] all use the same on-disc format for the recorded data. DVD–RAM is completely different. You can't make DVD-Video discs using DVD–RAM. I think that it's far superior as a sector-addressable optical disc format, but the discs are more expensive (you do get more for the price) and most DVD drives can't read them.

I think it's true that DVD+R[W] has a more robust method of storing information in the pregroove than DVD–R[W]. But that information is only used when burning the disc. It has no effect on the readability of a 10-year-old disc, but it might have an effect on its rewritability, I suppose. The user data is encoded in precisely the same way on pressed DVDs and DVD±R[W]. DVD+R[W] does not have better error correction for your data, just for the pregroove information.

When using rewritable DVDs as sector-based media with a filesystem like UDF, I think DVD+R has advantages over DVD–R because it's erasable in smaller blocks (?). If you're writing and erasing whole discs at once, there's no advantage.

The Wikipedia article is obviously a mess. I'm pretty sure that DVD+R doesn't have a smaller capacity than DVD–R by design. Capacity varies slightly between manufacturers, and some random person stuck a couple of random blank discs in their drive and put the reported capacities in the article. -- BenRG (talk) 00:13, 19 February 2011 (UTC)

I don't think that's correct. Unlike with CDR, DVD-R and DVD+R commercial disc capacities hardly vary at all AFAIK, at least for single layer variants. DVD-R discs are very slightly larger (~4489MiB or 2,298,496 sectors) than DVD+R (~4483MiB or 2,295,104 sectors), however the capacity differences are so small as to be irrelevant. See also [4] Nil Einne (talk) 13:04, 19 February 2011 (UTC)

To give more context, I'm only interested in data disks, for archiving. So I want something that will still have the data after ten or twenty years in a drawer, and which will be readable when put in most computer DVD drives. What is best for that? Thanks 92.29.119.194 (talk) 00:41, 19 February 2011 (UTC)

I recall DVD-RAM being better than DVD+RW but it's also way more expensive last time i checked. Read technology specifications to know for real. Anyway DVD+R is still better than DVD+RW due chemical stability. As for physical discs, Verbatim is likey the most reliable. And extremely vary of rip-offs etc.. very common these days! with products that have the logotype and look of the original but lack any quality. Infact make a software setup so that you can use the writer feature that measure the resulting margin which ends up on the discs. To improve storage you should eliminate the oxygen, humidity and heat. Nitrogen and humidity absorbing materials can be helpfull in this aspect. Electron9 (talk) 04:18, 19 February 2011 (UTC)

Is DVD-RAM readable by most computer DVD drives? Thanks 92.15.16.146 (talk) 11:07, 19 February 2011 (UTC)

No, see DVD-RAM. 71.141.88.54 (talk) 13:51, 19 February 2011 (UTC)

I also have to caution you that even a DVD-RAM disc may not be readable after twenty years in a drawer. The question of backup media reliability over the long term is pretty much a FAQ here at RD/C and it'd be nice to have the backup article expanded to explicitly discuss the expected lifetime of the different common media used for backups. Our article Digital preservation is sort of all over the place but it touches on a few related topics. Comet Tuttle (talk) 00:56, 22 February 2011 (UTC)

Strange connectivity issue

When I use my router's ability to change its MAC address ('MAC address clone'), I lose my connection to the internet until I set it back to the old default address. However if I connect through a different router or even directly through my computer (all of which have different MACs), there doesn't seem to be a problem. WHy is this? 72.128.95.0 (talk) 20:15, 18 February 2011 (UTC)

I'm assuming you're using a cable internet provider? My guess is that the MAC address of your alternative router and your PC are also logged by your provider as legitimate addresses, but that the new address you change you router to isn't.--Phil Holmes (talk) 10:50, 19 February 2011 (UTC)

Have you tried unplugging the router and plugging it back in, with the new MAC settings? I've had issues with cable modems freaking out when the MAC address of the connected device changes but the link stays steady. Replugging the router or rebooting the cable modem might solve the issue... 151.151.16.7 (talk)

Long term data storage

Some what to do with the DVD question previously, If i took various kinds of data storage (CD's,DVD's, floppys, USB drive etc and any others ppl think off) put them in a box and left them at say standard room conditions. (So there not in perfect isolation but then there not being kicked around and left in the sun). Which would "hold on to" its contents for longer? ie if i came back in 10 years time and assuming i had kept the various drives/drivers etc, would any of them be expected to of had some of the data "disappear"?--86.145.90.102 (talk) 23:17, 18 February 2011 (UTC)

I beieve that if stored in room temperature in sealed cases I think the will work perfectly after ten years. Even more if you put it in a vacuum I would think. General Rommel (talk) 23:27, 18 February 2011 (UTC)

Have a look at the Library of Congress CD-R and DVD-R/RW longevity project, part of the Digital Media Preservation project. Disc coatings can peel and crack. In this thorough report, Longevity of CD Media - Research at the Library of Congress, quantitative failure rates are published. Nimur (talk) 23:34, 18 February 2011 (UTC)

Here's a similar question from the archives which has some interesting information 82.43.92.41 (talk) 00:01, 19 February 2011 (UTC)

For data that are actually high-value, you need not only media to store them on, but procedures for verifying them, copying them to new media, switching from older media to new ones (e.g. to maintain compatibility with new machines), and so on. Maintaining a long-term data archive will end up being not so much like keeping a bunch of books in a vault, but rather like running a scriptorium. --FOo (talk) 07:01, 19 February 2011 (UTC)

February 19

What do you do?

OK, computer experts. I am looking at my Windows 7 box right now as it displays a dialog box telling me my computer is low on memory and I should "Close programs to prevent information loss". The mouse cursor has disappeared, the keyboard does nothing, ctrl-alt-del doesn't display the Task Manager, and the computer appears unresponsive and inert ... except that the hard disk light on the tower flashes several times per second. The light is off, I'd estimate, 90% of the time in any given second, and the other 10% of a representative second, it's on (distributed throughout that second in a number of flashes, if I'm making sense.)

I've seen this phenomenon many times before on XP boxes, a few times on Vista boxes, and this is the first time on a Windows 7 box.

The question I put to you all is: What do you do when your machine locks up except that the hard disk light keeps flashing? Do you express faith in protected memory and the OS by waiting for an hour? Two hours? Begging for your mouse cursor to return? After all, maybe it's hitting the page file a lot and it's all fragmented, or something, and the computer will come to its senses any second now. Or do you swear explosively after sixty seconds of inactivity and cold boot the machine? Comet Tuttle (talk) 00:20, 19 February 2011 (UTC)

When I have a computer that misbehaves in any way, I usually format its boot partition and re-install a fresh copy of an operating system I trust on it. (This can include Windows XP, for some computers). Installing Windows XP usually takes around 15 minutes - faster than diagnosing and debugging any type of system corruption. (Customization and program-installation can take longer, but not "much"). For this strategy to be effective, you need to design your computing infrastructure such that catastrophic-loss-of-operating-system has minimal or zero impact on the integrity of your important data. You can accomplish this by robustly backing up important data, and/or placing data on separate disk partitions and separate physical media. Also note that this doesn't fix "broken" (or obsolete) hardware. Nimur (talk) 00:28, 19 February 2011 (UTC)

To answer the question directly, I cold-boot the machine, and then I contemplate the fact that I have been asking the machine to do more than it is capable of (because of its limited memory), and I think about whether it would be better to (a) reduce my demands, possibly by removing cruft that is running in the background (b) add more memory, or(c)get a new computer. Looie496 (talk) 06:17, 19 February 2011 (UTC)

Technically, protected memory isn't relevant here; it's having a journaling filesystem, which ensures that the disk can always be easily restored to a consistent state. Of course, you have to hope that the OS hasn't just put things into a consistent-from-the-file-system's-point-of-view state, but broken-from-the-user's-point-of-view, but I think that rarely happens. Paul (Stansifer) 16:34, 19 February 2011 (UTC)

How can my organization's editor, or I, do minor updates and corrections on your posted biography of me (Amory B. Lovins)?

This question isn't related to computing, moving to Wikipedia:Help desk. JIP | Talk 20:21, 19 February 2011 (UTC)

The new links are:

• Current Help desk link (will rot in a few days); archived link (will work after a few days); permanent link (should work as long as Wikipedia works)

--Teratornis (talk) 03:43, 20 February 2011 (UTC)

Glasses less 34

How does glasses less 3d works? I can't find an article. --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 08:01, 19 February 2011 (UTC)

There's autostereoscopy. 88.112.59.31 (talk) 08:26, 19 February 2011 (UTC)

The history of branch prediction

Wikipedia's article on branch predictors says that the IBM 7030 (of late 1950s vintage) did static prediction. I did some research, searching the web, books, and papers for any computer predating the 7030 that did any form of branch prediction. I could not find any. So my questions are: Was the 7030 the first computer to predict the outcome of branches? If the 7030 was the first computer to predict branches, then did the idea of predicting branches predate the 7030? Thanks in advance. Rilak (talk) 08:15, 19 February 2011 (UTC)

STRETCH was a stupendously aggressive design with many "firsts", not all of which worked. If you look at the references to the 7030 article, in particular the online book "Planning a Computer System - Project Stretch", you might be able to find more info about the branch predictor. 71.141.88.54 (talk) 10:50, 19 February 2011 (UTC)

I can't find anything earlier than 7030 that claimed to use branch prediction. Note that earlier computer systems, like IBM 7090, were not pipelined CPUs (and as far as I can tell, did not have a memory cache, either). So there would be zero benefit to speculative execution in those computers. IBM 7030 may have the point for first branch prediction, but System 360 definitely gets a lot of extra points for effective implementation of register renaming, register-forward-passing of preliminary results through the pipeline, successful dynamic branch prediction / speculative execution, and a lot of other features of "modern" CPU pipelines. (Tomasulo algorithm is named for one of the chief architects of System-360). Now, if you want to "extend" the definition of branch-prediction to try and apply it to some very primitive systems, you might be able to - but to meet today's definition, you'll need to find a CPU with a staged pipeline deep enough for speculative-execution to have mattered. Nimur (talk) 15:52, 19 February 2011 (UTC)

I suggested looking at that particular book because I think it might contain info about the design process of the 7030 pipeline and branch predictor, and might mention whatever antecedents (if any) that were known at the time. I looked briefly at the book a long time ago and thought it was interesting, though I'm afraid I don't remember enough about its contents. It just seems like a reasonable first place to try. 71.141.88.54 (talk) 21:41, 19 February 2011 (UTC)

where to find someone who is interested in making something new easily

Resolved

I'm not an active programmer, but I know how a common protocol works, and by inserting two lines into the protocol, you could get a different, really interesting protocol. I'd like someone to do this for me, they can publish the results too, under their name. (They can keep maintaining the project, too, if they want,, which would add to their portfolio and might help them get jobs, etc). I just want use of the resulting protocol. (I've already checked with others, and my changes do work). How would I go about finding such a person? Anyone who knows C++ and can recompile an existing project with a few lines of changes in a few minutes, could do this whole thing in 20 minutes, and it's interesting and cool. Thanks. 109.128.192.218 (talk) 10:24, 19 February 2011 (UTC)

If it's that simple, why not describe it here. 71.141.88.54 (talk) 10:39, 19 February 2011 (UTC)

Because that won't get anyone to make it? You'll just say the same thing others said: "yeah, that would work and it's pretty cool." Maybe I should make a programming contest, where everyone has 20 minutes to do it, and whoever's I judge best gets a prize of $50 and the right to say they won the contest. Ironically, the same people who in this way would end up working for free (i.e. all but the winner), probbaly wouldn't do it for $50 outright - especially the most talented one, the one who wins. So, I can't use $50 to get a copy of my working protocol outright, but I can use it to get a BUNCH of different solutions, all working, and all but one of them made for me for free... Boggles the mind. 109.128.192.218 (talk) 10:51, 19 February 2011 (UTC)

$50 for 20 minutes is probably pretty attractive to student programmers or the like. You could post an ad on craigslist, or to some programming forum as you suggest. But, I agree that most programmers with any experience wouldn't participate in such a contest for an uncertain shot at the prize money. They'd only do it if they were guaranteed payment on completion of the task. The reason I suggested posting the idea here is so that programmers here could then tell whether the idea made sense. It's often easy to overestimate the usefulness or underestimate the difficulty of some programming idea, especially for a non-programmer. 71.141.88.54 (talk) 11:11, 19 February 2011 (UTC)

There's no question if it works. Why don't you email me at M8R-0489c01@mailinator.com (made just now for just this purpose, don't worry about spam) and I'll respond with 2 lines, then you can come here and post that you agree it works. I've had enough confirmation that it works, now I'd just like to have it done. 20 minutes. for anyone who can recompile an existing project with a few lines of changes in a few minutes. That's not me. 109.128.192.218 (talk) 11:17, 19 February 2011 (UTC)

Why are you being so secretive? Just post it here. Or anyway, say what protocol or project it is. 71.141.88.54 (talk) 11:19, 19 February 2011 (UTC)

Because then no one will do it. But fine, I'll post it here if anyone here makes a promsie on their mother's life that if they agree with me that it works and can be done in a few minutes, they will do it and host the resulting project somewhere. We're talking a couple of minutes here, for someone who meets the criteria that they can "recompile an existing project with a few lines of changes in a few minutes". Tell me that you meet the criteria and make the promise, and I'll do it. 109.128.192.218 (talk) 12:01, 19 February 2011 (UTC)

just a reminder, that my question is "where to find someone" who is interested in that. IRC? Some special site? Where. 109.128.192.218 (talk) 12:14, 19 February 2011 (UTC)

Why on earth would anyone make such a promise? They don't even know what project it is. If it's something like Firefox, it takes hours to build from source. The reason I suggested that you post the idea here is so people can decide for themselves if it's interesting enough to spend any time on. Right now there's no evidence that it's even interesting. And it's not even clear what you're asking--someone is supposed to patch some C++ program, recompile it, and send you a compiled binary? Don't you know better than to run binaries from strangers over the internet? You don't even say what OS you're using, so any particular reader might have a tool chain for their OS but not for yours. Or wait, you're asking them to fork some existing codebase and maintain a fork for the rest of their lives? Why not just get the upstream devs to take the patch? Anyway, these guessing games are not very interesting. If you want to hire a programmer, I already suggested craigslist.org. 71.141.88.54 (talk) 12:25, 19 February 2011 (UTC)

You could always learn a programming language and do it yourself, which would probably be the best option if you want to keep whatever it is you're doing up to date and just how you want it. 82.43.92.41 (talk) 12:34, 19 February 2011 (UTC)

If you're as secretive and spend as much time trying to convince people it's a good idea and very easy but they need to make obscure promises before you even tell them what it is, I don't know if there is anywhere you can find someone willing to do it for $50. In fact considering the reason you say you don't want to tell people is because they won't do it if you do tell (not say because you're scared they'll steal the results and not give you credit which you don't even seem to care about), the only logical conclusion most people are going to make is there's either something dodgy which is why you're being so secretive or you're just wasting their time. On the other hand, if you actually tell people what they want to do when they ask without asking for obscure promises, and it really is as simple as you say, I'm sure you'll find someone somewhere like craiglist that's already mentioned who'll be willing to do it. It may not be everyone who reads your request but I don't see that matters. Nil Einne (talk) 13:29, 19 February 2011 (UTC)

Fine, I'll tell you

ugh. Fine, I'll tell you. Target: latest version of Debian, against which I've never programmed. Just make a private and public key using pgp etc. Then download source code to any bittorrent client and modify it thusly. In the part that checksums bad data you got from other peers, before you throw it out if it failed checksum, do one more thing: write it out to a file, and check to see if it was signed by keypair you made. (you only use the public key for this). if it was signed, then it means it's a new .torrent2 file (name of our protocol) and you start that in another copy of your client, as well as telling peers connected to you that you have it, giving it to them when they want it, etc. Even though it failed the checksum, you treat it as if it had passed it.

That's it. There are a couple of implementation details that will take the rest of the 20 minutes. (or, if you're not an 31337 hacker, the rest of your couple of hours.)

What does this do? This replaces an RSS server for a series of torrents. If you know you want to get the next episode, which doesn't exist at the time of the torrent creation (so you can't possibly include any reference to it in a normal .torrent file, since you can't checksum it, it's from the future) - normally what would happen then is that users have to wait until that file actually exists, and then download another torrent for the new file in a totally non-p2p way (RSS, direct http, etc). A torrent2 just lets you put that into the final chunks of the file. The implementation details I mentioned include checksuming just the first part of the file, not the extra payload (treated as 0's when checksuming the original files). Also torrent creation, which means creating a file with extra chunks at the end that later will deliver the next torrent file, and for the checksuming, treating those chunks as zeros.

The idea is that all these users are already in a p2p network, why should they have to do a direct file download for the next part of the series (which doesn't exist at time of torrent creation) - why not just use the same network they're in?

The protocol piggybacks on the bittorrent protocol. Thus, there are two layers: bittorrent layer, bittorrent2 layer.

At the bittorrent layer, this is what happens. Nobody is a seed, because nobody has the last chunk. Nevertheless, the users get to 99%, and, lacking any seeds, just stay in a network waiting for the last chunk.

At the bittorrent2 level, when they reach 99% they already decide to write out the original file, and they use the file's checksum (assuming 0's for the last chunk). They are done with the original file download and just waiting for the next torrent.

This way there doesn't need to be an RSS server or direct downloads. With trackerless torrents, the original server can be long gone. When the next episode exists, the 'server' can just join the same network as a client, but with the difference that it has the private key and can create, distribute and initiate the next torrent2 for the whole network waiting for it. (If you feel uncomfortable about automatically starting the torrent2 of the file from the future, as a security measure, the next torrent2 doesn't have to actually start, it can just be written out and the user could be prompted to see if he wants to start it. Either way, you save having to do a direct, centralized download of the next torrent2 file.)

All this, I swear to you, can be done in 20 minutes by an 31337 Unix hacker in a contest setting. Yes, it might take you a couple of hours, but this is super easy.

Now queue all you people saying "yeah that'll probably work" and is obviously super-simple, and no one doing anything about it. I'll pay $100 to the first person who tells me they will do this by midnight UTC (about ten hours from when I post this) at my e-mail address listed above, M8R-0489c01@mailinator.com and will update the status here to show that the prize has been taken. If they don't deliver I'll repost tomorrow. They can also use it on their portfolio. Seriously, aren't there any 31337 hackers here who want $100? This is not a contest: this is just you. It's obvious you can do the above in a few hours, if not 20 minutes. Write me. 109.128.192.218 (talk) 14:12, 19 February 2011 (UTC)

It's like, I'm handing someone a portfolio and a job worth about $80k/yr (that they will get by having this on their portfolio.) Yet I expect no one will take me up on in it. 109.128.192.218 (talk) —Preceding undated comment added 15:12, 19 February 2011 (UTC).

Another word of advice (I was thinking this before but didn't think you'd respond so didn't bother). It's good you dropped the secrecy surrounding the idea but if you want to get people to drop everything do work for you which has to be completed in 10 hours, when you haven't come to any sort of prior agreement for them to be available at your beck and call, you may find they'll need more evidence they'll get paid, and a random IP and throw-away email isn't that. Definitely if someone handed me an alleged portfolio and job worth $80k/year but they didn't tell me who they are I wouldn't be particularly interested. Nil Einne (talk) 15:23, 19 February 2011 (UTC)

um, in case it wasn't clear the job isn't from me. I'm saying, if you're a member of my target audience (basically, anyone who is a good coder, understands what I wrote, and is used to compiling on Linux), and you're not working for $80k yet, having a project like this (creation of an a successor to the torrent protocol that obsoletes the need for an rss server pounded by all the people listening to it), you will get an $80k job pretty easily. I am not offering that job. I'm offering 100 bucks. If you read my offer, I didn't say anything about payment up front. I said "first person who tells me they will do this by midnight UTC". Obviously I can pay you before receiving your ocde, if you say you've done it. There is no "alleged portfolio". Your portfolio is whatever you create for me. It's your own work. I don't know what you think a portfolio means, but that's what the word means. This is an investment in your future, plus 100 bucks from me, if you will agree to do this. I can make payment before you deliver any of the code to me. Anyway, it's certainly more interesting than whatever else you could do for the next twenty minutes (if you're a 1337 Unix hacker) to ten hours (if you're just a good programmer). No one has mailed me yet. By the way, the mail is to protect me from spam from crawling bots, I can give you my real email address if you mail me. 109.128.192.218 (talk) 15:53, 19 February 2011 (UTC)

Also, the reason the deadline is today is because the right person can do it in 20 minutes, and the almost right person can do it in a couple of hours, but the wrong person can string me along for weeks. It's as though I needed a 12-word sentence translated from French to English. First I would ask the reference desk, and if it required 20 minutes of work and no one would do it, I would pay someone. But I would not give them weeks and weeks to get back to me on that. Come on. In weeks and weeks, I can learn French myself, using online dictioaries, etc etc. Forget it. 109.128.192.218 (talk) 16:02, 19 February 2011 (UTC)

1. Go to any of the freelancer sites on the web.

2. Describe the project and make clear that payment is upon completion You'll get better offers than $50/20 minutes. —Preceding unsigned comment added by 212.169.182.73 (talk) 15:37, 19 February 2011 (UTC)

I've used those sites, and I guarantee you nobody even understands what I'm asking, and even if they do they would try to deliver it in Visual Basic. Unlike here, where everyone understands what I'm saying, agrees it's super-fast, everyone is a competent coder, but won't do it anyway, depriving themselves of having it on their portfolio to show prospective future employers. 109.128.192.218 (talk) 15:53, 19 February 2011 (UTC)

Many of us volunteer at the reference desk because we are here to help people find references about computers. If we were seeking commercial opportunities, our time could be spent more fruitfully elsewhere. In any case, let me make a few comments about your idea:

• This project will take much longer than 20 minutes. Even somebody with specific experience in a particular bittorrent source code would not be able to correctly make the modifications you suggest in 20 minutes.
• You are suggesting a modification to an existing standardized network-application protocol. How will that work? Who will connect to your (now-incompatible) bittorrent client? Your software is not standalone - to succeed, it will require aggressive marketing to acquire network effect critical mass; otherwise, you simply have created an incompatible bittorrent client.
• Are you sure you thoroughly understand the way bittorrent protocol works?
• Are you sure you understand the risks of accepting binary data from a peer-to-peer network that explicitly failed an identity-verification checksum?
• Do you realize that many Bittorrent sourcecode is free and open-source, and that you could make these experimental modifications yourself? In fact, there is no barrier for anyone to perform these modifications - except that they aren't very useful.

Hopefully your project will find success, and best of luck implementing it. Nimur (talk) 16:04, 19 February 2011 (UTC)

(EC) I think you're missing my point. What I'm saying is that whether it's an $80k job or a $100, no one is going to take up an offer without some evidence the person behind it is serious. People will be more concerned when it comes to an $80k job offer but in both cases they'll expect some evidence. Also from what I've seen no one has agreed your job is super fast. And I suspect many don't agree that doing the work you propose is guaranteed to lead to an $80k job offer. I would note no one ever suggested the RD as a good place to look for someone to do this for you, in fact most people suggested other sites. What we have suggested is 1) We may be able to tell you whether your idea is really as easy as you suggest (personally I don't think it is but I don't code so...) 2) Given the way you've approached things here, it's not surprising if you're having problems getting help elsewhere. As a final suggestion (i.e. I won't respond further), I would suggest you look for a freelancer site which allows you to specify what language you want and also that you avoid telling people they'll be guaranteed a $80k job from doing your work (since most people are likely to laugh at the idea then ignore your proposal). If you don't get any offers, perhaps it's because what you want isn't as easy as you suggest so your money isn't really worth it? Nil Einne (talk) 16:14, 19 February 2011 (UTC)

Thanks for your feedback. My original question is where to find someone who is interested in making this, freely and open-source, for everybody, just because it is interesting. I would just be one of their users. This is in no way a commercial enterprise or relationship. This is not some get-rich-quick scheme or something. It's get-not-bored-for-a-very-short-period-of-time scheme. Like, get not bored for 20 minutes type deal. Let me give you my thoughts: - "This project will take much longer than 20 minutes. Even somebody with specific experience in a particular bittorrent source code would not be able to correctly make the modifications you suggest in 20 minutes."
The modifications I suggest by definition are not "correct", they are a hack. That's because the bittorrent protocol can have extensions, and I'm not suggesting we use one, just butcher the protocol so that it isn't bittorrent anymore. Further, almost all of the action is out of the executable, it is just a couple of lines of script you execute, the scripts just call gpg or something, which is totally stand-alone. Look, check out the old CLI (command line interface) code for Transmission:https://trac.transmissionbt.com/browser/branches I can find the places to change code myself in a couple of minutes. Really, this is not that much work.
- "You are suggesting a modification to an existing standardized network-application protocol. How will that work? Who will connect to your (now-incompatible) bittorrent client? Your software is not standalone - to succeed, it will require aggressive marketing to acquire network effect critical mass; otherwise, you simply have created an incompatible bittorrent client." Sorry, you misunderstand. I'm not trying to "succeed". bittorrent2 has nothing to do with bittorrent - it's totally incompatible. Any bittorrent user would NEVER be able to finish downloading from bittorrent2, since it will never accept the garbage data that bittorrent2 users pass around for the final chunk. (they accept it because it is signed properly). So, it has really nothing to do with bittorrent. You're mistakenly thinking that this thing requires some kind of adoption or something. It doesn't. It's a one-off project that can be done in 20 minutes. For example, you don't even have to change the public and private key (for example, include either in the original .torrent2 file, etc). It's a one-off hack that's interetsing but takes 20 minutes.
- "Are you sure you thoroughly understand the way bittorrent protocol works"
Yes.
- "Are you sure you understand the risks of accepting binary data from a peer-to-peer network that explicitly failed an identity-verification checksum"
It's not executable data, as you're implying. It's like this: the person who signed it is the person who made the .torrent2 The only difference is that instead of including the data and checksuming it on the spot, you include data from the future and instead of checksuming it, use signing to verify it later. If I don't trust the torrent file that is going to get signed by the creator of the torrent2 later, why would I trust it if it were in a traditional torrent, checksummed then? It doesn't make sense. Besides, there's no trust involved. It's not an executable file.
- "Do you realize that many Bittorrent sourcecode is free and open-source, and that you could make these experimental modifications yourself?"
Absolutely, but it sure as shit wouldn't take me 20 minutes, unlike a Unix hacker, an 31337 one. The reason I'm asking you guys to do is cuz' you can do it super-fast, and I can't. No, the modifications are in no way user except to me and others. All of whom would install the bittorrent2 client you fork from a bittorrent client, since it's the only one right now that supports the bittorrent2 protocol. Even if nobody else ever downloads it, it's still there on your portfolio. You can even publish a specification for it, if you really wanted. At the moment this is a 20-minute hack that I'm saying is worth it in terms of your portfolio. If you judge that sinking an additional 10 hours into a spec and more options (like creating torrents that include a new public key somewhere, so that it's not "hard coded" into the implementation) you can always do it. If not, you can always drop it. Really, we're talking about twenty minutes of YOUR time, and we've been arguing about it for hours. That makes sense for me, since I couldn't have done it in that time, but it doesn't make sense for you, since you could have. 109.128.192.218 (talk) 16:23, 19 February 2011 (UTC)

I guess people here don't like my attitude or suggestion. I personally thought that the offer of laying out exactly what you need to do as a programmer to have this interesting project done and on your portfolio was pretty cool, a very fair offer. If I were a programmer, I would jump on this chance, just as I have jumped on similar chances in my own field. But, I understand that you all disagree with me, and think that I'm trying to take advantage of you through my approach and attitude. So we'll just have to disagree. 109.128.192.218 (talk) 16:27, 19 February 2011 (UTC)

Please understand, some of us are "unix hackers" and are able to evaluate the technical merits of your suggestion. If you are not a programmer, as you readily admit, you aren't qualified to evaluate the merits of this programming project. Different opinions will surely exist, but it is my solid opinion (founded on years of Unix programming experience with open-source and commercial software) that your suggestions are (1) much more technically difficult than you realize; (2) modifying or "forking" the bittorrent protocol is unlikely to work as a "tracker replacement" technology, as you intend; and (3) your monetary incentives are both small, unguaranteed, and irrelevant to the task of extending BitTorrent. If you are sure your idea will work, here are some suggestions: create a reference draft specification; contact people who are alread developers of open-source bittorrent software (in this era of "social networking", this is trivial); establish yourself and your idea.

With due respect, good programmers are few and far between. Non-programmer "idea-guys" are all too common; they regularly solicit good programmers with "awesome new things," and often tout their ideas as though they've already struck upon the next big gold-mine. Unfortunately, these usually are not fantastic and lucrative ideas - and it's not entirely the fault of the idea-guy. As a non-programmer, you are not qualified to evaluate the technical merits and the challenges of the "brilliant idea" you are suggesting. In lieu of technical advice or BitTorrent protocol details, I suggest you read this book: Crossing the Chasm - Marketing and Selling High-Tech Products to Mainstream Customers - it might be right up your alley, and should help you to appreciate some of the complexities of trying to be an "idea guy" for technology that you aren't really the expert in. Nimur (talk) 16:44, 19 February 2011 (UTC)

Thank you for your detailed critique of my approach. I have taken much away from it, and have marked this subject resolved. There is one misunderstanding all around: I was suggesting a really small hack, not a real specification with real-world acceptance. Truth be told, I can program, and I have programmed. I guess I just need to start coding (I have a Debian machine running in a VM, but have never compiled anything on it.)

But I'm bitter. My lesson is "It takes a lot longer to convince a Unix hacker to become reasonable, than it takes for a reasonable man to become a Unix hacker." 109.128.192.218 (talk) 17:13, 19 February 2011 (UTC)

109.128.192.218 (talk) 17:07, 19 February 2011 (UTC)

After you become a unix hacker, your ideas will only seem reasonable to other unix hackers : ) Nimur (talk) 17:22, 19 February 2011 (UTC)

• My comments: 1) The idea is actually kind of interesting, though if it's worth pursuing at all, I'd give some thought to "doing it right" in the form of some kind of subscription extension to BT trackers rather than this kludge of leaving unfinished downloads for days at a time. Or, using an out-of-band mechanism like a RSS feed may simply make more sense. 2) The 20 minute development estimate is ludicrous; it's possible that someone already familiar with a specific BT implementation and who already had a working build environment for it (this basically means a developer of that specific client) could add and test a patch in a few hours, but a random good programmer who had to download all the code, get it to build at all, and figure out enough about BT to debug the patch, would take a lot longer. 3) I'm no BT expert (I do use it sometimes, e.g. for Linux distros) but my understanding is that BT propagates file blocks between clients in an opportunistic way, i.e. the clients can receive the blocks in any order at all, and they rearrange the blocks into the original order only after all the blocks are received. So when a client receives that "launch bt2" block, it doesn't necessarily have all the other blocks, which means the whole scheme can fail. Even if I saw the patched client successfully download a test file and start the new protocol, I wouldn't be convinced that the patch was reliable until I saw it succeed multiple times on multi-GB files in pieces propagated through dozens of clients that connected and disconnected from the tracker at random. That sort of testing would be quite time-consuming in its own right, separately from development. (Alternatively, maybe I could be convinced through a well-grounded and detailed understanding of BT and the client implementation, but that too would take much longer than 20 minutes to acquire).

  So, overall, I'm not convinced the idea is workable, and even if it is, I'm not convinced it's a sane technical approach, and even if it is, there are various deployment and usability obstacles that others have already mentioned further up (plus others, like how are you going to distribute the public keys?). The OP also seriously underestimates the amount of work it would take to make such a thing. I'd suggest going to some BT developer forum or IRC channel and discussing the subscription idea in more high-level terms, with a considerably different attitude than the one shown here. I can tell you as a programmer sometimes involved in hiring other programmers, that if I saw a hack like that in someone's "portfolio", it would make me less likely rather than more likely to want to hire them. I'd be more impressed by a well-designed and documented extension that made actual sense. 71.141.88.54 (talk) 22:02, 19 February 2011 (UTC)

why would you need the other blocks? These are like, episodes, the idea is that you're interested in starting to download the next episode as well, when it becomes created. It doesn't matter if you haven't finished downloading the last one.... I think if you understand my distinction between the bittorrent and bittorrent2 layers, you'll see that the only way for this scheme to fail is if bittorrent itself fails. it just piggybacks on the scheme, there's nothing special in it. there's no distribution of public or private keys, because this is a one-time hack. What is the salary range of the programmers you sometimes hire, where you would be impressed by a well-designed and documented extension that made actual sense? p.s. the insanity charge is uncontested. —Preceding unsigned comment added by 109.128.192.218 (talk) 00:03, 20 February 2011 (UTC)

I see, yeah, I guess you can have multiple active downloads. But my understanding is you can't actually use the file until BT has decided that the download is finished so it can reshuffle the blocks, so you still have that to deal with. Tell you what, you might enjoy trying to implement the patch yourself. For prototyping / proof of concept, you might try modifying the original headless BT client written in Python, instead of some graphical C++ one that is sure to be a lot more complicated. Also, if it's just for youself and some trusted friends, I don't see much need to mess with GPG. Just include an HMAC authentication tag in the last block with the BT2 info, with a shared secret key that you give to your friends. Python includes an hmac module so it's easy to generate the tag. 71.141.88.54 (talk) 10:06, 20 February 2011 (UTC)

That's a really easy problem to solve if I'm scalpelling the code. Simply, if I have all but the last piece, I jump to the function to put it all together and write the file out (treating the payload chunks as zeros), even though it's not yet time to exit (perhaps making the appropriate change to that function). This is a very easy problem to solve. How much do the programmers who you mention you sometimes hire make? (range). I mean, is it <$30k, $30-$35, $36-40, 41-45, 46-50, 51-55, 56-60, 61-65, 66-70, 71-75, 76-80, 81-85, 86-90, 91-95, 96-100, 101-110, 111-120, 121-130, 131-140, 141-150, 150+? 109.128.201.187 (talk) —Preceding undated comment added 11:22, 20 February 2011 (UTC).

If the problem is so easy to solve I don't see why you are trying to get someone else to solve it for you. I'm not going to discuss programmer salary numbers but you usually negotiate a combination of salary and stock options, trading one against the other depending on your requirements and expectations and the type of company. Also I'm in a geographic region with quite a lot of inflation in both salaries and expenses, so 80k is pretty low for any serious developer in the for-profit sector here, but the rent on a crappy studio apartment with no off-street parking would get you a fairly nice house with a garage in other parts of the country. Nonprofits usually pay less, but can give intangible forms of satisfaction that you might prefer if you don't need the extra money. 71.141.88.54 (talk) 12:32, 20 February 2011 (UTC)

In your geographical area, what is a programmer's salary that is more like "average" (instead of "pretty low") in the for-profit sector in your geographic area? You don't have to tell me what you guys pay, just more like an average in that geographic area... 109.128.201.187 (talk) 17:21, 20 February 2011 (UTC)

Typing "salary survey programmer" into google will find you a lot of sites with that sort of data, probably better info than I could give you. I'm not entirely sure that this is an appropriate subject to discuss on RDC at all, but maybe it is, so if you want to ask such things maybe you should start a separate thread (it's completely off-topic from the BT thing). I will say that when I think of "average programmer" I imagine someone with a lowish-level role in a big group (see code monkey) while "serious developer" would probably be classified as a senior programmer or lead programmer in that kind of organization. 71.141.88.54 (talk) 02:05, 21 February 2011 (UTC)

The use of Eq in Haskell

What is the purpose/function of Eq in Haskell (i.e. what restrictions does it place)? For example, what arguments could be passed to a function of type f :: [a] -> a but not to a function of type f :: Eq a => [a] -> a ? Widener (talk) 10:32, 19 February 2011 (UTC)

The restriction goes in the other direction: Eq is a type class, which means it's a subset of the class of all available types. If you're familiar with Java, Haskell type classes are like Java interfaces. Types that belong to the Eq type class support an equality comparison operation. There is a good Wikibook about Haskell (b:Haskell) that explains all this. 71.141.88.54 (talk) 10:39, 19 February 2011 (UTC)

Oh, sorry, I mis-read your request for an example last night (too sleepy). The most obvious examples of types that don't support Eq are function types. Numeric types support Eq: you can test at runtime that 2+2==3+1. But functions don't support Eq: the compiler and runtime can't in general tell (e.g.) that (\x->(sin x)**2+(cos x)**2) and (\x->1.0) are the same function. So you could not pass the list [sin, cos, sqrt] to a function with your Eq constraint in its signature. Besides the wikibook I mentioned, you might also like http://learnyouahaskell.com . 71.141.88.54 (talk) 22:16, 19 February 2011 (UTC)

Ah, I see. Thanks. Widener (talk) 03:18, 20 February 2011 (UTC)

Would this mean that f :: [a] -> a is a polymorphic function whereas f :: Eq a => [a] -> a is not? (Although I guess f :: Eq a => [a] -> a would still be an overloaded function) Widener (talk) 03:29, 20 February 2011 (UTC)

The case without Eq is called parametric polymorphism, which means that the function is not allowed to change its behavior based on the actual type of a, and the case with Eq is called ad-hoc polymorphism. By the way, you can make any type an instance of Eq by declaring your own instance for it. Instances are supposed to obey the mathematical axioms of equality, but you could write instance Eq (a -> b) where x == y = True; that obeys all of the axioms.

I do not think that instance Eq (a -> b) where x == y = True obeys the axioms for equality. By referential transparency, x==y is supposed to mean that f x == f y for any f. If you let g f = f 1, then sin==sqrt should mean g sin == g sqrt, which is wrong since sin 1 != sqrt 1. Eq is supposed to mean actual equality and not just an arbitrary equivalence relation, as far as I know. To Widener: once your Haskell knowledge has advanced a bit more, the Typeclassopedia (find on google) is an excellent guide/reference to Haskell type classes. But it's a bit too hairy for beginners. 71.141.88.54 (talk) 02:49, 21 February 2011 (UTC)

I would be very careful with the statement that "Haskell type classes are like Java interfaces". The most important difference is that the choice of which implementation to use for an interface is always up to the creator of the instance in Java, but the choice of which implementation of a typeclass to use is always up the the caller in Haskell. For example, integer literals have the type Num a => a; this means that they will produce on demand a value of any type that belongs to the Num type class. It does not mean that they represent a value of some particular type belonging to that type class. The closest analogue of Haskell type classes that I know of is C++ concepts. Unfortunately, concepts were dropped from the standard, so they aren't very useful as an example. -- BenRG (talk) 04:50, 20 February 2011 (UTC)

C++ concepts were certainly inspired by Haskell type classes, so might not be so useful as examples. I agree the analogy with Java interfaces isn't perfect. The main point is that interfaces and type classes both give you a way to have the same operation supported on multiple types with separate implementations per type. I'm not sure what you mean about the choice of implementation being up to the caller. It's true that Haskell typeclasses are "open", which means you can declare a type to be an instance of a class anywhere in the program, if it isn't already one. But I'm pretty sure if you try to do it in more than one place, the compiler will complain. 71.141.88.54 (talk) 07:05, 20 February 2011 (UTC)

What I mean is that generic functions with typeclass constraints are always specialized by the caller. For example, genericLength :: Integral a => [b] -> a can be specialized to the type [Char] -> Integer and called, in which case it must return an Integer, whereas an OOP function with a return type of Integral could return a type of its choice, as long as it implemented Integral. -- BenRG (talk) 08:31, 21 February 2011 (UTC)

Oh ok, yes, that is a noteworthy difference. The comparison between type classes and interfaces is just an analogy, not saying they are the same thing. 71.141.88.54 (talk) 17:29, 21 February 2011 (UTC)

Restrict access to one port

Hello,

I have an area of my site which I only want to be accessed via a certain port that is rotated every week, for additional security. Is there any way that I can do this using a file on my server, say htaccess or something of that sort?--213.168.117.109 (talk) 11:25, 19 February 2011 (UTC)

Which operating system and program are you seeking to rotate? If the O/S is a *NIX, and the program is server in its own right (not cgi-bin), then you could write a cron job that updates the program's config file with the new port, and then uses /etc/init.d/<servername> restart. If its cgi-bin (.htaccess controls the Apache web server, then do the same, but for Apache.

BTW I'm not sure what this gives you, as programs like nmap will probe the server's machine to find all active servers on it, although this is detectable. Programs like pcap/wireshark can also detect when then server is being used, although with modern wired networks the TCP packets aren't sent to the pcap machine. CS Miller (talk) 11:53, 19 February 2011 (UTC)

Nevermind, I figured out that there would have been a problem anyway because of my server's firewall. Thanks anyway.--213.168.117.109 (talk) 12:01, 19 February 2011 (UTC)

I want to run old PC games under Windows 7

Hi, I am posting this on here and the Entertainment helpdesk as it seems to span both - forgive me if that breaks any rules.

I have some old PC games that I used to play under Win95 and Win XP but Win 7 doesn't seem to recognise them - I am now running a 64 bit set-up which probably doesn't help.

My question is, can anyone tell me if I can still buy some of the old games (Monkey Island series; Disc World series; Kyrandia; Gabriel Knight; etc.) but written to run on a modern PC under Win 7? If so, where can I get them?

Hoping you can help. Gurumaister (talk) 11:37, 19 February 2011 (UTC)

You shouldn't really cross-post; I've asked for all replies to come here. If you've still got a Win95/WinXP install disk around, you either make you PC a dual-boot machine, or install a virtual PC on your Win7 install, and run WinXP/Win95 inside it. The latter might be preferable, as the virtual PC tends to emulate older hardware, if Win95 doesn't support your new hardware. CS Miller (talk) 11:57, 19 February 2011 (UTC)

Sure, but before you do anything so drastic, try running the game in emulation mode to see if it works (some do, some do with hiccups, some don't), try out emulators of old systems (like DOSbox) and do a search on Source Forge - SF is basically for people to post their opensource games, but there are many older games there with a cult following and an expired copyright license that people rewrite in opensource code to make them run on newer OSs. TomorrowTime (talk) 12:20, 19 February 2011 (UTC)

Quite a number of those games will work with ScummVM. Specifically the 2D MI, Kyrandia and DiscWorld games. The 2D GK will work but not very well [5]. Note that the 2D Monkey Island games are also available as a remake special edition with high res artwork, see the respective articles. Nil Einne (talk) 12:54, 19 February 2011 (UTC)

I second the idea of using ScummVM for those that are supported by it, and for using, say, VirtualBox with Windows XP on it for the others. --Mr.98 (talk) 13:46, 19 February 2011 (UTC)

Good Old Games might be worth a look too - they take old games, make them compatible with new OS's and sell them as DRM free downloads. Exxolon (talk) 17:14, 19 February 2011 (UTC)

Some old games, like the first X-COM, are sold over the Steam network, and someone took the time to make them work on modern machines. Not sure whether it's the original publisher or a volunteer or someone at Valve. Comet Tuttle (talk) 23:57, 20 February 2011 (UTC)

I don't know about X-COM, but all the old DOS games that I've bought off Steam (Commander Keen, Doom, Hexen, Wolfenstein 3D, etc.) aren't conversions and they're merely bundled with DOSBox as mentioned above. When you run the game from the Steam library it transparently launches DOSBox and then the game.  ZX81  ^talk 01:10, 21 February 2011 (UTC)

Trying to save with Firefox

I get this message:

"name_of_the_file/ga.js could not be saved, because the source file could not be read.

Try again later, or contact the server administrator."

212.169.182.73 (talk) 14:26, 19 February 2011 (UTC)

I've removed my earlier reply because the answer below is so much better! Dbfirs 22:37, 20 February 2011 (UTC)

You are using adblock and it is blocking google analytics. This is a good thing, so don't worry. 71.141.88.54 (talk) 10:47, 20 February 2011 (UTC)

Lock File in folder

can i lock a file in a folder in sd card with a software which can run directly with that software without unlocking? I want to do this silently with cmd command. —Preceding unsigned comment added by 202.56.7.131 (talk) 14:29, 19 February 2011 (UTC)

What do you mean by "lock"? Do you intend to encrypt the file, or to set it as a read-only file? Nimur (talk) 16:14, 19 February 2011 (UTC)

usb

Resolved

If two usb storage devices are connected to a computer via a usb hub and you transfer a file from one device to the other, does the data travel via 1st device -> hub -> computer -> hub -> 2nd device, or 1st device -> hub -> second device? 82.43.92.41 (talk) 16:42, 19 February 2011 (UTC)

The information has to go through the computer. All of the atomic read and write operations are carried out by the computer's operating system. Looie496 (talk) 19:39, 19 February 2011 (UTC)

The reason for this is that USB is set up as an asymmetric host/device (somewhat analogous to client–server) system, rather than a peer-to-peer system. On any single bus, there's only one "host" device that controls all the communication (unless you have some sort of bridge device connecting two buses). -- 174.21.250.120 (talk) 19:54, 19 February 2011 (UTC)

Thanks 82.43.92.41 (talk) 20:25, 19 February 2011 (UTC)

Overheating graphics card?

A friend of mine has problems running some games (Left 4 Dead 2 specifically) so I asked him to download Speccy to get a quick list of all of his specifications, so we could find out what the problem was. This revealed that his graphics card was running at 95 degrees C. Neither of us know a lot about computers, so:

1. I assume this is too hot...am I right?
2. Could this be the cause of the lag? The games run but he's lucky to get 10 frames per second.
3. Is there an easy way to cool this down?

The only thing that's been done to the computer is installing a case fan. The card is an nVidia GeForce 9100. Vimescarrot (talk) 21:31, 19 February 2011 (UTC)

This is not necessarily "too hot." Nvidia cards are notorious for running very hot. 95 celsius is what I consider very hot - but many users regularly report breaking upwards of 100 celsius without problems; the "safe shutdown threshold" on a mobile Nvidia GPU can be 130 celsius in some cases. You can check your graphics driver configuration to see what the default "safety shutdown" temperature was set to. Laptop systems can't provide the same airflow and ambient case cooling that a desktop system can. Finally, the low-frame-rate might not be an "error" - it may just be the maximum performance your system can deliver. The 9100 is not a very powerful GPU - it's at the lowest-end of the mobile editions of the three-year-old GeForce 9 Series (in fact, it used a "stepper GPU" from the 8 series). In general, cooling a modern GPU core reduces bit error-rate; the result is fewer graphical-glitches and fewer required re-transmissions of data from video RAM, resulting in higher performance. Research on GPU soft error rates have shown a correlation to environmental and temperature effects: the G80, used in your Nvidia 9100M, was known to suffer from high soft-error rate. In "video game mode", the errors are usually tolerable or recoverable, but can certainly affect performance and stability. I am not sure if the 9100 system or its software drivers were able to detect and recover from soft-errors. Nimur (talk) 22:11, 19 February 2011 (UTC)

When the temperature rises high (that's pretty high, but shouldn't be fatally so) the first thing that happens is the driver notices and increases the fan speed (a bug in nVidia's driver last year set this wrong, causing GPUs to overheat when the fans didn't step up as they should). If the fan is at max and the GPU is still too hot, the driver should then throttle down the GPU's operating frequency (this temperature is reported to be between 95 and 105 - it seems to vary by GPU, and I don't think nVidia officially advertise what it is). Being in the first condition should make the fan noticeably louder; in the second condition performance will indeed suffer. If this underclocking were occurring, you'd expect to see the frame rate okay for a few minutes of starting the game (from a period of idling at the desktop) and then suffer as the GPU gets too hot and is underclocked. I'd suggest:

• make sure the nvidia driver is the latest, as it controls this kind of stuff
• run the game at the lowest settings (resolution, detail, AA, etc.) you can
• make sure the GPU fan is clean and unobstructed (by dirt, cables rubbing against it) and make sure the air path into and out of your computer is clear.

-- Finlay McWalter ☻ Talk 22:29, 19 February 2011 (UTC)

Thank you both for the help. I think we've got a fair idea of where to go from here, cheers. (No doubt I'll be back in a few weeks when the next problem crops up ;) ) Vimescarrot (talk) 19:17, 20 February 2011 (UTC)

February 20

My CD drive has disapeared

I have an old computer running WinXP SP3. My computer had a DVD ROM drive and a CD RW drive, and both worked fine. Then I replaced the DVD ROM by a DVD RW drive from another old computer. The cables were replaced in exactly the same way, even the jumper setting was the same. I did not touch the CD drive.

Now the DVD RW drive works fine, but the computer does not recognise that the CD drive is there. However the CD drive opens when I press the door button, and during computer start-up its light blinks for a while.

After replacing the DVD drive I mistakenly reconnected the monitor to the wrong plug on the back of the computer, which gave a blank screen. Due to the blank screen I turned the computer off three or four times during start-up, until I realised what the problem was.

How can I get my computer to recognize that it has a CD drive as well as the DVD drive? Thanks 92.29.117.124 (talk) 00:57, 20 February 2011 (UTC)

When you restart your computer, open the BIOS to see it recognizes the drive. If it does, it's most likely a software problem. If it doesn't, it's almost certainly a hardware problem.

If it doesn't recognize the drive, you probably have the master/slave settings set incorrectly on the drives. Depending on the vendor, year of creation, etc. there are different ways to set a drive as master/slave - usually they are written right on the CD drive documentation, but you may need to look online. On my old CD drives, there were little pins in the back next to the power socket and the I/O cord. Magog the Ogre (talk) 01:17, 20 February 2011 (UTC)

Even though you didn't touch the CD drive, you could have easily disturbed the cabeling to it. Check the flat IDE cable is definitely seated correctly both at the CD drive end of things and the other end where it connects to the motherboard. The power cable is unlikely to be unseated because you say the draw still opens when you press eject, and because in my experience the power cable is usually a very tight fit. Astronaut (talk) 14:40, 20 February 2011 (UTC)

Verifying that copied files are identical with their source

I have copied many binary files from a pendrive to my harddisk. Two or three of them were said to be uncopyable due to being corrupted. What's the easiest way of checking that the remainder are exactly identical to the original files? I'm using WinXP SP3. Thanks 92.29.117.124 (talk) 01:09, 20 February 2011 (UTC)

You'll want to run a checksum on the drive data. There are several methods (and programs) listed in the linked article. Magog the Ogre (talk) 01:25, 20 February 2011 (UTC)

From a command prompt, use fc to compare the files. fc/? will show the syntax. You'll need to use the /b switch. If you're not comfortable with the command line interface, there are many graphic/windows-based file comparison programs available, at least some of which will be freely available. Mitch Ames (talk) 02:37, 20 February 2011 (UTC)

Using something like MD5 or SHA-1 would be the most reliable. Microsoft has a free program called File Checksum Integrity Verifier. Here's a link [6]. There are of course other programs that will do the same. Shadowjams (talk) 10:44, 20 February 2011 (UTC)

If you want to compare two files - eg after a file copy, when you have both instances - an actual file comparison program (fc or any other) is more reliable than a program that only compares a hash. A binary compare of the files is 100% reliable. A comparison of hashes is 99.many_nines%, but not 100%. Hashes do have their uses (eg checking for changes later when you don't want to keep a second copy), but they are not "most reliable" when you have two copies. Mitch Ames (talk) 11:57, 21 February 2011 (UTC)

Thanks. Is there any file manager that can compare/verify binary files? Thanks 92.15.31.249 (talk) 11:26, 20 February 2011 (UTC)

As Mitch Ames said, the windows shell does this out of the box. Just type

fc /b "path and name of first file" "path and name of second file"

If the files are identical, you'll get a message that the files are, indeed, identical. If they're different, you'll get a listing of the differences. --NorwegianBlue ^talk 22:28, 20 February 2011 (UTC)

I've been using the freeware Duplicate Cleaner to see if the files are identical duplicates - not quite what it was intended for, but it seems to be the easiest way to do it. 92.15.9.175 (talk) 15:07, 20 February 2011 (UTC)

Power issues, pt. 2

• Originally posted here: Wikipedia:Reference desk/Archives/Computing/2011 January 31#Power issues

About three weeks ago, I posted a question regarding some power problems I've had, and got good response, though not complete. We figured out that the plug on my power cord isn't making clean contact with the socket in my laptop (I've since been able to verify this, as putting the plug in my laptop always causes it to get really hot, when the power does make a connection).

My question continues: is it possible to replace a power socket in a laptop? I have a Dell Latitude d620, IIRC (all the stickers have fallen off the bottom, so I'm not sure). Magog the Ogre (talk) 01:12, 20 February 2011 (UTC)

The mains plug in the power supply (and inline socket in the cord) are normally standard IEC connectors, probably C5 clover leaf or C13 (standard computer). If you know how to use a soldering iron, then you may be able to open the power supply and resolder a new connector in. However, it is easier to buy a universal laptop power supply. Look at the existing power supply for the voltage and wattage; you'll need a replacement with the same voltage (1V out probably won't make much difference), and at least the same wattage (too little and you risk overheating the power supply; too much and you're just wasting your money). They come with several tips to suit most laptops; you may want to take your laptop to the shop to check, but I'd be surprised if it didn't have one to fit. CS Miller (talk) 08:18, 20 February 2011 (UTC)

CSMiller's answer concentrates on one side of the problem (replacing your power supply to get a plug that "fits better" into your laptop, which by the way can just as easily be done by only replacing the tip instead of the whole power supply) so let me tackle the other side: your laptop's socket. The problem could either be that the socket is worn and the plug is not making good contact, or the socket is fine but is coming loose from the motherboard itself. Either way a repair involves taking your laptop apart (which is a pain and a half as almost everything has to come out to remove a motherboard), then either re-soldering your socket to the motherboard or replacing it entirely with a new one. To answer your question: yes, it certainly is possible to replace the power socket. I don't know what the typical call-out fee and labour would be (if it's not under warranty or you don't want to do it yourself), but it will be much higher than the cost of the actual replacement part. Good luck! Zunaid 10:35, 20 February 2011 (UTC)

From memory, it is the mains inlet on the laptop's PSU is damaged, and it does not make a tight connection to the mains cord. The main connection then overheats, and damages the mains cord. However, the low-voltage connectors are fine. CS Miller (talk) 12:22, 20 February 2011 (UTC)

Well I know how to use a solder; I am a computer science major after all. But I don't actually have a solder, which is a problem obviously. It would be nice if I had a voltmeter to check where the connection dies; but I'm pretty sure it's right near where I plug in the cord, because a little jiggliing and it will work. Magog the Ogre (talk) 02:42, 21 February 2011 (UTC)

If the contact pin doesn't feel mechanically loose, use a bright light and a magnifier to inspect it for oxidation. If it's not nice and shiny, try cleaning it with De-oxit (wonderful stuff that you can get at Radio Shack or online). That fixes a lot of these problems. 71.141.88.54 (talk) 04:55, 21 February 2011 (UTC)

I had a similar problem, which turned out to be the connection to the motherboard. I was able to solder it back on, but unfortunately opening the laptop also severed the useless paper cable they use for the track ball. So now it has power, but I must use an external mouse. It was a royal pain, and I think I'd take it to a shop rather than try it again, myself. StuRat (talk) 06:17, 21 February 2011 (UTC)

I also have a hint for after you repair it. There's nothing to stop it from breaking off the motherboard again, so I'd plug/unplug it as few times as possible. For example, you could unplug the other end from the wall and wrap the cord around the laptop to transport it. This might damage the cord, but that's far easier to replace. StuRat (talk) 06:25, 21 February 2011 (UTC)

Apple's Darwin License

Is possible to get Apple's Darwin operating system under a permissive license? --Melab±1 ☎ 06:06, 20 February 2011 (UTC)

I suppose Darwin (operating system) comes under the license that it comes under. See its web site for details. What different do you need? E.g. the article on it mentions "with proprietary drivers" - if that is a problem, are you prepared to pay for the programming work needed to rewrite those? What do you consider permissive? 88.112.59.31 (talk) 19:17, 20 February 2011 (UTC)

It states on [7] that XNU is licensed under the BSD and APSL licenses. I prefer a license where I don't have to redistribute modifications under the same license (APSL). Do you think that Apple might make a move to releasing newer versions Darwin under a non-copyleft license? --Melab±1 ☎ 01:19, 21 February 2011 (UTC)

If XNU is dual licenced under the BSD and APSL licences then a non-copyleft licence is already available so I'm not sure what you're asking for. If you want other components, you should specify what although I somewhat doubt anyone here has any insider knowledge or Apple's future licencing plans and of course what we think is largely irrelevant here. Nil Einne (talk) 08:10, 21 February 2011 (UTC)

But I'm unsure about whether or not all files in its directory are dual-licensed or each component has a different license. --Melab±1 ☎ 22:15, 21 February 2011 (UTC)

Javascript and regex

I've currently got a piece of javascript code which outputs something similar to "2011-02-20T05:59:20Z". I am trying to pull the 05:59:20 out of this using a regular expression.

[0-9]{2}:[0-9]{2}:[0-9]{2}

This is the regex I've made, which works to pull it from that string. Unfortunately when I add that to this line of code using .exec(string), it makes it stop working.

original

result.innerHTML += '<li>(<a href="/w/index.php?diff=prev&oldid=' + edit.revid + '">diff</a>) <b>' + (edit.minor == undefined ? '' : 'm') + (edit.bot == undefined ? '' : 'b') + '</b> <a href="/wiki/' + escape(edit.title) + '">' + edit.title + '</a> ' + edit.timestamp + ' <a href="/wiki/User:' + escape(edit.user) + '">' + edit.user + '</a> (' + edit.parsedcomment + ')</li>';

Modified code

result.innerHTML += '<li>(<a href="/w/index.php?diff=prev&oldid=' + edit.revid + '">diff</a>) <b>' + (edit.minor == undefined ? '' : 'm') + (edit.bot == undefined ? '' : 'b') + '</b> <a href="/wiki/' + escape(edit.title) + '">' + edit.title + '</a> ' + [0-9]{2}:[0-9]{2}:[0-9]{2}.exec(edit.timestamp) + ' <a href="/wiki/User:' + escape(edit.user) + '">' + edit.user + '</a> (' + edit.parsedcomment + ')</li>'; 

What am I doing wrong here?

(and as a sidenote, how much of a nightmare would it be to subtract 05 from the first two digits (and add 24 if the result is negative) to adjust UTC to my timezone?) -- ʄɭoʏɗiaɲ ^τ _¢ 06:17, 20 February 2011 (UTC)

1. You have to surround regexps with slashes. 2. To subtract 5 from the timezone, use something like (parseInt(nn)+24-5)%24 where nn is the 2-digit string. The +24 makes sure the stuff in the parens is positive, and the %24 gets rid of the extra 24 if the result is too large. This is a standard and useful idiom for dealing with modulo calculations when you want to make sure the result is not negative. 71.141.88.54 (talk) 09:59, 20 February 2011 (UTC)

Alright, first step definitely worked... For the second, where would I put that in the code? I'd assume I can't do

+ (parseInt(/[0-9]{2}/.exec(edit.timestamp))+24-5)%24 + /:[0-9]{2}:[0-9]{2}/.exec(edit.timestamp) +

-- ʄɭoʏɗiaɲ ^τ _¢ 15:13, 20 February 2011 (UTC)

I think the first /[0-9]{2}/ in that example will match digits from the year, so you want something like /T([0-9]{2})/.exec()[1] to match the T05 and select the 05. The rest of it looks like it might work (since javascript automatically converts ints to strings when you try to add an int to a string). I'd say give it a try. Note that I haven't written any javascript in a long while, so my instincts about it aren't so good these days. Semi-related advice: Firebug is amazing and is near-indispensible for debugging complicated javascript, so you might want to start using it if you're not already. Also: irc freenode #javascript is probably a quicker place to get this type of help. 71.141.88.54 (talk) 02:25, 21 February 2011 (UTC)

Awesome, I'll definitely check that out next time I have problems. Your solution resulted in NaN:59:20, but it set me in the right direction. What I ended up doing was pulling the UTC time out of the original string, then when I added to result.innerHTML, I pulled the first two numbers, did the math, and displayed the remaining numbers.

        edit.timestamp = /[0-9]{2}:[0-9]{2}:[0-9]{2}/.exec(edit.timestamp);

        result.innerHTML += '<tr><td><b>¤</b></td><td width="25%">(<a href="/w/index.php?diff=prev&oldid=' + edit.revid + '">diff</a>...<a href="/w/index.php?title=' + edit.title + '&action=history">hist</a>) <b>' + (edit.minor == undefined ? '' : 'm') + (edit.bot == undefined ? '' : 'b') + '</b> <a href="/wiki/' + escape(edit.title) + '">' + edit.title + '</a></td><td>' +  (parseInt(/[0-9]{2}/.exec(edit.timestamp))+24-5)%24 + /:[0-9]{2}:[0-9]{2}/.exec(edit.timestamp)  + '</td><td><a href="/wiki/User:' + escape(edit.user) + '">' + edit.user + '</a> (' + edit.parsedcomment + ')</td></tr>';

And it works! Thank you :) - ʄɭoʏɗiaɲ ^τ _¢ 03:50, 21 February 2011 (UTC)

Cool! It's worth figuring out how to use groups in regexps (that's using parens in the expression to pull out pieces of the match), and also as a matter of style I'd probably say edit.timestamp.substring(0,2) to get the first 2 chars once you've already got the timestamp, rather than doing a second regexp match, but either way works. 71.141.88.54 (talk) 04:18, 21 February 2011 (UTC)

Note, there is another issue, which is if the timezone correction does go over the 24-hr boundary, then adjusting it means you also have to adjust the date. There are probably some built-in functions that can help with this but I don't remember them well enough. Check a reference guide. 71.141.88.54 (talk) 04:24, 21 February 2011 (UTC)

This code has been my intro to both javascript and regex, so I'm learning as I go quite honestly. I only needed the time and not the date; I'm using this to make a mini-watchlist call that shows the title, time, user and comment. Thank you for all the help. - ʄɭoʏɗiaɲ ^τ _¢ 04:45, 21 February 2011 (UTC)

It occurs to me that there's another problem with that code, which is that the timestamp after you do the arithmetic could come out as "3:45" instead of "03:45". If it's just for your own use, you might not care, but if you're planning to release the code to other people, it's best to make it as free as possible of subtle little gotchas like that. There are some sprintf-like functions you can search for and download, so you can do "%02d", or you could just code a little adjustment for the n<10 case. Javascript is quite powerful but it can be a bit "loose" (it's easy to make unnoticed errors) and difficult to debug in a browser environment, so be persistent ;-). 71.141.88.54 (talk) 20:02, 21 February 2011 (UTC)

Asus and Toshiba

Which brand is the more reliable of the two? 24.189.87.160 (talk) 10:15, 20 February 2011 (UTC)

Personally, I prefer Asus. Although Toshiba is a more established company. Asus makes some high end gaming computers and because it's not technically a name-brand, they sell pretty cheap compared to their peers.--v/r - TP 18:57, 20 February 2011 (UTC)

In my limited experience with laptops I found Toshibas to be better built and overall more thought-through than Asus laptops. This, however, comes from a person who does not like laptops. --Ouro (blah blah) 08:51, 21 February 2011 (UTC)

Asus are considered to be robust. Toshiba look better, and are more expensive. You can buy any one with peace of mind. The cheapest Asus is cheaper than the cheapest Toshiba. —Preceding unsigned comment added by 212.169.187.5 (talk) 13:52, 21 February 2011 (UTC)

international email

How do I send an email to another country. Do i need to do something extra? Thanks Tom —Preceding unsigned comment added by 99.66.171.155 (talk) 11:58, 20 February 2011 (UTC)

As a general rule, all you need is their email address and the Internet will do the rest. --Phil Holmes (talk) 12:09, 20 February 2011 (UTC)

In fact, there's no general way to tell what country the person you're emailing is located in. None of the Internet protocols are designed to be aware of national borders. Paul (Stansifer) 13:04, 20 February 2011 (UTC)

You might want to be aware of security monitoring and censorship. In the US, emails crossing the borders with certain "terrorist keywords" will get extra attention, while some nations might block emails on topics they object to, like any mention of democracy. StuRat (talk) 06:09, 21 February 2011 (UTC)

haha, no, just make sure you get the address exactly right - pay especial attention to the end, maybe sojeone is using a different extention, not .com like you're used to... —Preceding unsigned comment added by 109.128.213.73 (talk) 15:14, 21 February 2011 (UTC)

Two things I should mention here: 1) ".com" does not imply any country, and even for top-level domains that do imply countries, there's not necessarily any direct connection. (I live in the US, but I lived in the UK when I got my domain, so my email address still ends in ".uk".) 2) When you dial an international phone number, you have to add the country code onto the start. I have met people who believed there was some equivalent in email (so if your email address was foo@example.com and you lived in the US, then I would have to email foo@example.com.us if emailing you from abroad). This is not so, at least not nowadays. The same email addresses are used everywhere. Marnanel (talk) 15:34, 21 February 2011 (UTC)

compress

I have lets say 100,000,000 one million small files mostly html, totaling no more than 500MB in all. I want to compress them with 7zip, but due to the limitations discussed at 7zip#Limitations it is not possible to create an archive with so many small files on my limited ram computer. What alternative methods could I use to overcome this? I was thinking about putting the files into several .tar archives, and then running 7zip on the .tars. However, I've never used .tar so I don't know if this is a good idea. Will 7zip compress the files as effectively if they are in .tar archives? Or would it be pointless like trying to compress .zip files? 82.43.92.41 (talk) 14:00, 20 February 2011 (UTC)

Why not just put them into several 7zip files, and add those to the archive. Although 7zip (probably) won't be able to compress them further (though who knows, maybe its header information compresses quite easily, so it could compress the total individual archive sizes further) , it should include them without a complaint. If it doesn't include them without a complaint, just rename the files from .7zip to .xyz. I doubt 7zip will say "I see what you did there! You're trying to get me to think that this is just some random format I don't know about, that happens not to compress very well. But I looked at these files - they're 7zip files, just with a different extension! You think you can get around my arbitrary limits? Well, you got another think coming, bud. I am NOT including these files. Go use winzip or something, maybe they'll let you commit these acts against nature." 109.128.201.187 (talk) 17:07, 20 February 2011 (UTC)

Because of the 7zip limitations discussed in the article I linked to. Using several 7zip files, I'd have to divide into 1,000 separate 7zip archives which is not feasible. 82.43.92.41 (talk) 18:47, 20 February 2011 (UTC)

If only there were such a thing as a "scripting" language, where you could write a small program to give 7zip "commands" - then doing it into 1,000 or a million times would be easy. But that's crazy Unix talk. 109.128.201.187 (talk) 19:26, 20 February 2011 (UTC)

If you can write a .bat script which would compress 100,000 files at a time with 7zip, then compress the next 100,000 files etc until the whole folder is processed, I'd be very grateful 82.43.92.41 (talk) 19:34, 20 February 2011 (UTC)

Try it! The tar file should have many recurring byte sequences in it, giving recurring-sequence-based compression algorithms a "happy case" to work with. 88.112.59.31 (talk) 19:12, 20 February 2011 (UTC)

How can it be possible to have a hundred million small files which total no more than 500 megabytes? That would put the average file size at 5 bytes! I would hazard a guess that even the file's header would be more than 5 bytes in length. Did you actually mean totaling no more than 500GB, not MB? Rocketshiporion♫ 23:35, 20 February 2011 (UTC)

I made a huge mistake with the zeros, I meant "one million" files, not a hundred million. Sorry! 82.43.92.41 (talk) 23:47, 20 February 2011 (UTC)

Taring files before compressing them should work - in fact, it'll probably give you better compression than if you compressed them separately (assuming the files have similar type content). Most data compression schemes based off of Lempel-Ziv-type algorithms require sequential reading of the file during decoding - in order to get the random access in .zip files, each of the files are compressed separately, which means you don't get to take advantage of the redundancy between the different files. You can get around this somewhat by using solid compression (which is not supported by the .zip archive type, but is supported by the .7z type), although many implementations of this are effectively tar->compress. By the way, compressing already compressed files, as suggested above, is probably the worst way of handling it - you don't get to take advantage of the redundancy between files, and you bloat the archive with the compressed files' header information. -- 174.21.250.120 (talk) 07:38, 21 February 2011 (UTC)

Adobe Flash Player

Is there a safe alternative place to download the latest version of Flash Player for Firefox on Windows? I've been trying to download it from the official website (http://get.adobe.com/flashplayer/completion/?installer=Flash_Player_10.2_for_Windows_-_Other_Browsers) for ages, and it downloads reeeeeeally slowly. This is free software: I'm not trying to pirate anything. I'd just like to be able to finish downloading it before bed! 86.161.110.118 (talk) 17:55, 20 February 2011 (UTC)

Oh, I should have said, Adobe Reader downloaded very quickly, so I know there's no problem with my download speed in general. 86.161.110.118 (talk) 17:56, 20 February 2011 (UTC)

http://www.wikifortio.com/735750/install_flash_player.exe 82.43.92.41 (talk) 18:20, 20 February 2011 (UTC)

Oh wow, that was really quick! Thank you so much. 86.161.110.118 (talk) 18:44, 20 February 2011 (UTC)

GIMP plugin to read Canon EOS raw files?

I installed the GIMP on my mother's Windows computer, and she would like to use it to read raw image files from her Canon EOS 5D Mark II DSLR camera. Is there a GIMP plugin for Windows available for that? JIP | Talk 20:27, 20 February 2011 (UTC)

UFRaw is compatible with GIMP. It has apps that read Canon Raw and I recommend reading though the site so that you can pick out what you (or Mom) needs.--Aspro (talk) 20:54, 20 February 2011 (UTC)

February 21

becoming a Unix hacker: Vi

I'm trying to become a Unix hacker, so I'm learning Vi as part of it. I have a few questions:

• Why are the cursor keys backward for me: The "cursor" keys hjkl, go: left, DOWN, UP, right, instead of how it should go (left UP, DOWN, right). It gets me every time. Obviously up is like left, and not down is. What is the logic to it, and can I change it to be normal? Also the real cursor keys just insert gobledegook like D and stuff.
• Why isn't there any indication whatsoever of whether I'm in insert or edit mode? I understand that Vi was made in the days when updating a single character on the terminal screen you were using at home meant the computer would dial 0, you would have to ask to ask the operator to patch you through to the University, you would have to ask the University operator to patch you through to the computer department, and then you would ask a typist to update your screen or something. So, that's why there are all these buffer tricks and hardly any updating. But, when it's all local on my own machine, shouldnt I have some means of knowing which mode I'm in?
• Do real Vi users get confused, or does it become real easy to keep track of which mode you're in after a while? Every time I switch back to Vi from another application, I press escape three or four times, then "i", before I start typing. I can't just press "i", you see, because sometimes that would just type an 'i', which I would have to switch back to edit mode to fix, but it takes a long time, because I would end up moving down or up instead of left to fix it, etc. How are you supposed to remember whether you left your vi in edit or insert mode half an hour ago?
• In NEITHER edit NOR insert mode will it let me add to the right-hand part of a line. So, if a line reads "i++" and I want to add the missing semicolon, I can't get any farther right than the +. I have two choices. I can insert here: i+;+ then go i+;x+ as I try to use x to delete it, forgeting I'm in insert mode, then I'm in edit move but have moved four or five lines away by hitting the wrong "cursor" key, so I make my way back meticulously and use "x" to get rid of the "x", and the "+". Now I have "i+;" and there's just one more step: putting in the missing +. So, I go off in the wrong direction with the cursor keys again, then finally make it back, press escape a few times, press i, and then insert the missing "+". Overall, every time I have to add to the end of a line, it takes me about 30 seconds.
• When I switch from insert to edit mode, it's a gamble what pressing "x" will delete. How do I figure it out?

Those are the major questions I have, for the rest I'm being a good boy and trying to refer to documentation. So far, I have spent about an hour and a half fighting vi - and all I'm doing is copying, by hand, a code sample from a web site (obviously, given my experience with the cursor keys, I'm not about to try to find out what ctrl-v would do). I can't imagine how things will get when I have to do my own editing. 109.128.201.187 (talk) 00:27, 21 February 2011 (UTC)

I also, this was rather foolhardy, but I tried pressing the "insert" key on my keyboard to see if it would toggle between insert and overtype mode. I did not realize that vi interpreted this as meaning it had to toggle the middle of a variable from a lowercase to a capital letter, thankfully it only cost me ten minutes to figure it out. The only times I've ever had a user experience like this was when the memory of an application I was using on Windows got really badly corrupted. Right before it crashed, it would give me this same type of user experience, down to inserting weird characters for no reason and jumping around the screen and doing other weird stuff as I typed (obviously, in vi, because I was in the wrong mode). 109.128.201.187 (talk) 00:38, 21 February 2011 (UTC)

See Arrow keys#HJKL keys. To add to the end of a line, hit A (for "append") and it'll jump to the end of the line and go into edit mode there. -- Finlay McWalter ☻ Talk 00:41, 21 February 2011 (UTC)

Or for the append, do 99la (that's lowercase L). That means "move 99 chars to the right then append here"; 99l will move you to the end of a line (that's got fewer than 99 chars; for really long lines 999 etc.) Note that if your terminal is set up properly, the keyboard's normal arrow keys should work fine (as a modern VI is fully termio aware). -- Finlay McWalter ☻ Talk 00:46, 21 February 2011 (UTC)

Actually my bad - arrow keys in edit mode do insert wonky chars. -- Finlay McWalter ☻ Talk 00:55, 21 February 2011 (UTC)

Let me ask you guys, honestly. Are you Unix hackers? And still, after all these years of using vi every day, this confused? As for "if your terminal is set up correctly" or if it's a "modern" vi. I guess no to both - I mean, it's only the default full desktop install of Debian 6.0, which I downloaded, assured it would be the latest and greatest, direct from Debian's site a few days ago - I didn't change a thing. I know they're 31337 Unix hackers too, because "vim" isn't installed, only vi is. But who would want to move around in edit mode anyway? You're in an editor to type, not to dick around. Typing "991A" is a helluvalot faster than what I've been doing in vi. I guess I'll have to have a very long beard before I learn why pressing the right - not arrow key, but right "cursor key" (from hjkl) at the end of the line doesn't have that behavior. I mean, what kind of a twisted mind would it take to think "if someone is going to want to insert something in a line, obviously it will be before the last character. Why would anyone insert anything after the last character in a line? How could the last character POSSIBLY not already be the one that belongs at the end?" I tell you guys, I am in wonderland, and vi is the hatter. 109.128.201.187 (talk) 01:02, 21 February 2011 (UTC)

vi is still proprietary. On most UNIX-like systems, vi is aliased to some variant of vim, which is open source. Yes, in insert mode you can't do much except insert, and yes, characters that aren't in 7-bit ASCII give undefined results. If you're confused about which mode you're in (most vims will tell you on a status line), just hit ESC. If you're in insert mode, this will take you to command mode; if you're in command mode it won't do anything. I'm sure a little Googling will find you a command list (pretty much every key does something in command mode) that will save you time over random bashing. PhGustaf (talk) 01:17, 21 February 2011 (UTC)

Your "vi" is probably really ViM, which is plenty modern. I use vi only if I'm doing small edits in a restricted environment (that's pretty much as root editing config files). For almost everything else I use emacs. In times of yore I wrote pretty large projects entirely in vi (real, Bill Joy vi), and you get used to it (but I was no expert); there's plenty worse than vi (e.g. VMS ed, DOS edlin, HP's PAWS-ed). I'd personally recommend emacs in X windows. -- Finlay McWalter ☻ Talk 01:19, 21 February 2011 (UTC)

That's an intriguing possibility. But I tried typing "vim" and it didn't open vim, so that would be rather bizarre. Still, whereis vim shows it's SOMEWHERE. How could I tell if I'm typing in vim or vi? Perhaps it will help if I assure you that there is absolutely no status line that tells me what mode I'm in. 109.128.201.187 (talk) 01:49, 21 February 2011 (UTC)

For HJKL: This confused me too when I was first learning vi, until I saw that the letter J, if you squint, looks a little bit like a down arrow. That helped me to remember that J means down and K means up. After a while it became second nature, and now I don't have to think about it. For insert mode: If you're not sure whether you're in insert mode or not, press Esc a few times, and then you'll know you're not in insert mode. But this is something else I learned to keep track of subconsciously, so I don't get confused about it very much any more. —Bkell (talk) 01:14, 21 February 2011 (UTC)

About your comment about inserting after the last character in the line: There are (at least) two different ways to enter insert mode. The first is "i", for "insert," which means "enter insert mode and start inserting before the current character," and the second is "a", for "append," which means "enter insert mode and start inserting after the current character." So, if you are trying to insert after the last character in the line, you want to position the cursor over that character and press "a" to enter insert mode, not "i". These commands also have capital-letter equivalents: capital "I" means "enter insert mode and start inserting at the beginning of the current line," and capital "A" means "enter insert mode and start inserting at the end of the current line." So usually if you want to add something to the end of a line the easiest thing to do is just to type "A" rather than laboriously moving the cursor all the way to the end of the line first. —Bkell (talk) 01:22, 21 February 2011 (UTC)

For your specific problems, I would first look at your terminal configuration. All the times I've used vi/vim recently, there has been a clear indication of "-INSERT-" on the last line of the screen and the keyboard's proper arrow keys have worked as one would expect in both command and insert mode. You setup is obviously wrong somewhere unless you are using a very, very old old system or a very, very old console terminal program.

Like Finlay, I only use vi for tiny jobs or when I have to - vi's one advantage is you can pretty much guarantee it is installed on any *nix system. In my opinion, vi's major shortcoming is its command interface - honestly, who the hell thought HJKL are good cursor keys when all keyboards since at least the early 80s have had perfectly good dedicated arrow keys. I suggest you instead learn the basics of vi for the rare occasion when you need to use it, and use a proper editor for everything else. Incidentally, if you think knowing vi will make you a hacker, then you have a lot to learn. Astronaut (talk) 05:17, 21 February 2011 (UTC)

"if you think knowing vi will make you a [1337 Unix] hacker, then you have a lot to learn" - on that point, my friend, you are very mistaken. 109.128.201.187 (talk) 12:21, 21 February 2011 (UTC)

I'm an emacs user, but I think that hjkl is fine; I picked it up from playing Roguelikes, and I think that it makes more sense than using emacs's (Ctrl+) bnpf, which are at random locations on the keyboard. In general, I like emacs better, though. Paul (Stansifer) 17:06, 21 February 2011 (UTC)

A few notes: first, Debian has many versions of vi available; the only one not classified as "optional" is vim-tiny, which as its name suggests is missing a lot of the advanced features. When multiple vi packages are installed, the one that is linked to by the plain command "vi" (/usr/bin/vi) is chosen by the alternatives system (there's a command update-alternatives --config vi). Try a :version command to see which vi you're currently in. Second, showing the current mode in the status line is activated by the "showmode" option (:set showmode) and has been in vim, nvi, and the proprietary/SysV/"real" vi for a long time. Third, the menomnic I was given for hjkl is that the lowercase j and k have a descender and ascender respectively. Fourth, the insert key is an unreliable key because it sends an escape sequence that depends on the terminal type. It wouldn't hurt to send a bug report for whichever terminal you were using; making the terminal emulators and the editors and the terminal database agree with each other is the sort of thing Debian package maintainers are supposed to do and they've obviously messed this one up. But when you're good with vi you'll never use those keys. Reaching all the way over there is a waste of time when all the same functionality is right under your fingers already. Finally, vi is the proper editor. ed is the one you learn for emergencies.

Oh... and x in command mode deletes the character under the cursor. X deletes leftward. That should be easy enough. 67.162.90.113 (talk) 06:30, 21 February 2011 (UTC)

YouTube doesn't work in Safari

I'm using Safari 5.0.3 on OS X 10.6, and for the past week or so, YouTube videos have just been appearing as an empty black box. They play fine when they're embedded on other sites, but they're unwatchable at youtube.com. Clearing cookies has not fixed it. Any ideas? --140.232.176.191 (talk) 07:10, 21 February 2011 (UTC)

There are discusions about the problem here.Forum -Safari for Mac --Aspro (talk) 12:23, 21 February 2011 (UTC)

iPhone un-shuffles

I'm not sure if this problem is specific to the iPhone 4 or happens on other iOS devices. Whenever I'm listening to my music in a certain playlist, I hit "Shuffle" at the top of the song list and continue on with my day. Occasionally, however, the music becomes "unshuffled." I'll start to hear several songs from the same artist or same location in the playlist (for example, after 15 songs have played), and when I check, it's playing song "256 of 700" instead of "16 of 700," and the shuffle icon is grayed out. I can't pin down if any actions I take trigger it. I've seen no mention of this anywhere else. Anybody know what's going on?--The Ninth Bright Shiner 15:09, 21 February 2011 (UTC)

Help me with Craigslist, please. Also, what great alternatives are there that are like CL?

This is my job ad posted to their site: http://ksu.craigslist.org/edu/2218478487.html

However, it doesn't show up on the list it's supposed to be on: http://ksu.craigslist.org/search/edu?query=+

It's still green, so still active. Why won't it show up on the list if active?

Moreover, does Craigslist have a realtime chatroom anywhere? Forums are inherently slower in responses.

Besides, since the Craigslisting isn't turning up any results, what are some great Craigslist alternatives to post free job listings at, that anyone within the Manhattan, KS area will still see? --129.130.98.164 (talk) 18:55, 21 February 2011 (UTC)

Have you tried non-online options? My suggestion would be to put up some fliers in places where people who have taken that class (e.g. majors in the same department, or graduate students) will find it. You can be much more specific in targeting your audience than Craigslist in this case, since you can reasonably guess where said people might be found. --Mr.98 (talk) 19:13, 21 February 2011 (UTC)

(ec) I know that the CL search engine takes a little while to update. CL doesn't have online chat, but its forums move pretty fast. You should probaly also look for job or tutoring boards within KSU itself, including physical noticeboards (the kind where you write your ad on a slip of paper and attach it to the board) within the communications department. You could also ask the department secretary or one of your instructors if they can refer you to any tutors. I'm really surprised you're having trouble getting help, since at any university there are always LOTS of students trying to pick up a bit of $$$ by tutoring. You might also drop the requirement that the tutor have actually taken that particular class. At least at my school, tutors were often graduate students who had the relevant knowledge to help with the class, but had done their own undergraduate classwork elsewhere. 71.141.88.54 (talk) 19:17, 21 February 2011 (UTC)

Did you respond to the e-mail that the Craigslist robot sent you? Maybe that's why it doesn't show up in searches? Since this is now 5 days old, I'd start again from scratch, by the way. I agree that physical postings around the school are a good idea. Comet Tuttle (talk) 19:19, 21 February 2011 (UTC)

Will a USB harddrive meant for Windows also work for Ubuntu?

The (500GB) harddrive has a USB 3.0 connection and NTFS file system. The sticker on the packaging says it is for Windows and does not mention Ubuntu at all. Will it work on Ubuntu too? —Preceding unsigned comment added by 20:01, 21 February 2011 (UTC)

I would be very surprised if it didn't. USB is a standard interface that's supposed to work everywhere: that's what the U means. Marnanel (talk) 20:08, 21 February 2011 (UTC)

Linux has had USB 3.0 support since kernel 2.6.31 (September 2009); Ubuntu currently provides 2.6.35. Officially Windows 7 won't have its own support until SP1, although you can use the vendor-supplied drivers (for a USB3.0 motherboard or adapter card). Note that if you don't have a USB3.0 motherboard or adapter card, it will fallback to USB2. The last few Ubuntu releases will read and write NTFS partitions. -- Finlay McWalter ☻ Talk 20:15, 21 February 2011 (UTC)

The hard drive itself will almost certainly work with Ubuntu, or any other modern Linux distribution, even if it doesn't say it will. The file systems on the hard drive are another matter entirely. There are some file systems that are compatible with both, such as FAT16 and FAT32, but these won't take full advantage of either Windows or Linux. Windows these days uses NTFS, while Linux uses ext3 or ext4. I am not sure about their compatibility with different operating systems. When I buy a new hard drive to use on my Fedora Linux system, the first thing I do is reformat it as ext3 or ext4. JIP | Talk 20:41, 21 February 2011 (UTC)

Linux supports all major Windows-style file systems, including FAT16, FAT32, and NTFS. Support was provided in Kernel 2.6.0 using the NTFS-3G driver and FUSE. I regularly read and write to local and networked NTFS drives and partitions in the latest Ubuntu, without issue. Nimur (talk) 21:01, 21 February 2011 (UTC)

What font is this?

On my homepage http://www.stucktothefridge.co.uk/ I have no idea what the name of the font is which says "contemporary photography...."

Can anyone tell me or give me a few approximations so I can find something similar?

Lucas 83 21:24, 21 February 2011 (UTC) — Preceding unsigned comment added by Lukerees83 (talk • contribs)

user agents

Why do almost all user agents have "Mozilla" in them? Even Internet Explorer — Preceding unsigned comment added by K4t84g (talk • contribs) 21:38, 21 February 2011 (UTC)

"Mozilla" was the user agent string used by Netscape Navigator. As Jamie Zawinski explains here (in "cloakers") IE pretended to be NN so it was served the same content. So now everyone does it. -- Finlay McWalter ☻ Talk 21:58, 21 February 2011 (UTC)

An accident of birth. 109.128.213.73 (talk) 23:42, 21 February 2011 (UTC)