Wikipedia:Reference desk/Archives/Computing/2010 May 2

= May 2 =

Full employment theorem for size-optimizing compilers
From Full employment theorem:
 * For example, the full employment theorem for compiler writers states that there is no such thing as a perfect size-optimizing compiler, as such a compiler would have to detect non-terminating computations and reduce them to a one-instruction infinite loop. Thus, the existence of a perfect size-optimizing compiler would imply a solution to the halting problem, which cannot exist, making it an undecidable problem.

Does this theorem still apply if we require the compiler to optimize the sizes of only programs that do eventually halt, and accept suboptimal output for programs that don't halt? Also, is it possible to optimize for execution time with the same limitation? Neon Merlin  00:48, 2 May 2010 (UTC)
 * A program that satisfies your modified requirements doesn't exist—it's existence would contradict the non-computability of Kolmogorov complexity. --98.114.146.58 (talk) 07:38, 2 May 2010 (UTC)

Ubuntu 10.04 and Nvidia failures
I just upgraded to Ubuntu 10.04 and immediately ran into a serious problem. While booting up, about 15 seconds in, the screen does a bit of blinking and then pops up an error message saying

Ubuntu is running in low-graphics mode The following wrror was encountered. You may need to update your configuration to solve this. (EE) NVIDIA: Failed to load the NVIDIA kernel module. Please check your (EE) NVIDIA:   system's kernel log for additional error messages. (EE) Failed to load module "nvidia" (module-specific error, 0) (EE) No drivers available.

All that is in a gray box on a black screen; there's a cursor in the middle of it that doesn't move when the mouse does; there's an "OK" button on the bottom right of the box. Nothing I do to the keyboard has any effect; the only thing that I can do at that point is reboot.

When I boot up in recovery mode, I can get a TTY screen and do command-line interaction with my machine, terminal style; however, when I try to start an X session, I get error messages stating the same thing as above. What should I do?

If it's pertinent, the computer is a System76 Bonobo laptop on an Intel Core 2 Duo. --72.197.202.36 (talk) 03:40, 2 May 2010 (UTC)
 * Ubuntu has changed the drivers it is using for NVIDIA cards by default, so this might cause some breakage. Do you have the nvidia-glx-185 package installed?  You probably will, but you can try

sudo apt-get install nvidia-glx-185


 * from the command line to make sure. I think this is the package for your computer. You can also try installing the third party NVIDIA drivers. The NVIDIA site isn't easy to navigate from a command line interface, but this seems to be the right link for now. From a command line try this

wget http://us.download.nvidia.com/XFree86/Linux-x86/195.36.24/NVIDIA-Linux-x86-195.36.24-pkg1.run


 * to download the driver (I think this is the one you would want), and then

chmod 755 NVIDIA-Linux-x86-195.36.24-pkg1.run ./NVIDIA-Linux-x86-195.36.24-pkg1.run


 * to install. It may not be an ideal solution, but it might get X working well enough for you to investigate further. Winston365 (talk) 04:31, 2 May 2010 (UTC)


 * Have you tried booting the computer with a Lucid live cd? It could help figure out whether it is an upgrade problem, or a problem with Ubuntu 10.4 itself. Winston365 (talk) 05:13, 2 May 2010 (UTC)


 * I would have used a CD if the computer would communicate with the CD drive, but for some reason, it doesn't do that in the TTY interface. --72.197.202.36 (talk) 21:19, 2 May 2010 (UTC)


 * When you are in the TTY interface you may have to mount the CD drive explicitly to use it, but that's not quite what I meant. The Ubuntu install CD should work as a live CD as well, ie you can boot the computer directly off of the CD. You may have to hit a button (F10 or something) when booting, or change the BIOS settings, to boot from a CD, but many computers will automatically ask you if you want to boot from the CD drive if a bootable CD is detected. Winston365 (talk) 03:04, 3 May 2010 (UTC)

I just tried to install the driver using Winston365's method. It told me that it couldn't find the nvidia kernel's directory source tree. Now what should I do? --72.197.202.36 (talk) 21:19, 2 May 2010 (UTC)
 * As for the error about finding the kernel's directory source tree, you may need to install the kernel source. Try

sudo apt-get install linux-source
 * Hope this helps. Winston365 (talk) 03:04, 3 May 2010 (UTC)

Unfortunately, it does not. I'm getting the same error message. --72.197.202.36 (talk) 20:11, 4 May 2010 (UTC)
 * Poop. The last suggestion I have is to install the nvidia-settings package, as shown here. I don't have a system with a nvidia chip to play with though, so I can't help much more though. Have you tried searching or asking at the Ubuntu Forums? Winston365 (talk) 21:36, 4 May 2010 (UTC)

PHP per-user server-side caching
In PHP when using the session module, can I tell the httpd to cache a separate copy of a page for each session? Can I clear the cache for a session ID early without ending the session (e.g. when the user has updated her preferences) from PHP even if I don't control the httpd? Neon Merlin  05:18, 2 May 2010 (UTC)
 * A bit unclear as to your question, can you provide another example? --rocketrye12talk/contribs 22:29, 6 May 2010 (UTC)

downloading in google chrome
when u download in google chrome, there's this download page which keeps track of all the downloads you do. but, suppose, let's say, you are downloading something, and halfway through, there's a powercut. so your download gets cancelled and you have to start all over again. it happens with me very often. so, can anyone help me find some software which would resume the download when i restart my computer?? plz i seriously need help on this!!! —Preceding unsigned comment added by 117.197.247.250 (talk) 09:35, 2 May 2010 (UTC)


 * Do you get power cuts often? I didn't think they were a particularly common occurrence. I'm guessing you're using a desktop computer because if you were using a laptop with a charged battery you could still use it for a while during the power cut until the battery runs down. As to software to try and resume downloads, I can't say I've heard of anything like that, short of having to go back and download again. Chevymontecarlo . 09:54, 2 May 2010 (UTC)


 * There are a variety of download managers which will resume an interrupted download. I'm sure Comparison of download managers will guide you to a suitable tool for the job.  Astronaut (talk) 10:44, 2 May 2010 (UTC)


 * Note that many downloads want to send you their own download manager first, then use that to do the download. You can tell because it's a two-step process, with the first step asking if you want to store the download manager or run it immediately (although it isn't always obvious from the name of the file). StuRat (talk) 12:49, 2 May 2010 (UTC)

Average lifespan of an external hard drive
How long on average would an external hard drive be expected to last before it failed? Chevymontecarlo. 09:56, 2 May 2010 (UTC)


 * Most drives have a mean time between failure rating which you can look up to get an idea of its reliability. However, it sounds like you're looking for something different: if I understand correctly, MTBF only applies in the middle of the bathtub curve, when the drive isn't so new it's liable to fail due to manufacturing defect, nor so old that it's in danger of wearing out.
 * One random source lists the conventional wisdom answer as being five years. I would not be surprised if different manufacturers and models have lifespans a factor of five different in either direction.  Our hard drive failure article has a link to a paper by Google, which found that their drives had a steady failure rate of 2% per year, which jumped to 6% after two years.  It has more details if you want them.
 * Public service announcement: a large proportion of hard drive failures happen in the middle of the drive's life. Be sure that your important information is backed up. Paul (Stansifer) 13:00, 2 May 2010 (UTC)


 * This usually depends on a few things -
 * All hard drives have a manufacturer's lifespan in hours which is in turn affected by a few things:
 * Device usage - if it is permanently on, it will shorten life (i.e. use up more of the "lifespan hours"
 * Device portability - 2.5" portable drives which are chucked in a bag, or 3.5" which are regularly carried will decrease life slightly, but moving whilst turned on will decrease significantly (-2/3 years)
 * Manufacturer - some are slightly more reliable than others - average life is asertained usually by the warranty they provide.
 * Size - there is shown to be a significant link between increased platters and increased failures - 500GB tend to be more reliable than 2TB. (-1 year)


 * So going on rough data - a 2.5", regularly moved whilst working, with v, heavy usage would be 2 years or less
 * A 3.5" 500GB turned on once a month to make a backup and stored at ambient temperature could be expected to last up to 10+ years.
 * These are mostly best estimates. For long term storage tape drives and archive dvds are recommended over hard drives, and regular backups should be made of all important data.


 * CmdAltDel (talk) 13:04, 2 May 2010 (UTC)


 * Keep in mind that cheap 3.5" external enclosures tend to have lousy cooling, partly to reduce cost, partly because home and office users don't like noisy devices (cooling fans make noise). They are intended mostly for taking occasional backups.  Yes, back everything up.  You have to think of hard drives as being like light bulbs--it's a question of "when" they will fail, not "if".  If you use a 3.5" external then get a model with low power consumption (runs cool) even if it's slower. 69.228.170.24 (talk) 14:54, 2 May 2010 (UTC)


 * But, the Google paper that was linked to above notes: The figure shows that failures do not increase when the average temperature increases. In fact, there is a clear trend showing that lower temperatures are associated with higher failure rates. Only at very high temperatures is there a slight reversal of this trend.  Comet Tuttle (talk) 15:20, 2 May 2010 (UTC)


 * Thank you! :) Chevymontecarlo . 11:33, 4 May 2010 (UTC)

A general purpose language
I used to use BASIC in the past, now I would like to learn another language. Is there a language which can a) be used to write software applications, b) be used to write web applications on websites, and as a bonus if possible c) be used for scripting? I'd prefer something that could be used on both Linux and Windows. Thanks 89.242.97.110 (talk) 11:23, 2 May 2010 (UTC)
 * Pretty much any scripting language fits those requirements (the ease of (a) and (b) varies, but it's always certainly possible). I think that Python is a good choice for an early language to learn, and it's popular for both (a) and (b).  Good luck!  Paul (Stansifer) 12:41, 2 May 2010 (UTC)


 * I usually shill the C# language. Comet Tuttle (talk) 15:18, 2 May 2010 (UTC)

How many or what proportion of websites are written in Python? 92.28.253.63 (talk) 10:29, 3 May 2010 (UTC)
 * It's really hard to define "website" in a way that a census would be meaningful. Consider the hundreds of domains of the form   that all run the same software (and the thousands of unaffiliated MediaWiki installations all over the web), or the totally different applications between   and  .  Also, it's very common for an application to be written in multiple languages, and the authors don't always reveal any information about this question.  So all we can say is "many".  Paul (Stansifer) 16:59, 3 May 2010 (UTC)

I thought it would be easy to tell just by looking at the source code? What have I got wrong? Thanks 92.29.62.241 (talk) 19:08, 4 May 2010 (UTC)
 * The "view source" tool in your browser shows the HTML source that defines that particular page. The web application is a program that sits on some other server and generates HTML (HTML is its object language).  You can't access its source code, unless the authors have intentionally provided it (for example, the aforementioned MediaWiki is free software).  Paul (Stansifer) 23:20, 7 May 2010 (UTC)

PHP question
How are php scripts on servers able to do tasks even when no one is accessing the script? For example, say there was a php script update a html page every 10 mins. How would the script execute without anyone going to it with their browser? 82.43.89.71 (talk) 13:05, 2 May 2010 (UTC)


 * Usually it is launched by cron or something similar (often known as a "cron job"). --Mr.98 (talk) 13:36, 2 May 2010 (UTC)


 * It is also probable that background jobs are not designed in PHP. While PHP is a great, flexible, powerful language, and is capable of doing just about everything any other programming language can do, it isn't really intended to be running stuff in the background.  It is a "Hypertext Preprocessor" and really is only designed be a server-side script to format HTML.  Nimur (talk) 13:46, 2 May 2010 (UTC)


 * Additionally to cron jobs, php files can be triggered to run by other files, for example bash script files, and more commonly python coded files. More commonly though a php file does not actually update the html file - the php file only generates the file when someone accesses it from the internet, the content which the php file updates the file with is most often stored in a database which has been placed there by another program. Updates for when a page is not loaded are instead carried out by ajax -- CmdAltDel (talk) 16:30, 2 May 2010 (UTC)

Thanks 82.43.89.71 (talk) 16:52, 2 May 2010 (UTC)

Words in browser keep being highlighted
I'm using Firefox and WinXP, and words or sections of text are being highlighted today when I move the cursor. The highlighted words are near the cursor. It still happens after going to another webpage, and when I click the left-mouse button. However, after clicking the button three or four times the highlighting disapears for a while. How can I cure this please? Thanks 89.242.97.110 (talk) 13:18, 2 May 2010 (UTC)


 * Try clicking the scroll-wheel if you mouse has one? My PC at work gets stuck in this sort of mode and that often fixes it. Similarly i've found holding the right-mouse button down and clicking the left-mouse button often stops minor clicking/viewing issues for PCs. ny156uk (talk) 14:36, 2 May 2010 (UTC)

I do not have a scroll-wheel but shall try the other suggestion when it happens again. Thanks 89.242.97.110 (talk) 21:33, 2 May 2010 (UTC)


 * I had never experienced this problem but it sounded to me like your left mouse button is getting stuck sometimes. I would try a different mouse and see if the problem goes away.  Comet Tuttle (talk) 02:41, 3 May 2010 (UTC)

large enough computer system or network
Where can I find a computer system of network large enough to run a Visual basic script now running as an asp script on my IP's server? The problem is primarily due to the amount of time and memory to generate and process an array which is 3^9 square. 71.100.1.71 (talk) 14:52, 2 May 2010 (UTC)


 * 3^9 square, you mean 3^18 which is about 390 million? What is the application?  Your first bet is to solve the problem in a different way that doesn't use as much memory, and my first guess is your problem doesn't really require that much.  But most servers these days have about the same capacity as personal computers.  A pc with 4gb or 8gb of ram is nothing special these days.  Personal computer cpu's are generally about as powerful as server cpu's too.  69.228.170.24 (talk) 15:01, 2 May 2010 (UTC)
 * The problem is the array size limit imposed by most server and PC VBS compilers so an alternative might be to re-write in machine code or to find a way to open up the limit set by the compilers for VBS arrays instead of searching for a larger system with a compiler that would do this anyway but I do not want to re-write in machine code and instead want to do away with the limit imposed on what I've got. 71.100.1.71 (talk) 15:21, 2 May 2010 (UTC)


 * A 2 dimensional array of ints 20000 by 20000 runs quite happily when compiled on C# on my PC. I would think it would be just as happy under VB.Net.  You could grab Visual Studio Express as a free M$ download and re-implement the code in .Net? --Phil Holmes (talk) 16:00, 2 May 2010 (UTC)
 * To overcome the possibility of a 64k array limit, possibly, but my experience with VB 2005 was not good. 71.100.1.71 (talk) 16:49, 2 May 2010 (UTC)


 * A better approach would be to change your algorithm so it doesn't use big arrays. Do you really fill each cell with something?  If memory is actually the problem then the first thing to try is storing the data more efficiently.  Comet Tuttle (talk) 16:16, 2 May 2010 (UTC)
 * I'm toying with the idea of:
 * creating independent cells with their own code which would look for and react to their precedent and dependent cells according to progression and status of the problem.
 * numeric rather than string manipulation.


 * I really want to try running the existing program on a larger or unlimited system first. 71.100.1.71 (talk) 16:49, 2 May 2010 (UTC)


 * Can't you just run it off of your local computer? If I understand you right you are saying the problem is not VBS's inherent array limit (which is (2^31)-1, much larger than your request), but server settings. Why not just set it up on your own, local computer as the "larger or unlimited system"? --Mr.98 (talk) 19:58, 2 May 2010 (UTC)
 * No, what I'm saying is that an array limit for VB is 64K not (2^31)-1. Server side asp also has a server timeout limit well under what it would take to get the job done. 71.100.1.71 (talk) 21:04, 2 May 2010 (UTC)

No leads or ideas of a large enough system where I can run this program? 71.100.1.71 (talk) 21:09, 2 May 2010 (UTC)


 * I've told you. On your own PC, using .Net.  It's not a large program - it barely scratches the surface of what a desktop will run.  --Phil Holmes (talk) 21:22, 2 May 2010 (UTC)


 * To start off with there are currently 6 versions of VB.NET. While Visual Basic Express 2005 came with a Visual Basic v6 converter there were so many changes required to implement conversion that re-implementation was not an option. While the matrix dimensions (number of cells) is 3^9^2 or 387420489 cells each cell is 256 bytes, just for this one problem. Not only that but it would take a 3 gigahertz quad processor personal computer about 6 months to look at all the data. So while VB.NET might be a small program and it might process a 20000 x 20000 matrix on your PC, it's use is not an option for my project. 71.100.1.71 (talk) 00:58, 3 May 2010 (UTC)


 * I am a little confused here. After re-reading the thread, it sounds like your complaint is that Visual Basic 2005 doesn't allow arrays large enough for this legacy application of yours to function adequately, because you want bigger arrays.  In that case, getting a "large enough system" won't help, because the limitation being discussed is the Visual Basic 2005 limitation, right?  Or are you asking whether there is some compiler available that will compile VB 2005 source code, without the array size limitation?  I don't see how a "larger system" helps you, in particular, here.  You could google high performance computing rent, but most of that stuff is for simulating the weather and such.  Comet Tuttle (talk) 01:58, 3 May 2010 (UTC)
 * The program exists in several versions of Basic, including Visual Basic script which runs fine here in asp as proof of concept demonstration with a limited number of variables and states. The 64k limitation is for Visual Basic v6 running anywhere unless there is a workaround. Server-side the limitation for Visual Basic Script is server time out and although a local copy runs fine it still takes too long to run even for only 5 variables in 6 states. As stated above there are other ways perhaps of doing it but all will require a larger system due to the inherent limitations of time and memory when resorting to virtual memory on a PC. What is really needed is a distributed system to handle processing requirements of a 3^9^2 matrix with 256 byte cells. 71.100.1.71 (talk) 08:31, 3 May 2010 (UTC)
 * If you want to distribute a computation, you will need to break up the work into smaller pieces anyways (unless Visual Basic has sophisticated data parallelism mechanism, but no one would implement a feature like that limits arrays to 64k). It sounds like the big problem here is that the language implementation.  I think that all programmers should be polyglots, so I think the best thing is for you to reimplement it in R (or, similarly, MATLAB or Mathematica).
 * Now, based on your numbers, it sounds like you'll be waiting a very long time for the computation to finish, even if you have dozens of fully-utilized computers at your disposal (and making them fully-utilized can be a massive engineering problem). But where are you getting gigabytes and gigabytes of input data?  If you don't have that much input data, then maybe you're experiencing an exponential blow-up in the intermediate representation, and you should definitely take a look at the algorithm, and see if a faster approach (or a fast approximation) hasn't been discovered.  Lots of research has gone into attacking NP-complete problems.  Paul (Stansifer) 14:26, 3 May 2010 (UTC)

While it may be desirable to have more programmer control over Basic statements and functions the problem with VB.NET is that it destroyed ease of programming in the process. On the other hand many of the default settings which VB.NET do not follow the conventional setting and can not be changed by the applications programmer at all or without days of time spent learning how to change the setting. The first rule I learned in computer programming class was "KISS." Apparently the authors of VB.NET were never introduced to this rule in the attempt to make VB function Like C. 71.100.1.71 (talk) 12:27, 4 May 2010 (UTC)

Looking for the name of something
If you check out this page you will see that it refers to a game in 2010, yet the name listed in the tab name (both IE and Firefox) and in the tool tip refers to 2008. I'd like to bring this to their attention, but want to refer to the terms correctly. My guess is someone copied the 2008 template to use for 2009 and 2010, but forgot to update something - I'd like to know what the "something" is called so I can ask them to fix it.-- SPhilbrick  T  16:11, 2 May 2010 (UTC)


 * It is the HTML tag. Choose "View Source" or View -> Page Source from your browser's menus and you'll see the 2008 mention right at the top.  Comet Tuttle (talk) 16:13, 2 May 2010 (UTC)
 * Thanks. Oddly, I used to view source all the time, but in my pre-FF days. I have no idea why I couldn't remember what to do, but that's what I needed - thanks.-- SPhilbrick  T  16:52, 2 May 2010 (UTC)

Internet explorer question
How do you turn on and off the automatic translation of internet pages from other languages to english?

Also, how do you switch back to the old version of the Internet Explorer? I downloaded the newest one, but its terrible... I went to the same, official, site, but I cant find the older version?

Thanks. --92.244.136.97 (talk) 16:36, 2 May 2010 (UTC)


 * I believe that you can emulate older versions of Internet Explorer via IETester, but I've never tried this.


 * Do note that there are alternatives to IE: Firefox, Opera, Safari, Chrome, K-Meleon, SeaMonkey, etc. -- Hoary (talk) 16:43, 2 May 2010 (UTC)


 * To downgrade Internet Explorer 8, please see the Microsoft Knowledgebase article [Link]
 * To translate webpages automatically, without visiting a site every time, you will need some form of plugin for your browser. One option may be the Google toolbar that supports webpage translation [Google toolbar] --CmdAltDel (talk) 16:55, 2 May 2010 (UTC)


 * Just curious which "automatic translation" you are talking about? I am unaware of any such feature available as standard in Internet Explorer.  Astronaut (talk) 18:11, 2 May 2010 (UTC)

Reinstalling Windows
My mother's computer, to put it lightly, is a mess. I want to do a clean install of Windows Vista - however, her Dell computer didn't come with a Windows or MS Office disk. My question - what's the easiest way for me to do a reinstall here and keep her OS and office software? Magog the Ogre (talk) 17:27, 2 May 2010 (UTC)


 * This is probably what you want. It will restore the computer to it's original condition, including any software like MS Office that came with the computer. Anything installed after will not be preserved and you will need to back up all important data and programs as they will be erased. 82.43.89.71 (talk) 17:35, 2 May 2010 (UTC)
 * Is there something like that for WinXP please? 92.28.253.63 (talk) 10:33, 3 May 2010 (UTC)
 * If your Dell computer has Windows XP installed, it might have a Dell recovery partition (created by Dell during manufacture/setup). Many other manufacturers use a similar technique to allow customers to "go back to factory condition", but it is not guaranteed.  If you don't have a recovery option aet up by the manufacturer, the original Windows XP installation disk that came with your PC will let you do a repair installation or reinstall Windows XP.  Astronaut (talk) 13:58, 3 May 2010 (UTC)
 * Right. Most HPs are the same way now, too.... Kingsfold (talk) 15:23, 3 May 2010 (UTC)
 * Many computers don't come with installation disks anymore. The computer prompts the user to burn one a few days after first using the computer. 82.43.89.71 (talk) 14:23, 3 May 2010 (UTC)
 * Manufacturers don't trust consumers with proper install disks any more; they all come with "restore" disks now. Riffraffselbow (talk) 06:37, 7 May 2010 (UTC)

Mayday virus?
Yesterday, I saw a flood of IPs hitting 90XX ports on my network like 9036 and 9058, mostly coming from North American cable and DSL modems. The attempts were blocked at my NAT firewall. There was no legitimate reason for the activity, so I reported as many as I could to the abuse contacts. The activity ceased around midnight. I checked the antivirus companies' websites and saw nothing specific about it. Does anyone know anything about a "mayday" virus, or was it just a fluke? PCHS-NJROTC (Messages) 19:34, 2 May 2010 (UTC)

Add-ons in Google Chrome
A lot of the add-ons available for Chrome are add-ons that were once only available for Firefox. How come in Chrome you don't have to restart the browser when installing/updating an add-on like you do with Firefox? 24.189.90.68 (talk) 20:34, 2 May 2010 (UTC)


 * I believe it has something to do with the fact that Firefox extensions run in the same process as the browser, so that you have to restart the entire process to get the add-on, however Chrome runs extensions as a seperate process, so it can be started/stopped independantly of the main browser window. -CmdAltDel (talk) 11:37, 3 May 2010 (UTC)


 * Note that this is a general case of two ways a program can work:


 * 1) Load all modules when the program is started. This can make startup take longer, and, as noted, requires a restart when any module changes, and can also require more memory, if less than all of the modules are actually needed.


 * 2) Load modules as needed. This can make startup quicker, but can also lead to a delay the first time each module is accessed (in this case, the first time the add-on is used). StuRat (talk) 14:00, 3 May 2010 (UTC)


 * A process is just an address space and some permission bits. There's no reason for process boundaries to have an effect on whether you can load/unload extensions on the fly. The difficulty with on-the-fly loading and unloading is just that a protocol for doing it has to be designed and documented and every extension has to support it. This can't be done automatically. For example, NoScript replaces Flash applets with a colored box that, when clicked, asks you if you want to load and run the applet. What should happen to these boxes when the NoScript extension is uninstalled on the fly? Only NoScript knows. The only alternative would be to unhook NoScript and then reload, reparse and rerender every page, which is basically just a minor variation of restarting the browser. When upgrading NoScript, you can't just unload the old version and then load the new one, since that might permit blocked scripts and applets to run momentarily. And many extensions wants to do special things when the browser starts up, things that they can't do when started on an already-running browser. These are solvable problems, mostly, but you have to design and implement the solution.


 * It appears that this feature has been implemented in Firefox 4.0 (?). See Extension Manager:Bootstrapped Extensions and Bug 542385. But add-ons have to be modified to support it, and few of them have been right now. -- BenRG (talk) 22:59, 5 September 2010 (UTC)

Wikipedia Editing on BlackBerry/Droid
What is the best portable app for editing on a BlackBerry or Droid? I have seen a lot of Wikipedia portable apps for viewing and searching Wikipedia but would like to know what's best for editing. Thanks. LoreMariano (talk) 21:04, 2 May 2010 (UTC)
 * Try Opera Mini. PCHS-NJROTC  (Messages) 04:20, 3 May 2010 (UTC)

MySQL "loose" collation?
Does MySQL have any collations for latin1 or utf8 in which æ = ae and ' = ′ ? Neon Merlin  21:51, 2 May 2010 (UTC)

Drive letters
There are 26 letters in the alphabet. With a:\, b:\, c:\ and d:\ already taken, does this mean if I had 26 external hard drives I couldn't connect them all at the same time to one Windows computer? Or can drives "letters" also be numbers? 82.43.89.71 (talk) 22:40, 2 May 2010 (UTC)


 * For NTFS filesystems, you have to use Volume Mount Points if you want more than 26 total drives. --Mr.98 (talk) 22:45, 2 May 2010 (UTC)


 * Do you actually have, and have a need to attach, 26 external drives? If so, my curiosity is piqued.... Kingsfold (talk) 15:22, 3 May 2010 (UTC)
 * lol, I was just curious. I currently have 8 external hard drives, but I rarely use more than 2 at a time. 82.43.89.71 (talk) 15:26, 3 May 2010 (UTC)
 * I understand the logic behind the question, though. I haven't used A or B since I quit using 3.5 or 5.25 floppy disks, but with all of my gadgets (iPod, GPS, thumb drives, external drives, camera, and virtual drives (to run CD-ROM programs without actually carrying the CDs around), I have almost all of the rest of the letters covered, although not all at the same time.... Kingsfold (talk) 16:26, 3 May 2010 (UTC)
 * ext2fsd seems to support setting 0-9 as drive letters as well. I just tried it and don't see any obvious way to get the rest of the system to access it though, so I'm not sure why it's there. --Scgtrp (talk) 23:07, 3 May 2010 (UTC)
 * For the record, I currently have 14 lettered drives and partitions currently mounted.
 * 3 hard drives, amounting to a total of 6 partitions and approximately 2.1 TiB. 2 disk drives. 2 virtual disk drives. 4 seperate drives letters, one for each of the reader slots on my multi-card reader. Feels good. Riffraffselbow (talk) 06:35, 7 May 2010 (UTC)