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June 29

Playing Downloaded .cue & .flac files

I have downloaded some music (my first time) and find I have a .cue and a .flac file for the piece I downloaded. What needs to be done for one or both of these to become a playable sound-file on my Windows media player? Can anyone help a musical newbie please? Gurumaister (talk) 07:30, 29 June 2011 (UTC)

Sorry, I don't know the answer, but this looks helpful. Tama1988 (talk) 08:12, 29 June 2011 (UTC)

A .cue extension is not an audio format in itself, but a text document that says how a CD's tracks are laid out. I don't have any experience using them. The way I would play FLACs would be to not use Windows media player, but rather a free player that will play those file formats without trouble. I like VLC media player, but see Comparison_of_video_player_software#Audio_format_ability for other options. Otherwise, the link Tama provided is your best bet for getting FLACs to play on Windows Media Player as is. Finally, you could convert the FLACs to a different audio format that is supported, like mp3: see this guide. There are lots of free audio format converters available. But if it was me, I'd rather just get a free media player that can play everything, rather than get a free audio converter, and then play the music on a non-free program. Buddy431 (talk) 05:39, 1 July 2011 (UTC)

Moderate (or just slight) network security for dummies

Or anyway a dummy: me. Sorry, there's something about networks: whenever I try to read how they work, I get totally confused and give up. Anyway, I have a dumb wired/wireless security question.

I work in a large organization. There are ethernet sockets all over the place. Anyone can bring any computer, plug it in, and get to the web. Here's the process: Point your browser to any URL, and up will pop the log-in screen. Feed that your ID and password, and you're in -- thereafter you can browse and download freely. (Surprisingly, you can do this for two computers at the same time. Though there seems to be some prohibition of bit torrents.)

I use this for such purposes as online purchases, when I divulge my credit card details. (Of course only with https and when I see the browser's little closed-padlock icon.) Is this stupid of me?

There are also wireless LAN access points all over the place. There's no encryption at all -- you too could stroll in (or sit in your car outside) and you'd get to the log-in screen. Even when I'm "https, closed-padlock", I avoid giving credit card details, etc, when connected wirelessly. Is it stupid of me to be worried?

The organization has just added a second wireless LAN (or second SSID). This one is password protected. However, it's a single password for everyone, and there's effectively no protection of the password. (If you wanted it, you could easily find it online.) I don't follow the logic here (but recognize that I'm an ignoramus). Does (A) an SSID that's encrypted but whose password is public knowledge have any advantage over (B) an open SSID? Tama1988 (talk) 08:04, 29 June 2011 (UTC)

Your primary question appears to be: Is https security safe? The quick answer is: Yes. The deal with networks is that it is layered. On the wires themselves, you have little 1's and 0's moving along (technically, they are electrons). From endpoint to endpoint, the hardware speaks a specific language. This is a packet-based language. One item of hardware will grab an imaginary packet (or envelope), put some information in it, slap an address on it, and send it to another one. The wires see 1's and 0's. The end hardware sees packets. Your software on your computer speaks in streams of data, not packets. So, you send an email. Your whole email streams out to the hardware. The hardware chops it up into chunks that will fit nicely into a packet. Each packet is sent off to the end recipient hardware. On that end, the hardware takes all the information out of the packets and streams it to some software on the other end. It should be obvious here that the little packets don't all take the same route from one place to another and don't necessarily travel in order. So, if I grab a packet off the internet, what do I have? I have a small chunk of some stream from some program. Useless. I have to get close to your computer's hardware to grab all the packets and then I can put them back together. So, there's another thing that you can do. You first contact the server you want to send something to. You put a secret key in a lockbox and put a padlock on it. That is sent to the other server. The other server puts its padlock on it and sends it back to you. You remove your padlock and send it back to the server. The server removes its padlock and reads the secret key. This could go the other way (the server sends the key to you), but what is important is that there is never a case where the secret key is travelling over the network without being locked (encrypted). Now, you and the server have a secret key that is very long and that you will use only one time. You encrypt your message with it. Stream the encrypted message to your hardware. The hardware packets it and sends it as 1's and 0's over the wires. Eventually, the server gets it and decrypts it. That is a very loose description of https. If someone were to be watching the 1's and 0's, they have many hurdles. First, they need to get all the packets. Then, they need to order them. Then, they need to decrypt the message - which is the hardest part. Because the message is short and the key is huge and never used again, decryption is nearly impossible. Notice that none of this has anything to do with being wired or wireless. -- kainaw™ 12:56, 29 June 2011 (UTC)

OK, I got it--as far as https goes, at least. (And yes, I do check all the signs that I really do have a proper https connections (not that I'd previously understood what that meant). Tama1988 (talk) 00:19, 30 June 2011 (UTC)

Windows Network Security. Pick two. Googlemeister (talk) 14:45, 29 June 2011 (UTC)

Network and security. I don't see how the OS is directly relevant to my question, but FWIW I don't use Windows. Tama1988 (talk) 00:19, 30 June 2011 (UTC)

As Kainaw said HTTPS pretty much guarantees no one in between will be able to decrypt your content without the cooperation of either end of the connection. So the issue is not so much do you trust the network but do you trust either end? The bank or whatever should not be a big concern. But what about the computer you are using? It's not clear to me if this is a personal computer or a work computer. If it's a work computer, do you trust whoever has adminstrative powers not to do something dodgy, e.g. install a keylogger or install a modified browser which makes you think you are visiting a secure site with a secure certificate verified by one of the normal root certificate agencies? Do you trust them to ensure no one other then them can modify the computers either locally or remotely (whether directly or with malware) to do one of those? If it's your own computer do you trust yourself to ensure your computer is secure and no one can do something like that? The 'remotely' part is perhaps important here, are your firewall and network security settings properly set up? Some OSes may give lower security on a LAN thinking the other computers are more trusted, but this is probably a bad idea in a work place (although not as bad as a public wifi access point or if you have dodgy flatmates since the network admins will often at least try to restrict what goes on in the LAN and there would be greater concern of the legal risks). Nil Einne (talk) 15:16, 29 June 2011 (UTC)

It's one or other of my computers. Nobody else has ever touched any of them. They're running Debian stable, fully updated and only from the right repositories. (There may be a common idea that Debian is for computer experts but it was pretty easy to set up and anyway I am no computer expert. And I know next to nothing about networks.) I haven't encountered any obvious restriction on what goes on via the LANs other than the prohibition of torrent downloads; the article on firewalls talks about "packet filtering" and maybe there's some of that; I wouldn't know.

Back to the first question. An institution has (A) a wired LAN that requires a personal ID and password. It also has (B) a wireless LAN with no additional requirements. It then adds (C) a second wireless LAN (or SSID) that requires a password for any use (before you get to the personal ID/password web page), but makes this additional password pretty public. "Common sense" tells me that (C) has no advantage over (B), but am I missing something here? Tama1988 (talk) 04:42, 30 June 2011 (UTC)

If the password is associated with WPA then the over-the-air content will be encrypted and even your non-https traffic with be difficult to impossible to read using wireless sniffers. --Phil Holmes (talk) 11:26, 30 June 2011 (UTC)

Ah, I think I've got it. By making the password to the SSID available, the organization of course lets anyone use it, but even if black hats are using it, then as long as it's WPA (and I'm ashamed to say that offhand I don't know if it is WPA), it's going to be difficult for these black hats to snoop at what I'm doing. I'm starting to get the picture ... I think. (I wonder if it's just me who's utterly baffled by network stuff, despite being unworried by most other day-to-day computer-related issues.) Tama1988 (talk) 09:43, 1 July 2011 (UTC)

How to creat a mobile phone app

So, I've got an idea for a mobile phone app. I've looked extensively through other similar apps, but have not found anything quite like what I envision. Without saying too much, the concept of the app is very similar to existing apps...just the "purpose" is different, and is what makes my idea unique. Anyway, a number of trusted friends I've talked to about this think its a really good idea, and something they would probably pay for. The problem is, I have no knowledge of even where to begin. Is there a good resource to teach myself how to create an app? Quinn ^{❀ BEAUTIFUL DAY} 16:18, 29 June 2011 (UTC)

It depends on the phone. iPhone apps are programmed in Objective C and you really need a Mac; then you get the iPhone SDK from Apple. Android apps are written in Java or C and you get the Android SDK from Google. J2ME apps are written in Java, and you get the SDK from Oracle. All three are fairly different environments and porting code from one to another isn't a trivial matter. -- Finlay McWalter ☻ Talk 16:28, 29 June 2011 (UTC)

I suppose since I have an Android, that I would go that route. What is an SDK? Quinn ^{❀ BEAUTIFUL DAY} 16:29, 29 June 2011 (UTC)

Software development kit. -- Finlay McWalter ☻ Talk 16:31, 29 June 2011 (UTC)

All of the phone platforms have developer guides like the Android Developer Guide. -- kainaw™ 16:30, 29 June 2011 (UTC)

Perfect! Thanks! Quinn ^{❀ BEAUTIFUL DAY} 16:53, 29 June 2011 (UTC)

Ad problems, the sequel

Referring back to this question, I have new information to add.

Some of the ads still appear, but not after I click any more. They gradually cover the screen after I have been at a particular location for a few seconds, and the "Close" link appears quickly (this didn't happen before) and works quickly enough (it was slow to do anything). Once, though, I thought I was clicking on "close" and ended up clicking on the ad itself, which was annoying. Anyway, these particular problems seem to be resolved.

There was one case where the "close" link was hard to find, and it said "roll over", whatever that means. So someone needs to explain themselves better.Vchimpanzee · talk · contributions · 18:21, 29 June 2011 (UTC)

The people who run the websites get paid if you click on an ad. It is in their best interest to do everything possible to make you click on the ad. So, why would they make the ad small, out of the way, and give it a big "Close Me" button? The solution is to stop visiting sites that use annoying ads. If nobody visits them, they will look for another way to make money. -- kainaw™ 18:36, 29 June 2011 (UTC)

I'm not going to stop visiting such sites. They need to be nice to their users. A big "Close me" button is the only way to do that when what you want has been covered up without your permission. They will hear from me otherwise and be told I will avoid doing business with any of their advertisers.Vchimpanzee · talk · contributions · 19:26, 29 June 2011 (UTC)

I'm certain they'll be impressed. --Tagishsimon (talk) 20:03, 29 June 2011 (UTC)

Of course, Jack in the Box and Citi have poisoned their reputations (in my view).Vchimpanzee · talk · contributions · 20:05, 29 June 2011 (UTC)

I just visited their sites and Idon't see any particularly obnoxious ads. Are you sure those ads are theirs? With respect to "I won't stop visiting their sites... I'll avoid buisness with their advertisers". What happens is you visit sites and click ads, on accident maybe, but that is you "doing business with them" and probably the only business they expect to get anyway. So they're already winning, so is the site you are visiting, who gets paid by the advertiser, and you lose by having yourself annoyed. The solution is either to use an ad blocker or stop interacting with sites who do this, ie don't go to that site. Of course, I'd verify it was the site popping these ads up, and not some sort of spyware/virus. Chris M. (talk) 20:38, 29 June 2011 (UTC)

I've already stated it's up to the library whether to use an ad blocker. And I did say the obnoxious ads no longer seem to be a problem.Vchimpanzee · talk · contributions · 21:14, 29 June 2011 (UTC)

Roll over usually means move your mouse cursor over the ad for it to popout or display something. In such a case avoid moving your mouse over the ad. Nil Einne (talk) 23:08, 29 June 2011 (UTC)

If these are library computers I suppose they are using Windows. (Why should a library use free software when it can instead use software that costs money?) If so, I'd click Alt-F4 at the sight of any obnoxious pop-up. There's no guarantee that either "Close" or a little "x" on a junk window will work to close it.

Further, if you anyway have a computer and sites look bad on computers over which you have no control, then prepare your own computer properly and thereby view garbage-free versions of the sites. Tama1988 (talk) 08:21, 30 June 2011 (UTC)

Alt-F4 will close the whole browser including any tabs (if the OP ever gets round to using them) which isn't what the OP wants. And it's also a little silly to get so paranoid about ads, I probably spend less time closing them then people do worrying so much about them and I've never found the need to use a popup blocker or ad remover other then what comes with my browser (even when visiting dodgy websites). Also with the vast majority of ads on non dodgy websites, clicking the x or close will remove it. Note we are not talking about popup windows here as explained in the op's earlier post but ads which display in the current browser window sometimes hiding the content completely until they are closed (or your browser doesn't visit the actual content until the ad is closed). The op apparently does not want their own computer and from memory of their user page needs to be careful with money so telling them to get one just to view news websites, even despite their persistent posts about issues with library computers is about as helpful as telling someone who is looking for reviews of US health insurance companies for individuals that they should move to Canada. Besides that from all the comments we have seen from the op it's questionable if a computer they have to administer themselves will be any better. Nil Einne (talk) 12:14, 30 June 2011 (UTC)

If you've seen my user page you know I have a computer. I don't use it to go to these problematic sites. It's not silly to get paranoid about ads because if they cause these problems it makes things very complicated. I don't need any further complication. And I'm not going to close the browser and I do not, will not, use tabs. I don't know how to get through to everyone. My mind does not and will not work that way. Windows are at the bottom of the screen. That's it.

And as I've said the problems seem to be resolved for now.Vchimpanzee · talk · contributions · 13:45, 30 June 2011 (UTC)

Just once in my life my computer (Win 2000 at that time) suddenly exhibited extraordinary symptoms of something. The browser (probably Mozilla Suite, though I forget all the details) showed screwy looking web pages saying rather alarming things. Then a very authentic-Microsoft-looking warning window popped up, suggesting that I install some antivirus software. The warning didn't have any spelling mistakes or obvious giveaways, but I couldn't imagine that I had deliberately installed any software that would detect a "virus" (malware), let alone any that would detect malware and do nothing with it other than prompt for the download of some other software. Somehow I guessed that the additional software would require credit card details, etc etc. I was less worried by any "virus" than by phishing and the rest. It seemed that some repellent bottom-feeding scam had managed to get one or two tentacles onto my computer, if you'll excuse the mixed metaphors. I don't remember if there was a "Close" button, but there certainly was a little "x". Given that the pop-up was designed to delude me into divulging my credit card info (or similar), I had no particular reason to think that clicking "x" would close the window--it might do something very different indeed. And so I hit Alt-F4.

Of course I don't recommend hitting Alt-F4 (or the non-Windows equivalents) at the sight of any ad. Perhaps I misunderstood the question, which I thought was about something serious. At the same time, I don't understand why anyone who has heard of AdBlock (Plus) wouldn't want to install it or something serious. Tama1988 (talk) 10:00, 1 July 2011 (UTC)

Now I see why there were those talking about Alt-F4. I should mention the library computer I had this problem with the most was Mozilla Firefox. I did, however, in one case get a virus or malware warning with one of these ads, and that was with Windows. Apparently some software the library had blocked the ad due to potential problems, but just that one time. I clicked on "Back" and that solved the problem (But if I do that I have to figure out how to get back where I wanted to be). But I don't click on the red X because I don't want to quit. As I said, the "Close" message has been easy to see in all cases recently. The "roll over" message was at the bottom and I wouldn't likely have seen it. I don't even know how I did.Vchimpanzee · talk · contributions · 15:55, 1 July 2011 (UTC)

HFS+ drive backed up onto FAT32 drive

A while back my family's iMac started experiencing troubles and we had to reinstall OS X. Before that I used Data Rescue II to back up the clone the contents of the disk (200+ GB) to a .dmg on a FAT32-formatted external hard drive. The .dmg is 4 GB—obviously nowhere near 200 GB—and cannot be mounted. I think that Data Rescue may have split it up into blocks and scattered them through out the drive, which is a Western Digital 1.5 TB My Book Home Edition. Viewing the information about this drive with Disk Utility reveals that it is 1.4 TB (which Disk Utility shows as 1,500,301,910,016 bytes—marketing, huh, 1.5 terabytes with 1 terabyte being equal to 1000^4 bytes instead of 1024^4 bytes) and that its capacity is 1.36 TB, a discrepancy. Could my "scattered" backup somehow be in this discrepancy? --Melab±1 ☎ 18:47, 29 June 2011 (UTC)

Marketing does not use powers of 2 when using MB, GB, TB, etc... They use "thousands" increments. If you want to be technical, it was the computer programmers and hardware engineers who incorrectly called 1024 bytes a kilobyte. So, all you have here is a disagreement between what you want kilo to be and what the mareting department is calling kilo. As for the actual size discrepancy, it is expected that the overhead required by the filesystem will take up room on the disk. The larger the disk, the more overhead you have because there is a lot of indexing and free-space management going on. Your data shouldn't be anywhere in the disk overhead area. As for having a file scattered around a drive - that is normal. There is no reason that a drive must keep a file in one continuous chunk. It is nice for humans to find a file in one piece, but a computer will happily hop around the drive grabbing up the little chunks to make one big chunk. -- kainaw™ 18:57, 29 June 2011 (UTC)

I know that marketing uses powers of 1000. Using the numbers that Finder displayed, I have around 74 GB on it. Remember that I backed this up into a DMG which reached the 4 GB limit of FAT32 files and I also did a deleted files recovery with Data Rescue 3 a few months later, probably contributing to the 74 GB. What I want to know now, is can I reconstitute the old backup? --Melab±1 ☎ 19:26, 29 June 2011 (UTC)

How can I reconstitute this back up? --Melab±1 ☎ 22:40, 29 June 2011 (UTC)

Make sure you show all files including hidden, system and protected files and look at the disk. Do you see any other files other then the single DMG? If not there's a very good chance the backup is not there, probably not carried out properly in the first place. Nil Einne (talk) 23:05, 29 June 2011 (UTC)

A few months after this I stored some recovered files on drive after I accidentally deleted a VirtualBox snapshot. --Melab±1 ☎ 23:36, 29 June 2011 (UTC)

What is the possible compression ratio of DMG files? --Melab±1 ☎ 00:43, 30 June 2011 (UTC)

That would depend entirely on the source content, Apple Disk Image says bzip2 (and others) is supported. Unless your content was nearly completely text files or something similar, a 50:1 compression ratio is very unlikely. It is also unlikely storing further files on the drive removed your backups although if the backup was done but somehow deleted it could have greatly reduced your chance of recovery. However I still go by my earlier comment, if there are no other files on the disk that you don't recognise there is likely no further backups and the most likely possibility is your backup wasn't carried out properly. I realise I forgot to mention this but you should always verify your backup before you need it, which means amongst other things, make sure any backup you carry out is done properly. Nil Einne (talk) 12:02, 30 June 2011 (UTC)

Shell script help

Resolved

Hi. I'm writing a little shell script and can't quite find the right way to do it. I have a gazillion files. In each file, each line is comma separated with words and numbers. But in a file, each line has a different number of entries, and the numbers and words are different lengths. I want to extract the number in the nth row, mth column of each file. I can get the nth row with "sed -n 2p" but I can't extract the mth entry on that line (which is a number). What is the best way to do this? Thanks, Robinh (talk) 21:32, 29 June 2011 (UTC)

You could use awk, as in this example: echo "hello,there,folks" | awk -v foo=2 -F"," '{print $foo}'

Where -v foo=2 sets the awk variable foo to 2; you'd set it to whatever m you wanted

and -F"," sets the field delimiter to a comma

-- Finlay McWalter ☻ Talk 21:47, 29 June 2011 (UTC)

A slightly more succinct version of which is awk -vm=1 -F, '{print $m}' -- Finlay McWalter ☻ Talk 21:48, 29 June 2011 (UTC)

Put more simply: awk -F, '{ print $m; }' ¦ Reisio (talk) 22:00, 29 June 2011 (UTC)

Thanks guys. Works perfectly. I've never really got to grips with awk. Cheers, Robinh (talk) 22:12, 29 June 2011 (UTC)

That's a workable solution, but if speed matters, it would be quicker to use cut rather than awk; that is, cut -d "," -f $m. Looie496 (talk) 23:58, 29 June 2011 (UTC)

Heh, even better! thanks again, Robinh (talk) 01:12, 30 June 2011 (UTC)

web designing tutions online for beginners [80 years old, Me]

I am Sunder Thadani, a netizen from Mumbai [age-80 years]. I wish to learn web designing. I need help/guidence on online tutions from the web [fee-free]. I have lates PC with Windows 7 and Office 2010 as platform. My knowldege on computer is good since I am using Net since 1999. Your attention will be highly appreciated. Sincerely, Sunder Thadani — Preceding unsigned comment added by Sunder360 (talk • contribs) 22:53, 29 June 2011 (UTC)

http://wsc.opera.com/ http://www.htmlhelp.com/ http://css-discuss.incutio.com/ http://www.brainjar.com/ http://www.htmldog.com/ http://css.maxdesign.com.au/ http://www.alvit.de/handbook/ ¦ Reisio (talk) 23:12, 29 June 2011 (UTC)

W3Schools is very helpful. --Melab±1 ☎ 23:37, 29 June 2011 (UTC)

Or was it harmful? http://w3fools.com/ ¦ Reisio (talk) 23:45, 29 June 2011 (UTC)

HTMLdog is also helpful. Unlike Resio, I also find w3Schools to be extremely helpful. TheGrimme (talk) 13:44, 30 June 2011 (UTC)

No doubt because you aren't informed enough to identify it as harmful. Check out the link. ¦ Reisio (talk) 18:29, 30 June 2011 (UTC)

Helpful or harmful depends on your opinion. But let's make clear: w3schools is a privately-operated website that is not affiliated in any way with the official World Wide Web Consortium (W3C) standards body. Nimur (talk) 17:47, 1 July 2011 (UTC)

June 30

Creating a mobile phone app part 2

Crap. So, I read through a good portion of the Android tutorial on creating mobile phone apps, and found out very quickly that it goes way over my head a short way into it. So, what if I want to recruit someone to develop this mobile application for me...what's the best way of going about it? I don't have any close friends that have this type of skill set, so I am looking for the best way to recruit someone; the going pay rate; should I offer a share of any future profits; and, most importantly, establishing myself as the sole copy right holder? Basically, I want to do this in a professional way, and minimize the risk of someone "stealing" my idea, or taking control of it in the future. Is this something that would require legal counsel to come up with a contract....or can I cover my ass through a basic "contract labor" agreement? Opinions welcomed. 03:18, 30 June 2011 (UTC)

Is this an application you've already developed and just need to port to the Android platform ? Or is it just an idea ? If so, it may or may not be possible to code it. You might want to run it by a programmer you trust to see if it's possible, before hiring somebody to do it. StuRat (talk) 03:49, 30 June 2011 (UTC)

Here are some ideas:

• Find some Android development online communities/forums, create a posting that you will pay for somebody to write an app for you. Give details, don't be vague. Check their prior projects.
• Go to a local college Computer Science department, and tell them you would like to create a contest and educational opportunity for students.
• Find a few (small) apps in the Android app store, go to the websites of the authors, and ask if they would be interested in writing an app for you.

Good luck.TheGrimme (talk) 13:31, 30 June 2011 (UTC)

There are companies that develop and promote phone app ideas, such as IDC Projects. -- kainaw™ 13:42, 30 June 2011 (UTC)

Phone apps, business side

How do developers of phone apps get compensated ? StuRat (talk) 03:57, 30 June 2011 (UTC)

They probably get paid by the companies which employ them to write their code or come up with ideas. Or are you referring to something more intricate, like compensation based on the volume of sales of a particular piece of software? I was this close to writing something like by bank transfer. --Ouro (blah blah) 08:41, 30 June 2011 (UTC)

If by "developers" you mean the organisation (company) that creates and publishes an app, are several ways:

• paid downloads (an end user pays to download and install the app); its common to have a limited free edition, and a more fully-featured paid edition (or the free edition is trialware)
• ad supported (both Apple and Google have ad networks that share revenue with apps that host their ads)
• affinity or revenue sharing - for things like shopping or ticket booking or hotel finding, the app developer has some agreement with the network that's actually selling the product, and they share some of the revenue
• subscription (for something like a MMORPG)

There are also several classes of app which wouldn't expect to yield revenue themselves:

• where the app is an adjunct of a larger system (so, for example, if I create a corporate groupware system, I might have an iPhone and Android app for it, but I make the money off the groupware server licence)
• where the app is a promotional item

If by "developers" you really mean those who create the app, assuming they're not publishing it themselves, then it's just the same as other for-hire coders, designers, and artists. -- Finlay McWalter ☻ Talk 08:45, 30 June 2011 (UTC)

Actually, I do mean independent developers that publish apps themselves. Is there some arrangement (like calling 976 numbers) where the phone bill includes those fees, and they are then passed on to the developers, or must every app developer make their own billing arrangements with customers ? StuRat (talk) 13:40, 30 June 2011 (UTC)

The Apple App-Store and the Android Market act as a marketplace for those people; they collect the money, take a (large) cut, aggregate the result, and send the developer what's left. I honestly don't know about where VAT / sales tax is collected. Many Android phones allow loading of apps by other means ("sideloading"), and both Android phones and iPhones can be jailbroken (so apps can be installed from anywhere) but selling an app in such a case (where the app-store's usual protections aren't available) without it being copied for free is difficult. -- Finlay McWalter ☻ Talk 13:48, 30 June 2011 (UTC)

I see. So how much is the developer's cut ? StuRat (talk) 13:50, 30 June 2011 (UTC)

For Android Market the developer gets 70% (ref). -- Finlay McWalter ☻ Talk 13:52, 30 June 2011 (UTC)

App Store (iOS) says it's the same percentage (but Apple also charges a fee for signing apps, and I think there's a fee for them reviewing your app before they'll put it in the app store). -- Finlay McWalter ☻ Talk 13:55, 30 June 2011 (UTC)

Thanks:

1) Do apps bill for a one-time purchase, a monthly rental, or per use ?

2) What ranges of prices are there ?

3) How are (free and non-free) app updates/upgrades handled ? StuRat (talk) 14:00, 30 June 2011 (UTC)

1. One time. But apps can do "in app billing" (which is where the user performs a transaction using the app, to see "buy" a digital good like a magic sword or a music track) - see [1]
2. Android's ranges are here. The bottom of the range is essentially determined at the point at which it's cost-effective for Google to make a credit-card transaction.
3. In Android, free is free. If I understand iOS App Store correctly, free apps still have to pay to be signed and reviewed. Apple's info about their App Store distribution is here.

-- Finlay McWalter ☻ Talk 14:08, 30 June 2011 (UTC)

Is that in addition to the $99 fee you pay for the iOS SDK/join the developer program [2]? Note that the Android marketplace link seems to suggest they collect sales tax or GST/VAT in some countries. Nil Einne (talk) 18:57, 30 June 2011 (UTC)

Thanks all. StuRat (talk) 14:28, 2 July 2011 (UTC)

Source of online topographic map

Does anyone know where this map is coming from: http://www.startribune.com/newsgraphics/124520694.html

It's a detailed topographic map. If you zoom in far enough, it shows individual house numbers, decks and sheds. Far better than other "free" online maps.

Samw (talk) 03:34, 30 June 2011 (UTC)

Do you mean the outlines of houses and garages ? That's all I see, not house numbers, sheds, and decks; but perhaps the level of detail varies by location. StuRat (talk) 03:43, 30 June 2011 (UTC)

Hmm, it looks like American cities have restricted info. Try Vancouver or Toronto. Samw (talk) 15:32, 30 June 2011 (UTC)

There's a logo in the bottom-right, that of GIS company ESRI. THe underlying topographic info will likely be a general topo dataset (like Shuttle Radar Topography Mission or something from USGS) that's been rendered with ESRI's map engine. With enough skill with GIS tools its possible to create something of comparable quality - consider File:Antelope Island State Park Map.jpg for example, created with ESRI's ArcGIS. -- Finlay McWalter ☻ Talk 08:53, 30 June 2011 (UTC)

Sorry I didn't notice the obvious ESRI logo. Yes, their website has the equivalent top maps. Hopefully that is permanent as this is the best "free" top map I've seen on the web. Thanks! Samw (talk) 15:32, 30 June 2011 (UTC)

As to the other layers, most developed countries are covered by several GIS layer providers who sell layers for buildings, electrical connections, water pipes, roads, sewerage, hydrology, rainfall, flood risk, fire risk, crime level, population, and so forth. Subscriptions to these services are often fairly expensive. It looks as if the Star Tribune has such a subscription, and employs (or perhaps subcontracts) someone with sufficient skills to make something informative and attractive out of the complex datasets. -- Finlay McWalter ☻ Talk 10:31, 30 June 2011 (UTC)

You don't have to go far out of the larger cities, to lose the building detail. eg: the building detail for Paris stops just outside the Boulevard Périphérique and the detail around New York City stops just past Newark Liberty Airport. Astronaut (talk) 15:18, 30 June 2011 (UTC)

I wonder how they got that level of detail. If could be computer generated from satellite images, I supposes, but I'd expect more mistakes, then. Doing the whole thing by hand would be prohibitively expensive. Perhaps it's computer generated and then reviewed by humans, to catch the blatant mistakes. StuRat (talk) 17:43, 30 June 2011 (UTC)

Thanks everyone for the quick response! Samw (talk) 15:32, 30 June 2011 (UTC)

A lot of USGS maps (that are still useful) are very old, and were in fact made by humans. ¦ Reisio (talk) 18:27, 30 June 2011 (UTC)

Yes, but I don't think any of those showed decks and swimming pools for each house. StuRat (talk) 22:47, 30 June 2011 (UTC)

Processor cloud

Anyone know of an online service that offers the user/subscriber access to multiple processors (thousands) presumably by assigning each processor a unique address just as memory addresses are assigned in order to support programs that have subroutines which are intended to run in parallel and not sequentially? --DeeperQA (talk) 10:28, 30 June 2011 (UTC)

I don't know of any. Sounds like you want to rent a data center! What theoretical use do you use for it? Trying to run Crysis? :) --24.249.59.89 (talk) 14:49, 30 June 2011 (UTC)

It's not practical to build computers with that architecture. The problem is that, when you have a whole lot of processors talking to one uniform pool of memory, performance goes down and cache coherence becomes a nightmare. This is why non-uniform memory access is being developed. Paul (Stansifer) 17:12, 30 June 2011 (UTC)

Sorry guys (or girls), I need responses from those experienced enough to know that server nodes normally come with sufficient storage for status, data and results and can incorporate fanless PCs, signal or video processors or even microcontrollers in a Beowulf's configuration that have easily expandable memory via SD cards or flash drives and which emphasize processing power rather than file space and know the universities or research computing facilities that offer up such systems for use by the public. --DeeperQA (talk) 01:16, 1 July 2011 (UTC)

In commercially available massively-parallel systems, CPUs do not have unique addresses. Network interfaces have unique addresses. We usually use the Internet Protocol to uniquely identify and communicate with a compute-node. We can construct an n-to-m mapping between n network-interfaces and m CPUs, facilitated by one or more instances of an operating system. If you don't like this scheme, and want to use a different addressing-scheme to access thousands of CPUs, you may need to pursue exotic computer architectures (that are not easily/commercially available). You can start by reading classifications of parallel computers. For example, the now-defunct SiCortex vector-computers, or the IBM Blue Gene computers used different protocols and methods to address compute-node function units. As Paul Stansifer has correctly pointed out, for most problems, esoteric vector architectures are very inefficient. Linear arrays scale ... linearly. Many other algorithms that are necessary for communication scale as the square of the number of nodes; see, for example, routing topologies. If you think you don't need these algorithms, reconsider how you will communicate unidirectionally, let alone bidirectionally, with your compute-nodes.

If you simply want to pretend that you have a linear array of CPUs, your best bet is to construct a simple software that abstracts a list of IP addresses as a simple array. Nimur (talk) 19:50, 1 July 2011 (UTC)

Harvesting HDD from an external enclosure

I've noticed that when some external retail hard drives from a manufacturer goes on sale, the cost is actually less expensive than their new bare internal OEM drive of the same capacity. Is there any issue of disassembling the external case to liberate the bare drive? They aren't hard soldered to the USB bridge, are they? --24.249.59.89 (talk) 14:43, 30 June 2011 (UTC)

I've never encountered one that was. Every one I've opened has been a run of the mill desktop or laptop drive, with a conventional PATA or SATA connector, and a USB interface chip. -- Finlay McWalter ☻ Talk 14:46, 30 June 2011 (UTC)

Same here, they've all been attached with the same SATA or IDE connector. Can be kind of a bear to break into though sometimes. RxS (talk) 21:06, 30 June 2011 (UTC)

Native USB drives exist ([3][4]), so you should check before buying. With the increasing popularity of USB hard drives I'd think that this would become increasingly common.

Also, opening the enclosure will void your warranty, so it's not financially prudent unless you value the warranty less than the price difference. Or, I suppose, if you're confident that you can reassemble the enclosure well enough to fool the manufacturer. -- BenRG (talk) 23:57, 30 June 2011 (UTC)

projected and non -projected visuals

please what are the differences between projected visuals and non projected visuals — Preceding unsigned comment added by Kofibarwuah (talk • contribs) 14:51, 30 June 2011 (UTC)

I'm guessing this is in an educational context. If so, projected visuals are those which are, err, projected, such as overhead projectors, slide projectors, digital projectors. By a process of elimination, I guess non projected visuals are such things as handouts, books and objects best appreciated at desk by individuals rather than viewed en masse by the class. --Tagishsimon (talk) 15:06, 30 June 2011 (UTC)

I'm guessing you already know what they are, and are asking about the difference in quality, between, say, a projection TV and a non-projection TV, such as LCD or plasma. Here are some diffs:

1) While the projection could actually be brighter, if projected onto a small enough screen, it's typically dimmer, requiring a darkened room to view it.

2) A projected image can be distorted, depending on the location of the projector and shape of the screen. Similar distortions were also possible with a CRT TV (such as a the keystone effect), but aren't with newer types.

3) If the projector does the colors separately, you also have potential for colors to be misaligned. Again, this could happen with a CRT, too.

4) The projected image may be out of focus.

So, overall, a projected image is inferior, and is only used when the size of the screen is too large for other methods. StuRat (talk) 17:33, 30 June 2011 (UTC)

Finding out why my laptop rebooted

Hey guys, I was wondering if there was a way to find out why my Windows Vista laptop rebooted itself during the night. I left it on so I could download some files overnight, but when I woke up this morning, I found that nothing was going on. My download manager was closed (the files hadn't downloaded either), and I checked on Task Manager to find that the computer had restarted itself around 3:33 AM. Is there any way I can find a reason for this reboot? I first suspected it may have been overheating, but usually when it overheats it simply shuts down, not restarts. I've checked Event Viewer but haven't found anything conclusive (or maybe I'm reading it wrong). Any ideas? Thanks. 141.153.214.125 (talk) 17:32, 30 June 2011 (UTC)

I know you've said you've looked, but Event Viewer is likely where you need to look. The "System" log will at least show startup events so you'll see what time it started up. Look out for any Windows Updates as possibly you have your settings set to automatically install (and reboot). Or look out for a "WIndows recovered from an unexpected shutdown" which basically means a blue screen happened (it could also be caused by just turning off the power, but obviously you didn't do that). Actually, possibly you had a slight powercut maybe, enough for the computer to reboot. Sorry I'm not sure I'm being much help, but System and Application logs in Event Viewer are the two which will give you the clues.  ZX81  ^talk 18:27, 30 June 2011 (UTC)

Checking all nodes of the Event Viewer is probably the best route. I would would also disable the feature where Windows automatically restarts the computer in the event of a fatal error, which might be happening. See this article on how to disable it in Windows 7, Vista, and XP. Additionally, you might find more help in the Computing section of the reference desk. TheGrimme (talk) 20:38, 30 June 2011 (UTC)

A couple of my machines have whinged at me to be rebooted over the last 24ish hours, having downloaded an MS security patch. It's possible your reboot was caused by that. I'm not sure what forensics are available in that department - the update history provides date-stamps but not time-stamps for each of the updates applied. --Tagishsimon (talk) 21:10, 30 June 2011 (UTC)

I was just going to say "security patch", too, because Windows machines are configured by default to restart after automatically downloading certain types of patches from Windows Update in the middle of the night; and Microsoft has issued several patches over the last week. If you go to the Control Panel and type "Windows Update" (don't hit Enter!) in the "Search Control Panel" field, you'll see an item called "Turn automatic updating on or off", if you are interested. Comet Tuttle (talk) 22:03, 30 June 2011 (UTC)

firefox/ fedora 7 not behaving

Hi, I'm currently using Fedora 4, and I recently got a copy of the Linux Fedora 7 dvd/ live cd, and had a go at using the live cd. It doesn't recognise my printer, and firefox crashes every time I right click, whether on a link, or on a blank part of the page. My current (Fed 4) set up is a nuisance, because it doesn't recognise my printer, evolution email doesn't delete messages properly, it won't copy to cdrom, won't do most music and video apps, and firefox is highly sensitive to javascript content (wikipedia crashes with javascript on if I try to edit). Further, when I turn on the computer, it will only recognise the modem about 50% of the time, otherwise giving me a "SIOCSIFNETMASK" message saying the modem is unreachable. Nevertheless, I can live without a printer, as I hardly ever use it, I can reboot the system and it will recognise the modem second time round, and the other problems I can put up with. I want to upgrade to get a slick system that works in all these details, but it looks as though things are getting worse, and I'm not sure about taking any risks.

Firstly, if I upgrade, will Linux install if I change my mind and try to downgrade (putting Fedora 4 over a later version)? Secondly, does anyone know if the firefox crash (and printer woes) might only pertain to the live cd version I used (and not be found on the full install)? Finally, what's happening here? Surely someone could have tested Firefox and found it was just crashing all the time. Does it get better with later releases after Fedora 7, because I'm finding them hard to come by (not available in libraries and bookstores)? Thanks, It's been emotional (talk) 17:36, 30 June 2011 (UTC)

How do you have internet access? The latest releases of Fedora are comparably easily downloadable. Is your printer less than four years old? Fedora 7 stems from 2007, so it's not that old, and yet four years in computer science almost seems like forever. My first recommendation is to download a newer version of Fedora if possible and try to install that. Oh, what are the specs of the computer you are using? Cheers, Ouro (blah blah) 21:25, 30 June 2011 (UTC)

The live disks are not dependable. A smudge or scratch easily causes a situation where it boots, but there are many issues while trying to use the computer. Further, the live disks is a "first try". Usually, the first thing you do after installing from a live disk is install all the updates. After installing Fedora 15 (three days after the release), I had a good hour of updating. If there are bugs in the printer service (probably Hal in Fedora 7) or Firefox (version 2 in Fedora 7 if I remember correctly), they were likely fixed in updates, which will be difficult to get now. You are much better off getting Fedora 15. But, you mention a modem. If your computer is extremely old, I suggest getting a live disk with a very simple video display, like the LXDE version. Gnome and KDE will really task your hardware if your computer is old. -- kainaw™ 02:09, 1 July 2011 (UTC)

Thanks folks. The computer is 512MB, ~60gb hard drive, about 1 or 2 GHz Pentium (I think) dating from early 2005. I think the printer was from the same time. I use broadband, but am not keen on downloading an os because it would take ages, and one of the extra problems is my computer won't allow me to install things. I've tried many times, and even when I log in as root, nothing happens. I was using a live disk to check out Fedora 7, but don't want to install from a live disk (I also have the dvd) because it will wipe my system. Can I get an update with LXDE to install (I don't fancy relying on a live disk forever)? Why are Firefox updates hard to find? I'm hoping if I do upgrade, it won't be so hard to install updates with the new system. It's been emotional (talk) 09:39, 1 July 2011 (UTC)

You have some serious problems. It's not your computer that prevents you from installing things, it's Fedora 4. This of course is now an antique. If you have an external hard drive, how about copying all the files you want (including your mail, etc) to this hard drive, installing a new (lean) distro (something like Fuduntu, antiX, CrunchBang, perhaps), and then copying back? Updating Firefox--possibly called IceCat, IceWeasel, or something else--should then be simple. Tama1988 (talk) 10:16, 1 July 2011 (UTC)

Thanks for the advice. I have all the files I need copied to usb and the internet (I use gmail as a backup for critical stuff, in case a housefire destroys the lot at my end - better safe than sorry). I'm keen to stick with Fedora, since it's easy to get copies of the dvd's and I don't know where to find the leaner distros on dvd (downloading a whole os would be new to me, and I'd rather put up with a bit of irritation than spend the time). I just really need to know if anyone can tell me whether I can easily go back to Fedora 4, then I could take the risk. On the other hand, if you can tell me of a book with a good dvd in the back for a leaner distro, with no major bugs, suitable for my system, I'd be keen to find out, especially if it can keep my files from Fedora, since it would be finnicky making sure I've got every last detail copied. It's been emotional (talk) 11:08, 1 July 2011 (UTC)

Difference between computers and humans

For me it's clear that routine tasks are performed better by computers, but what other differences are between human and computer processing? Wikiweek (talk) 21:02, 30 June 2011 (UTC)

If you're not familiar with it, a read of Chinese room might be instructive, as might links therefrom. --Tagishsimon (talk) 21:05, 30 June 2011 (UTC)

I don't see how the Chinese room argument can "instruct" anyone in anything but Searle's opinion. Searle believes that there is a quality that can reasonably be called "understanding", that it is possessed by humans, and that human-like behavior in an object is not sufficient to conclude that it has understanding. He believes that, no question; so what? It's not like the Chinese room argument justifies it in any way. It only appears to justify it if you were predisposed to believe it anyway. It's no more useful than other philosophers' foolish proofs of the existence of God. -- BenRG (talk) 04:48, 1 July 2011 (UTC)

Okay, I'll bite. It is a very material argument in the debate about strong versus weak artificial intelligence. And that debate would seem close to the heart of the OPs question. To say "it's just his opinion, so what" is a self-limiting view which says more about your unwillingness to think about the issue, than it says about the issue. The debate has been going on for thirty of forty years amongst experts in the field; Searle's contribution being a not insignificant plank thereof. You'll forgive me if I go with the body of experts rather than a snotty and dismissive "so what" response from a random kid on a message board. --Tagishsimon (talk) 10:17, 1 July 2011 (UTC)

I don't believe BenRG is a kid and I don't believe the Chinese room says something about how humans/computers process information.88.14.198.240 (talk) 12:57, 1 July 2011 (UTC)

Bio-inspired computing and its links might also be interesting. Note: You're incorrect about your first statement unless you really narrow down what "routine" means. If you mean "adding two integers", then yes; but a "routine" task for a human might be "recognizing the emotion that your mother is currently experiencing, in under one second", and humans currently are far superior to computers at that one. Comet Tuttle (talk) 21:58, 30 June 2011 (UTC)

The Chinese Room is a purely philosophical argument; it says nothing about any material differences between human and computer processing. In fact that's very much the entire point of the Chinese room argument: to think about two different ways of arriving at exactly the same result. I agree with BenRG that it's irrelevant to the question. APL (talk) 04:04, 6 July 2011 (UTC)

You might also check out Hubert Dreyfus's classic What Computers Can't Do. It's a bit dated but it serves as a nice introduction to thinking about the difference between human and machine cognition. There are very significant differences and as Comet Tuttle points out, "routine tasks" does not begin to address them. --Mr.98 (talk) 01:44, 1 July 2011 (UTC)

This book should have been called: "What Logical Rule-Based Systems using Variables but without Learning Can’t Do." Consider, however, that modern programs (which are able to learn) are approaching human mental abilities one step at a time. 88.14.198.240 (talk) 11:44, 1 July 2011 (UTC)

Dreyfus (and Searle, for that matter) would dispute that you can approach human mental abilities incrementally, I believe. Searle in particular does not see human mental abilities as just scaled up computing. (Granted, I don't agree with either of them, but it's no response to say, "oh, we're getting there," to people who believe that machine processing and human thinking are fundamentally different. The challenge for them is to really explain why human thinking shouldn't be fundamentally algorithmic at its base, without an appeal to something supernatural.) --Mr.98 (talk) 14:22, 3 July 2011 (UTC)

OK, we are not approaching what humans are, but what humans do. Indeed, computers are emulating human capabilities for sure, in the same sense that a wheel emulates legs (not being legs, but fulfilling the function of locomotion in a different way). If a complex computer could be conscious of itself (or is it already time to call it himself?) is a different topic. 88.14.198.240 (talk) 14:38, 3 July 2011 (UTC)

Google search for "sex"

Does anybody have a clue why a Google search for "sex" brings up a toplink to Sex (book) rather than sex? --84.44.231.244 (talk) 22:32, 30 June 2011 (UTC)

Google does not just list the most relevant search result. It also tries to adapt to you, and to adapt to results that are up-to-date (which is probably the case of this book). Wikiweek (talk) 22:37, 30 June 2011 (UTC)

On a somewhat related note, there was actually an interesting piece on Democracy Now! a few weeks ago, regarding the personalization of search engines, and how it creates an "echo chamber" that reinforces our biases, rather than leading us to new information. ~ Mesoderm (talk) 22:42, 30 June 2011 (UTC)

I have the same problem! Fuck! Google must have somehow come to the conclusion that I'm an educated person :( :( How do I set it straight? 188.29.114.156 (talk) 22:59, 30 June 2011 (UTC)

To convince Google that you are less educated than the average is a daunting task. Start by not writing full sentences with proper grammar. 88.14.198.240 (talk) 11:56, 1 July 2011 (UTC)

Private browsing modus should tackle the problem. In Firefox go to Tools > Start Private Browsing. Wikiweek (talk) 23:06, 30 June 2011 (UTC)

Damn, it still gives sex book. At least it hasn't gone as far as putting 'The Mathematics of Sex' as the first result for me yet! ;-) Dmcq (talk) 23:12, 30 June 2011 (UTC)

Under private browsing, it also gives Sex (book) for me, probably because it's up-to-date, and it's followed by the Massachusetts sex register directory, since Google also geo-locates, to offer us more relevant search results. Wikiweek (talk) 23:18, 30 June 2011 (UTC)

And this? http://www.google.com/search?q=sex ¦ Reisio (talk) 01:29, 1 July 2011 (UTC)

I don't see what the problem is. You need to refine your search. Which sex? Do you want medical advice or porn? What are you actually searching for?--Shantavira|^{feed me} 07:38, 1 July 2011 (UTC)

You cannot expect that a search engine outputs good results with one word input. Just try the same query with a female human to see how poor the input is. 88.14.198.240 (talk) 11:48, 1 July 2011 (UTC)

For me and Google.com (not .co.nz), the first search result for 'women' is woman which seems fair enough. The second 'iVillage - the daily destination for women, with an active women's community, horoscopes, health and pregnancy information, message boards' which is also not unreasonable. The third result is 'Top 99 Most Desirable Women of 2011 - AskMen' which also seems reasonable considering the earlier results. For 'woman' we get the same first result. The second result is [5] 'Woman definition, the female human being'. The third result is 'Enjoy Woman magazine, on sale every Tuesday, packed full of celebrity gossip, real life stories, fashion, beauty, healthy recipes, diet & relationship' which is I guess a little strange. google.co.nz is slightly stranger and the ad results lean to one obvious direction.

BTW the OP could emigrate to NZ if they are unhappy with the results for 'sex'. For google.co.nz my first result is the NSFW and blacklisted www.pornhub.com and there a bunch more similar results compared to the .com which is filled with sex offender registers.

Nil Einne (talk) 12:10, 1 July 2011 (UTC)

If I Google 'Sex', (not something that I would normally do of course), the first item is a lead to "Porn Hub", so I MIGHT look again after all!--85.211.228.45 (talk) 13:21, 6 July 2011 (UTC)

July 1

svn problem

Hi. I am trying to get to grips with svn but have a peculiar problem:

$ svn diff -r 52 BACCO
Index: BACCO/inst/doc/both_papers.Rnw
===================================================================
[snip]

that is, it works as desired. But watch:

$ svn diff -r 51 BACCO
svn: Unable to find repository location for 'BACCO' in revision 51
$ 

that is, it seems to have forgotten where the repository is. Why might this be? Robinh (talk) 01:32, 1 July 2011 (UTC)

Probably that part of the tree was created in r52 and therefore did not exist in r51. You can do an "svn log -v http://your/svn/tree" (the top of the tree) to see when BACCO was created. --Sean 14:38, 1 July 2011 (UTC)

yes, that's it! Looks like I did indeed create BACCO at revision 52. Which is certainly not my recollection, but I guess memory is less reliable than svn.

Resolved

Robinh (talk) 20:11, 3 July 2011 (UTC)

Compiling PureDarwin

After downloading the source for PureDarwin and applying pd_fetch and pd_thin I tried to use pd_setup but it runs without a dialogue and goes back to user@home:$ (I did use sudo like I was supposed to). There was no change, no files created, nothing happened. What gives? --Melab±1 ☎ 05:06, 1 July 2011 (UTC)

http://webchat.freenode.net/?nick=compileProblem&channels=#puredarwin ¦ Reisio (talk) 06:54, 1 July 2011 (UTC)

Full form of 'i' in 'intel i series of processors'

What does the letter 'i' in 'intel's i series of processors' stands for?? I've searched over the internet bt unable to get any useful answers... So i'm at wiki's door to know the answer.. Plz explain if anybody knows abt it.. Thank you in advance --Simranjeet2310 (talk) 13:22, 1 July 2011 (UTC)

In all the Intel related articles I cared to look at (see Template:Intel processors for a convenient start point), and external sources such as: here, here and here, I couldn't find an explanation. However, if I was to guess, I suppose the i might stand for "intel". Astronaut (talk) 15:28, 1 July 2011 (UTC)

You can be sure that it has no official expansion, since, if it did, it would be mentioned in the promotional materials. But it's easy to guess what was going through the mind of the marketer that invented it. The i in the Intel logo has always been lower case. They've used the i prefix in chip names before, as far back as 1981 with the iAPX 432 and later with the i960, i860 and i486. (iAPX allegedly stands for "intel Advanced Processor arΧitecture".) And Apple has recently had success marketing their products with iNames, which is all the more reason for Intel to revive the custom. -- BenRG (talk) 23:24, 1 July 2011 (UTC)

But as far i'm concerned i guess i stands for 'itanium' as the letter 'p' in earlier processors stands for 'pentium'... any suggestions???? coz m still not sure....--Simranjeet2310 (talk) 11:45, 2 July 2011 (UTC)

I'm 99.999% sure it isn't Itanium as that's a completely different processor architecture so it wouldn't really make any sense. I believe it's just Intel like Astronaut suggested. 78.25.234.1 (talk) 03:06, 3 July 2011 (UTC)

According to Intel rep Bill Calder on this page (see comments), it actually doesn't stand for anything in particular -- the name was just used in hopes of being memorable to consumers. Looie496 (talk) 03:29, 3 July 2011 (UTC)

Thnku vry mch frnds... i appreciate ur help... thnx for being dere... :) --Simranjeet2310 (talk) 12:21, 3 July 2011 (UTC)

Firefox font messed up?

Picture of the offense!

Hey guys, anyone know what's going on with my laptop/Firefox at the moment? Happened today and I can't think of anything I've done that would have caused it. As you can see, all the font seems bold. On other sites like Facebook the font seems small and somewhat fuzzy, but most sites show the font as bold. Firefox's font settings are all normal. Any help would be much appreciated :) Regards, --—Cyclonenim | Chat  19:30, 1 July 2011 (UTC)

It could be that one or more of your font files has become corrupted. Have you noticed whether sites which use sans-serif fonts display differently from ones with serif fonts? You could also check whether the same problem occurs in other browsers, and whether text in other applications (like office software or maybe even things like menus) looks weird as well. You could test by changing Firefox's default font settings to something unusual and see if you lose the bolding.

If you're using Windows, you could try replacing the copies of Microsoft Core Fonts on your laptop with fresh files, perhaps starting with Arial and Times New Roman, which are the standard fall-back fonts. Getting hold of the font files may be a bit tricky; if you have a OS disk, you can copy them from it (some Windows 7 instructions towards the bottom of this page). There are also some external links in the MCF article, although I can't vouch for their authenticity. --Kateshortforbob _talk 23:10, 2 July 2011 (UTC)

I find it unlikely that my font sets have been corrupted because everything appears fine on other browsers; to me it seems like a firefox problem. If I start it in safe mode, the problem disappears leading me to believe it may be an add-on problem. However, if I disable all my add-ons in normal mode, the problem persists. I am baffled. Regards, --—Cyclonenim | Chat  13:13, 3 July 2011 (UTC)

Hrrm, that is weird. Does the problem persist if you create a new profile in FF (Run > firefox -p)? Other things I would check (if you haven't done so already) would be:

• Character encoding changed to something strange
• "Allow pages to choose their own fonts.." in Preferences >Content >Fonts >Advanced unchecked?
• about:config font preferences, such as font.language.group, all the font settings for whatever language code you use (probably Western?) and any user-defined font settings
• contents of the usercontent.css file, if you have one.

This post seems to describe a not-entirely dissimilar problem (using FF5). I may be worth trying some of the suggestions there.--Kateshortforbob _talk 16:44, 3 July 2011 (UTC)

Recommended antivirus/antimalware

I was just curious about which antivirus/antimalware programs you guys recommend/use. Thanks. 141.153.214.125 (talk) 19:48, 1 July 2011 (UTC)

There's a list of antivirus programs available here. I like Avira AvrillirvA (talk) 20:55, 1 July 2011 (UTC)

Avira, Microsoft Security Essentials, Malwarebytes' Anti-Malware, Spybot – Search & Destroy. See also Wikipedia:Reference desk/Computing/Viruses. ---— Gadget850 (Ed) ^talk 20:54, 1 July 2011 (UTC)

Back in the dark days (when I was a Windows user) I used AVG free and Malwarebytes' Anti-Malware. Malwarebytes is really great, but AVG makes things really slow. But now I use Linux so I have no need for any of them. --T H F S W (T · C · E) 21:14, 1 July 2011 (UTC)

I second that. Switching to Linux is the best "anti-virus", but if you have to use Windows for some reason, then AVG works and is free (it's been a few years since I last used Windows though, so I can't speak to how fast/slow AVG is nowadays). ~ Mesoderm (talk) 21:25, 1 July 2011 (UTC)

I went up against Zeus recently and AVG was of no use— it got attacked and would not run. I used all four in my list to finally kill it. MSE is free, surprisingly light and is getting very good ratings. ---— Gadget850 (Ed) ^talk 22:35, 1 July 2011 (UTC)

It depends on what PC your running it on. I've found Avast! is good for most PCs, but tends to bog down older machines. Currently, I use ClamWin, as they are the only antivirus program I've found that runs on Windows Server OSes without a paid license. ^Avic_ennasis @ 09:55, 30 Sivan 5771 / 2 July 2011 (UTC)

I have MSE running on Windows 2008 Server. ---— Gadget850 (Ed) ^talk 20:41, 2 July 2011 (UTC)

Perhaps I forgot the "non-microsoft" part. :-) ^Avic_ennasis @ 03:48, 1 Tamuz 5771 / 3 July 2011 (UTC)

I have Avast! and SpywareBlaster installed. I also ocassionally scan with MalwareBytes, SuperAntiSpyware, and Spybot. 92.28.244.187 (talk) 19:42, 4 July 2011 (UTC)

userscript

I have an example greasemonkey script as follows;

document.title = document.title + '1234'

This takes the title of a page and appends "1234" to the end. It works on every site except Twitter since they changed to their new javascript heavy version. How can I make it work on Twitter? 82.43.90.27 (talk) 20:51, 1 July 2011 (UTC)

July 2

Windows 7 Backup disks

Hi, sorry to be asking so many questions in such a little time, but I recently got a new laptop and want to ensure that it'll last me a while. It didn't come with any W7 back up disks, so if I were to follow the instructions from [6] and [7], would I be set on recovery disks? I plan to make two, one with everything that's already preloaded on it, and another after I've installed some of my own programs on it (i.e. antivirus, word processing, browser, etc). Would this be a good idea or am I just being overly meticulous? Thanks in advance. 141.153.214.125 (talk) 05:13, 2 July 2011 (UTC)

If it was me, I would have only bought from a manufacturer who supplies the disks either by default or as an extra cost (~$10) option. In your situation, having already received my new PC, I would be tempted to call the manufacturers and demand they send me the relevant disks. It probably wouldn't get me anywhere, but it would emphasise the point that (some) customers think a means to reinstall the OS is pretty damn important. After all, you don't buy a PC and then have to rush out to buy a power cord, why would they make you do something similar for the software installed on it.

A more practical answer might be to examine the instructions and manuals carefully, and to have a good look on the start menu (particularly those menu options you might never visit). What you are looking for is a means to create your own recovery disks. Astronaut (talk) 09:48, 2 July 2011 (UTC)

Many OEMs now have an application under All Programs to create the disks. Doing PC repairs, I find that most folks have no clue where their disks are anyway. At my last employer we stopped shipping hard copy manuals, just a startup guid; no one read the manuals and when they needed to, they couldn't find them. ---— Gadget850 (Ed) ^talk 17:06, 2 July 2011 (UTC)

Non google / bing search engines by marketshare?

Hi, I'm sure this question has been asked before.

Nowadays, almost every damn "search engine" seems to be nothing more than a front-end of google or bing. Yahoo - gone. Altavista - gone. Lycos - gone. Can someone please point me to a list of the biggest non-google / bing search engines by marketshare? (Please do not include google / bing front ends, obviously!). Eliyohub (talk) 11:32, 2 July 2011 (UTC)

A quick search reveals a bit. See also Wolfram Alpha, as I didn't see it at first glance. --Ouro (blah blah) 05:25, 3 July 2011 (UTC)

I'm guessing you also wish to exclude search engines which only work within their own site, like Wikipedia and IMDB ? StuRat (talk) 06:29, 3 July 2011 (UTC)

Laptop battery with built-in DC socket

I have an Acer Aspire One "Happy" netbook, and am wondering if there is such a thing as a replacement battery, by Acer or otherwise, that has its own DC socket, that is, the laptop charger would plug into the back of the battery. Any ideas? Thanks.--Leon (talk) 12:47, 2 July 2011 (UTC)

This Google search on 'Acer Aspire One Happy charger' brings up a lot of links of palces to get chargers for the Acer Aspire One 'Happy'. Good luck. --KägeTorä - (影虎) (TALK) 13:23, 2 July 2011 (UTC)

Yes, except I want a replacement battery with its own DC socket to connect to the mains. The reason I want such a device is that a common point of failure on laptops is the DC socket on the motherboard, so I'd like to circumvent this weakness by a more cheaply-replaceable device, such as battery, or even dummy battery, that accepted DC in.--Leon (talk) 14:11, 2 July 2011 (UTC)

That's a good idea you've got there, but note that, to plug the laptop in on the back, which is probably best, the battery would then need to extend to the back of the laptop. An alternative may be to have two or more batteries, and then charge each separately with it's own charging cradle, while out of the laptop. This would involve swapping the batteries quite often, but has the additional advantage of not having your laptop attached to the wall by a cord, thus increasing it's portability. (Of course, if you need to have it attached to the wall for some other reason, like an Internet connection, then this point is moot.) StuRat (talk) 14:25, 2 July 2011 (UTC)

In the case of my laptop, the battery is already so located! And to adapt it to fit a DC jack, purely in terms of space, would only require it to increase slightly in size. But this is digression: does anyone know if such a device exists?--Leon (talk) 14:35, 2 July 2011 (UTC)

Not a laptop, but I do have a portable DVD player with that arrangement. StuRat (talk) 16:10, 2 July 2011 (UTC)

I'm curious as to why your edit history for this question lacks links to the section, unlike mine:

(cur | prev) 16:11, July 2, 2011 StuRat (talk | contribs) (77,754 bytes) (→Laptop battery with built-in DC socket) (undo)
(cur | prev) 14:35, July 2, 2011 Star trooper man (talk | contribs) (77,593 bytes) (Laptop battery with built-in DC socket - r) (undo)

How do you reply ? And do you manually type in an edit summary ? StuRat (talk) 16:17, 2 July 2011 (UTC)

Erm, I do manually type in edit summaries...don't most people? To reply, I click "edit" at the right of the section heading - is there another way?--Leon (talk) 18:03, 2 July 2011 (UTC)

Clicking the "edit" next to the section heading pre-fills the edit summary with the section header between C-style comments. The comments cause a link to appear in the page history. Remove the comment markers and you lose your link. Astronaut (talk) 20:35, 2 July 2011 (UTC)

Yes, that's probably it, were you removing the "/*" and "*/" from the edit comment ? There is another way to edit, by picking "Edit" at the top of the page to edit the entire page at once. I certainly wouldn't recommend this here, though, as edit conflicts are quite likely, and there will be no automated edit summary and thus no section link. StuRat (talk) 22:18, 2 July 2011 (UTC)

I was removing those marks - I'll stop now!--Leon (talk) 08:53, 3 July 2011 (UTC)

Thanks ! StuRat (talk) 09:17, 3 July 2011 (UTC)

Printing port from laptop computer.

My laptop was recently overhauled. Did manage to retain original hard drive, with corrupted files, back to factory specs. Now, unable to print wirelessly using desktop printer. Pretty sure it is a 'Port' issue, but not sure how to fix. Main computer, which I have always share uses a 'USB...Virtual Printer port for USB' ( for a HP Photosmart 3200 series) for it's printer port option. My 'New Laptop' does not have this port as an option. Have tried most every way I can think of to add and/or configure new port. I know this is an easy fix, just not enough experience to do it & really hate to call my computer guy!! Can I get some help?? Was printing fine prior to laptop changes. -User:Toby's Info 17:15, July 2, 2011(UTC)

Reformatted for readability. ---— Gadget850 (Ed) ^talk 17:50, 2 July 2011 (UTC)

Here is the user manual.[8] Looks like the printer would have a Bluetooth adapter in the front USB port. See page 29 of the user manual for Bluetooth setup. ---— Gadget850 (Ed) ^talk 17:55, 2 July 2011 (UTC)

I'm a little confused. By "main computer" do you mean another (desktop?) PC with the printer physically connected by a USB cable? This type of connection is described on p.30 (page 33 of the PDF) of the manual and note that the 'main computer' needs to be on and printer sharing enabled for the laptop to be able to use it.

Other than that, bluetooth is just one of the ways you can connect to the printer. In all cases you will need the drivers installed on your laptop - I wouldn't be surprised if these got damaged or deleted in the overhaul. However, I notice the printer has a built-in print server - probably the best connection is by ethernet cable to the rest of your home network - see p.33 "4 Connect to a network". Astronaut (talk) 20:28, 2 July 2011 (UTC)

OP stated "unable to print wirelessly", leading me to believe he is using Bluetooth. ---— Gadget850 (Ed) ^talk 20:34, 2 July 2011 (UTC)

Even more confused now, aren't you the OP? Oh, ... and what operating system are you using? Astronaut (talk) 20:42, 2 July 2011 (UTC)

The original post had a bunch of odd markup that I reformatted; I must have added my sig without thinking. Fixed. ---— Gadget850 (Ed) ^talk 22:52, 2 July 2011 (UTC)

Oh! Thanks for the explanation. I guess we'll have to wait til Toby comes back with more information. Astronaut (talk) 12:31, 3 July 2011 (UTC)

no "advanced search"

A couple of days ago google redesigned its main page. Formerly you could click on "advanced search" there. Now you can't. If I simply enter the letter "a", or any other search terms, then on the results page I can click on "advanced search". If I want to restrict the search to a certain domain, AFAIK I need "advanced search". What is considered to be the advantage of making it unavailable from the main page? Michael Hardy (talk) 19:54, 2 July 2011 (UTC)

At the top right of the page there's a circle thing, click it and a drop down menu appears with advanced search and other things. Here is a guide on all of googles advanced search options for using without going to the advanced search page. As for why they changed it, we can only guess googles motivation for redesigning the page but there seems to be a trend across all websites for making everything look more like an ipod often at the expense of functionality. AvrillirvA (talk) 20:02, 2 July 2011 (UTC)

I found a post on the google blog giving their rationale for the changes here AvrillirvA (talk) 21:57, 2 July 2011 (UTC)

Note you don't need the advanced search to restrict the results to a certain domain. just add site:domain.name somewhere in the search. Similar with filetype (filetype:). You do need advanced for searching in a specific language or readling level I believe (and I think things like date). Nil Einne (talk) 23:19, 3 July 2011 (UTC)

So they've hidden it in a place where I would never have found it without inquiring here, and they consider that an improvement. Michael Hardy (talk) 19:24, 3 July 2011 (UTC)

What is wrong with my computer?

Hello. Can someone please tell me what is wrong with my computer and what I can do to fix it? Thanks. Here is the situation. Let's say that I do a Google search and 100 sites come up in a list. The list has all blue-colored links, so that when I click the link, I am taken directly to that particular site. Now, after I click that blue link, it changes color and becomes a purple-colored link. That helps me to keep track of which links (sites) I have already visited and which I have not. So, let's say that out of 100 sites, I only visit the first ten sites on the list today. Tomorrow, when I come back on the computer, I will see that the first ten sites are listed with purple links, and the sites numbered eleven onwards will still have blue links. So, this will remind me to start with link #11, knowing that I already visited the first ten links. The problem now is that I never get purple links any more. All links are always listed in blue, so I can't keep track of which sites I have (or have not) yet visited. Why is this? Does anyone know? And what can I do to fix this? The Google search was only one example. Another example is here on Wikipedia. Usually, the wiki-links are colored blue. When I click a wiki-link (and visit that article), the link changes from blue to purple. But, that does not work either, anymore. My links are always blue, never purple ... whether I am talking about Google search result links or wiki-links or anything else of that nature. Please help. Thanks! (Joseph A. Spadaro (talk) 23:57, 2 July 2011 (UTC))

Have you switched on private viewing? It may have been done to stop people finding out about what sites you have browsed using javascript to check the state of various links. It is a security feature. Dmcq (talk) 02:46, 3 July 2011 (UTC)

• Look in your browser settings for color settings, and check what colors are used for visited links and unvisited links.
• Links will only stay purple for as long as they're in your browser's history. Check your browser settings to see if the history duration is set too low. Check for any security programs that might be deleting the history. Or check if anyone using the computer might be regularly deleting the history. Or, as Dmcq mentioned, the Private mode of your browser may prevent any history being stored and thus prevent links turning purple. --Bavi H (talk) 03:02, 3 July 2011 (UTC)

Thanks to you both. However, I am not a computer "techie" person ... and I am not that savvy with all of this computer technical stuff. So, I barely understood a word of your responses. I have never (deliberately) made any changes to this computer, and no one at all (except me) has access to this computer. The only changes that I ever see being made are when Microsoft says that they have an (automatic) update that they are going to install. I don't know how or where to change any browser settings or any other settings (that you mentioned in the above responses). If it matters, I access the internet with Internet Explorer (9, I think) ... and my home page is AOL ... and I have Windows 7. So, can someone please tell me step-by-step exactly what I need to do to fix this problem? Thanks. Much appreciated. (Joseph A. Spadaro (talk) 14:30, 3 July 2011 (UTC))

It's not clear what is causing this problem or how to fix it. A web search turns up a bunch of other people with the same problem, but no clear solution ([9][10][11][12][13]). It may be a bug in IE9 that will eventually get fixed. The only suggestion in those threads that seemed to work was deleting the browsing history as explained here. -- BenRG (talk) 04:42, 4 July 2011 (UTC)

Thanks. I checked out that suggested link on "How to delete your browsing history in Internet Explorer 9". Again, I am somewhat confused. Would deleting your browsing history actually solve this problem? Or exacerbate it? I'd think that affirmatively deleting the browsing history just takes me right back to square one (all blue links, no purple links) ... no? The history deleting would render my computer as if I had never visited any sites at all ... correct? So, how does this help solve the problem? (It seems to be a step backward, not forward.) Please clarify. Thanks! (Joseph A. Spadaro (talk) 15:17, 4 July 2011 (UTC))

July 3

I need a reputable tool to end my PC errors. If ErrorEnd isn't one, what is?

If you've heard of ErrorEND, it's supposed to find a good assortment of PC errors that either slow down my computer, or compromise how some software runs.

I'm having a hard time finding reviews on ErrorEND. What can you find on this alleged tool to fix errors on my PC? Should I fork over my funds to upgrade it to a fully-workable version?

If it's not something I should have, what should I have instead? Also, if there are free options, please feel free to list those as well. (Please, just so long as they're reputable. Thanks.) --70.179.165.67 (talk) 08:19, 3 July 2011 (UTC)

We need to know what kind of errors your PC is getting, before we can recommend a fix. StuRat (talk) 08:34, 3 July 2011 (UTC)

What sticks out a lot is that I keep failing to install 4 updates of Windows Update:

• System Update Readiness Tool for Windows 7 (KB947821)
  • Error code: 80070003
• Windows 7 Service Pack 1 (KB976932)
  • Error code: 0x800f080d (800F080D)
• Security Update for Microsoft Office 2007 System (KB2509488)
  • Error code: 80070663
• Update for Microsoft Office 2007 System (KB2539530)
  • Error code: 80070663

When I searched these codes, it brought me to some tech support wiki page that offered the solution to download/purchase ErrorEND. I figured that I may find a free alternative instead, which is another reason why I approached you all. --70.179.165.67 (talk) 12:47, 3 July 2011 (UTC)

80070003 is COR_E_DIRECTORYNOTFOUND: "The specified path couldn't be found." 80070663 is ERROR_PATCH_PACKAGE_OPEN_FAILED: "This patch package could not be opened. Verify that the patch package exists and that you can access it, or contact the application vendor to verify that this is a valid Windows Installer patch package." 800F080D was not found by the Microsoft error lookup tool that I used. These are impressively unhelpful.

This is worth a try (I found it by searching for 80070003). You can also download Windows 7 SP1 bypassing Windows Update, and that might, if you're lucky, fix the problem with the other updates. You would probably want one of the last two files, "...-X86.exe" for 32-bit or "...-X64.exe" for 64-bit.

I wasn't able to find the ErrorEnd-recommending page that you mentioned, but there are a lot of web sites out there that serve millions of autogenerated pages saying "Are you having problems with X? Try Y" where X is culled from some database of search terms and Y is the dodgy product being marketed. Some are designed to resemble wikis, like this one. See also this previous ref desk thread. -- BenRG (talk) 18:27, 3 July 2011 (UTC)

There are an amazing number of these "registry fixing" programs out there. I'm not sure why. I guess there are enough gullible buyers to keep them all in business. CCleaner is a free tool from a fairly reputable company that does similar stuff. As far as I can tell it's as useless as the other tools of this kind, but perhaps it will do something for you. -- BenRG (talk) 08:44, 3 July 2011 (UTC)

I use CCleaner whenever I remove a program— it has helped when I have an install issue when I upgraded from trial software to a full version. Registry cleaners are over-rated, but can help in certain situations. I have a laptop with Windows 7 that gives a 0x800f080d whenever I install SP1. I have gone through all the troubleshooting with no joy and plan to nuke and pave soon. ---— Gadget850 (Ed) ^talk 02:42, 4 July 2011 (UTC)

Running a 32-bit .dll on a 64-bit Windows system.

Hi. I've got an application that I wrote some time back (in Java), that had a small separate .dll for reading hardware directly (keyboard and joystick). Upon running this on my new Win 7 64-bit PC I get a Java error: "Can't load IA 32-bit .dll on a AMD 64-bit platform". I've got the .dll source code somewhere (I hope!), so I could probably recompile it, but it would probably be more sensible in the long run to do things a different way, and eliminate the .dll. In the meantime, is there a quick work-around to load the .dll in some way, just so I can see whether the rest of the application works? (Hopefully it will, but I may have done something daft...). Thanks AndyTheGrump (talk) 20:03, 3 July 2011 (UTC)

You can't mix 32-bit code (the DLL) and 64-bit code (the Java runtime) in the same address space. You'll have to recompile the DLL, use the 32-bit Java runtime, or write a separate 32-bit program (in any language) that loads the DLL and talks with the Java process by some IPC mechanism. -- BenRG (talk) 22:38, 3 July 2011 (UTC)

Thanks - I was beginning to suspect as much. I think using the 32-bit runtime sounds the simplest solution for now - The only C++ compiler I have available is the free MS Visual C one, which doesn't compile 64-bit apps. AndyTheGrump (talk) 23:00, 3 July 2011 (UTC)

Yup, that did the trick (and my Java app seems to work :-) ). I'm running it from a .bat file, so I just used the full path to the 32-bit Java.exe to run it ("C:\Program Files (x86)\Java\jre6\bin\java" -jar "D:\D Scratch\MyVeryIffyJavaApp.jar"). AndyTheGrump (talk) 23:59, 3 July 2011 (UTC)

scan& record

I would like to know if there is anything out there to scan and then record info from barcodes. i have ~ 1500 dvd's and I would like to record them to computer(their titles, etc)173.53.32.89 (talk) 21:19, 3 July 2011 (UTC)

You want a barcode reader? --KägeTorä - (影虎) (TALK) 00:05, 4 July 2011 (UTC)

A barcode reader would be necessary but not sufficient. The only information in the barcode is the number that you see written beneath it. It would also be necessary to have software that can look up the number and pull down the desired information. Looie496 (talk) 00:33, 4 July 2011 (UTC)

The problem is that those were likely applied by retailers, each of whom use their own numbering system, and, if some are many years old, those bar codes may not be supported by their current systems. So, you would need to have access to all those retailer's current and past databases, which they aren't likely to grant. StuRat (talk) 00:42, 4 July 2011 (UTC)

I don't think that's right -- I think the bar codes are a property of the DVD and there is a universal numbering systems for DVDs. It's possible to get information about a DVD by searching on the web for the numbers printed at the bottom of the barcode. Looie496 (talk) 00:50, 4 July 2011 (UTC)

Note also the barcodes that are on most products aren't unique to the retailer. They are usually EAN-13 containing a Global Trade Item Number. The vast majority of products in Europe and North America (well at least the US and Canada) and Australia+New Zealand contain such a barcode since retailers require it. In the past some retailers may have added their own seperate barcode but AFAIK in said countries this practice has mostly died out. Note even when retailers add their own barcodes the products will usually still contain an EAN-13 because the manufacturer hope to sell their products to a wider market including retailers who expect it. Well I'm not sure about the US, but considering they invented the Universal Product Code it would surprise me if retailers still added their own barcodes or if many products were sold without either a UPC or EAN-13. Home brands and brands or products unique to a retailer will of course not be found in other retailers (although will still usually contain an EAN-13) but for non home brands you will often find the same product with the same barcode across different retailers. (The barcodes may vary depend on things like the place of manufacture.) Of course this doesn't mean it's easy to find what the product is based on the EAN-13, AFAIK there's no universal database and based on my tests with a phone barcode scanner the public that databases do exist contain rather few products. Nil Einne (talk) 12:02, 4 July 2011 (UTC)

implementing a subset of SQL

as a learning exercise, I'd like to implement a subset of SQL as a C++ program, or, more specifically, I'd like you to do it. Then I'll just paste it into a file and run it with gcc. Could you give me a 40-200 line C++ program like that? It doesn't have to be optimized or do any file i-o, I'm just wondering about how you parse the sql commands at all, and what these rows and columns and joins and whatnot, how that might possibly relate to C++. Is it something where you have to have an "engine" you write that continually parses new sql statements (like a BASIC interpreter) or can you make it more optimized than that? I guess I'm saying that I'm really really struggling with basic database concepts and it would be an immense help if I got a toy implementation in C++, so that I can translate the thing to something I already know. I began this post in a somewhat flippant way, but I really can't write the sql parser by myself! I am NOT getting these database concepts enough :) Thanks... --188.29.120.206 (talk) 23:18, 3 July 2011 (UTC)

Parsing the commands doesn't have much to do with database concepts. Writing language parsers is a very specialized task -- many of them are written using special tools such as Lex and Yacc. I don't specifically know what software the available SQL parsers are written with, but whatever it is, the source code is likely to look unpleasant. Our article on parsing may help to give you a conceptual overview. Looie496 (talk) 00:44, 4 July 2011 (UTC)

couldn't you give me a toy 100-200 or 300 line C++ program that is almost kind of like a database in some rudimentary way? So I can at least get started in understanding something... 188.28.160.38 (talk) 01:42, 4 July 2011 (UTC)

You're not going to find a 200 line DBMS. If you want to look at something that is relatively small compared to most database systens, I'd take a look at the source code for SQLite, which is written in C. Still, you are talking something on the order of 100K lines of code, rather than 200. Your request simply isn't satisfiable. You're going to need to dive into a bigger body of code if you want to see how a database system works. ~ Mesoderm (talk) 01:59, 4 July 2011 (UTC)

Sorry, but I'm 100% sure you're wrong. There is SOME interesting subset of sql that you could put in 200 lines. It doesn't have to really be a DBMS or an RDBM or an RDMB or whatever that stuff is. All it has to do is present SOMETHING to me, so I have more than NOTHING, which is what I have now. 188.29.88.52 (talk) 05:30, 4 July 2011 (UTC)

No, I'm not wrong, as I'm sure an extensive search for a 200 line SQL engine will convince you. However, perhaps if you explain what problems you are having with SQL, somebody here could point you to a better way of figuring it out than trying to write an SQL engine on your own. Which SQL concepts are you having problems with? ~ Mesoderm (talk) 05:46, 4 July 2011 (UTC)

This research article discusses teaching relational algebra concepts via an interactive programming environment. However, their implementations were in Visual FoxPro and Turbo Prolog, and thus unlikely to be readable for a C++ programmer. 130.188.8.10 (talk) 10:12, 4 July 2011 (UTC)

I can imagine what you are asking from two different points of view. Do you mean you want to write a simple RDBMS system that will parse some standard SQL statements and actually work like a database; and do all that in a few hundred lines of C++? - Like the others have said, I would agree that is very probably impossible in such a small space. Alternatively, are you looking for a fleshed-out example that uses a particular RDBMS's API to achieve some specific aim, something that is longer then the short examples given in RDBMS manuals? Astronaut (talk) 11:08, 4 July 2011 (UTC)

If I were interested in implementing a basic SQL database, the SQL part is the last thing I'd do. In order:

1. I'd write the storage engine, which is in essence a key-value store. Probably the easiest thing to do for that is a hash table (a simply in-memory hashtable will run to a dozen lines of code or so, with as much again to bulk load and save the whole thing to a file; a toy implementation doesn't need concurrency, ACID, or robustness). Or you could use Berkeley DB, which is in essence a fancy persistent hash table. That gives you the logical equivalent of SELECT * FROM foo (and the equivalent INSERT)
2. Then I'd implement the schema, which is another table (or two), which stores the names and types of the fields of a given table. That allows you to construct a function that takes the name of a table and returns a type/name structure. Armed with that, you can parse the raw value stored in the hashtable and get a meaningful typed tuple from it. With that you can logically implement SHOW TABLES and SHOW COLUMNS, and in particular SELECT bar,zork,zap FROM foo
3. To show it was useful you really need to be able to do a simple inner join. A toy implementation might only do joins on column equality, in which case a (perhaps inefficient) implementation is very simple.
4. To get test data in, and results out, I'd need some utility functions like CREATE TABLE
5. At this point I'd have a basic data store and a bunch of C functions like db_select(table,[fields]) and db_join_equal(tableA,tableB,fieldA,fieldB). That's a basic database API. To make it a SQL database you need to parse a string containing a SQL command. For a very simple toy language (where you brook no variation) you can probably do that with a few lines of code; if you planned to support a fuller SQL subset later you'd probably think about a parser generator like yacc. Either way, that turns stuff like "SELECT foo FROM bar;" into a few calls to your database API (one to find the table, one to retrieve its schema, a loop to pull each row and a schema-aware operation to extract foo only from each row).

-- Finlay McWalter ☻ Talk 11:21, 4 July 2011 (UTC)

July 4

Perpetual loop problem

I have an occasional problem when editing Wikipedia. I’ll be madly typing away, when my fingers apparently accidentally hit the wrong combination of keys, and up comes a box in the top left of the screen, with the following one below the other:

• Restore
• Move
• Size
• Minimize
• Maximize
• X Close Alt + F4.

When this happens, I can do nothing about it. No matter what I try (and believe me, I’ve done everything I can think of), I cannot remove the Restore box and return to what I was typing. That’s probably because I have no idea which combination of keys I inadvertently pressed to make this happen in the first place. The whole system goes into some perpetual non-responsive loop, and the only thing I can do is to force my internet connection to close down using Windows Task Manager (which sometimes takes 5 minutes to respond), losing everything I’d just been typing, and start again from scratch.

I think I can narrow the offending keys down to something on the bottom row, which contains from left to right:

• Ctrl
• Windows logo
• Alt
• space
• Alt
• Windows logo
• a weird rectangular symbol with an arrow superimposed on it, pointing roughly North-west
• Ctrl.

Can anyone please tell me what I do wrong, and how I can fix it more easily than I’ve ever been able to discover so far? This has been happening on and off for at least 7 years, so I’d be glad of some relief.

I currently have a Compaq keyboard but I'm sure this has happened on earlier keyboards I've used in that period.

For the record, while I am not exactly a stranger to the other ref desks, this is the first time I have ever intentionally even visited Computing, let alone asked a question (I first arrived here via an OP's link just last weekend). So, I’m expecting great things of you. Thanks in advance. -- Jack of Oz ^{[your turn]} 09:27, 4 July 2011 (UTC)

ALT+SPACE makes this pop-up menu appear. ESC, or clicking the mouse somewhere that's not on the pop-up menu makes it disappear again. Or at least that's what happens on the Windows and Linux systems I use.

It is worth noting that if you continue typing after the menu appears, most letters won't do anything, but the following six letters do:

• R = Restore (de-maximise the window),
• M = Move (4-headed arrow appears to let you move the window with the arrow keys)
• S = Size (4-headed arrow appears to let you resize the window with the arrow keys)
• N = Minimise (window disappears to the task bar)
• X = Maximise (window fills the screen)
• C = Close (...the window. If lucky you will get a save prompt) Astronaut (talk) 09:52, 4 July 2011 (UTC)

OK, I've confirmed that Alt + Space is what's doing it. I feel that knowing the specific cause is a great leap forward already, even if the solution is not yet there. Pressing Esc does nothing, and clicking the mouse anywhere on the screen at all also has nil effect. I will try those keys you mention next time this happens. In the meantime, I'd love to know what the purpose of the Restore box is, and why it's apparently so easy to get it without ever wanting it, but then not knowing how to get rid of it. How can that be "user friendly"? And why does my system go into a loop? What's it thinking about? Will it ever restore itself to where I started out from, and if so, how long would I have to wait? Thanks. -- Jack of Oz ^{[your turn]} 11:22, 4 July 2011 (UTC)

Since the early days of Windows, it has supported keyboard shortcuts so you don't have to use your mouse. ALT+Space is just one of those shortcuts. Apart from some odd keyboard driver quirk, I can't think why ALT+Space gets you stuck in a loop. Are you sure the keys aren't getting stuck down by goo under the keys? How about trying to analyse which ALT key you are catching while typing a space and remove the physical key from your keyboard? And how about borrowing a keyboard to see if you have the same problem with that? Astronaut (talk) 11:37, 4 July 2011 (UTC)

That really is odd. What happens if you hit Alt next time you get this message? On my Windows computer, this brings up the "File" menu, just as if I'd hit the same key without the Restore etc. menu. Nyttend (talk) 12:13, 4 July 2011 (UTC)

That's exactly what I get normally. But when this loopy problem happens, absolutely nothing I do has any effect. Nothing except shutting it down and starting again. I've tried every key on the keyboard and all manner of crazy combinations, I've tried the mouse, nothing. This has happened about once a month, as a rough average, for about as long as I've been editing WP (December 2003). This site is pretty much the only wiki I ever visit (there have been others but they're very few and far between), and it only ever happens here. I will dig out my old keyboard and see if I can replicate it there. -- Jack of Oz ^{[your turn]} 12:33, 4 July 2011 (UTC)

IBActions

I have a project in Xcode, and I've made an IBAction, and hooked it up to a button, but no matter what I do, it just won't run whenever I build the app and click the button. Does anybody have any tips for me? I would greatly appreciate it. --Thekmc (Leave me a message) 12:48, 4 July 2011 (UTC)

Archive

On Windows I want to automatically check a url every 2 hours and record any changes in content. Like a Wikipedia edit history. What program does this? — Preceding unsigned comment added by 81.51.70.112 (talk) 15:16, 4 July 2011 (UTC)

Install FireFox and then install https://addons.mozilla.org/en-US/firefox/addon/check4change/ --Aspro (talk) 15:25, 4 July 2011 (UTC)

That doesn't save the content though. Sorry if I wasn't clear, I want to save the content locally as an archive which can be browsed like going through a wikipedia edit history. Or like archive.org s internet history viewer — Preceding unsigned comment added by 81.51.70.112 (talk) 15:37, 4 July 2011 (UTC)

It should be possible to use wget or cURL to only download a page if it has changed; a little bit of script-fu should can then copy the page to a new location. CS Miller (talk) 19:39, 4 July 2011 (UTC)

Mathematical calculations in MS word.

I frequently prepare reports that contain many mathematical calculations.Along with the calculations they contain a lot of texts too.I prepare these reports using MS Words.When I need to change a value, I have to edit all results depending on that value.It is a very tedious job.Is there any easier way? — Preceding unsigned comment added by 113.199.241.79 (talk) 16:15, 4 July 2011 (UTC)

Don't use MS Word? Not kidding. — Preceding unsigned comment added by 88.14.197.162 (talk) 17:55, 4 July 2011 (UTC)

MS Word cannot do calculations. It can only show what you type. You can get an addon package for MS Word (at least I think I remember someone mentioning an addon package in the past). There are only two standard office applications that can do calculations: Excel and Access. For this, Access is overkill. You can type up your equations in Excel and adjust the cell sizes (one cell per term) to make it all look right. You can have the values filled in with actual equations instead of typing the values. Then, you can copy/paste the table you produced into MS Word. Once in Word (if you pasted it as an office object and not plain text), you can double-click on the table and change a value to change the entire equation. -- kainaw™ 19:53, 4 July 2011 (UTC)

Actually Word can do calculations, using Field Codes and Formulas (see the Help), but they're a bit unwieldy to use, and not really suitable for anything but the simplest examples. AndrewWTaylor (talk) 20:32, 4 July 2011 (UTC)

What musical instruments were used for the Windows Theme?

I was just wondering. What musical instruments were used to make the Windows theme song? — Preceding unsigned comment added by 70.238.174.171 (talk) 16:35, 4 July 2011 (UTC)

It sounds like pure electronica to me (i.e., synthesizer and nothing else). Looie496 (talk) 19:53, 4 July 2011 (UTC)

How to view ppt. without bloatware?

I have WinXP with the latest version of Firefox. The free MS viwer for ppt. files is 60MB! Is there any non-bloatware and offline way of viewing ppt. files please?

(I avoid bloatware. I use AbiWord for word-processing (British dictionary available), Sphymic Software spreadsheet, and SumatraPDF. All a fraction of the size of OpenOffice etc. But I havnt got a means of viewing ppt. files yet.) 92.28.244.187 (talk) 19:50, 4 July 2011 (UTC)

60MB counts as "bloatware" for you? Really? – PeeJay 20:03, 4 July 2011 (UTC)

If you've been brought up on nothing but bloatware, then http://tinyapps.org for example may awaken you. 92.28.244.187 (talk) 20:50, 4 July 2011 (UTC)

No games with pre-installed Windows 7 PC

My dad recently bought a new Acer Veriton desktop PC with Windows 7 preinstalled, but none of the standard games (Solitaire, Freecell, Hearts, Minesweeper, etc.) came with it. Is there any way we can get these back? – PeeJay 20:05, 4 July 2011 (UTC)

Try this link. Mo ainm~Talk 20:12, 4 July 2011 (UTC)

Merci. – PeeJay 20:17, 4 July 2011 (UTC)