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April 29

IRC Aggregator Bot?

Is anyone aware of such a thing? Basically what I would like is to be able to park a bot in 5 IRC rooms plus it's own room (##BOT or something) and have it repeat everything said in the other 5 IRC rooms? ^Avicenna_sis @ 05:51, 29 April 2010 (UTC)

I don't know of one offhand, but the IRC protocol is pretty simple, so depending on how much programming you want to do, you could make one yourself. There are lots of IRC libraries for easy use too. Shadowjams (talk) 05:40, 2 May 2010 (UTC)

Wikipedia use ontologies for manage the knowledge and the relations between them?

Wikipedia use ontologies (as an informatic concept) for manage the knowledge and the relations between concepts? with some special software for include intelligence to the web site? —Preceding unsigned comment added by 157.159.40.82 (talk) 09:52, 29 April 2010 (UTC)

The above question was asked by 157.159.40.82 (talk). 24.189.90.68 (talk) 10:05, 29 April 2010 (UTC)

I'm not sure if I understand the question, but if you are asking, "could the links made between articles and concepts on Wikipedia be made, along with specialized software, into some kind of rich semantic web for an A.I. program?" the answer is, "maybe." I don't see any a priori reason why that couldn't be the case. But writing an A.I. program that could take advantage of such things is non-trivial. There are a number of smaller scripts that mine Wikipedia for semantic data, but Wikipedia's data is not very uniform in most cases, which makes anything but very trivial things hard to do. --Mr.98 (talk) 12:50, 29 April 2010 (UTC)

Firefox SSL warning

Is there a way to disable the warning about a wrong SSL certificate for certain sites? I'm accessing a few servers via SSH's port forwarding, so I'm always using https://127.0.0.1 to access the servers, with the real IP being hidden by the SSH connection. In its default configuration, Firefox allows me to whitelist a certain certificate for a certain IP, it seems, but if the certificate changes (because the server behind the SSH connection changes), it nags me again. Is there an about:config hack that allows me to whitelist 127.0.0.1 or 192.168.0.0/16, so that wrong certificates for this IP or IP range are never reported (or at least not with such an endless array of click-throughs, a simple "Are you sure?" would be acceptable)? As I'm using the same Firefox for regular browsing, I would prefer it if I don't have to disable the warning mechanism entirely. -- 78.43.60.58 (talk) 10:14, 29 April 2010 (UTC)

Why are the certificates changing? If you're making these certificates yourself, make a CA and install it in your Firefox as a trusted root, and sign your certificates with it, instead of having them self-sign if that's what you're doing now. 69.228.170.24 (talk) 23:38, 29 April 2010 (UTC)

They are changing because they're at different locations, and I'm not in the position to install different certificates on them. So I really need to disable the feature in Firefox. -- 78.43.60.58 (talk) 09:11, 30 April 2010 (UTC)

Can't you whitelist multiple certificates for the same IP in firefox? I suppose you could set up a proxy server on your local client that gives Firefox a certificate it likes, but it sounds like you're really trying to stop checking the certificates, in which case why even use ssl? Why are you tunnelling ssl through ssh anyway? If you trust the machines at the other end and you trust the ssh fingerprints and the security of ssh, just run http through ssh. 69.228.170.24 (talk) 05:58, 1 May 2010 (UTC)

No, I can't whitelist multiple certificates for the same IP (at least there is no obvious way to do so), otherwise I wouldn't be asking for help here. As soon as I tell it to save the second certificate for 127.0.0.1, it forgets about the first. If you happen to know how to change that, please do share.

Again, I have no control over the remote endpoints - they speak HTTPS and only HTTPS, so I have to deal with that. I need to get Firefox to comply, not the remote endpoint. -- 78.43.60.58 (talk) 16:00, 3 May 2010 (UTC)

The workaround I'd recommend is using ssh SOCKS forwarding (the -D switch) instead, and telling Firefox to use 127.0.0.1 as a SOCKS proxy. You can even tell FF to only use the proxy for some specific sites by writing your own proxy auto-config script. —Ilmari Karonen (talk) 12:24, 4 May 2010 (UTC)

My pen drive .

My pen drive don't allow to format .How can I format it. —Preceding unsigned comment added by 192.248.87.1 (talk) 16:11, 29 April 2010 (UTC)

Some pen drives have a little switch on the side which prevents the computer modifying data on the drive unless it's set in the "write" mode. Or the drive might have just failed, in which case there is nothing you can do to fix it and you would need to get a new one. .tkqj (talk) 16:21, 29 April 2010 (UTC)

HP has a utility that might work: http://files.extremeoverclocking.com/file.php?f=197 The brand and model of your drive might let use help you more. ---— Gadget850 (Ed) ^talk 00:56, 30 April 2010 (UTC)

jit compilers

the machine language code blocks produced by the jit compilers are deleted when the application is closed? t.i.a. --87.5.125.159 (talk) 20:11, 29 April 2010 (UTC)

Yes. Memory space is allocated and code is emitted into that space; when the application closes the space is recovered and the code destroyed. I can't think of a circumstance where that wouldn't apply - I've never heard of emitting code into shared memory, and mobile code like JRMI is transmitted as an intermediate code like java bytecode. -- Finlay McWalter • Talk 20:26, 29 April 2010 (UTC)

I would hope that the JITted code is deleted when the application is closed, but, of course, there might be some badly-written system that keeps the code around in memory. Comet Tuttle (talk) 20:27, 29 April 2010 (UTC)

It really wouldn't be a JIT compiler if the code persisted. It would just be a regular compiler, like GCJ, that creates machine-code. Nimur (talk) 03:35, 30 April 2010 (UTC)

I thought that the .NET Framework caches its machine code in the Native Image Cache and the GAC inside the C:\WINDOWS\assembly folder. Otherwise, a .NET application would be slow to start up every time. When the native code is cached, it is only slow to start up the first time. The first time it starts, I think it compiles the bytecode JIT into native code and then caches it. The view of the assembly folder inside Windows Explorer is not very accurate, though. If you plan on taking a look to see what I mean, you should use the command prompt.--Best Dog Ever (talk) 07:18, 30 April 2010 (UTC)

Outlook / Outlook Express / Windows Mail / Windows Live Mail

Where do these programs store user and server names (POP, IMAP, SMTP)? The reason I'm asking is that I'd like to prepare a script that pulls the account info (sans password) from the file/registry, so that it can be fed into an installer for an alternate mail client like Thunderbird. -- 78.43.60.58 (talk) 21:11, 29 April 2010 (UTC)

For Outlook Express see here. -- Finlay McWalter • Talk 21:20, 29 April 2010 (UTC)

For Windows Mail see here. -- Finlay McWalter • Talk 21:26, 29 April 2010 (UTC)

Rough info about Outlook 2003 is here. -- Finlay McWalter • Talk 21:31, 29 April 2010 (UTC)

April 30

How do I connect my PC to both my monitor and TV: particularly with a splitter?

Like many people I have a desktop, including CPI and monitor, running on Windows XP.
I also have a television: specifically a Samsung flat screen.
My CPI seems to have only one VGA port, though I have a splitter as well.
When I connect both TV and monitor to the splitter, the monitor darkens a little and the TV says “PC” and “Mode Not Supported”.
Even when I just plug directly into the TV–-without the splitter--I get the same problem (“PC” and “Mode Not Supported”).
How can I get video on both TV and monitor, via splitter?
Thanks
76.68.23.9 (talk) 00:49, 30 April 2010 (UTC)

Sounds like your splitter goes from one VGA port to two. It appears that connecting to video devices in that manner is loading the VGA signals to where they won't drive either device. You need another video card in your PC or one that has two outputs. ---— Gadget850 (Ed) ^talk 00:59, 30 April 2010 (UTC)

So it would seem. The thing is, as I'm typing this response, the monitor works decently well. Also, when one boots it all up and sees things like the cursor in the black background, the Windows logo on the black background, etc, for a minute or so, it also shows up on the TV as well, then it reverts (on the TV only) to the "Mode Not Supported" again.76.68.23.9 (talk) 01:15, 30 April 2010 (UTC)

I seemed to have had some progress here.76.68.23.9 (talk) 02:06, 30 April 2010 (UTC)

Since your TV doesn't display anything when you hook it up directly, we can rule out the splitter cable as the problem. Your resolution is probably set to something higher than the maximum resolution your TV can display, which is probably either 720p or 1080p. Try setting your display resolution to 640x480 or 800x600, then shutting down the computer, then plugging it into the TV directly, then turning on the computer. The TV will probably display everything fine. Then play with the display resolution until it's the maximum your TV will display. Then try the splitter cable contraption. Comet Tuttle (talk) 03:07, 30 April 2010 (UTC)

What is a CPI in this context - presumably not Consumer Price Index?

Anyway, I sometimes use my flat screen TV as a monitor and connect using a HDMI cable for 1920x1080 resolution. The reason for my choosing that connection is that the TV's PC/VGA port will only support up to 1366x768 resolution, although the PC is capable of outputting more through VGA. Astronaut (talk) 16:20, 30 April 2010 (UTC)

CPI is most likely a typo or incorrectly remembered spelling for CPU Nil Einne (talk) 10:08, 1 May 2010 (UTC)

Shallow Depth of Field - optimum focal length

This question is being answered on the Miscellaneous Reference desk, Here --220.101.28.25 (talk) 08:52, 30 April 2010 (UTC)

Using Janusvm on Mac OS

How do you use Janusvm (http://www.janusvm.com/) on a Mac notebook or other system running MacOS? There is a lot of information explaining how to set up on Windows (using VmWare), but I could not see any information or HOWTOs on setting up on a Mac. JanusVM launches without any problems using VMWare Fusion, but I'm not able to get the VPN connection to work. Upon launch, there is a message saying that the Tor directory was being renewed but this does not seem to complete even over several hours. Many thanks in advance! —Preceding unsigned comment added by Alsopen (talk • contribs) 08:37, 30 April 2010 (UTC)

It appears that you need Tor to be installed and functional on the Mac. Have you installed Tor, per these instructions for Mac ? Nimur (talk) 15:54, 30 April 2010 (UTC)

Should firefox have 5 vesions of Java Console installed

The add-ons page for my firefox lists 5 versions of Java Console. Is it supposed to be that way? Should I uninstall the older versions? ike9898 (talk) 13:41, 30 April 2010 (UTC)

Firefox is merely reporting that there are multiple versions of Java installed on your machine (probably by external software). It is not a problem to have multiple Java installations, but is also usually unnecessary, because most (new) Java versions are completely back-compatible. However, other software outside of Firefox may have stringent JVM requirements or hard-code a required Java version/location. You should consider why the various versions were installed - determine which software depends on them, and whether all those software can switch to using a single Java version. Firefox does not need Java for anything, so you can safely remove as many as you like, leaving the most recent one intact. Nimur (talk) 15:59, 30 April 2010 (UTC)

schedule web crawler

I need a web crawler that can be scheduled to downloaded a site every 2 hours. I've tried using windows task scheduler for web crawlers I know of, namely HTTrack, but all it does it open the program and I can't find a way to make it actually start downloading automatically. Does anyone here know of a (preferably free/open source) web crawler that runs on Windows and can be scheduled? Thanks for your help 82.43.89.71 (talk) 16:14, 30 April 2010 (UTC)

wget should do it nicely (you may have to wrap it in a script). The wget article lists a number of versions that run on Windows. -- Finlay McWalter • Talk 16:17, 30 April 2010 (UTC)

Google "httrack command line" for command-line arguments, so HTTrack doesn't merely open. Comet Tuttle (talk) 17:29, 30 April 2010 (UTC)

TightVNC, Ubuntu, and the Shift key

I've just set up an Ubuntu machine with VNC; I would like to log into it with my Windows XP machine on the same network. I follow the steps here, with PuTTY and TightVNC running on my Windows machine, to log in. Everything seems to work great as I use TightVNC to control my Ubuntu machine's desktop; except that the Shift keys do not seem to work. Typing Shift-K into a terminal window just produces a lowercase "k". However, if I hold down the "k" key in a terminal window so that autorepeat starts, and then I press either Shift key, uppercase "K"s are produced for as long as I hold the Shift key. Holding the Shift key first does not produce an uppercase character. Any hints? Not being able to type * or _ or " is driving me nuts. Comet Tuttle (talk) 23:58, 30 April 2010 (UTC)

May 1

Flash player in JavaScript?

In light of the iPhone's restriction of Flash, I was wondering if it would be possible to port an open-source Flash player, like Gnash, to JavaScript, which can then be run on the iPhone as well as other devices that have a browser, without installing a separate plugin (which may not be available on some platforms, or may be inconvenient to install). You could, say, have a "Flash-to-JavaScript gateway" website which acts as a proxy for other sites, but interprets and translates the embedded Flash applets into JavaScript instructions. It may not be the most efficient of course, but it might be a way to circumvent restrictions when there is no other way. What do you think? --Spoon! (talk) 06:14, 1 May 2010 (UTC)

Something like that already exists, it's called Gordon. It's definitely not a comprehensive Flash run time but the demos are promising. --antilived^{T | C | G} 06:38, 1 May 2010 (UTC)

What is required is full HTML5 support. Without that, you cannot perform all the common functions provided by Flash. When full HTMl5 support is provided by the web browser, you will be able to load SVG images, resize, rotate, and move them. You will be able to alter opacity, brightness, and contrast. So, graphically, you will be able to mimic Flash. It will be done with HTML5, CSS, and JavaScript. -- kainaw™ 12:01, 1 May 2010 (UTC)

Data packets

What would data packets be equivalent to in MB or GB? What are they measured in? Why are they used to measure data being sent/received rather than just GB, MB, or Bytes? Chevymontecarlo. 14:36, 1 May 2010 (UTC)

A data packet could be any size. It depends on the definition of the data packet. Depending on what kind of speed you are measuring, you may be interested in actual megabytes/second or you may be interested in packets/second. They give two very different results. -- kainaw™ 14:39, 1 May 2010 (UTC)

Packet (information technology) is our article. Comet Tuttle (talk) 14:56, 1 May 2010 (UTC)

When sending a large amount of data on Ethernet the packet size is around 1500 bytes, so 666 packets in a megabyte and 666666 packets in a gigabyte. Graeme Bartlett (talk) 22:36, 1 May 2010 (UTC)

Fonts

Is it possible to make a custom font display on web pages where the viewer doesn't have the font installed? 82.43.89.71 (talk) 14:59, 1 May 2010 (UTC)

Yes, many methods use javascript. Two options may be:

Typeface which allows you to load fonts into a webpage so that a user then can read them or Fontjazz which renders the text as an image which the user then sees -- CmdAltDel (talk) 15:09, 1 May 2010 (UTC)

The feature that you're looking for is called @font-face. It's pretty new to CSS, and only recent browsers support it (it does, of course, fall back to normal web typefaces when the browser doesn't support it). See Web typography, and http://nicewebtype.com. Paul (Stansifer) 15:15, 1 May 2010 (UTC)

(even though @font-face doesn't work for all users, it has the advantage that the result that it produces is bona fide text for everyone, and you don't have to worry about the complexities of making the result properly usable, resizeable, color-matched, and everything. As time passes, and users upgrade their browsers, more and more will see the custom font you want. Paul (Stansifer) 13:29, 3 May 2010 (UTC))

When I want to display a custom font, I just type out the text in an image-editing program like Photoshop or Illustrator and then save the text as an image. This will enable the largest number of viewers to see the text as it was meant to be seen. However, to ensure that people using screen readers are still aware of the text, be sure to add an alt attribute to the image (e.g., <img alt="Main section title" src="img.png">.--Best Dog Ever (talk) 02:48, 2 May 2010 (UTC)

Extra heavy period

Speaking of custom fonts, is there one with extra large/bold commas and/or periods ? I ask because I can't tell them apart on my screen without magnifying the text. And, if there is one, how can I use it as my default font in Wikipedia ? StuRat (talk) 17:18, 1 May 2010 (UTC)

I don't have a real answer for you, but I'd check out people who will do all kinds of stuff for $5. For a small fee, you could probably find someone who would modify a few of the standard font files on your system -- problem solved! DaHorsesMouth (talk) 20:42, 1 May 2010 (UTC)

What font do you currently use? Maybe you can customize your font using a font editor and replace the regular period and comma glyphs with their bold variants. --98.114.146.58 (talk) 08:53, 2 May 2010 (UTC)

I'm not sure what font I currently use. How can I find out for Firefox 2.0.0.20 ? StuRat (talk) 14:04, 3 May 2010 (UTC)

Not sure. Try the Content tab under Tools>Options. Once you find out what your default font is, try changing it to something else and see if the period and comma glyphs look more different in the new font. If that doesn't work, you can try creating a customized font using a font editor, such as Fontforge. --98.114.146.58 (talk) 02:50, 4 May 2010 (UTC)

Thanks. It lists my current font as Times New Roman, 16 point. None of the other fonts available seems to have commas or periods which are proportionally any larger larger. StuRat (talk) 17:59, 6 May 2010 (UTC)

Looking for Cloud Computing Reference in a University environment

I am trying to design from scratch an Infrastructure with application saervices on the cloud for a new university. This includes the server, intra-network, the HR system with its DB , HR system , email as well as the Student information System (banner like). I am looking for a university that have implemented or is planning to implement such system. —Preceding unsigned comment added by Shaltout51 (talk • contribs) 20:09, 1 May 2010 (UTC)

Project Athena, from MIT, has been the de-facto standard for large (enterprise-scale) university network infrastructure, servers, and clients. Understandably, this infrastructure is very complex, and consists of many variants and sub-elements. Unifying the compute infrastructure is one thing; implementing an HR system from scratch is an endeavor unto itself. Nimur (talk) 20:13, 1 May 2010 (UTC)

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? NeonMerlin 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? NeonMerlin 05:18, 2 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 ??.wikipedia.org that all run the same software (and the thousands of unaffiliated MediaWiki installations all over the web), or the totally different applications between google.com and mail.google.com. 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)

PHP question

Resolved

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.--SPhilbrickT 16:11, 2 May 2010 (UTC)

It is the <title> 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.--SPhilbrickT 16:52, 2 May 2010 (UTC)

Awakening SCIM

I have three laptops running (K)ubuntu, each with CapsLock and Ctrl reversed, and each with SCIM and Anthy. I only bought the newest of these ("13z") a couple of weeks ago and for one reason or another hardly it (with Ubuntu 9.10) rather little until yesterday. But with SCIM and Anthy installed on it, toggling Ctrl-space (or, according to the keytop, CapsLock-space) did switch between direct input and Japanese.

A few days ago I noticed that Ctrl-space had stopped working. In effect, Japanese seemed to have disappeared. That was irritating, and today I was going to do something about it when I noticed that Ubuntu 10.04 was already out, and so instead installed that first.

"Ubuntu Software Center" in 13z (now running 10.04) tells me that yes, SCIM, scim-anthy and libanthy0 are all installed. The little keyboard icon of SCIM is at the top right of the screen of 13z. Right-clicking it and selecting "SCIM Setup" shows a setup that -- aside from the addition of something called "PRIME" -- is exactly the same as the setup in an older laptop ("Mini 10") running Ubuntu 08.04. (I don't know what more than half of the stuff means, but comparing the two screens I see it's identical.)

In Mini 10, Ctrl-space virtually always does what I want it to do. On occasion it doesn't and I infer that must have accidentally hit some key combination that knocked it sideways from Japanese: I then right-click a blue and purple "SCIM" icon and tell it that it's Japanese (and not, say, input by ) that I want to be switched on and off. In 13z, I see no blue and purple "SCIM" icon. All I see is the keyboard icon. This has other right-click options, none of which appears to do anything: "Reload Configuration", "Stick Windows" (stick which windows where?), "Hide Toolbar" (hide which toolbar?), and (for a touch of comedy) "Help" (which offers no help whatever).

Uh . . . what am I overlooking? -- Hoary (talk) 16:30, 2 May 2010 (UTC) ..... slightly reworded Hoary (talk) 00:22, 3 May 2010 (UTC), 04:59, 3 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)

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)

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 ' = ′ ? NeonMerlin 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)

May 3

networking essentials

what is networking essentials and what is really involved in networking essentials? —Preceding unsigned comment added by Michaelchawiya (talk • contribs) 09:14, 3 May 2010 (UTC)

This sounds like a homework question. Please see {{dyoh}} 82.43.89.71 (talk) 10:31, 3 May 2010 (UTC)

PHP question

Would it be possible to use php to convert a folder full of htm files to mhtml? 82.43.89.71 (talk) 15:22, 3 May 2010 (UTC)

Yes, but it might be difficult to do from scratch. PEAR, which you can get from the official PHP distribution site, will greatly assist you with this task. I think there's a Base-64 PEAR utility, and there is Mail_Mime that can easily create and work with MIME encoding and decoding. Nimur (talk) 16:24, 3 May 2010 (UTC)

Perl: Manipulating an XML file

I have an XML file that roughly looks like this:

<?xml version="1.0"?>
<main>
  <something>
    <somemore>here</somemore>
    <disabled />
    <name>SomeThing</name>
  </something>
  <somethingelse>
    <somethingcompletely>different</somethingcompletely>
    <name>SomeThingElse</name>
  </somethingelse>
</main>

How would I go about if I wanted to remove the tag

<disabled />

in the part where the value of "Name" is "SomeThing", and add it in the part where the value of "Name" is "SomeThingElse"?

I think I could come up with a RegEx for that, but my gut feeling is that I shouldn't use RegExes in an XML document. However, I've never manipulated XML files before, so I'm not sure what the beginner-friendly options are (there's a whole manure-load of XML-related modules on CPAN). Ideally, I'd like to use a module that is part of the standard Ubuntu Hardy Heron release, or at least has a .deb package in a standard repository. -- 78.43.60.58 (talk) 16:50, 3 May 2010 (UTC)

I can't help you with Perl, but doing it in Python (with the BeautifulSoup XML processor) is straightforward:

#!/usr/bin/python
from BeautifulSoup import BeautifulSoup

soup = BeautifulSoup("""
<?xml version="1.0"?>
<main>
  <something>
    <somemore>here</somemore>
    <disabled />
    <name>SomeThing</name>
  </something>
  <somethingelse>
    <somethingcompletely>different</somethingcompletely>
    <name>SomeThingElse</name>
  </somethingelse>
</main>
""")

for x in soup('disabled'): x.replaceWith('')
print soup

I'm sure Perl will have any number of equivalent libraries. -- Finlay McWalter • Talk 18:05, 3 May 2010 (UTC)

Laptop freezing

I have a Dell Inspiron I bought last year. I forgot which model # but now when I surf the internet, it freezes after 15 min. no matter where I am. I do have McAfee Total Protection and I almost run the Spybot daily. What can I do to fix this? --Reticuli88 (talk) 19:39, 3 May 2010 (UTC)

Some questions: What version of Windows are you running? What browser do you use? Do you use wired or wireless networking? Have you tried using a different Web browser instead? Does the computer freeze after 15 minutes even if you don't have a Web browser open? Comet Tuttle (talk) 20:42, 3 May 2010 (UTC)

The laptop could be overheating. Press F2 during startup to access BIOS and check the temperature of the parts inside your computer (viz. the CPU). Also check the event log for errors: Go to Start --> Run... and type eventvwr.msc. Also check the device manager (right-click on My Computer --> Manage --> Device Manager) for driver issues.--Best Dog Ever (talk) 21:28, 3 May 2010 (UTC)

Windows Vista, Mozilla, wireless, no I haven't, I haven't tried that yet --Reticuli88 (talk) 00:35, 4 May 2010 (UTC)

Best Dog Ever: What do I do after I access BIOS and check the temp? --Reticuli88 (talk) 00:36, 4 May 2010 (UTC)

Write down the temperatures and Google them. Sorry, but each CPU and motherboard has a different maximum temperature, so it really depends on the make and model of the CPU in your laptop. Some BIOS versions don't show the temperatures, though.--Best Dog Ever (talk) 01:44, 4 May 2010 (UTC)

I get "Error Code 0142. Error code 2000-0142. Hard Drive 0 - self test unsuccessful status: 79 --24.218.203.121 (talk) 01:19, 4 May 2010 (UTC)

It could be a failing hard drive. Did you buy the laptop when it was new or used? A model number would help, too.--Best Dog Ever (talk) 01:44, 4 May 2010 (UTC)

Yes, a new hard disk is the only thing that seems worth trying at this point. Comet Tuttle (talk) 05:10, 4 May 2010 (UTC)

Insprion 1545 --Reticuli88 (talk) 12:18, 4 May 2010 (UTC)

Converting Wikipedia articles to plain text en masse

How can a whole history's worth of article revisions turned into plain text and have the wiki markup deleted? MarkkuP (talk) 21:32, 3 May 2010 (UTC)

After obtaining the revisions in the manner you prefer, like Special:Export or a database dump, you can use one of the alternative parsers to turn it into a format of your choice. decltype (talk) 10:40, 4 May 2010 (UTC)

Thank you. MarkkuP (talk) 18:49, 4 May 2010 (UTC)

Blu-ray playback on PC

My computer can play Blu-ray, but it has a (noticable) skip. Can anyone tell me what I'm doing wrong, so that I may try to rectify the issue? Specs Intel Core 2 Duo E4500 (2.2 GHz, 2MB L2) 6GB DDR2 800 500GB HDD, ~70% full Radeon HD3650 (1GB DDR2) Gigabyte Mobo Internal BD-ROM (I think it's 4X) Thanks. If I left something out, ask. Mxvxnyxvxn (talk) 21:36, 3 May 2010 (UTC)

What software are you using to play it? 82.43.89.71 (talk) 21:39, 3 May 2010 (UTC)

The included PowerDVD (Came with the drive.) Mxvxnyxvxn (talk) 05:10, 4 May 2010 (UTC)

That PC spec can certainly handle bluray. I managed to get bluray playback working perfectly with the free player Media Player Classic (you will have to open the VOB? files individually though). This was years ago in the early days of bluray however; I'm sure bluray playback on PCs has come a long way since then. I remember I had to install Nvidia Pure Video so I'm not sure if there's an equivalent for ATI. You can also investigate the Matroska Splitter drivers for HD playback. I stopped caring when I bought a PS3 but that's cheating... Sandman30s (talk) 19:53, 4 May 2010 (UTC)

Is your virus scanner checking out the contents of the disk? Also have you got the hardware acceleration turned on? Is you computer doing anything else at the same time? Graeme Bartlett (talk) 22:13, 4 May 2010 (UTC)

May 4

Wikipedia date being updated

Every day the English Wikipedia Main Page presents a different FA, a different FP, different On this day and Did you know sections. So I can see the new content of the page, it's enough to click on the reload button of my browser exactly at 00:00:00 UTC. However, reloading doesn't work so momentarily for some other Wikipedias, especially for some smaller ones. Hitting Ctrl+F5 sometimes doesn't work either; I therefore have to purge the Main Pages to be able to view the content corresponding to the current date. I'm just curious - why so? If that matters, the browser I usually use is Mozilla Firefox. Thanks. --Магьосник (talk) 00:22, 4 May 2010 (UTC)

My guess would be because they're small and thus don't have as much people working on them, let alone the Main Page. —Jeremy ^{(v^_^v Dittobori)} 00:36, 4 May 2010 (UTC)

This has been done to change automatically, hasn't it? Is the automatical updating of something like this: {{Wikipedia:Today's featured article/{{CURRENTMONTHNAME}} {{CURRENTDAY}}, {{CURRENTYEAR}}}} affected by the number of people working? I will try to rephrase what I'm wondering about. If I visit the English WP Main Page for the first time today, say, at noon, then it will always show the current date. If I do the same with, say, the Icelandic WP, it will often show the previous date. And I'll be able to correct this just in a second by purging the page. That seemed odd to me, and I decided to ask about it here. --Магьосник (talk) 00:56, 4 May 2010 (UTC)

I don't really know, but I wouldn't be surprised if there was a bot that purged the Main Page a few seconds after midnight UTC. It would take nothing but a trivial one-line cron entry running on the toolserver. (Hmm, OK, maybe a few more lines, since it'd have to either log in or deal with the confirmation button that action=purge gives to anon users.) It would take me all of fifteen minutes to set up, so it seems quite likely that someone has else already done it. Presumably whoever it was wasn't Icelandic, though. —Ilmari Karonen (talk) 12:14, 4 May 2010 (UTC)

How does RAID1 behave in the face of a single disk corruption?

After having a hard drive fail on me, I have considered using a RAID1 setup for my replacement, but there is one scenario that bothers me. RAID1 can obviously save your data if one drive is completely broken (i.e.: can't be read), but what happens if the drive still operates while returning incorrect data? What if the data on one of the drives becomes corrupt? How would the RAID1 controller/software know which drive is returning the correct data? If it can't tell this, what happens? Will there be a risk of the corrupted data propagating? --35.11.183.86 (talk) 02:37, 4 May 2010 (UTC)

Firstly, while not really answering the question, RAID 1 is not a replacement for good backup practices. There are plenty of cases when RAID 1 won't protect against data loss, e.g. file system corruption, accidential or malicious deletion (including malware), simultaneous failure of both hard drives (e.g. due to catastrophic power supply failure), or near enough (e.g. if they are from the same batch they can sometimes fail at around the same time and if you are in a server or other situation where you can't afford downtime so keep running until you get a replacement for the broken disk, such a situation is really one of key reasons for RAID), some sorts of controller failure... If you are thinking of using RAID 1 as a substitute for good backup practices, I strongly recommend against it. In terms of your question, if the drive knows the data is corrupt, then that shouldn't be a problem. Even if it doesn't you may be able to manually work out which drive is corrupt, by comparing the differences and trying to work out which one is correct (if it's file system information, or a file you have a checksum of, or a file with builtin checksum verification like an archive it should be easy). In terms of how the controller handles it, I don't really know much about RAID 1 but if I'm not mistaken you can set it so it does alternate read requests to speed up reads. If you do this then clearly the controller/software is NOT going to know the data being returned is different, since it's not reading the same data twice. I presume you can set it up with some hardware/software so it doesn't do this and instead reads both and then compares, in such a case, I expect you receive some sort of error message about inconsistent data and you should then shut down and backup as much as you can of both disks and then work out what the problem is. But for good measure, let me repeat again that using RAID 1 doesn't mean you should stop backuping up data (if you aren't you may want to consider starting and if you can't afford to do both, it's probably better to backup rather then set up a RAID 1 array). Nil Einne (talk) 04:35, 4 May 2010 (UTC)

From personal experience: If two disks are run in RAID1 mode and have identical directories and files, yet different file contents for the same file (because of an error on the disk or because one of the disks was accidentally mounted as an ordinary, non-RAID disk, and then re-joined into the RAID), you'll end up with garbage, as the controller/driver picks one chunk from disk 1 and the other from disk 2. Obviously, with two disks, there is no room for checksumming. If that's what you want, you will have to use a RAID5, which requires at least 3 disks, one of them keeping the checksum. -- 78.43.60.58 (talk) 13:23, 4 May 2010 (UTC)

I don't see how RAID5 improves matters. In either RAID1 or RAID5, the disks aren't usually checked for consistency for performance reasons, and there would be no way to automatically tell which disk was at fault if you did find an inconsistency. You need at least three parity blocks to correct one error, and RAID5 only has one. -- BenRG (talk) 17:43, 4 May 2010 (UTC)

High-end storage arrays (the kind whose cost is on the order of my salary) often provide a background "parity scrub" feature that periodically or continuously scans the disks checking for parity errors. But you're right, "RAID5 does not provide a means to locate or correct an error detected in the above manner." -- Coneslayer (talk) 19:46, 4 May 2010 (UTC)

Why is steam download so hard to find?

I realize this may be a subjective question, but I recently was trying to download Valve's Steam application to my new Windows 7 partition. In the past the only thing you had to to do was go to Steam's web site and there was a big download icon right in front of your face (https://support.steampowered.com/kb_article.php?p_faqid=144).

Now, whenever you go their web site there is no download link on the front page. It took me a few minutes of searching to find out you have to click on the About link on their front page to get the link to download the file.

Why would they make this so obtuse? Who is going to click on the About link on a web site? Usually that's where you find out about a company's philosophy, goals, etc.; I usually could care less. Why wouldn't they want people downloading their application the second they went to their web site? I don't understand the thinking behind this. —Preceding unsigned comment added by 70.245.111.56 (talk) 06:18, 4 May 2010 (UTC)

Yeah, no kidding. I've never understood why it was hard to find before (it was not a very big or noticeable button), and now it's even worse! Man. Indeterminate (talk) 09:44, 4 May 2010 (UTC)

I think you mean that you couldn't care less. If you could care less, then you care at least a little bit. I know, this isn't the language desk... Dismas|^(talk) 10:12, 4 May 2010 (UTC)

Just click "About" on the menu, there's a large green "Install Steam Now" link on that page. ZX81 ^talk 10:18, 4 May 2010 (UTC)

Well they do show you a big download link after you've purchased a game... Maybe they figured that you probably don't need Steam if you don't have any Steam games? --antilived^{T | C | G} 10:26, 4 May 2010 (UTC)

FORTRAN Programming (Lahey Compiler)

I am trying to run one old fortran program (1980's). I compiled it using Lahey Compiler and i removed all errors and warnings. It is not running properly, if i give some print or write commands at some particular locations in some subroutines, it starts running. I am not able to understand without making any change in the code how is it running just due to some print or write commands and the results are still some what away from expected. —Preceding unsigned comment added by 203.199.205.25 (talk) 07:16, 4 May 2010 (UTC)

It is safe to say that there is no way we can possibly answer this question in its present form. Consider reading our guide on how to ask a software question. If you inherited legacy source-code, and then modified it, and now it doesn't work, there literally infinite numbers of possibilities for what is going wrong. Consider reading our debugging article to gain some insights into the methodical process of narrowing down what is broken. If you can provide a simple, short code-fragment that demonstrates the problem, we can start helping you. Additionally, the methodical process of identifying which portion of your code is actually the broken part will also help you figure the problem out. Try to identify the last portion of the code which is running properly. By definition, the bug immediately follows that code section. Nimur (talk) 10:59, 4 May 2010 (UTC)

Actually, I've encountered exactly this type of bug before, where adding a print changes whether the program runs. This is usually the sign of a memory leak, as when an array or character string is filled beyond the declared length, and thus happily overwrites whatever follows in memory. This may or may not cause an error, depending on what follows in memory, and adding print statements can affect that. One way to debug this is to temporarily declare each array or string to be huge (obviously within memory limits), one at a time, and see if that fixes the problem. When you find the problem array or string, track it through the program to try to find the place where it overflows. Note that you often don't get an error right where the overflow occurs, but later, when the program tries to use whatever was in that chunk of memory. This makes such bugs difficult to track down, as does their intermittent nature. StuRat (talk) 18:41, 4 May 2010 (UTC)

I'm not familiar with the Lahey Compiler, but most compiler have a variety of switches to turn on stricter standards compliance, array bounds checking, and produce additional listings of data disposition, array usage, machine code, etc. Failing that, there might be various debug options to allow you to step through the program ones line or instruction at a time and display the status of all kind s of things as you go. Astronaut (talk) 19:03, 4 May 2010 (UTC)

There's a technique I sometimes use to track down a bug. Here's a chunk of code with an obvious bug:

PROGRAM WB
CHARACTER*10  SUSPECT
DO I = 1,99999
  SUSPECT(I:I) = "X"
ENDDO
END

But let's imagine it wasn't so obvious (perhaps the value of I is determined by some complex formula, rather than just incrementing in a loop). I add a junk string before and after the SUSPECT string, and check for when either gets overwritten. (Depending on the compiler, either junk string may follow the SUSPECT array in memory, possibly with a short gap in between.)

PROGRAM WB
      character*10 junk1
CHARACTER*10  SUSPECT
      character*10 junk2
      junk1   = " " ! Blank out both strings.
      junk2   = " "
DO I = 1,99999
  SUSPECT(I:I) = "X"
        if ((junk1 .ne. " ") .or. (junk2 .ne. " ")) then
          print *,"Memory overflow detected at I = ",I
          print *,"junk1 = >",junk1,"<"
          print *,"junk2 = >",junk2,"<"
          stop
        endif
ENDDO
END

This produced the following output on my PC:

Memory overflow detected at I =  129
junk1 = >*         <
junk2 = >          <

So, apparently my compiler allocated 128 bytes to the SUSPECT array, then allocated junk1 right after that. StuRat (talk) 19:32, 4 May 2010 (UTC)

android browsers

I've put two android browsers on my android phone. The one is the standard android browser that comes w/ the phone. I also installed Skyfire. I want one set of bookmarks on the one browser, lets say the 'work' bookmarks, and a different set on the other browser, let's say the 'home' bookmarks. But they both seem to know what the other does, and bookmark and remember on both browsers what is accessed on the other. How do I separate them so that they operate discreetly (so to say). —Preceding unsigned comment added by 80.101.134.43 (talk) 09:13, 4 May 2010 (UTC)

Phishing - what is going on here?

Hi. I recently had a virus on my PC which had performed some kind of browser hijack. Once I cleaned the virus IE and Opera would no longer connect to the internet and gave a proxy related error. Of course, that was because the virus had installed an executable that was acting as a local proxy, and when it was removed the proxy was no longer available. So, I went into IE and Opera and set the connection settings back to use no proxy - which fixed the problem. During this time Firefox seemed unaffected and does not seem to have been configured to point to a proxy. I have run several complete scans (including heuristics) using F-Secure and the machine seems clean. Hwoever, this morning when I went to log into my online banking using Firefox, I got a very suspicious login screen:

http://www.flickr.com/photos/49893252@N04/4577352131/sizes/o/

which differs substantially from the usual login screen:

http://www.flickr.com/photos/49893252@N04/4577984292/sizes/o/

As you can see, the suspicious screen asks for all kinds of card details that an online banking screen would never ask for. I called the bank and they confirmed that the screen is fake, but were not able to explain what was going on.

Looking a bit deeper, it seems that the site itself is valid and has a valid certificate:

http://www.flickr.com/photos/49893252@N04/4577984360/sizes/o/

which appears to match the certificate for the site displayed by Opera:

http://www.flickr.com/photos/49893252@N04/4577352431/sizes/o/

I have tried to connect to the same site via Firefox on a different machine, and I get the non-dodgy login, but exactly the same certficate (with the same fingerprints) as dodgy login page on the original machine.

I wonder if anybody could please advise what is going on here, and what I can best do about it.

Any help would be really appreciated. Thanks GoldenStick (talk) 10:06, 4 May 2010 (UTC)

I like the comic touch in the fake screen: (i) asking you for your PIN, and (ii) warning you about any demand for your PIN.

If matters are like this, I'd (i) remove the machine from any LAN; (ii) boot off Clonezilla to use it to copy the partition or logical drive where you keep your own files to an external drive (skip this stage if you're one of those unusual people who actually backs stuff up frequently); (iii) boot off some other Linux CD to repartition the drive and wipe out the MBR (to make changes as sweeping and deep as are possible); (iv) install your preferred OS afresh (and if I were you, my preferences might be affected by this experience); only then reconnect to the wider world. -- Hoary (talk) 11:02, 4 May 2010 (UTC)

My guess would be that the virus installed a Firefox extension that modifies the page, and that for some reason F-Secure did not notice or recognize the extension as malicious. You could try simply looking at the list of installed extensions (under Tools → Add-ons) and seeing if you can spot anything suspicious there that you don't remember installing. Failing that, you could also peek into Firefox's extensions folder and look for any suspicious entries there. If you do find something, you can send it to F-Secure for analysis, so that they'll hopefully add it to their malware database. —Ilmari Karonen (talk) 11:52, 4 May 2010 (UTC)

That is a beautiful piece of malware! It looks like they intercept your bank login and add HTML components (this might be done by redirecting you to a malicious proxy server, or a Firefox add-on similar to Greasemonkey - that appends some pretty smart javascript to your bank login webpage). That would circumvent the fingerprinting process - the page wouldn't actually be modified until it hits the client-side. It is evident that this is a hijack, and that you should not submit any financial information until you can validate that your machine is clear. Evidently, they are performing a man in the middle attack of sorts - allowing you to connect to your bank, but appending these extra fields to steal your ATM details. What amazes me most is the delicacy of programming such a precise piece of work, and then flubbing up the strings: "Password and Pin, like that: Password-PIN" does not sound like instructions from an actual bank website! It sounds like an ESL hacker! *sigh*... Your machine is compromised. If you are not capable of guaranteeing a complete removal of the malware, (which is very hard), a full reinstallation of the operating system is in order. Nimur (talk) 13:11, 4 May 2010 (UTC)

It's not really that amazing. I could whip up a quick Greasemonkey script to do something like that in a few hours at most — modifying web pages locally is what Greasemonkey is designed for — and then run it through a GM-to-XPI compiler to turn it into a standalone extension. The only slightly tricky part would be installing it without the user noticing, but I'm pretty sure any halfway competent malware writer could come up with some trick to either suppress the new extension notification or make it look innocuous, given that they already have control of your computer. —Ilmari Karonen (talk) 13:55, 4 May 2010 (UTC)

Since I don't think you can guarantee you've rid your system of the malware, I would back it up, treat the backup like deadly poison, reformat, and start from scratch. You seem very technically adept, but Wikipedia:Reference desk/Computing/Viruses is a FAQ on malware removal if you're interested. Comet Tuttle (talk) 17:06, 4 May 2010 (UTC)

My earphones/earbuds dont work

I only had them for a coupple of weeks, so they were relatively new. Today they were working one minute, and now only the left side is working properly. The jack/plug and phones/buds are not damaged and the wires are not cut. Can anyone tell me what is wrong and how i can fix it? Thanks.

Also, does anyone know where there is a good translating program that translates modern english into old english, like Shakespearian? Google Translate does not have that and I couldn't find any websites that actually have such programs. 64.75.158.193 (talk) 11:48, 4 May 2010 (UTC)

Might sound overly obvious, but I'd make sure the jack for the earbuds is plugged in completely. If it is, and you're still hearing only out of the left side, sounds like a failure in the earbuds themselves. If they didn't get damaged somehow (caught on something and pulled too hard, etc.) I'd probably return them to the store for an exchange. I'd also suggest that you repost your question about the language translator at the Language reference desk. Kingsfold (talk) 12:06, 4 May 2010 (UTC)

Spellcheck in Outlook Express

The spellcheck in my Outlook Express seems to have a French dictionary not an English one. Is there a setting somewhere that I can change? DuncanHill (talk) 16:50, 4 May 2010 (UTC)

• Hmm, I've found the Options/spelling bit, and it only offers me French - is there a download of an English dictionary somewhere? DuncanHill (talk) 16:52, 4 May 2010 (UTC)

Have you recently installed Office 2007? It seems Office 2007 changed the format of the spellchecker dictionary for all languages except French. The same dictionary is used by Outlook Express, but since only the French one is in the old format, only French appears as a valid spellcheck language in Outlook Express 6 after upgrading to Office 2007. It seems Microsoft doesn't see any need to issue an update for Outlook Express because you will all be upgrading to Vista and using Windows Mail pretty soon, right? Three years later and with many people still on XP & OE6, people are still complaining about this. See here and particularly the bit that says: "If you have Outlook Express 6.0 and installed Microsoft Office 2007 but French is the only available spell check language, you need to use a third-party spell checker. For more information, see Spell checking issues with Outlook Express 6.0". This KB article is also very helpful. Astronaut (talk) 18:54, 4 May 2010 (UTC)

Somewhere I read that you have to install Microsoft Live to get the English installed. 71.100.1.71 (talk) 19:29, 4 May 2010 (UTC)

Thanks, and yes I have installed Office 2007. Aren't Microsoft wonderful. DuncanHill (talk) 19:34, 4 May 2010 (UTC)

My monitor has the shakes

Resolved

My monitor (a Sony GDM-FW900 CRT) has developed a vibration recently, especially at the sides and the bottom of the screen (at the top in the centre it's ok). I changed the resolution (from 1600 x 1024 to 1440 x 900), but that didn't help. And if I lower the frequency (from 90 Hz to 80, 70 or 60 Hz) that only makes the vibration worse (the lower the frequency the worse it gets). Of course it could simply be that the monitor is dying, but although it's about 8 years old, it was rather expensive, so it should live longer than that (and I'd like it to last as long as possible, until sizeable LCDs that can double as a tv become more affordable). So any ideas what I might try? DirkvdM (talk) 18:05, 4 May 2010 (UTC)

How long has it been doing it and is it doing it all the time? My old CRT got the shakes maybe two or three times, and it would last a couple of days at most and then seemingly clean itself up. I never figured out the cause, but it was obviously transitory in my case. First thing I would do is make sure all connections are clean and secure - unplug the data cable and the power cable, make sure there's no crud in there, and then make sure they're both securely re-attached. Matt Deres (talk) 18:23, 4 May 2010 (UTC)

(ec) I used to see wobbles in my early Macintosh models when there was a problem with the flyback transformer, but this is not a user-serviceable part and you'd have to have a technician look at it. Comet Tuttle (talk) 18:25, 4 May 2010 (UTC)

(ec) Have the cables moved in any way? Signal bleed can cause video shake. I personally get more expensive cables simply to get better signal insulation. However, it is possible that the monitor itself is going out. The first thing I always check is the flyback circuit. Scanning online, it looks like it is in the back left (when facing the screen). Listen to it closely (without removing the case). Do you hear gurgling? If so, it is going to die and it will most likely be cheaper to buy a new one than replace the broken parts. I hope fiddling with the cables improves it though. I've always hated that it costs more to repair a good monitor than it costs to replace one. -- kainaw™ 18:28, 4 May 2010 (UTC)

I found that this is more of a problem with my CRT when showing brighter pics. I therefore set my background color, both on my desktop and here in Wikipedia, to black, and also turned the brightness down, and now it's fine. StuRat (talk) 18:31, 4 May 2010 (UTC)

Ah, thanks Matt! I thought the connections should not be a problem because I had them screwed tight, but wriggling the connection to the monitor (required a bit of 'caving' to reach it) solved the problem. As a friend of mine says, always start with checking the hardware-connections. I should listen to him more often. :) Anyway, I'm glad it turned out to be something as simple as this. Thanks! DirkvdM (talk) 19:10, 4 May 2010 (UTC)

Creating a clickable icon for Command Prompt commands

Any suggestions on how to create a desktop icon that will run several command prompt commands? So the user never has to deal with the command line stuff? Just double click an icon to run several commands (running several Ruby scripts). --70.167.58.6 (talk) 18:28, 4 May 2010 (UTC)

On Windows? I (personally) have, in the past, created .bat files (a text file containing the commands, one on each line, AFAIK), which you can then create desktop shortcuts to, as I have. Hope that helps, - Jarry1250 ^{[Humorous? Discuss.]} 18:31, 4 May 2010 (UTC)

simultaneous two-way communication on telephone

I'm pretty sure that traditional land-line telephones allow both parties on a call to speak and be heard at the same time. With my cheapo mobile phone and service (Virgin mobile) this is not the case; if the two people try to talk at once only one person can be heard at time, which I find very annoying. My question is, is this always the case with mobile phones? If not, what is most likely the source of the problem, the cheap phone or the cheap service? ike9898 (talk) 18:55, 4 May 2010 (UTC)

The question is asking about duplex (telecommunications). Most handsets and networks are actually fully-duplexed (and support simultaneous transmission and reception) - though some very uncommon units and networks are only half-duplex (either transmit or receive, but not simultaneously). However, the situation for modern digital phones (including land-line analog POTS phones, which connect to a digital network through a compatibility layer by the provider) is a bit more complicated. Even if duplex mode is supported, advanced digital squelch, echo cancellation, noise suppression, and automatic gain control may all be operating on the signal as well. These can be installed as software or hardware inside the handset, or may be realtime processing steps applied to data as it transits the telecom network. This is, technically, a "feature" and not a "bug" - although it is annoying, because it is somewhat unintuitive - especially if you want duplexing behavior. Any combination of these technologies may effectively squelch (mute) your signal, with the intention of improving your ability to hear the other party (especially at low-bitrates or in ambient-noise environments). In practice, this interferes with the ability to fully duplex, even if the handset and network permit it. Nimur (talk) 19:11, 4 May 2010 (UTC)

Thanks. The part that I still don't understand: If I were using a different commonplace consumer phone and/or a different commercial network, would I likely experience this problem less? ike9898 (talk) 19:49, 4 May 2010 (UTC)

Not really sure what Nimur is talking about, TBH. The fact is that mobile phone systems (the network and handset) are designed to support both parties talking at once. However, owing to the time taken to code the speech into the digital radio communication, there is a delay between one party speaking and the other hearing. That can mean that it appears that both are trying to speak at once, and both then stop. So talking simultaneously on a mobile phone is quite possible, but what is heard will be somewhat different, owing to the delay. --Phil Holmes (talk) 20:26, 4 May 2010 (UTC)

Here is a patent for POTS with squelch (1974); here is a patent for a thresholding squelch for wireless phone (1978); here is a squelch patent for TDMA (old-style digital mobile telephone) (1999), here is Application Note AN014 from Texas Instruments describing software squelch for CDMA (modern American-style mobile phone); here is a book, Data over Radio, (1992), discussing CTCSS and more advanced digital squelch for packet-switched mobile telephoney, and here is a patent for squelch in GSM. As you can see, every major mobile telephony platform (analog, digital, TDMA, CDMA, WDCMA, GSM, 3G, whatever), all use a digital squelch or conversation-suppressor, even though they are capable of bidirectional transmission. This is a design feature; it improves the effective signal to noise ratio of the audio, and allows lossier compression (ergo, lower bandwidth). You can, if you so desire, describe squelch as an extremely low frequency lossy compressor: it turns low volume (rather, un-keyed) conversation into "zero data transmitted," even though the telephone supports duplex mode. Nowadays, because squelch is often software-controlled, the mobile phone may opt to permit only one party to transmit, and mute the other, by "estimating" which one of you is talking (by simple analysis of volume threshold, or more sophisticated frequency or pattern detections). If the system always opts to squelch one of you, but you are both talking, you will confuse the software squelch or cause it to thrash between the two parties - hence the strange digital noise you may hear. Nimur (talk) 21:31, 4 May 2010 (UTC)

Visual Basic V6 versus VB.NET

While you might expect differences in programming language versions it never ceases to amaze me how even the most fundamental functions or statements in VB6 are not carried over to VB.NET. Below is an example of such fundamental code that runs fine under VB6 but will not produce the same results using VB.NET. While the code editor provides indents and line numbering that are helpful features how can VB6 programmers use the VB.NET version (find workarounds and fixes) when even the VB.NET converter and docs do not deal with such issues? 71.100.1.71 (talk) 19:25, 4 May 2010 (UTC)

 For i = 1 To v ^ k
 Q(i) = 0
 For j = 1 To v ^ k
 bi(i, j) = Spaces(k)
 Next j
 next i
 '------------------------------
 For i = 1 To v ^ k
 T = i - 1
 For j = k To 1 Step -1
 D = Int(T / v)
 ah(j) = T - D * v
 T = D
 Next j
 For l = 1 To v ^ k
 F = l - 1
 For j = 1 To k
 D = Int(F / v)
 E = F - D * v
 F = D
 If E <> 0 Then
 Mid(bi(i, l), j, 1) = xi(ah(j))
 For M = 0 To g
 If ai(M) = bi(i, l) Then Q(i) = 1
 Next M
 End If
 Next j
 Next l
 Next i

VB6 and VB.NET are clearly quite different platforms; the VB.NET article discusses whether it should be considered a new version, or a different language altogether. This article covers how one might migrate from VB6 to .NET. The assumption that VB.NET is compatible (or even tries to be) seems to be false, as is a belief that the automated conversion is anything other a partial solution. If one wants to develop for VB.NET, one needs to acquire the skillset necessary for coding for that platform. -- Finlay McWalter • Talk 20:37, 4 May 2010 (UTC)

If there is not a simple and straightforward fix for the code above, which will allow it to run under VB.NET then I'll start calling it Vista.NET and relegate it to the pile of software that sacrifices the real in the course of providing the illusion of having achieved the ideal. 71.100.1.71 (talk) 21:21, 4 May 2010 (UTC)

It's a totally different language that happens to preserve some of the basic grammar of VB but that's about it. It's not the same and whatever you want to call it, don't be confused by trying to consider it VB. Personally I think it is a half-language between VB and, I don't know, Java or C or something... superficially VB-like but with all of the pain-in-the-neck qualities of the latter that VB was supposed to let you avoid (like having to deal with memory management and complicated threading systems and etc.).

With that specific code... I think you will have to declare and type your variables explicitly, for one thing. I think everything else should handle reasonably similarly... that is, I think for/next loops and arrays handle the same way. You may have to explicitly include the Strings and Math modules in order to use Mid and Int. I can't recall; I haven't used VB.NET for awhile and it always takes a little work to get my brain back in gear on it. --Mr.98 (talk) 21:37, 4 May 2010 (UTC)

Don't worry about it. I've pretty much reached my conclusion that if my kids want to follow in my footsteps to do it somewhere besides where I work. (No offense Microsoft.) 71.100.1.71 (talk) —Preceding undated comment added 22:01, 4 May 2010 (UTC).

Interesting. I looked at that code and thought you could get away with the typing. I'm pretty sure .NET will baulk at that Mid() function, which I'm not entirely sure actually exists in .NET. It acts as String.subString(), right? So you need to use that (with an implicit conversion, by the looks of things). Just my 2c though. - Jarry1250 ^{[Humorous? Discuss.]} 21:48, 4 May 2010 (UTC)

Reading the docs such as they are I for awhile tried to write my own functions for mid and int and strdup, etc. but these all had the same coding problem. I tried Option Explicit and watched the warning messages carefully and fixed the problems they cited one by one. Yet VB.NET could still not run this simple code. Maybe Microsoft farmed out VB to be upgraded and improved and brought into the future by persons already in a different reality far from where the real future will actually go. 71.100.1.71 (talk) 22:06, 4 May 2010 (UTC)

VB.NET does have Mid and Int functions but I think you have the import the relevant library. I think you have to do something like this:

Imports VB = Microsoft.VisualBasic

And then refer to them as VB.Int() and VB.Mid(). Maybe. Again, I'm rusty (and on a Mac, so trying it before telling you is hard!). Anyway, again, I agree VB.NET is kind of stupid. At this point I would just tell people to learn C or Java; all of the simplicity of VB has been sucked out of the language, and if that's the case, what's the point. --Mr.98 (talk) 22:46, 4 May 2010 (UTC)

Perhaps you are thinking of importing Excel using the import directory rather than math. In any event I completely agree that replacing such basic (literally) statements and functions with some sort of system contrived to supposedly add functionality and instead making the language disfunctional is never the way to go, unless of course you are trying to form a C# or C++ Guild and want to destroy all competition. 71.100.1.71 (talk) 23:14, 4 May 2010 (UTC)

I'm not sure I understand your first sentence. Did you try adding the "Imports" line to your code and changing the functions as I suggested? That ought to work... --98.217.71.237 (talk) 01:04, 5 May 2010 (UTC)

I wouldn't really call it is dysfunctional language. :) VB.Net has a different set of priorities to VB6 - the main change being a requirement to run under the .NET framework, and that therefore entails that it needs to be Object Oriented and to employ stricter typing, amongst other alterations. These are significant changes, effectively making a new language with a common core syntax. I tend to see VB.Net as an option for VB6 developers: if you wish to migrate to the new OO and .Net paradigms, here is a language which retains the syntax, more-or-less, of what you used before, even though it's not the same language, and this may make the transition easier. However, from my perspective, the move to OO is actually the hardest part of the change, so keeping the syntax consistent offers little advantage. The problem with the above code isn't so much that the various functions don't exist in VB.Net - they do, (although they need to be called differently), and thus the algorithm could be implemented in VB.Net using very similar statements - but that the code is unstructured, and would need to be converted to OO. Thus I tend to argue that it makes as much sense just to move to C#, as if you need to learn a whole new paradigm anyway, you might as well pick up a C-type syntax while you're at it. :) - Bilby (talk) 23:40, 4 May 2010 (UTC)

I could find no reference as to how int might be called differently except perhaps as a function. Calling it as a user function did not change the results. I use to write short C routines so perhaps that is the better course. 71.100.1.71 (talk) 23:51, 4 May 2010 (UTC)

Tinkering with browser source code

Is any browser simple enough so that an amatuer like myself could tinker with the source code to rectify irritating features or quirks they dislike, or conversley implement special features of their own? Or is it all way too complicated? Can it also be done in ten minutes rather than ten hours? Thanks 92.29.62.241 (talk) 19:30, 4 May 2010 (UTC)

I don't know anything about programming, but perhaps developing a Firefox addon would be easier than delving into browser source code. The Mozilla website has guides for creating extensions that should help too 82.43.89.71 (talk) 19:35, 4 May 2010 (UTC)

A modern browser has a huge number of features, not all of which are necessary for the basics of browsing the web. It really helps to know a few things about what a "web browser" actually is: at its core, it has a network layer that understands the HTTP protocol, and a layout engine that understands how to convert HTML into a graphical "picture" with text and images in the correct locations. Modern browsers like Firefox also do much more - storing bookmarks, managing complex tabbed browsing, handling sessions, saving graphical preferences, enabling rich multimedia plugins, understanding other protocols (like HTTPS, FTP, and others), hosting a scripting environment for JavaScript and other languages, and so forth.

As such, although Firefox is totally open-source, it is horribly inaccessible if you are a novice. You might want to look at a bit more primitive "browser", such as the Jakarta HTTPClient. You should be familiar with programming and the basics of how network sockets work; but you can read this sourcecode and documentation without being overwhelmed by the "peripheral" features. Note that HTTPClient does not have a rendering / layout engine. Alternately, Gecko (layout engine), which drives Firefox, is a powerful HTML layout utility, but is not a "browser" because it has zero internal knowledge about network connections - it just parses HTML documents that you feed into it, and makes them look nice on a screen. You can play with Gecko independently from the full Firefox source code.

Lastly, as has been pointed out above, if you just want to tweak up an irritating feature of Firefox, you might be better off developing a Firefox extension or learning to use Greasemonkey. These will give you a lot of control over user-interface without requiring in-depth knowledge of the system internals. Nimur (talk) 19:44, 4 May 2010 (UTC)

I think this falls under the category of, "if you have to ask, the answer is probably 'no.'" I mean, I wouldn't know how to modify the source to be able to change specific features or add new ones, but I do know that even optimistically this would fall way outside the "ten hours" requirement (and certainly more than ten minutes)—even small, trivial changes are likely to take you a lot longer than that if you don't understand how the whole system works together. Even developing a simple Mozilla extension for Firefox is likely to take you more than ten hours the first time around. If you had the requisite knowledge to do this, you wouldn't have to ask us how hard it is... you'd know. --Mr.98 (talk) 22:40, 4 May 2010 (UTC)

How do I determine the URL and then capture a live video stream? (using vlc).

I have WindowsXP and use the graphic interface of the (free) "VLC media player 1.0.5 Goldeneye" from videolan.org. I also use FireFox 3.6.3 with the installed add-on: "Video DownloadHelper 4.7.3"

Why: I need to save video streams because, in most cases, such content tend to be lost (moved, completely removed or no longer freely availabe) before the time I want to take a look at it again.

What: Now I want to capture and save some video streams from a public broadcaster (NRK) web-TV site. For instance the stream on the page: http://www.nrk.no/nett-tv/klipp/630814. (Which is a norwegian language version of a BBC documentary on Supervolcanoes).
When browsing it in FireFox then the web page first, automatically, determines the speed of my internet connection and then, whithout any problems, shows me the video.

Problem: Video DownloadHelper seems to ignore that there is any video-stream on the page.
And if I use VLC and choose: "Media -> Open Network Stream" and then enter: "http://www.nrk.no/nett-tv/klipp/630814" in the address field, then no video is shown (or saved).

Questions:

1. How do I get VLC to sniff out the correct URL of the video stream itself (as opposed to the URL of the web page where the video is embedded)?
2. How do I get VLC to save the stream to my harddrive?

Excuse: I know, I know: "RTFM!", but I have looked at what I believe to be the most relevant help page: http://wiki.videolan.org/Documentation:Streaming_HowTo/Receive_and_Save_a_Stream and I am overwhelmed and do not understand anything! Partly because I do not know much at all about video streaming in general, and partly because unfortunately I do read very slowly, therefore figuring out this problem seems a somewhat insurmountable task to me. ;-(

Request: If someone would tell me exactly what I have to do — preferably by less than a 143 words ;-) — then it would be really helpful to me!
Could you please help me?
--Seren-dipper (talk) 21:19, 4 May 2010 (UTC)

[1] 82.43.89.71 (talk) 21:36, 4 May 2010 (UTC)

I can't read Norwegian, but does it say that it requires Microsoft Silverlight for the videos? If so, you might be out of luck. I don't think VLC can save Silverlight streams (which are encrypted under proprietary DRM) at the moment... Googling around, I'm not sure any of the many stream-saver programs can, yet. Maybe someone else knows better though. You could always use screen capture software to grab the video as it streamed (e.g. CamStudio), though this has its downsides (large files, takes a lot of active CPU time). --Mr.98 (talk) 22:34, 4 May 2010 (UTC)

HDMI Audio Problems

I am attempting to connect my laptop to my tv through HDMI. The video works fine. The audio, however, is not working at all; although, it has worked in the past. I changed the default playback device to the digital output and nothing comes out even though audio is playing.

I am running win 7 Home Premium (64-bit) on an HP Pavilion dv6700 (p/n: KL090AV) with BIOS version F.59. My audio driver is Realtek HD Audio.

HP is not helpful and keeps telling me that since I upgraded to windows 7 from the factory installed Vista, they can't help me. (One was so bold as to recommend that I reinstall Vista!)

Thank you! --omnipotence407 (talk) 22:54, 4 May 2010 (UTC)

Dell did that to me once, too, where I upgraded the version of Windows and they started refusing to help me until I jumped up and down and insisted it was a hardware problem and demanded to talk to a supervisor and so forth. Super frustrating. But this may be a path to getting them to help you. On, perhaps, an external USB drive. Install Vista on an external USB drive and install the HP-provided drivers, and if the problem is still occurring then ring up HP and raise a fuss. Comet Tuttle (talk) 00:39, 5 May 2010 (UTC)