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November 20

Multi-core processor

This article talks about performance of multiple cores versus one, but seems entirely focused on how to get the optimal performance out of a single program, assuming nothing else is running. What I'm more interested in is the real world, where each PC has dozens of processes either running or idle at any given time. How does having multiple cores impact that situation ? Specifically, can you put the program you care most about, let's say a streaming video you are watching, on one core, and keep everything else off of that core, so that that program will not lag whenever a virus scan runs or a piece of software decides to look for an update ? StuRat (talk) 02:11, 20 November 2012 (UTC)

Yes, see processor affinity for starters. ¦ Reisio (talk) 02:16, 20 November 2012 (UTC)

Although affinity may not be sufficient to esnure a virus scanner will not lag your video - processes not only compete for CPU, but also for memory, disk and perhaps the network. Good video players that want to avoid interrupted playback, should also take care to Data buffer enough data so that it still has something to play if the virusscanner outcompeted it for hard disk access, and lock its memory pages so that it doesn't get swapped out entirely by that memory-hungry scanner. Unilynx (talk) 20:43, 20 November 2012 (UTC)

You might also look at scheduling (computing)#Operating system scheduler implementations, which is different from what you suggested, but also deals with prioritizing the use of CPU resources for specific programs. Dragons flight (talk) 13:03, 20 November 2012 (UTC)

Quickly open list of links as tabs in Firefox

Hello! I'm currently in a situation where I have very intermittent access to the Internet via Wifi (Internet access for about 5 minutes at a time), so what I've been doing is saving a copy of the HTML of the websites I like to visit, and then read them offline at my leisure. These HTML pages contain links to images and other content I'd like to view, so I save those links, one per line, in a text file to copy and paste into Firefox next time I'm in Internet range. Obviously, following a long list of links can be a slow and tedious task, so I wondering if there is a more efficient and quick way of opening a file of links into tabs with Firefox. I would expect that this could be accomplished with Greasemonkey, but I have no experience using that plugin, so I would need a beginner's explanation for that. Thank you for your time and help.--el Aprel (^facta-_facienda) 07:16, 20 November 2012 (UTC)

No doubt a number of extensions for this purpose. ¦ Reisio (talk) 08:12, 20 November 2012 (UTC)

I don't have firefox installed to test it right now, but try right-clicking on a folder in your bookmarks - I think there is an option to open the contents in new tabs. 209.131.76.183 (talk) 12:33, 20 November 2012 (UTC)

You can use the built-in functionality (rightclick on a tab, select bookmark all tabs, give the folder with all the bookmarks a name. Then go to your bookmarks, browse to the folder you just created, right click it and chose open all in new tabs) or you can try CopyAllURLs. Install, restart Firefox. You can find it at the bottom of the Edit-menu. If the menubar is hidden press the left Alt key. Trio The Punch (talk) 12:52, 20 November 2012 (UTC)

Here is a "semi-automatic" option using Wikipedia's external link feature:

1. Edit any page, for example by entering "wp:sb" in Wikipedia's search box and clicking the "Edit" tab. Or store http://en.wikipedia.org/w/index.php?title=Wikipedia:Sandbox&action=edit in your browser bookmarks and select that.

2. Clear the edit box (for example with Ctrl+A and Del) and copy-paste the url's. They can be formatted with one per line if you start the line with a colon.

3. Click "Show preview" (not "Save page"), hold down Ctrl and click on each url.

PrimeHunter (talk) 14:31, 20 November 2012 (UTC)

Snap Links Plus is your friend, it opens multiple links contained in a selected area in new tabs. Trio The Punch (talk) 14:53, 20 November 2012 (UTC)

Continuing from the first part of #3 of PrimeHunter's response above, if you want to open said links even quicker: Click and hold once on the first link, "drag the link off the link" (yeah, that's the only way I can describe it -- so it doesn't actually navigate to the link), then hold Ctrl and press ↵ Enter, press Tab ↹ to move to the next link, then do Ctrl+↵ Enter again, and so on. -- 143.85.199.242 (talk) 16:23, 20 November 2012 (UTC)

https://addons.mozilla.org/en-us/firefox/addon/selection-links/ AvrillirvA (talk) 16:28, 20 November 2012 (UTC)

This plugin is simply wonderful for this task. Many thanks.--el Aprel (^facta-_facienda) 04:26, 21 November 2012 (UTC)

Resolved

Clipboard

Is it possible to write some javascript to place some javascript derived text into the windows clipboard? -- SGBailey (talk) 09:01, 20 November 2012 (UTC)

In some cases. Some info. Its easy if you want it to work on just one computer with one browser. Trio The Punch (talk) 13:04, 20 November 2012 (UTC)

Thanks — Preceding unsigned comment added by SGBailey (talk • contribs)

set top box

when i attached my analog cable line to tuner(model: zeb-c2010) there was no disterbence but through a set top box then the picture of monitor disappear for a second and then appear again disappear and repeated it. this is the same when I attached my sony cyber shot camera and play a video taking by this camera . can you fix my problem please. Rikisupriyo (talk) 09:52, 20 November 2012 (UTC)

What inputs are you using to the monitor, in each case ? If you have alternate inputs you can use, in each case, try those. So, if you are using an HDMI input, try either another HDMI port, if there is another on the monitor, or try a different input method completely, like DVI.

There might also be settings for the monitor which need to be changed to accept different inputs. What model monitor is it ? StuRat (talk) 05:44, 21 November 2012 (UTC)

Multiple threads

Is there an order where threads receive the output or is it totally random? Can I make a random generator out of it?

There are two threads, one writes '.' and other writes 'M', both are for loops. Executing the program multiple times, gets this:

Extended content

MMM.MM.M.M.M.MMMMMMMM.M.MM.M.M.M.MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM......................................................................................... MMMMMMMMM.M.M.MMMM.M.M.M.MMMM.M.M.M.M..M.M.M.M.M.M.M.M..M.M.M.M.M..M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M............ MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM.................................................................................................... ...M.M.M.MMMMMMMMMMMMMMMMMMMM.M.M.......M.M.MMMMMMMMMMMM.M.M.M.MM.M.MMMMMMMM.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.M.MMMMMMMMMMMM..........................................M......M..MMMMMMMMMMMMM......

So how does it work? 190.60.93.218 (talk) 16:30, 20 November 2012 (UTC)

Thread scheduling depends on the load imposed on the CPU by other tasks, the state of the CPU and RAM caches, on the occurrence of real-world events like timers and hardware interrupts, and on the (often quite sophisticated) cpu and io scheduling algorithms. So there's a fair amount of real-world randomness, and it's a complicated system to begin with. So, as a reasonably approximation, you can consider thread scheduling to have a random component. You can't safely rely on the OS scheduling one thread after another - the best you can do is hint to the scheduler with thread, thread-group, process, and process-group parameters like priority and affinity. There are much much better ways to efficiently collect the entropy available to a system - see Entropy (computing). -- Finlay McWalterჷTalk 16:41, 20 November 2012 (UTC)

Incidentally, stuff like this is especially prone to Heisenbugginess - simply by putting in those prints you've made additional system calls and generated additional IO, which will directly alter what's running and how threads get scheduled. Tracing systems like DTrace are less likely to cause this. -- Finlay McWalterჷTalk 18:11, 20 November 2012 (UTC)

Instead of having it write just M and ., make ten threads that do digits from 0 to 9. That should give you a better view of what kinds of patterns are discernible or not from the data. There are loads of tests one can run on such numbers to see if they conform to technical definitions of randomness. --Mr.98 (talk) 19:02, 20 November 2012 (UTC)

But you could only be sure that the pattern holds on that system, as currently configured, and under a similar load as when the test was run. Different programs running, new updates, driver changes, a screensaver triggering, dynamic CPU reclocking for power saving, network traffic (that could be triggered entirely externally), free memory, playing media and tons of other things can all have subtle effects on how threads are scheduled. 209.131.76.183 (talk) 13:32, 21 November 2012 (UTC)

Can I Still Update Win95?

I am about to load Win95 onto a PC so that I can use it to play some old favourite games. My guess is that the installation CD that I have sent for will be the raw Win95 and will not have any of the subsequent updates. My question is, if I connect to the Windows Update website with a machine running Win95, will the update site still update that old OS? Or have they stripped all that historic stuff off their site by now? Gurumaister (talk) 19:55, 20 November 2012 (UTC)

I doubt it.. I haven't got Win95 around, but I dug up an old copy of Windows 98 Second Edition, and it was unable to access windows update - it got stuck in a redirect loop, and trying to update the browser failed too (Microsoft tried to provide IE8 for WinXP, whose installer doesn't even launch, as it expects NT-specific APIs). So if Win98SE fails, it's unlikely that Win95 would work. However, the service packs that Windows update provided have always been available for download too, so the updates will still be out there on the internet... somewhere. Microsoft's links to it are dead, but they still have some Windows 95 stuff floating around on their FTP server - this seems to be service pack 1 for Windows: ftp://ftp.microsoft.com/softlib/MSLFILES/setup.exe Unilynx (talk) 20:33, 20 November 2012 (UTC)

Are you sure your old favorite games don't work on your ordinary Windows install with the compatibility set to Windows 95? ¦ Reisio (talk) 21:18, 20 November 2012 (UTC)

I would recommend installing Win95 in a virtual computer. You can use Virtual PC 2007, download it here. I found some pretty detailed tutorials. The "Virtual Machine Additions" support Win95, install them next. The latest version of Win95 is the OEM Service Release 2.5 (from here, more info here). The Microsoft Plus! 95 Pack for Windows 95 is very useful. You won't need Windows Update. Trio The Punch (talk) 21:32, 20 November 2012 (UTC) p.s. If (some of) the games you want to play have a DOS version as well you can use DOSBox.

(ec)Microsoft ended all support for Windows 95 a decade ago (this ref says 2002, this one 2001). -- Finlay McWalterჷTalk 23:02, 20 November 2012 (UTC)

Yes, and you probably can run all these games in any one of their newer OSes just fine, or you can run a VM... however, that they ended support doesn't necessarily mean you can't upgrade the OS to whatever the last version they put out was. Shadowjams (talk) 23:04, 20 November 2012 (UTC)

Thanks Guys. The VM option doesn't work well as I can only get a rather small VM window within which my Win95 sits. It isn't a realistic environment in which to run software. I'm not sure how to use the 'compatibility mode' suggested by Reiso - any hints will be much appreciated. Gurumaister (talk) 07:22, 21 November 2012 (UTC)

Did you change the screen resolution? Did you try dragging the window to make it bigger? If you tried that and it didn't work, did you try temporarily decreasing the resolution of the host OS? http://support.microsoft.com/kb/292533/en-us?fr=1 Trio The Punch (talk) 11:42, 21 November 2012 (UTC)

Thanks Trio - the screen won't drag but changing resolution might do it. Gurumaister (talk) 11:47, 21 November 2012 (UTC)

You asked about Compatibility mode. Versions of Windows from Win2000 onwards allow you to fool programs into thinking you are running them on an older version. To activate it, right-click on the icon of the program in question and select Properties. Choose the Compatibility tab in the box that appears. You can then choose from the drop-down to select a version of Windows in which the program is known to work. There are also other options such as restricting the colour depth which you can try various combinations of to get the program running. Info from Microsoft on this feature is available here. - Cucumber Mike (talk) 14:53, 21 November 2012 (UTC)

Thanks Cucumber Mike. I will try that. Presumably that also means I will have to run the Game's installation program in compatibility mode. Gurumaister (talk) 16:17, 21 November 2012 (UTC)

Maybe, although in my experience the installers often work well - if a little clunky looking. I'd suggest trying it 'straight' first, then going through the compatibility options if you have trouble.

I'm back again. . . . I have tried using compatibility mode to install (Settlers II Gold Edition) but I get a message window telling me that it objects to being run on a 64 bit system. Ah well, maybe I need to continue with my plan to load an old PC with Win95. Thanks for all your help though. 82.71.20.194 (talk) 19:45, 21 November 2012 (UTC)

Oh, bummer. This article tells you about the reasons. Unfortunately there doesn't seem to be much you can do in Compatibility Mode. However, you may find these instructions helpful. They show how you can use Dosbox to run Settlers II. If you have other games from around the same era I can highly recommend Dosbox for getting them working. - Cucumber Mike (talk) 20:53, 21 November 2012 (UTC)

Compatibility mode won't work, but I think using a virtual computer will. There is a remake btw. Trio The Punch (talk) 20:55, 21 November 2012 (UTC)

maps of the world

There are zillions of maps of the world on the web. I'd like to see either something like what I describe below or something that can be used for the same purpose, especially if it's simpler.

Let (x₁, y₁), (x₂, y₂), (x₃, y₃), . . . . . ., (x_1 zillion, y_1 zillion) be a sequence of points along the coast of a continent so arranged that if you draw a line connecting the first to the second, then a line connecting the second to the third, and so on, until you get to the end then connect the last to the first, you get a reasonable map of the continent, and there's no pointless backtracking, and in each pair, the first coordinate is the longitute and the second the latitude (or vice-versa if you like).

Then I could feed each point into some function for which I wrote the code myself, getting a sequence of points on a plane, and my function determines what map projection it is.

Is the data---the sequence of pairs of coordinates described above---in some reasonable downloadable form on the web somewhere, for the continents and islads that would usually be clearly visible on a globe? Michael Hardy (talk) 23:28, 20 November 2012 (UTC)

NOAA World Vector Shoreline -- Finlay McWalterჷTalk 23:40, 20 November 2012 (UTC)

To give you an idea of how detailed NOAA-WVS is, this map is rendered from that dataset. You may find that WVS is far too detailed (and you can have lots of maths fun simplifying astonishingly detailed polygons to the desired resolution). -- Finlay McWalterჷTalk 23:52, 20 November 2012 (UTC)

They have less detailed maps too (scroll to the bottom). (Paraview fans click here). [1]. Need to reduce the complexity? GPSbabel uses the Douglas-Peucker algorithm to reduce the level of detail. Trio The Punch (talk) 23:49, 20 November 2012 (UTC)

I prefer GSHHS [2], which comes in several different resolutions depending upon need. Dragons flight (talk) 18:24, 21 November 2012 (UTC)

November 21

C++ constructors

Suppose that I don't want a subclass's constructor to call the superclass's constructor. I also don't want to make a fake superclass constructor. I believe that both are against my religion.. Is this possible? --140.180.241.187 (talk) 06:52, 21 November 2012 (UTC)

I am not sure I understand your question, but if I understand you right, then the answer is no. That is, the language is explicitly constructed to prohibit what you want to do.

I only have the 2003 language standard at hand. There is paragraph 4 from chapter 12.6.2 ("Initializing bases and members", [class.base.init]) which says that if a given base class is not named by the constructor init list of a constructor of a subclass, and the base class is a non-POD class, then the subobject inherited from the base class is default-initialized, i.e. the default constructor of that base class is implicitly called. Furthermore, by paragraph 5 from chapter 12.1 ("Constructors", [class.ctor]), if there is no user-defined default constructor and if the default constructor cannot be implicitly defined, the program is ill-formed.

Anyway, why would you want to leave the member variables that were inherited from the superclass uninitialized? — Tobias Bergemann (talk) 13:15, 21 November 2012 (UTC)

I've just had a quick look at N3337, the working draft most similar to the published C++11 standard. Here the situation is somewhat more complicated because now constructors can delegate their work to other constructors, but I think what I wrote is still true, see 12.6.2/8. — Tobias Bergemann (talk) 13:27, 21 November 2012 (UTC)

What is being talked about is a way of breaking the basic contract for use of a class. If a class is designed to ensure something then if it can just have everything zero because someone left out a constructor call then the whole basis of classes is broken as far as C++ is concerned. If you include the definition of the class in the same module or there is cross module optimization then there may be opportunities to inline any required work. Dmcq (talk) 17:52, 21 November 2012 (UTC)

32-bit or 64 ?

I just bought a Dell Optiplex 320 with Windows 7. I'm pretty sure that's the 32-bit version, but how can I tell for sure ? And does that model even support the 64-bit version ? StuRat (talk) 07:06, 21 November 2012 (UTC)

Control Panel > System and Security > System, I'm guessing from the screen print here. Ssscienccce (talk) 07:44, 21 November 2012 (UTC)

The tech spec [3] doesn't list Windows 7 as an OS, so it was probably installed by whoever he bought the system from. The CPUs listed all support 64-bit operating systems, but you'll have to check the system properties to know what version is installed. Windows key + Pause/Break is a quick key combination to bring it up. "System type" under the "System" section will tell you if it is 32 or 64. 209.131.76.183 (talk) 13:25, 21 November 2012 (UTC)

OK, thanks. It's 32-bit, as I suspected. StuRat (talk) 18:00, 21 November 2012 (UTC)

Update: whoever YOU bought the system from... I swear last time I read it I saw "My brother just bought", so apparently I am going insane. 209.131.76.183 (talk) 15:11, 21 November 2012 (UTC)

Must be, I never typed that. StuRat (talk) 18:00, 21 November 2012 (UTC)

Wikipedia has dangerous side-effects, we should have a warninglabel: "Warning: This website is highly addictive and may cause insanity". Trio The Punch (talk) 19:20, 21 November 2012 (UTC)

Converting a CTRL key into a FN key

I have a lovely new laptop. Its quite small so some keys have duplicate functions, eg the four arrow keys become, when FN is pressed, the HOME UP DOWN END keys. Unfortunately the FN is on the left hand side and the arrow keys are on the right hand side, so two hands are needed just to jump to the end of a page. The keyboard has two CTRL keys, one on either side. Would it be possible for me to convert the right hand CTRL key into a second FN key? I am running Windows 7 at the moment. At some stage in the future I'll be changing over to a Linux OS, hopefully almost-instinct 10:05, 21 November 2012 (UTC)

It may depend on the make and model, but this can often be done by changing a BIOS setting - e.g. see here. Googling "swap fn ctrl keys" gives lots of promising-looking links. AndrewWTaylor (talk)

Sorry, I misread the question - the link above is about swapping the left-hand Fn and Ctrl keys. AndrewWTaylor (talk) 12:52, 21 November 2012 (UTC)

Keyboardremapping is usually simple (KeyTweak) but the FN key on laptops is more complicated. Some models that have a [fn] key do send detectable messages when that key is pressed/released. However, these messages are not standardized between different devices and also, some devices with a [fn] key do not produce any message at all when the key is pressed (the key is handled at the hardware level on that device). Which laptop do you have? Trio The Punch (talk) 13:32, 21 November 2012 (UTC)

Its a Samsung NP530. Since [fn]+various other keys operates things like brightness and volume I can see why that key might be treated differently :-( almost-instinct 15:18, 21 November 2012 (UTC)

Yeah, just been looking in the manual for Keytweak: "Keytweak cannot affect the Fn key of most laptops. This because the Fn key itself does not generate a scancode, but rather modifies the scancode of other keys on the keyboard. The scancode modifications take place upstream of KeyTweak’s functionality". I think that draws this conversation to a close. Boo. Thanks for your time. Actually while I've got your attention.... Why when one's machine has a 128GB drive does the computer say "Total size: 92.3GB Space free: 64.7GB" I figure the difference between the two numbers is thanks to the OS and all the other preinstalled junk, but where's the other 35.7GB? Is the computer reserving that for its own purposes? almost-instinct 15:27, 21 November 2012 (UTC)

You may well be able to do this AutoHotkey. I've personally used it to do something very similar before. ¦ Reisio (talk) 18:08, 21 November 2012 (UTC)

Is the drive an SSD? Often, a significant percentage of a SSD's space is used for load-leveling. As cells in the memory are written and re-used, they slowly wear out. By swapping around where things get stored, the drive can be worn out evenly, so it lasts much much longer. This can only be done if there is enough unused space, so part of the capacity is reserved. The system may also have a hidden partition that is used for recovery. You can use disk manager (in computer management) to see if this is the case. 209.131.76.183 (talk) 15:59, 21 November 2012 (UTC)

It sounds like you have a recovery partition. It may be somewhat hidden. It contains a backup of the preinstalled OS and drivers. Trio The Punch (talk) 16:08, 21 November 2012 (UTC)

Try this trick, maybe you can get the keycode. If you press a button the site displays the keycode. Trio The Punch (talk) 15:51, 21 November 2012 (UTC)

The keycodes for the arrows are 37, 38, 39, 40. With the [Fn] key down that becomes 33, 34, 35, 36. With the right hand side shift key down they stay 37, 38, 39, 40. Perhaps I can reassign the shift+arrow keys to 33, 34, 35, 36. And simply forget about the [Fn] key, which (unlike SHIFT and CTRL) doesn't produce a keycode. Thanks for the links to that useful-looking software. I've a friend who will help me play around with it. As for the drive - yes its an SSD. I choose it because of the speed benefits - all my big files will living somewhere else - so I'm not fussed that its doing this in the interests of speed. Thank you for your thoughts on that too. You're all very lovely :-) almost-instinct 19:33, 21 November 2012 (UTC)

I will mark this as resolved since you seem to be on the right track, but feel free to remove the {{resolved}} tag if you have more questions. Trio The Punch (talk) 20:19, 21 November 2012 (UTC)

Resolved

XKCD

What does u+2o2e refer to here? Rojomoke (talk) 12:26, 21 November 2012 (UTC)

Unicode character 202e, RIGHT-TO-LEFT OVERRIDE, reversing the direction of character presentation. Graeme Bartlett (talk) 12:03, 21 November 2012 (UTC)

Unfortunately explainxkcd.com is not up to date. Trio The Punch (talk) 12:06, 21 November 2012 (UTC)

Thanks Rojomoke (talk) 12:26, 21 November 2012 (UTC)

To explain the joke... standing guy starts some boring rant, black hat switches direction so standing guy now speaks in reverse. Read it backwards for what he is saying (and see if you can spot the small error). Astronaut (talk) 12:42, 21 November 2012 (UTC)

explainxkcd.com is up to date if you know where to look (they should really update their home page..). AndrewWTaylor (talk) 12:47, 21 November 2012 (UTC)

No, it is not up to date, you just agreed with me by disagreeing with me. Let's get married! Trio The Punch (talk) 20:23, 21 November 2012 (UTC)

Off-topic: the reversed 'THE' is misspelled... --CiaPan (talk) 14:10, 21 November 2012 (UTC)

How, exactly, does one use this character? I've seen youtube videos get it from a character map; can it be done on a keyboard? I feel the answer must be "yes" because I've had it happen to me accidentally once or twice. 146.87.49.176 (talk) 14:16, 22 November 2012 (UTC)

Efficiency of bit serial CPUs for massively parallel High Performance Computing and graphic processing.

How do a Bit-serial architecture such as a Serial computer perform in in terms of operations per joule and operations per second and square millimeter chip area. I am speculating about a system with bit-serial CPUs integrated on memory chips, preferably DRAM memory. About 10 000 CPUs per GB memory. Given that they would only need a few thousand transistors per CPU this would be a small part of the chip area. Since each individual CPU is relatively slow it would not need cash memory or other optimizations such as out of order execution to hide the memory latency. These optimizations totally dominates the area and power consumption of a normal CPU. Could this be a reasonable approach? Gr8xoz (talk) 16:08, 21 November 2012 (UTC)

BTW, I wanted to help you cache your mistake. :-) StuRat (talk) 17:55, 21 November 2012 (UTC)

The problem is what would it be good for? There were a number of bit serial massively parallel computers around thirty years ago but for instance the ICL DAP had 4096 elements a 64x64 array which is a workable size. Much larger than that and there just aren't the problems that map properly without very much better interconnection. The later DAPs had a 8 bit processors and some local 8 bit memory rather than expanding the array. There's not really much point in using anything except a proper processor with floating point nowadays for a large array and for small arrays the effort of making them wouldn't be worthwhile for a manufacturer that I can see. So you'll need a killer application first. Dmcq (talk)

How about finite element analysis ? This only requires that each node interact with the adjacent nodes. StuRat (talk) 17:55, 21 November 2012 (UTC)

I think the wide market for powerful graphic cards and FPGAs show that there is a market for simple computing elements in parallel. GPUs are used more and more for general computing (GPGPU) applications. If a massively parallel bit serial design could be used as a GPU but use less power and be more flexible that could be a killer application. Other than that there are a lot of embedded applications that currently uses FPGAs to implement parallel computations. Some applications could be video/audio encoding/decoding, computer vision, data compression, scientific simulations and so on.

The ICL DAP had all elements work in lock step as a SIMD system, that limits the range of problems the system could effectively solve considerably. I actually think you equally well could define it as being a special 4096-bit CPU as 4096 1-bit CPUs. I was thinking about full CPUs with floating point operations in a serial implementation. Each CPU can access all memory but have fastest access to the 1 Mbit memory block that are closest. As I understand it the most costly part of a a system today is the data paths, not the logic and this minimizes data transfer. Since each CPU can operate independently with full memory access it is much more flexible than a GPU. The question is could it beat it on performance for a given power and chip area? Gr8xoz (talk) 20:41, 21 November 2012 (UTC)

If you have a full processor you might as well access a larger chunk at once. Memories nowadays return a number of bits at once, and allow the data close by to by accessed faster as the line it is in has already been selected and just a small chunk returned externally. By the way another problem to cope with is error detection, a major reason the DAP only allowed access to the same address in each processing element was so error detection could be across each row and column of the array rather than having anything within the elements. Dmcq (talk) 00:17, 22 November 2012 (UTC)

Yes a typical DRAM is organized in a number of matrices and access one row at a time, often a few hundred bits per row. The problem is that it takes about 10 ns to access one row. A parallel processor needs to wait or use a cache large enough to hide the latency. In that time the serial processor operating at lets say 2 GHz reads about 20 bits per channel, one channel per operand, one for instructions and writes out the result, in total 80 bits. The transfers would obviously go through a few shift registers holding a row of data each, acting as a micro cache of a few bytes. Normal computers does not have bit error detection hardware, some memories have but that could easily be implemented on the DRAM row level. The DRAM row length should be optimized with regards to the number of CPUs that likely tries to access the same memory matrix, their relative timing and the number of data channels and so on. Then of course the next question is how the different semiconductor processes would mix if it should be done on a single chip. Gr8xoz (talk) 01:17, 22 November 2012 (UTC)

Well actually the error detection is less important nowadays as one can replicate the difficult bits and detect errors that way. So you are actually talking about internally working in a bit serial fashion in the processors. The big problem with that is the multiplying, that takes time proportional to the square of the number of bits in a word. That I believe is why later DAPs had 8 bit local processors added. Dmcq (talk) 10:25, 22 November 2012 (UTC)

By the way Ericsson recently acquired a firm that designed something along the lines you are talking about - not integrated with the memory but no-one has bothered with that - the chips are used mainly for video compression. The search term for that sort of stuff is 'associative string processors' Dmcq (talk) 10:45, 22 November 2012 (UTC)

Yes serial operation internally and maybe more importantly in the routing system/buses that connects the CPUs to the memory matrices. The actual read out of a memory matrix is of course parallel. As I understand it there are a mainly serial implementation of multiplication that scales linearly with the word length in both time and number of gates, called serial parallel multiplier or something similar. A pure parallel implementation scales the number of gates as the square of the word length. I will look up 'associative string processors' later, I need to return to work from my lunch break now. What do you mean with "replicate the difficult bits and detect errors that way" do you talk about repeating important calculations and check that the results agree? Gr8xoz (talk) 12:18, 22 November 2012 (UTC)

By replicating I mean just duplicate the processor on the chip and compare the outputs, that way you can detect errors in the processors as well as the data. It can be cheaper than replicating all the hardware or running problems twice. Of course if you don't want any downtime duplicating or triplicating all the hardware is better anyway and you can get away with less hardware per processor for detecting errors. Dmcq (talk) 15:49, 22 November 2012 (UTC)

Partitioning hard disk in Windows 7

Is there a built-in utility to do this ? The 1 TB USB external hard drive in question is already partially occupied by movies, so I'd like to leave the occupied part in place. StuRat (talk) 18:20, 21 November 2012 (UTC)

http://technet.microsoft.com/en-us/magazine/gg309170.aspx Trio The Punch (talk) 19:14, 21 November 2012 (UTC)

Thanks. I tried that, but the "Shrink Volume..." option is grayed out for that partition, which is FAT32. The other hard disk can be shrunk, and is NTFS formatted. Is that the problem ? If so, am I just SOL ? StuRat (talk) 02:11, 22 November 2012 (UTC)

DiskPart is something of an underachiever (presumably to leave market space for the paid for disk partitioning software). You're probably better off booting your computer from a Linux live CD (ubuntu, fedora, debian, or gparted-livecd) and use gparted or KDE Partition Manager. 87.113.165.189 (talk) 02:31, 22 November 2012 (UTC)

I have Puppy Linux. Are either of those available on it ? StuRat (talk) 04:40, 22 November 2012 (UTC)

Do you have another drive that you could move the contents of that HD to, then repartition it, and then move them back? That would probably be safer. Bubba73 ^{You talkin' to me?} 06:24, 22 November 2012 (UTC)

I've used the partition editor in Puppy. I mostly works OK (I only had one instance of it screwing up the partition in some weird way). Like Bubba advisies, it is safer to back up to another disk first. Astronaut (talk) 18:33, 22 November 2012 (UTC)

How do I run the partition editor ? StuRat (talk) 15:49, 23 November 2012 (UTC)

Googling "puppy linux partition editor" indicates that Puppy Linux (like a large number of Linux variants) uses the Gparted partition editor. Either look for "Gparted" or "Partition Editor" in the system menu, or run the command "gparted" at the command prompt as root or with sudo. (It's a graphical editor, even if you launch it from the command line.) -- 205.175.124.30 (talk) 21:41, 23 November 2012 (UTC)

Thanks. Tried it, but the resize option is again dimmed out. Does resize not work on FAT32 partitions ? StuRat (talk) 23:45, 23 November 2012 (UTC)

The partition may be dirty; scan it with Microsoft ScanDisk and make sure to cleanly unmount it in windows. -- Finlay McWalterჷTalk 23:51, 23 November 2012 (UTC)

I couldn't find ScanDisk, but ran a defrag with no problems. That means it's "clean", right ? StuRat (talk) 15:28, 24 November 2012 (UTC)

And obviously make sure, if you're doing this in Linux, that all partitions on the target disk are unmounted. -- Finlay McWalterჷTalk 11:58, 24 November 2012 (UTC)

Hmmm, if the disk is unmounted, gparted's "Move/Resize" option is grayed out. If mounted, the option is lit, but only allows me to increase size, not decrease, for this partition. StuRat (talk) 15:44, 24 November 2012 (UTC)

How did the team making Eclipse (which itself is mostly written in Java) for Windows make it an exe?

I know there are various third party applications out there for turning Java programs into Windows runnable .exe programs, but how specifically did the folks that produce the Eclipse binary for Windows make that software an .exe and not a JAR? I read somewhere that Eclipse is built with PDEBuild, but it seems that that is something that uses Ant, which itself orchestrates the building of things Java, which doesn't answer the question (without plumbing the depths of PDEBuild source) how exactly at the root of it all Eclipse, which was built with PDEBuild, which used Ant, which ran javac commands, made an .exe file instead of a JAR. 20.137.2.50 (talk) 20:00, 21 November 2012 (UTC)

Eclipse starts from a native code launcher, Eclipse Launcher, the job of which is to find an appropriate JDK (or, I guess if you're not building for Java targets, a JRE) and launch javaw.exe. Doing this, rather than have the shortcut be to an invocation of javaw.exe, gives a bit of resilience (e.g. in cases where someone uninstalls the JRE) - it should give a more useful error report than "executable not found". That page shows how the IDE can be started manually with an invocation of the java executable, rather than using the native launcher. -- Finlay McWalterჷTalk 20:29, 21 November 2012 (UTC)

If I were an engineer there I would continually surprise my bosses with miraculous speed improvements to Eclipse's startup routine, i.e. what is available while launching, how soon it's available, how fast it is to interact with in the first few moments. I'd do this by slyly, slyly, ever so slowly, translating Eclipse into C++ and writing it into the launcher. The other teams wouldn't even notice until it was too late! since it's c++, they wouldn't even notice the modest size increase versus the rest of the bloated codebase! As they saw the C++-baesd launcher's footprint catching up with the rest of the project, their only thought would be "yeah, that was bound to happen eventually. wonder what took so long"? Little would they suspect that their precious Eclipse was about to be eclipsed. I would next perform a whole coup and having reimplemented all of of Eclipse with a faster C++ version right in the launcher program, I would simply stop launching Eclipse at all! People would catch on, and start downloading just the 'streamlined' launcher. Muhahahahaha. Step one: take over responsibility for maintaining the launcher. Step two: the world. --178.48.114.143 (talk) 21:32, 21 November 2012 (UTC)

Guess what! You can get started right now! Here's the Eclipse Platform common code repository. Chances are very high that you won't have permission to make a commit to the official repositories, but you're encouraged to clone the git repository. If your changes are an improvement, it's very likely that you can make a strong case for inclusion. If, however, your suggestion is to re-architect the core platform code without telling anyone, that's not very good software engineering. Good communication about the intent and implementation of program code is a prerequisite for effective professional software development. Making changes that you think are wonderful, without consulting the many other experts who have worked on the project for a long time, is not necessarily the best way to make improvements. Nimur (talk) 00:48, 22 November 2012 (UTC)

November 22

Mysterious Folders

On unhiding all hidden folders, I discovered that my flash drive has three hidden folders on it, named ".fseventsd", ".Spotlight-V100", and ".Trashes". Can I safely rename (or better yet, delete) these folders? Pokajanje|Talk 00:25, 22 November 2012 (UTC)

Yep, but I would recommend ignoring them. http://hostilefork.com/2009/12/02/trashes-fseventsd-and-spotlight-v100/ Trio The Punch (talk) 00:32, 22 November 2012 (UTC)

Alternative to Google Documents?

Are there any services similar to Google Docs that allows multiple users to edit a document and track changes to each user?

Is there a local network software that does the same thing as Google Docs sharing capability?

Cliffbament (talk) 15:40, 22 November 2012 (UTC)

Microsoft SharePoint will, but I think it has a clunky check-in, check-out type locking scheme. 87.113.165.189 (talk) 15:56, 22 November 2012 (UTC)

why is there no link between CAP theorem and Quorum?

How does Quorum (distributed computing) fail to negate the CAP theorem?

For example, given five known database servers I send my transaction request to all five at the same time.

As soon as I get a failed result from any of them I know that the transaction has failed and can report same.

As soon as I get a transaction acknowledgement from any three database servers then I know that the result is good and can report same.

In the meantime if I get transaction status unknown or insufficient responses I retry. Hcobb (talk) 17:38, 22 November 2012 (UTC)

You're confusing eventual consistency with immediate consistency; and along the same line of reasoning, conflating a retry-until-success with "availability." In such scenarios, although the system is functional for many practical use-cases, it is not complying with strict requirements of consistency, availability and fault-tolerance at every instant. Nimur (talk) 13:22, 24 November 2012 (UTC)

Then the CAP article isn't very clear. You could make a provably minimal quorum system in the sense that it transmits the least number of messages and still is as consistent and reliable as any possible scheme given X percent failures in the system. Hcobb (talk) 15:22, 24 November 2012 (UTC)

Scam or just desperate?

Okay, some lady, whom I appear to have no friends in common with, added me on Facebook. She has 12 friends, all of which are men. Since I accept just about anybody that isn't blatantly malicious, I accepted her request. Almost immediately she started talking about what she looks for in a man and asked what I look for in a woman. I tried to hint to her that I wasn't really interested in dating her, but she didn't seem to take that hint. She only made her account 2 hours ago, and while she says she is 20, the pictures she has posted look more like that of a teenager (if those are even really her pictures). On the other hand, she didn't seem to be afraid of the fact that I run spam traps and report spammers when I told her I have a Yahoo! account but it's a spam trap. She wants me to create a Yahoo! Messenger account and add her on Yahoo! Messenger. I tried to get her to message me via email (that would reveal an IP address), but that idea didn't work. The last thing she said to me was "okay baby". So is this some kind of scam to try and hack into my PC or is this just some desperate teenager looking for attention? PCHS-NJROTC ^(Messages) 19:27, 22 November 2012 (UTC)

Sounds a lot like a "flirty" chatbot. If you want to play along use a nonstandard chatclient, maybe they use a security flaw in Yahoo! Messenger. If it is a real person it may be a case of ewhoring. Google "ewhoring". Trio The Punch (talk) 19:41, 22 November 2012 (UTC)

This, perhaps. 87.112.97.202 (talk) 20:44, 22 November 2012 (UTC)

Well, I think it's definitely a real person behind it, otherwise it's one hell of a good bot that is able to comprehend what is written to it. I know this because I at first thought it might have been a Mafia Wars person or someone that followed me from Conservapedia (since it has a lot of politically conservative things liked)and had a little conversation with "it". Any suggestions for luring an IP address out of "it"? I want to have a little bit of "I know what you're up to and I have your IP address" fun with this "thing". Another thought is that, considering the seemingly phony conservatism that this person is pawning off, this could be some kind of attempt at Poe's Law PCHS-NJROTC ^(Messages) 22:48, 22 November 2012 (UTC)

I don't know if they fixed this security flaw, but back in 2009 you could simply use netstat-n while transferring a file. Use a proxy. Send him/her/it something, e.g. your favorite song. Or ask a random Wikipedian to host a file on a http server at a URL that has never been used before. Send the person the link, search the accesslogs of the http server. Trio The Punch (talk) 23:42, 22 November 2012 (UTC)

There's a fair chance it's neither. There are a variety of scams which don't involve any attempt at hacking. E.g. there's blackmail mentioned by 87 but also the sort of 'advanced fee' type of fraud where they'll convince you to give them money whether as a gift or to help them when for some strange reason the cops come after them or their relative gets sick or whatever nonsense. While the advance fee type of dating fraud tends to target dating websites, perhaps for some reason they think you're a suitable market. Nil Einne (talk) 07:54, 23 November 2012 (UTC)

Computer not automatically booting from the hard drive

The short: Boot device not found when i turn on the computer.

What works: Selecting the hard drive from the boot menu. Leaving a windows CD in the drive and letting it time out, which then boots the hard drive

What i have tried: Confirmed the hard drive(s) are seen in the bios, confirmed that the hard drive(s) are top of the boot list. Updated/re-flashed the bios. Modified boot sequence to HD > USB > CD > NIC > Floppy. Disabled USB, CD, NIC, & Floppy. Format/reinstall Windows 7. Format/reinstall Ubuntu 12.04. Grub repair off live CD on both Windows and Ubuntu. Tried 2 different hard drives. Tried the same with bootable USB with same results.

My temp solution is to just leave the win7 CD in the drive and let it time out which then boots the hard drive.

Any suggestions? Thanks.

Edit: Just to clarify; when i 'let the cd time out' what i mean is when it boots from the CD it said something like "Press any key to boot from the CD or DVD..." then after 5 seconds it decides i don't want to boot from the CD/DVD at which point it just boots from the hard drive. If the CD is not in the drive then i just get the error "No boot device found..." – Elliott(Talk|Cont)  21:08, 22 November 2012 (UTC)

Edit: Tested both hard-drives and USB flash drive on a different computer, and all 3 boot just fine (well, one hard drive BSOD when windows tires to load but that is to be expected as it wasnt installed on that hardware, and the other one boots in to ubuntu just fine, as does the USB drive.) – Elliott(Talk|Cont)  21:52, 22 November 2012 (UTC)

Could the issue be that the hard disk takes some time to show up ? I have an external hard drive like that. When I first turn it on, I might as well go get a cup of tea while I wait for it to appear. So, by the time you wait for the time-out, it may then be visible to the PC. I think the long lag for some hard drives might be because they are huge (TBs) and feel the need to do some type of startup test (obviously it can't test every bit, but maybe it tests one bit on each sector or some such thing). StuRat (talk) 06:30, 23 November 2012 (UTC)

That might be it, however 1 hard drive is 80g while the other is 200g – Elliott(Talk|Cont)  06:41, 23 November 2012 (UTC)

Is there any difference between a cold start (PC off over night) and a warm start (reboot) ? StuRat (talk) 06:56, 23 November 2012 (UTC)

Same result either way. – Elliott(Talk|Cont)  14:09, 23 November 2012 (UTC)

If it's a time-out issue, does disabling quick POST help? I.e. enabling the complete RAM scan, which would give the drive enough time to rev up and do its own POST? BTW, you did not say the PC booted from DVD when DVD was disabled in the BIOS? You tried disabling DVD etc. but you had to re-enable DVD to use the DVD trick?

Since one of the PCs is to "blame", maybe reset the BIOS to factory settings? I had to do that once in 2 months on one PC, it seemed that BIOS settings got messed up there to a point where it wouldn't boot any more.

Could you tell us what caused the problem to show up? Did the PC refuse to boot when you got it, or did it only happen after a certain change? (I'd guess it could be grub, but that's only a guess. One of my coworkers had a nasty grub fail once. Why that doesn't show up on the other PCs is beyond me, tho.) - ¡Ouch! (^{hurt me} / _{more pain}) 08:30, 27 November 2012 (UTC)

Saving modified SmartArt in PPT 2010

I am running Microsoft Powerpoint 2010 on Windows 7. I am using the SmartArt graphics that came with the software to create organization charts and have modified the color scheme and gradient for some of the elements. Is there anyway for me to save what I have modified as a custom SmartArt style so that I don't have to repeat all the modifications for every subsequent chart? Also, it will allow me to re-use this custom smartart for other presentation files. Thanks. Acceptable (talk) 21:29, 22 November 2012 (UTC)

November 23

sentence syntax program

I am looking for a program which I can use to signify sentence syntax above the words. --82.81.171.245 (talk) 09:39, 23 November 2012 (UTC)

Here are several programs that might be useful: http://ai.stanford.edu/~rion/parsing/index.html Unfortunately they are all fairly technical and might not be exactly what you are looking for. KarlLohmann (talk) 16:42, 23 November 2012 (UTC)

Java J2EE can a program check whether a user would be able to access a URL?

If I have various web resources protected by <security-constraint> entries in the web.xml is there a way to check whether a logged-in user would be able to access a particular URL? It would be useful to display links conditionally so that the user can only see URLs that they could access. -- Q Chris (talk) 12:04, 23 November 2012 (UTC)

This is a tricky one. I have written a (1)program in java that does check if the logged in user can edit the video being looked at (for youtube), however this was done by having my program login for the user. What i think your asking is if your program can assume the ID of the user and test his credentials against another website. However, if you can make the user login though the java program then u can store his information (temporarily) and use that to test the other websites. – Nerd(Talk|Cont)  18:02, 25 November 2012 (UTC)

Any webmail services that do not show real names?

I'm trying to find a webmail service that I could use for Wikipedia email. The problem is, that I apparently cannot completely hide my real name from being disclosed somewhere. The "send mail as" feature from GMail only works partially, as when you hover over the nickname, it still shows the real name. I know I could put a fake name in, but that just doesn't seem right. Any advice? Klilidiplomus+Talk 12:27, 23 November 2012 (UTC)

I use gmail with GishPuppy] to hide my ID. -- Q Chris (talk) 13:00, 23 November 2012 (UTC)

As a word of caution, do not rely on what you may or may not see when you hover over something or what is otherwise exposed via the UI. Instead look at the entire original email (e.g. via the 'show original' function in most webmail services) and make sure there's nothing revealed that you don't want to be revealed. For example gMail won't generally publicly reveal the IP of the computer used to send the email, IIRC even if you use the SMTP service which I presume Q Chris is doing, but many webmail services and many ISP servers will. Nil Einne (talk) 13:42, 23 November 2012 (UTC)

I am still worried about when sending an email to someone that also has a Gmail account using Wikipedia's email feature. Klilidiplomus+Talk 15:07, 23 November 2012 (UTC)

I don't really get what you mean. If you are using an email account which is publicly associated with your real name, then finding a way to hide the real name in the gmail is clearly utterly pointless. If you are concerned that Google is going to reveal your real name without your permission then either choose a different provider or use an account with a fake name. Nil Einne (talk) 12:18, 24 November 2012 (UTC)

I don't see the problem with creating a 2nd, anonymous Gmail account. The "fake name" can be something like "Prefer Anonymity". You might be able to set this account up to forward mail to your regular Gmail account. StuRat (talk) 15:45, 23 November 2012 (UTC)

@StuRat There are some people who will never lie (even to a machine) for religious or moral reasons. Klilidiplomus has asked for a way to do it without giving false names and clicking terms and conditions which say that you will not use false names. I think we should give him ways to do that. -- Q Chris (talk) 15:59, 23 November 2012 (UTC)

It isn't lying when you make it clear it's not your name, and that the reason is that you prefer anonymity. StuRat (talk) 23:53, 23 November 2012 (UTC)

Google "anonymous email" you'll find a lot of websites like this one and that one. You can test them by trying it on yourself first. You can check the source of the email you received to make sure there is no identifiable info. If you need to send an attachment try Amnesty. Trio The Punch (talk) 17:07, 23 November 2012 (UTC)

It might not seem right to use a fake name for gmail, but it's a good idea to, whether you actually send email or not (because historically you do not even have to send email for people to get to that information). ¦ Reisio (talk) 17:37, 23 November 2012 (UTC)

Brute force Ingress invitation code?

Is there some way I can brute force an Ingress invitation code? I believe they're 8-characters in length. — Preceding unsigned comment added by 78.144.193.174 (talk) 21:58, 23 November 2012 (UTC)

Only if the system accepting input is poorly written. ¦ Reisio (talk) 22:51, 23 November 2012 (UTC)

Sharing bookmarks ?

Is there any way to share bookmarks/favorites between my various web browsers ? I use Firefox, Opera, Chrome, and, if need be, even IE. I'd like to keep the same bookmark structures in each, so that when I add a bookmark to one, it appears in the rest, too. Just exporting and importing them would be rather painful, since, even if it worked, this would require me to import into the other 3 every time I add a bookmark. StuRat (talk) 23:52, 23 November 2012 (UTC)

Xmarks (no Opera support). Google "sync bookmarks between browsers". Trio The Punch (talk) 02:22, 24 November 2012 (UTC)

November 24

Windows 8 fast startup feature

What could cause the fast startup feature in windows 8 to stop working if it worked fine before? 176.248.109.88 (talk) 01:16, 24 November 2012 (UTC)

talking only from my personal and short experience, I think the only thing the fast startup feature actually do is to hibernate the pc instead of turn it off… I realize that by the lcd built-in in my board …so, maybe if you deactivated the hibernate function of your system that could be the reason.

Iskánder Vigoa Pérez (talk) 20:47, 24 November 2012 (UTC)

MSIE 8 on XP

I run MSIE 8 on XP. When I have multiple browser windows open and one or more is slowly loading content, it often keeps putting itself as the top window. Is there a way to stop it doing this and to have the window I have selected stay as the top one? -- SGBailey (talk) 13:16, 24 November 2012 (UTC)

TweakUI is your friend. Download it and try this. Apparently it doesn't happen if you open separate threads, it only happens if you open a new window from an existing thread/process (e.g. via right click "open in new window" or ctrl+n). Trio The Punch (talk) 15:43, 24 November 2012 (UTC)

The best thing you can do is to install chrome or firefox.

Iskánder Vigoa Pérez (talk) 20:45, 24 November 2012 (UTC)

I agree with Iskánder, IE is a bad browser, and the alternatives are free. Trio The Punch (talk) 03:59, 25 November 2012 (UTC)

Weird C++ linking problem at work

I am facing a really weird C++ linking problem at work.

The basic idea is this. We are working on a Windows application (I am using Windows 7 on my work computer). I am running Visual Studio 2008 and Xoreax IncrediBuild as a distributed compiler on top of it. We have developed a Windows native C++ library, and I want to create a Managed C++ wrapper on top of it so it can be called from C# code.

The code compiles but does not link. I get linker errors about undefined external symbols for numerous functions in the native C++ library that are both declared and implemented in the library code. I have found out that these all come from functions that call functions from other objects, where the functions are both declared and implemented in the .h file. If I move the implementation to the .cpp file, the code links OK.

As an example, this doesn't work:

StdAfx.h in my wrapper:

#include "NativeLibrary.h"

NativeLibrary.h:

#include "Inner.h"
class Outer
{
  public:
    int GetMagicNumber() const
    {
      return myInner.GetMagicNumber();
    }
  private:
    Inner myInner;
};

Inner.h:

class Inner
{
  public:
    int GetMagicNumber() const;
};

Inner.cpp:

int Inner::GetMagicNumber() const
{
  return 42;
}

But it does work if I change NativeLibrary.h to this:

NativeLibrary.h:

#include "Inner.h"
class Outer
{
  public:
    int GetMagicNumber() const;
  private:
    Inner myInner;
};

NativeLibrary.cpp:

int Outer::GetMagicNumber() const
{
  return myInner.GetMagicNumber();
}

Does anyone have any idea what is going on here? JIP | Talk 15:30, 24 November 2012 (UTC)

I tried your not working code in g++ (as it's often instructive to use another compiler). My only observarions:

• I had to add #include "Inner.h" to the top of Inner.cpp (perhaps you just didn't cut and paste that)
• I wrote a simple main.cpp:

#include <iostream>
#include "NativeLibrary.h"
int main(){
  Outer o;
  std::cout << o.GetMagicNumber() << std::endl;;
  return 0;
}

(which I guess is what you intended).

• That all compiles, links, and runs fine in g++

-- Finlay McWalterჷTalk 16:37, 24 November 2012 (UTC)

If your Inner.cpp really didn't #include inner.h, I think it should. To my mind, for both c and c++, modules should #include their own public interface, so you will get a compile-time error if you inadvertently change the signature so that the definition doesn't match the declaration. If you do allow that error to happen in C++, and you compile one .cpp but not the other, you may get a link error due to the differences in name mangling. -- Finlay McWalterჷTalk 16:47, 24 November 2012 (UTC)

Yes, Inner.cpp #includes Inner.h and NativeLibrary.cpp #includes NativeLibrary.h. I just forgot to write it in the above example. Maybe this is specific to Visual Studio 2008 and Xoreax IncrediBuild. What is weird here is that the native library compiles and links fine by itself, but my wrapper which calls the library compiles, but does not link, even though all the symbols I get linker errors about are declared in the native library. JIP | Talk 16:59, 24 November 2012 (UTC)

Then I'd again suspect name mangling. In addition to mangling names to encode C++ information, Microsoft compilers also add in stuff for the calling convention (for example, win32 API calls are FAR PASCAL, and are mangled as such). When cross language calling one has to take this into account, and you may have compiler settings that are using a default that makes the imported symbols mangle differently than those exported. You should be able to run DUMPBIN.EXE on the object files to see what the mangled names are. -- Finlay McWalterჷTalk 17:55, 24 November 2012 (UTC)

Just a note, mostly for posterity. I'm wrong about win32 (and showing my age): X86 calling conventions shows that win16 calls were FAR PASCAL but that win32 calls are STDCALL. -- Finlay McWalterჷTalk 15:54, 25 November 2012 (UTC)

sentence syntax program (Continuation(

I dont look for "parser online" or programs that parser sentence .I am looking for a program which I can use to signify sentence syntax above the words.thanks --82.81.171.245 (talk) 18:17, 24 November 2012 (UTC)

I take it you are looking for something like this:

<font=Courier>

....A..............................A....A 
....D..............................D....D   
A...J.........................A....J....J    
R...E.........A...........A...R....E....E    
T...C.........D...........D...T....C....C    
I...T...N.....V......V....V...I....T....T....N
C...I...O.....E......E....E...C....I....I....O
L...V...U.....R......R....R...L....V....V....U
E...E...N.....B......B....B...E....E....E    N

A brown fox quickly jumped over the slow, lazy dog.

(I haven't diagrammed a sentence for decades, so I hope I did it right.) If this is what you want, try "diagram English sentence online" for your search.

The periods are just added because Wikipedia wants to make spaces narrower than characters (on my browser, at least). What's the proper way to stop this ? StuRat (talk) 15:51, 25 November 2012 (UTC)

Lenovo ThinkCentre's eSATA port

Dear Wikipedians:

Is it just me or has anyone noticed that Lenovo ThinkCentre (desktop)'s eSATA port in the back is extremely unstable? I plugged in an eSATA hard drive with the hope of booting from it, but about half the time ThinkCentre failed to pick up the hard drive and it doesn't show up in the boot menu. By comparison, the front panel USB port marked "1" seems much more stable.

What gives?

Thanks,

70.31.154.178 (talk) 23:06, 24 November 2012 (UTC)

Link dump: http://support.lenovo.com/en_US/detail.page?LegacyDocID=SF09-D0099 Hcobb (talk) 23:57, 24 November 2012 (UTC)

Thanks. 174.88.154.30 (talk) 17:00, 25 November 2012 (UTC)

Without knowing stuff like how many different cables you've tried and how many different drives you've tried, the amount of useful information we can provide to you is close to zero. Nil Einne (talk) 14:14, 25 November 2012 (UTC)

Sorry, allow me to elaborate. I have a standard desktop SATA hard drive that I have put into an external hard drive enclosure made by Vantec. I will get back to this post with detailed model and make information once I get back to Kingston. The eSATA cable was the default one that came with the enclosure. It is a grey-colored eSATA cable. The external enclosure is capable of both eSATA and USB connections. 174.88.154.30 (talk) 17:00, 25 November 2012 (UTC)

November 25

What is the current standard for form descriptions?

Is Extensible Forms Description Language the standard or is there a new one. I'm actually looking for a definition language for which a user friendly editor is available, that can be compiled to a web form, for which an open source library is available. And most importantly, has a DotNet WinForms implementation so I can show the form directly in an application. Thanks! Joepnl (talk) 15:41, 25 November 2012 (UTC)

A bit more information: there are lots of validated surveys to score a subject (quality of life, eyesight, etc). I'm looking for a standard format which these questions would fit in. Joepnl (talk) 17:42, 25 November 2012 (UTC)

2.0 Megapixel cell phone camera ?

I bought a Samsung 425G cell phone. The manual says it has a 2.0 Megapixel camera, see page labeled 177 (actually page 121, counting the unnumbered forward pages) here: [4]. The camera settings allow for a max resolution of 320×240, which, by my calculations, means 0.0768 Megapixels, or 1/26th what they advertised. Why the huge discrepancy ? My guess is that they mean 2.0 Megabits (not Megabytes or Megapixels), and that they are using 24-bit color. However, the advertising clearly says Megapixels, not Megabits. So, did they screw up the advertising big time ? StuRat (talk) 16:21, 25 November 2012 (UTC)

Many cameras record video at a much lower resolution than they will take still images (because their CPUs can't compress full-resolution video in real time, and/or because the bandwidth of their serial flash memories isn't fast enough to store it). Are you sure that you can't take stills at 2 Megapixels? -- Finlay McWalterჷTalk 16:28, 25 November 2012 (UTC)

Yea, that must be it. I see where it says in the manual it supports resolutions up to 1600×1200. Apparently the settings are just in the wrong places, with the video res showing up under the options for the stills. I haven't found where you set the still resolution yet. StuRat (talk) 16:37, 25 November 2012 (UTC)

It should be in the camera mode options screen. Note from the later using the camcorder section that camcording is a mode of camera; if you're only seeing resolution options 174x144 or 320x240, then you're in camcorder mode and need to get back into camera mode (which is an option in that same menu). -- Finlay McWalterჷTalk 16:41, 25 November 2012 (UTC)

Thanks. StuRat (talk) 16:51, 25 November 2012 (UTC)

Resolved