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January 5

is there a name for this type of computer hacking/stalking?

it focuses on collecting information, such as personal information about people. starts with easy methods, such as google and social media, resorts to hacking when needed. motive is mainly for fun (sometimes to know the people better), not for financial gain, not to harm people. —Preceding unsigned comment added by 218.186.8.241 (talk) 01:17, 5 January 2011 (UTC)

What you describe sounds a bit like Social engineering (security). But the goal is usually the same as other forms of hacking, some sort of gain and not just getting to know people. Dismas|^(talk) 01:54, 5 January 2011 (UTC)

White hat social engineering? Besides stalking your girlfriend or Lindsey Lohan, I doubt many people would do that...ResMar 03:40, 5 January 2011 (UTC)

Troubleshooting sound problems

I recently sent my 5.1 Surround Sound HPA2 Turtle Beaches (Product Page) in for repairs. So I switch to a couple of somewhat crappy single-jack headphones I have laying around. But for some reason, the computer doesn't even recognize them when I input the jack - no response. How should I troubleshoot? Thanks, ResMar 03:04, 5 January 2011 (UTC)

First thing is to check that the jack is all the way in. Then check the various volume and mute settings. StuRat (talk) 21:02, 5 January 2011 (UTC)

Done. No luck :/ ResMar 23:58, 5 January 2011 (UTC)

OK, next step is to try the headphones elsewhere and try other headphones on that computer, to isolate the problem. StuRat (talk) 22:00, 6 January 2011 (UTC)

WEP Password Revelation

Hello.

   I'm looking for either open-source software or atleast freeware which is compatible with Windows 7, and can reveal the password of a WEP network without resetting or modifying the password. The target WEP router is my own - if it something gets screwed up, I can just reset the router and start over. This is for my own personal interest, not for bandwidth-stealing or any other illegal activity.

   Thanks everyone. Rocketshiporion♫ 05:39, 5 January 2011 (UTC)

I've not tried it (Who still cares about WEP?), but Aircrack-ng seems to be popular. APL (talk) 05:52, 5 January 2011 (UTC)

You will find that you will encounter number of roadblocks in your attempt. Firstly, not every adapter is capable of monitor mode that is required for an adapter to be able to capture packets without being associated with an access point. And if it is it may not be capable of packet injection which forces the AP to generate new IVs (weak breakable packages). Without this and with low to no network activity, you may be looking at weeks of gathering required number of IVs even if you have a card capable of monitor mode. And even if you have a card with all of those it can be hard to tell the exact model because manufacturers do not like to make such info easily attainable and user compiled lists are often incomplete or even inaccurate. And on top of all of those, even cards capable of one or the both functions often do not have Windows drivers. Therefore if you are not willing to dabble into Linux and command line you will find you have next to no chance of breaking the WEP encryption. If however you are willing to do that and obtain an adapter that works if you do not own one, you should probably grab a copy of BackTrack 4. This is a live Linux distribution, containing above mentioned Aircrack-ng, easily the best wireless cracking suite, and drivers for most wireless cards capable of monitor mode and packet injection.

Assuming you satisfy all of above condition, it's just a matter of booting up BackTrack and running few commands. Google it, it is everywhere and also the official documentation for Aircrack-ng has been most useful for me. With all of that you can crack virtually any WEP network within 10 - 15 minutes (only factor out of your control is if the AP does not generate first IV which can happen if there is absolutely no traffic on the network). And with some luck and crappy password on the target's part, with the same suite you can crack WPA and WPA2 passwords too. --110.174.117.185 (talk) 21:51, 5 January 2011 (UTC)

If you have a connection to the router or have a ethernet cable so you can connect then you can probably log on as most routers never have the password changed for inside access. I just had a look at my router by looking at http://192.168.0.1 and the wireless password has stars in the box. However when I saved the configuration and looked at it with a hex editor the password was there with a simple xor of each byte with a constant to obscure it - so one could find it by hand. Dmcq (talk) 22:32, 9 January 2011 (UTC)

If you have a laptop that may still have the password for the network stored, try WirelessKeyView, it'll give you any WEP/WPA passwords remembered from connecting to wireless networks. Dhoare12 (talk) 22:24, 10 January 2011 (UTC)

Kaspersky Antivirus Services Could Not Start

We are using kaspersky antivirus Business space securety

kaspersky antivirus 6.0 install properly but services is not start

Please help me about this

Transferred from Language Desk. Richard Avery (talk) 08:04, 5 January 2011 (UTC)

Contact Kaspersky technical support here.--Shantavira|^{feed me} 11:41, 5 January 2011 (UTC)

When was 'bigint' introduced as a data type in Microsoft SQL Server?

I'm having some difficulty finding an answer to this question. MSDN seems to be a sea of unrelated documentation without an effective index of SQL Server developer guides for older versions of the product. So can anyone provide me with an idea of when bigint (64-bit integer) was introduced as a datatype in SQL Server? - for example, is it supported in SQL Server 2000? How about earlier versions?

Also, are there any recent versions of SQL Server which do not support bigint? Thanks. Astronaut (talk) 10:27, 5 January 2011 (UTC)

Having just tried it, I can confirm that bigint is supported in SQL Server 2000 - I don't have access to anything earlier. AndrewWTaylor (talk) 14:58, 5 January 2011 (UTC)

I googled your question and the third result is a book that says: SQL Server 2000 introduces the 64-bit integer (bigint), ... --Sean 15:44, 5 January 2011 (UTC)

Connecting to internet on my laptop via mobile data-cable

I've managed to connect to the internet on my laptop via my mobile phone's bluetooth connection. But after getting a data-cable, I can't connect to the net via the cable (using a dial-up connection) unless both my lap's and my cell's bluetooth are switched on.Is keeping bluetooth on mandatory for connecting to the net? Doesn't that kind of defeat the purpose of having a data-cable in the first place?? Is there any way to connect to the net without switching on my lap's/cell's bluetooth? Thanks in advance!117.97.129.0 (talk) 13:24, 5 January 2011 (UTC)

Are you sure you are actually connecting with the cable? F (talk) 00:05, 7 January 2011 (UTC)

Yeah. I'm absolutely sure, because when I connect via bluetooth, it shows the bluetooth connection status as "connected", and when I use my data-cable, it shows the dial-up connection status as "connected". 110.225.188.86 (talk) 09:13, 7 January 2011 (UTC)

android phone site

Is there a website that lists the android phones available? I'm looking for one and the wireless carriers have disgustingly sad websites that cannot do something as simple as "show me the android phones with a full qwerty keyboard and wifi". -- kainaw™ 17:51, 5 January 2011 (UTC)

Comparison of Android devices APL (talk) 17:55, 5 January 2011 (UTC)

Found what I wanted: http://pdadb.net -- kainaw™ 15:04, 6 January 2011 (UTC)

Backing up Hotmail

When I asked about this a while ago, it was suggested that Mozilla Thunderbird could be used to back-up Hotmails email to my HD. Please could you tell me 1) if this leaves the emails still available online, and 2) if it is possible to back up the emails a section at a time (eg the last months worth for example), as backing up the several years of them at once may cause problems due to the bulk involved?

I don't know anything about the technicalities of emails, and would prefer not to have to get involved with anything complicated. If there is anything that can backup Hotmail emails just by clicking a button, or which is simpler to use than Thunderbird, then I'd be very interested to hear about it. I would likely only use it for backing-up, no other purpose. Thanks 92.15.1.103 (talk) 20:22, 5 January 2011 (UTC)

With Thunderbird, you can easily create a local folder (a folder on your local computer) and copy emails to that folder. You have the option to move or copy. Moving removes it from the server. Copy leaves it on the server. You select what you want to copy. You can copy one email. You can copy a month's worth of emails. You can copy all of the emails. -- kainaw™ 20:48, 5 January 2011 (UTC)

The answers for both questions 1) and 2) are "yes." Using Thunderbird to copy emails to local folders (as Kainaw described) will not delete them from the server. Thunderbird also has the capability to sort all mails by date; or to browse certain folders. Here are instructions for setting up Hotmail in Thunderbird and here are some illustrated instructions for saving local copies of emails from Idaho State University and from University of Southern California.

Unfortunately, backing up from Hotmail with a single click of a button is a bit tricky; it's not something that Hotmail is designed to do easily. Many other tools and programs do exist, but I am hard-pressed to think of any that would be easier than Thunderbird. Most will require complicated setup, or the use of the command line, and because they are less commonly used programs, there will be fewer illustrated how-to guides. Nimur (talk) 20:54, 5 January 2011 (UTC)

Thanks. The first two links are outdated, but the last one is still current. 92.24.188.182 (talk) 20:06, 6 January 2011 (UTC)

Webcam for a mac

Hi. I have a little 12 inch powerPC G4, running macosX 10.5.8. I want to buy a USB webcam for use with skype, and am worried that new webcams will only work with intel models. Can anyone recommend a budget webcam that is known to work on my hardware? Thanks, Robinh (talk) 21:38, 5 January 2011 (UTC)

You should be able to find requirements on online retailer listings, like at this one on Amazon, which says "Mac OS X 10.4.11 or higher…G4 800 Mhz or higher". You can get real-time suggestions and confirmations on IRC in places like irc://irc.freenode.net/mac, irc://irc.freenode.net/hardware, or irc://irc.freenode.net/electronics. ¦ Reisio (talk) 00:40, 6 January 2011 (UTC)

Thanks Reisio. I guess I was being a bit overcautious. Best wishes, Robinh (talk) 08:23, 6 January 2011 (UTC)

Resolved

finding diffs in sound files

I have sound files from field recordings that I recently found are not identical to their back-up copies. (I discovered this when I scanned my comp for duplicate files.) I'm afraid that some program I used to listen to them may have made changes, though I never saved anything. This won't matter if it's metadata, but I need to keep the sound quality as good as possible, and am not sure which copy to rely on. Is there any free/shareware out there that will show me where the differences are? — kwami (talk) 22:59, 5 January 2011 (UTC)

Surely the modification timestamps no longer match? ¦ Reisio (talk) 00:42, 6 January 2011 (UTC)

No, that's what's so weird: the timestamps do still match. I opened these files with SoundForge9, and I wonder if that's the issue. Or perhaps one of the files got corrupted after archiving, or when transfering to backup, but I have no way of knowing which one. (There are dozens of such files [out of hundreds which are still bit-for-bit identical], and any changes are evidently relatively minor. But when every syllable counts, even minor defects can be a problem.) — kwami (talk) 09:39, 6 January 2011 (UTC)

If you're on something Unixy, converting them to something lossless and uncompressed like wav and then doing a "cmp --verbose file1 file2" will tell you which bytes are different. You can then load both files into something like audacity and look for the changes at those locations. --Sean 14:07, 6 January 2011 (UTC)

I am also seeking a program that can strip ID3 tags and compute a hash of just the MP3 data. (Alternatively, we could actually do a correlation or a signal residuals comparison between the decompressed audio, but that'd be more computational effort). I have many duplicate files in my library that are unmodified except for ID3 data, and these duplicates are very difficult to track down. If anyone knows of existing software that can strip ID3 data, I might throw a script together to streamline the process. Nimur (talk) 22:14, 6 January 2011 (UTC)

http://id3v2.sf.net/ ¦ Reisio (talk) 21:32, 7 January 2011 (UTC)

Sorry, I'm not on Unix/Linux. Win7. — kwami (talk) 02:27, 7 January 2011 (UTC)

January 6

802.11g issues

Resolved

 – Magog the Ogre (talk) 00:42, 6 January 2011 (UTC)

OK, so I just disassembled my whole laptop (there was a screw stuck in it which wouldn't allow me to remove the temporary hard drive I'd put in, grr). During the process, there were a lot of wires in various and sundry places, even not plugged into anything. For some reason, The wires were mostly coming out of the monitor. However, as they weren't connected to anything on the further end, I didn't think it was a big deal where I put them back, so I didn't keep track of the original configuration and stuck them where it looked natural.

However, upon booting my computer, my wireless connection is hideous. I have a wireless router a few feet away from me and it's one or two bars in strength. Normally it's an easy 5 at this distance. Is it possible that I somehow goofed up the wireless signal by having the monitor's wires interfere with it? Or is there maybe a low-tech antenna that I did something stupid with (like stick it below the other wires, whereas it normally should be in its own space)?

By the way, I have a Dell d620 and an integrated Intel 3945ABG WLAN. Magog the Ogre (talk) 23:47, 5 January 2011 (UTC)

Scratch that; all the silly wires coming out were antennae with very small metal ends which attach to WWAN/WLANs; I just reconnected and it's all good. Magog the Ogre (talk) 00:42, 6 January 2011 (UTC)

HDMI Cable Prices

This 25 foot "high speed" HDMI 1.3 cable is US$ 15 [1], while this other 20 foot "ultimate high speed" HDMI 1.4 cable is US$ 250 [2].

A) Why is there such large price variation among HDMI cables of similar length? Does the more than ten-fold price increase result in a measurable increase in a cable's performance? When is the difference important from the perspective of the end-user?

B) How can an end-user determine what cable is "good enough" for a given application? I found it very confusing looking at more than an order of magnitude in price differences, and not knowing what kind of HDMI cable I ought to get. So, I bought the $15 cable to connect a computer to an HDTV and it seems to work fine. However, if the cable wasn't "good enough" what would an observer expect to see? Does a low quality cable result in subtle artifacts, or would it be a complete failure?

Many thanks for your help. Dragons flight (talk) 00:26, 6 January 2011 (UTC)

A) because crazy people will pay; no; never

B) the picture displays okay; buy the cheap one; it's a digital cable, so if it was genuinely defective then whole blocks would get corrupted and the failure would be very evident indeed.

87.115.79.246 (talk) 00:44, 6 January 2011 (UTC)

I'm fairly sure the only way you'd notice a difference is if you got a cable that doesn't support part of the system (for instance I've seen HDMI cables that do not carry audio), or I suppose there are cables that are better shielded against interference. Usually I think you'll find the cheapest cable is just fine, though connectors can sometimes be a factor, particularly if you disconnect/reconnect them a lot. If there's a conversion taking place within the cable/adapter (not the case with HDMI) you'd want to watch out for that, too. I personally doubt I'd ever blow $250 on a cable unless I already had equipment so expensive it came with its own. :p ¦ Reisio (talk) 00:49, 6 January 2011 (UTC)

For some reason people seem to be highly gullible when it comes to HDMI cable prices. I think they must equate "digital" with "magical". StuRat (talk) 05:08, 6 January 2011 (UTC)

Subtle artifacts are unlikely. A year or 2 ago the HDMI standard setting people in the US were interested in receiving any (undamageD?) HDMI cable that did actually cause problems, I don't know if this offer is still valid and I'm lazy to dig it up but it gives you an idea of how common HDMI cable caused problems actually are. These people appear to sell relatively fancy (although not I guess extremely expensive) US made HDMI cables but have some useful info here on the testing [3] and appear to be somewhat honest

Now, there is always, with HDMI, the question: does it matter? This is, after all, a digital signal, and will ordinarily generate only one of three types of results: perfect performance, noticeable partial failure (manifested by "sparkly" dropouts and/or flashing/loss of sync), or total failure (manifested by complete absence of a recoverable signal, and therefore a blank screen). It is for this reason that, in addition to carrying our Belden HDMI cables, we also carry some very economical Chinese cables. Any cable which performs perfectly in a particular application is as good as any other cable which performs perfectly in that same application--but here there is a caveat, which we will pose as a question.

The rest of their website also appears to have some useful info and again from a quick glance largely free of bullshit.

I believe monoprice are a common source of HDMI cables in the US. Dealextreme and other such sites would probably be a decent source worldwide.

P.S. The HDMI cable offer is here. AVSforum itself is good place to read info on HDMI cables without bullshit (well as with most forums, some posters may speak bullshit, but there are also enough knowledgable posters who tend to call them out on it. You can also find descriptions of real problems because of HDMI cables there. They appear to usually be either drop outs, and sometimes clearly noticeable speckled pixels.

Nil Einne (talk) 09:25, 6 January 2011 (UTC)

Mapping a peculiar keyboard key to start program

My laptop has a button which used to trigger software (Acer PowerSmart Manager) which was supposed to reduce power consumption through undisclosed methods. The program was an irritation since it overrode screen brightness settings (actually making the screen brighter than I wanted it) and could not be customised so I uninstalled it. I would like to reasign the button to opening a program called GameBooster which I can use to close down many programs at once and restart them all again at a suitable time. The problem is that I don't know a) how to find out the scan code of this peculiar key (I think it might actually simulate two or more regular keys being pressed at the same time) nor b) how to make this trigger the execution of the GameBooster program (preferably without running an additional application). Surely Windows 7 has the capacity do this built in? --89.243.132.112 (talk) 01:39, 6 January 2011 (UTC)

Try AutoHotkey. 87.115.79.246 (talk) 01:48, 6 January 2011 (UTC)

Torrent: starting impossible, downloading possible

Could it be that a firewall blocks the starting of a torrent download, but does not block the downloading of already started torrents? It seems to me that I am having this problem in an internet-café. It would made sense if the torrent client needed different ports for each action. 13:02, 6 January 2011 (UTC) — Preceding unsigned comment added by Quest09 (talk • contribs)

No, it is the same thing. You probably got some dead torrents, without peers, that won't start. Try searching for fresh torrents and test it with them. —Preceding unsigned comment added by 83.40.250.126 (talk) 13:50, 6 January 2011 (UTC)

Couldn't type edit summary or search or turn text blue to copy and paste

A library computer had some sort of mouse problem which I reported here because it was affecting my ability to use Wikipedia.

When I first signed on I got a message about Internet Explorer 8 which indicates that the computer probably had that.

When I would try to turn text blue to delete it or copy and paste it (for Wikipedia editing) I would get a dot in place of the cursor, with an up arrow above it and a down arrow below it. I was using the correct mouse button, so don't anyone try to tell me the mistake was mine.

When I would try to search I couldn't type anything. I also could not type an edit summary. Furthermore, I got a lot of edit conflicts on one person's talk page when I was the only one editing. I may have mistakenly clicked on "save page" when I intended to preview, because I was having trouble remembering the correct vandalism template, but that doesn't account for all the edit conflicts.Vchimpanzee · talk · contributions · 18:30, 6 January 2011 (UTC)

Because this is a library computer and not yours, you have no means of knowing who has been using it or if the computer/mouse/keyboard is not damaged in any way. It is obvious that whatever mouse button you clicked was registering as a middle-button click, which brings up the scroller icon that you saw. It could be that someone broke the mouse. It could be that someone thought it funny to go into the mouse settings and swap the buttons around. How can you possibly expect anyone here to know what happened? -- kainaw™ 19:38, 6 January 2011 (UTC)

There are mouse settings that can be changed? You seem to know a lot about this. Also, this doesn't explain why the edit summary couldn't be typed or the search box couldn't be used.Vchimpanzee · talk · contributions · 20:37, 6 January 2011 (UTC)

File manager

On Windows 7, what is the best file manager for dealing with directories containing 10,000+ files? Windows Explorer is awful and usually crashes taking the whole system down with it. 7zip file manager has been a lot better but it too sometimes crashes, although without the system-wide disruption Windows Explorer causes. Any others? 82.44.55.25 (talk) 18:34, 6 January 2011 (UTC)

What are you trying to do with those directories and files? -- kainaw™ 19:35, 6 January 2011 (UTC)

Browse them, move them, copy them, sort them by date, name, type etc. Everything you'd do with a typical file manager and a directory, except on a bigger scale. 82.44.55.25 (talk) 20:36, 6 January 2011 (UTC)

I'm sure there are Windows Explorer clones that can manage it, but it's even more likely, IMO, that most orthodox file managers would have no trouble with that many files. If you get down to a command prompt you'd have even less trouble. ¦ Reisio (talk) 20:57, 6 January 2011 (UTC)

AOL mail ad problem with Firefox

I've experienced this before. For some insane reason if I decide to use an AOL mail to save the information I am collecting from various web sites, an ad will decide to create havoc with the computer even though I am not even on the page. Usually this happens with Internet Explorer but today it was with Mozilla Firefox. I was actually on a mail service other than AOL but it uses the same sign-in system and the email format is similar.

The computer froze and before pretty much everything disappeared I saw a "Waiting for xxx.xx.xx.xx message at the bottom of the screen. Normally there is a web site, but in this case there was an IP starting with 205. The screen went white except for a blue border and a wider a blue line at the top with the Firefox logo, the name of the email web site, and the minimize and maximize buttons and the red X. I got the message "Not responding" when I tried to do anything. Then the web site I was actually on when the other page misbehaved had the same look on its screen. At one point even the name of the site disappeared. The taskbar buttons would disappear and reappear, and sometimes there was more than one for each site. Eventually everything came back. I don't understand what happened or how to stop it.Vchimpanzee · talk · contributions · 18:39, 6 January 2011 (UTC)

At a guess, it sounds to me like an advert using Flash got stuck trying to download something from 205.xx.xx.xx. I'm sure there is a flash ad blocker you can get as a plugin for Firefox. Astronaut (talk) 21:27, 6 January 2011 (UTC)

Necessity of Antivirus Software

My PC came with 3 free months subscription to BulGuard antivirus software which expired some time ago. Am I running much of a risk by not having regularly updated antivirus software on my machine? I run Windows 7 and install all the security updates. Thanks Stanstaple (talk) 18:49, 6 January 2011 (UTC)

If you have ALL of the security updates, you have Microsoft Security Essentials. However, you need to understand that even with every anti-virus program known to man, you are only protected against virus activity that is known. Further, you are not protected against user ignorance/stupidity. If you download something off the Internet, through email, through a website, through P2P, etc... you are opening up the possibility of a virus or malware problem. Even if the file comes from a "friend", you don't know if your friend already has a virus/malware problem. In the end, using a networked computer means that you are accepting a risk of virus/malware problems. By choosing the most popular operating system, you increase that risk significantly. -- kainaw™ 19:29, 6 January 2011 (UTC)

I added the caveat "networked computer", but as has been recently demonstrated in Iran, even a computer system that is completely removed from the Internet can fall victim to an Internet-based virus. -- kainaw™ 19:31, 6 January 2011 (UTC)

Yes. You can easily install a good-quality and free anti-virus, such as Avast!. Uninstal "Bulguard" first. There is List of antivirus software but I use Avast! and would recommend it. 92.24.188.182 (talk) 20:01, 6 January 2011 (UTC)

You don't need anti-virus software if you keep your computer up to date and avoid running programs and opening documents from people you don't trust. I don't use an anti-virus program and I haven't gotten a virus in three years. I'm running Windows XP. Windows 7 is more secure against attack than Windows XP. Just make sure Windows (and Adobe Reader, Flash Player, Java, etc.) are updating themselves automatically.

However, if you (or someone else who uses your computer) is easily tricked into installing viruses or opening malicious PDFs (or Word documents) in your e-mail, then consider getting a paid anti-virus program like Kaspersky or BitDefender. Free anti-virus programs are not as good at detecting virii as paid programs are.--Best Dog Ever (talk) 20:52, 6 January 2011 (UTC)

Really? You mean the worst ever paid program is better than the very best free program? 92.24.188.182 (talk) 22:32, 6 January 2011 (UTC)

This chart should answer your question. In short, some paid anti-virus programs are worse than some free ones, but, in general, you get what you pay for. For more information, I'd click on "Test Report" under each product, and then click on "Specs." I generally recommend Kaspersky to people who ask, since it has good detection abilities and doesn't slow down your computer as much as Norton. It costs about $40 if you buy a single-user license: [4].--Best Dog Ever (talk) 22:39, 6 January 2011 (UTC)

But PC World (either the magazine or the shop chain) make thweir money through selling stuff, so they'd be disinclined to recommend something that's free. In addition, Norton has or at least had a bad reputation for interfering with your computer and leaving a lot of stuff behind after not uninstalling properly. Besides which, that appears to be just the subjective opinion of one person rather than being ranked on objective criteria. 92.24.188.63 (talk) 00:06, 7 January 2011 (UTC)

It isn't subjective. If you click on "Test Report" under each product, and then click on "Specs" it should give the detection ratio of each product. I don't recommend Norton for the reason you mention and because it slows down your computer, as I said earlier. I mentioned all of this in my last post.--Best Dog Ever (talk) 00:21, 7 January 2011 (UTC)

The free anti-virus is still near the top of the list, so its up to the OP to decide if they want a possibly (although I'm sceptical) slightly better detection rate according to your link in return for paying money. They would undoubtedly be better than not using an anti-virus. I've used Avast! after switching from AVG, and I've never had problems with either of them, and would recommend them. 92.24.188.63 (talk) 00:42, 7 January 2011 (UTC)

I've used AVG and Avast, too. When I worked as a computer repairman, I saw many computers that were infected with viruses that they missed. Their real-time protection was running, but it just didn't see the viruses. I got a lot more calls from customers with those programs installed than other anti-virus programs.--Best Dog Ever (talk) 10:47, 7 January 2011 (UTC)

You got more calls as these programs are the most popular, used by the most people. 92.24.178.121 (talk) 11:01, 7 January 2011 (UTC)

I have to disagree with Best Dog Ever over choice of Antivirus with this link which says that Norton loads up faster than Kaspersky. And perhaps instead of Antivirus, a real-time security package may be better instead. General Rommel (talk) 01:57, 7 January 2011 (UTC)

Kaspersky, according to the tests by PC World, scans files faster than Norton. So, if you have real-time protection turned on, that means that Norton will take longer to scan items as you open them up, thus, the general performance of your computer will take a hit using Norton vs. Kaspersky. I also like how you can turn Kaspersky off by simply right-clicking on the icon in the system tray and selecting "Exit." Norton is extremely difficult to turn off completely. I've had problems uninstalling Norton, as well. I've had it prevent computers from performing system restores. I've seen corrupt Norton installations slow a computer down by a factor of 10 or more. I don't like it. But if it works well for you, consider yourself lucky and don't let me stop you from using it. I like having complete control over my computer, as well, so I don't like how Norton automatically deletes benign programs I want to keep and such. So, it's not for everyone, but it may work well for you.

But, I'd still encourage all of you to try other anti-virus programs to see if you like them more than what you're currently using. That's what I did. I've used every single program we've talked about -- among many other anti-virus programs, over the years. So, I'm speaking from experience, as well.--Best Dog Ever (talk) 09:44, 7 January 2011 (UTC)

Just to bring the conversation back closer to the topic I intended; I'm more concerned about the question as to whether av software is necessary at all. I haven't run up-to-date av software for nine months, and have noticed no badness. Have I been lucky or is avs generally unnecessary if you don't browse like a gobshite? Is mise 109.125.17.223 (talk) 00:21, 8 January 2011 (UTC) _{Got signed out-30 days already!} Stanstaple (talk) 00:38, 8 January 2011 (UTC)

If you've gone that long without a virus, you probably don't need an anti-virus program. This is probably largely due to a high level of discretion on your part, and partly because you probably keep your computer up to date, and partly because you're using Widows 7.--Best Dog Ever (talk) 04:37, 8 January 2011 (UTC)

URL for MSNBC mobile site?

What would be a persistent, dedicated URL for the mobile phone website of MSNBC? I'm trying to add it to the EL section; having a dedicated mobile site link would be good for users with slow connections and/or older computers WhisperToMe (talk) 19:10, 6 January 2011 (UTC)

Are you referring to http://www.msnbc.msn.com/id/21691139/ -- kainaw™ 19:34, 6 January 2011 (UTC)

That looks right to me. Thank you very much! WhisperToMe (talk) 19:56, 6 January 2011 (UTC)

Fan (?) problem on HP G60 laptop

Greetings one and all,

I have a HP G60 laptop - out of warranty - which has recently been making a lot of noise with its fan. Some of you will be aware that I had a brush with a dodgy website posted over on the LangDesk recently and may have been infected with malware, which I have (hopefully) removed, but this noise has been happening since around about then. I am not saying this is the cause, I am just saying it may be. Anyway, I have found my fan starting up - pretty loudly - at various times, whether I am using the computer or whether it is just idling. I have downloaded Process Explorer, which says my processors are at 67C and my 'ACPI' is 83C - this does not seem to be too hot (having said that, the computer does feel pretty hot to me, but it always has, to be honest). I have this computer as a dual boot, with Vista as the main OS and Ubuntu 10.10 on a secondary partition. Using Ubuntu (as I am now) I find it a lot quieter. The fan doesn't start up so often. This leads me to believe that there is something happening with Vista. So, I have multiple questions here:

• What should I use to completely scan and remove this 'virus'? (I have used AVG Int Sec 2011, and Malwarebytes)
• I have HijackThis, but it is useless because it tells me to 'show someone who knows'.
• Would a full reinstall of Vista just be the best thing to do?
• If it is actually a hardware problem (dirty fan?), then... any advice on how to go about cleaning it?

Sorry for the long post with multiple questions. I hope you can help.

--KägeTorä - (影虎) (TALK) 19:55, 6 January 2011 (UTC)

Removing dust from the fan and associated grilles can be quite easy, or it can be extraordinarily difficult. I'm not familiar with that particular model of laptop, but take a close look at the bottom of it and see if there is a removable cover near the fan (perhaps a cover that usually lets you access the CPU). Alternatively, you could remove the whole bottom shell of the laptop, taking exact note of where everything came from (again, this could be easy or almost impossible), but it is important you know how it all goes back together again; you might be able to download a maintenance/service manual. If you can get to it, any dust can be blown away or gently picked out.

Reinstalling the OS is an easy way to be sure you have eradicated an infection, but it can be a real hassle backing up all your stuff (photos, music, emails, documents, internet favorites, etc.), locating the install disks for your software, noting all your settings/preferences and what software you downloaded and still use. Reckon on at last a whole day's work. It'll almost certainly make your PC seem faster but you'll be a bit annoyed if it turns out to be dust or faulty hardware.

If your virus scanner and malwarebytes didn't find anything, it might be worth scanning for a rootkit (which might hide malware from your scanners). Astronaut (talk) 21:22, 6 January 2011 (UTC)

Thanks for that - I have decided to go with a full reinstall. I have the recovery disk on a different partition. AVG Int Sec 2011 has anti-rootkit on it, and that keeps picking something up, refusing to get rid of it (but doing it anyway), then picking it up again later (turns out it's Starforce Protection driver). I'm not comfortable (just yet) with pulling this thing apart, but I will do that if I find that a reinstall hasn't solved my problem. Time for a HUGE amount of work....... :( Still, it's better than having an overheated PC to throw away. Thanks. --KägeTorä - (影虎) (TALK) 21:47, 6 January 2011 (UTC)

The "noisy fan" symptom doesn't match a virus, to me. I don't think the fans have variable speeds, they are only on or off, so there should be no way for a virus to make it noisier by making it go faster. So, what does cause a noisy fan ? Some thoughts:

1) It could be dirty, as mentioned before.

2) It could be imbalanced. This seems likely to be a manufacturing defect, so I'd think you would have had this problem all along, unless you had it open and somehow damaged the fan blades.

3) It could be hitting something (like wires) with the fan blade. This, of course, could be very bad, if the wires are eventually severed (or just lose their insulation). The good news is that this is pretty easy to fix, just open it up and reposition some wires, possibly with the aide of a twist tie or two. Of course, you would need to replace any damaged wires, if it has gotten to that point.

4) It could need lubrication. I'd only expect this problem in an old computer that receives heavy usage. StuRat (talk) 21:57, 6 January 2011 (UTC)

When I said the fan was 'noisy', I meant starting up every now and then, but much more often than I ever noticed before. It sounds similar to my CD deck starting up, but more of a fan-sound (because it's a fan). Also, this was very often at a time when the PC was grinding to a halt - something which was also happening a lot more often, along with lots of CPU spikes. Anyway, I have reinstalled Windows (again!), and I seem to be having no problems with it. Thanks, anyway. --KägeTorä - (影虎) (TALK) 02:18, 8 January 2011 (UTC)

Loading and buffering times

Why is it when I just start up my computer videos buffer VERY slowly? This isn't one video or site in particular either because I have tried several videos and site and they all buffer slowly in the first hour or so before my computer "warms up" but then buffer pretty quickly. Text seems to load at a normal speed. Thanks. 24.92.70.160 (talk) 21:40, 6 January 2011 (UTC)

I would guess that your computer isn't storing the video playing software, so must download it, along with the content. Also, your computer may be doing updates and such in the background, slowing down the whole works. StuRat (talk) 21:46, 6 January 2011 (UTC)

Your ISP has a congestion problem right around the time you turn on your computer?F (talk) 23:52, 6 January 2011 (UTC)

OS

Hello all. I recently purchased a Dell D620 laptop, with Windows Vista pre-installed. I am not a Vista fan, so does anyone know of a good free operating system I could put on it? I am thinking about Linux, but I've never used it before and have no idea which are the best versions. Could anyone recommend an OS that is 1) free 2) has all of the features of the windows 3) is good with external devices (flash drives, external hard drives, and memory card readers) and 4) and has a built in DVD driver? The last one I would not mind skipping if I can find a free Linux-based DVD driver somewhere. Thanks, --T H F S W (T · C · E) 21:50, 6 January 2011 (UTC)

I don't know what features of Windows you're referring to, so it's hard to say whether any particular distribution can match them. I've been using Ubuntu for many years now and it does most of what you want. You may (this is not legal advice) be a bit out of luck looking for a legal DVD driver, depending on where you live. Marnanel (talk) 21:54, 6 January 2011 (UTC)

I live in BC. And you can't have an illegal DVD driver for a free OS, can you? I hear that Ubuntu is a lot like a Mac, so would a Mac driver work on a Ubuntu? --T H F S W (T · C · E) 21:56, 6 January 2011 (UTC)

The potential illegality is entirely because it's free software. DVDs use a scrambling system, and if you want to develop a descrambler you have to pay for a licence to discover how to do it, and you can't tell anyone else. Hence doing them as free software is problematic. Someone has worked out how to do it independently, but it caused no end of a rumpus. Macs run a version of BSD, which is similar to Linux but has no common ancestor; this is however irrelevant in discussing application software, whose only involvement with the kernel is through an API. Marnanel (talk) 22:19, 6 January 2011 (UTC)

In general, a driver for Mac OSX would not work for Ubuntu. However, it is unlikely you will have any need for that. Your laptop model has been tested with Ubuntu; your exact model may have slight hardware variations, but Ubuntu has excellent driver support overall. Regarding the DVD issue, the problem rarely applies to most users. The issue is not even about whether the driver is legal - it is whether it is free as in open source software with a compatible license to Ubuntu. See this information page. Depending on your country, the version of Ubuntu you download may be provided without DVD support "out of the box." To play DVDs, you must perform a few steps; this is usually perfectly legal but it changes your license agreement (an issue that most end users do not care about). "Ubuntu's commitment to only include completely free software by default means that proprietary media formats are not configured 'out of the box'. Ubuntu can play the most popular non-free media formats, including DVD, MP3, Quicktime, Windows Media, and more by following the instructions (here)." Nimur (talk) 22:23, 6 January 2011 (UTC)

Kubuntu — (I'd suggest version 10.04 LTS [LTS = long term support] at this time) should do nicely for someone coming from Windows. After installation it'll prompt you to install/configure certain non-free things it didn't come with, and you might need to follow https://help.ubuntu.com/community/RestrictedFormats/PlayingDVDs but after that you should be all set. ¦ Reisio (talk) 22:48, 6 January 2011 (UTC)

Linux is Not Windows -so you would do well to read this first. I use Ubuntu a lot because it is easier to install/use/maintain/etc/etc than any release of Windows. If you go down this route then Ubuntu 10.04 LTS would be a good version to start on and there is wide community support to draw on if you have problems. Avoid a dual boot system. For a novice, it can be difficult to maintain so just get ride of windows competently. --Aspro (talk) 22:56, 6 January 2011 (UTC)

You blithely mention that you're "not a Vista fan" but haven't given us an indication why. Perhaps some more info would help us to answer your question, and maybe the answer would be to simply configure a few things in Vista to make it more to your liking. I wouldn't chuck out an entire OS without good reason. If you've never used Linux before even Ubuntu will not be that easy at first. You'll miss all the software and utilities you're used to in Windows (perhaps you will find Linux equivalents). You can forget about your cellphone's PC connectivity suite, your digital and video cameras' drivers and software, your 3G card's drivers, printer drivers, any made-in-China PC gadget bought off DealExtreme etc. Some of these can be made to work, with difficulty. Remember the vast majority of manufacturers support only Windows straight out of the box, leaving you to traipse around internet forums A LOT every time you need to get something working properly. Also, if you expect to use any sort of specialised software (Photoshop, video editing software, CAD, etc.) then the free equivalents on Linux are simply no match for the commercial software available on Windows or Mac. Throw out your entire OS with caution is what I'm trying to say. Zunaid 23:16, 6 January 2011 (UTC)

Not OP but my experience with Vista wasn't a happy one, and it's well know for having a lot of problems. To the OP; I've only tried a few versions of linux, but Slax was pretty good in my experience and could do everything I'd expect from Windows. It can even be run live from disk without having to install, so you can use it and keep Vista as well if you wanted. 82.44.55.25 (talk) 23:34, 6 January 2011 (UTC)

Yes, I know a lot of computer geeks, and most have nothing but horror stories about Vista. I only got my laptop for the hardware. --T H F S W (T · C · E) 00:33, 7 January 2011 (UTC)

WP:OR I actually really liked Windows Vista (Business Edition). In addition to supporting loads of new stuff "out of the box," better video acceleration, more built-in video and audio decoding support, and streamlined enhanced web browsing, it also had numerous small "nice tweaks" style enhancements over Windows XP. The most notable thing I can think of was a seamless "file renaming" user-interface. When you selected a file in Explorer and hit "F2", it highlighted all of the filename except the file extension. (A major irritation in WinXP, after having used KDE extensively for years). With Vista, I never had a hardware crash, driver problem, or blue-screen. The Windows User Account Control effectively controlled access as I needed it; the Secure Desktop (which most people recognized as a "screen flickering" when UAC kicked in) was easy to disable. Windows Power Shell was amazing as an enhancement, and a really incredible replacement for the awful Windows Script Host that XP and earlier Windows used. Meanwhile Vista's support for legacy software, especially emulated modes, was great; the networking interface was very clean. Setting up user preferences was a breeze. I could not for the life of me understand any of the vague and generic complaints people ranted about on web forums). After using Vista Business for several months, I moved jobs to an "old fogey Unix shop" that had historically used DECs and esoteric Unix flavors; to my surprise, they had just completed an upgrade of all their terminals and many of their servers to Mac OS X. So, I had the opportunity to use an Apple system for the first time since System 7. I have to say, OS X was incredibly difficult to use, configure, and learn. Much could be attributed to "user error" on my part; but I could not understand why a computer designer would look at the human hand (which usually has five fingers), and then design a mouse with one button; and then decide to add seven invisible buttons. (It took me weeks to figure out that random screen-changes and application behaviors were due entirely to the various invisible buttons on my Mac Mighty Mouse!) And while OS X claims to be "unix-y", that's really only true up to a point. I can truthfully say I've used more flavors of POSIX operating systems than I care to list, and I have never had any behave so wonky as OS X. (ssh -Y, anybody? ... and why do I need fink if OS X "is Unix" under the hood? Nothing "just worked," not our code, nor our compilers, nor our networking scripts). Point is, operating system reviewers should be specific instead of saying "Vista sucked." They should say, "Vista's User Account Control interface irritated me," or "the new video driver abstraction layer interfered with my ability to pirate certain digitally-protected content." Those are valid complaints against Vista; but "Vista Sucked" is not. I highly re-recommend Aspro's "Linux is not Windows" article - it's a great review of what you should know to expect when hopping operating-systems. Linux isn't Windows; Windows isn't OS X; OS X isn't DEC; DEC isn't eCOS; eCOS isn't ThreadX; and so on. Every operating system is different. Nimur (talk) 01:10, 7 January 2011 (UTC)

My experience with Vista is similar to Nimur's opinion. The laptop I'm using now is running Vista and has been since I bought it 3 years ago. A new laptop preinstalled with Vista should work well, and I very much doubt you will experience any of the problems mentioned in the Criticism of Windows Vista article. At work I use Ubuntu 10.04 and I also find that very good too. However, there are a few niggles with Ubuntu: while I can usually find a solution, I have to go looking for it. In particular, Open Office seems OK at first but I have noticed it has a reduced set of fonts, colours, styles, etc when compared to MS Office 2007. This means a presentation developed using Open Office won't look the same when presented using a Windows machine - so bad that I got Windows installed in a virtual machine just so I could use MS Office. Astronaut (talk) 07:48, 7 January 2011 (UTC)

I would definitely recommend Ubuntu 10.04 Linux Desktop Edition. I have been running this OS in a virtual machine for a few months now, and I have found to be both easy to use and quite useful. Rocketshiporion♫ 12:56, 7 January 2011 (UTC)

There are many Linux operating systems you can run from a CD without installing, to see how you like them Listed here: List of live CDs. 92.24.183.6 (talk) 18:01, 7 January 2011 (UTC)

Freeware to reduce the size of PDFs

Can anyone recommend from personal experience (rather than just a Google search) any freeware compressor for PDFs please?

I've already searched on Google and found "PDF Compressor". The old version is 288k and blanked all the pages in the PDF. The new version is 1.2MB and is shareware. Is there anything else? Thanks 92.24.188.182 (talk) 22:37, 6 January 2011 (UTC)

IME breaking up a a PDF with gs or pdftk and then recombining with the same led to smaller files... might be more involved than you'd like, though. ¦ Reisio (talk) 22:51, 6 January 2011 (UTC)

AFAIK the only PDFs that will compress effectively are those with a lot of high resolution images. I have a paid-for PDF maker and compress these by printing them to PDF with a reduced resolution for the images. You could investigate free PDF creators to see whether any offer similar functions. --Phil Holmes (talk) 09:13, 7 January 2011 (UTC)

External HD Unix backup

I have an Ubuntu (Lucid) machine and an external disk (with twice the capacity of the internal drive) to back it up. What I currently do (for each partition of interest) is

1. Create a partition of at least the same size (usually slightly larger because of rounding).
2. Format it with the same sort of file system (partly to make the partition map match reality, although Linux uses 83₁₆ for everything, it seems).
3. Mount that temporary file system, check that it really is big enough with df -k, then unmount it.
4. dd bs=1M if=/dev/sda5 of=/dev/sdb6 (repeated on whatever schedule)

This seems to work: the target can be mounted and could presumably be dd'd back to the real disk to restore a hosed partition. However:

1. What does it mean that the partitions aren't exactly the same size? What happens when a (say) ext4 file system is smaller than the partition it lives on?
2. Does anything bad happen if two file systems on a disk share a volume label (as will happen if I put more than one copy of a partition (with a labeled file system) on the backup disk)?
3. If this isn't already it, what's the easiest reliable way to clone partitions? (Is there something like asr?)
4. What's the easiest way of making the external disk bootable? Is it just to give it a boot partition and throw grub on it, or is copying some sort of boot information from the normal disk preferable?

My data offer thanks in advance. --Tardis (talk) 23:12, 6 January 2011 (UTC)

You know you can dd to a file, right? That and a backup of your partition table (sfdisk -d) should suffice. You could also use rsync or rdiff-backup for something simpler. For booting you just need something to tell the system to boot it (BIOS boot menu [often F12], or boot loader [GRUB, etc.]), and something that will actually boot on the device. ¦ Reisio (talk) 23:31, 6 January 2011 (UTC)

Hm — "of course" I know you can dd to a file (everything is a file!), but it hadn't occurred to me that it might be reasonable to just have the backup disk be one big file system holding file system image files. (It would be even nicer if they could be compressed, since none of these file systems are even half full; is there a sensible archiver that captures absolutely everything about a file system except its unallocated space and perhaps its block layout?) That, the partition table, and the -o loop option to mount(1) ought to be sufficient (since then you can examine/recover individual files) except for booting; thanks for the idea. (I'm of course open to more ideas, though!)

As for booting, I just worry about the complexity of maintaining the boot setup among the various partition copies; it would be nice if it were automatic somehow. --Tardis (talk) 23:54, 6 January 2011 (UTC)

Some compression commands here: http://mark.koli.ch/2009/05/howto-whole-disk-backups-with-dd-gzip-and-p7zip.html ¦ Reisio (talk) 02:24, 7 January 2011 (UTC)

Those will try to compress the image as a whole, and if you have "recently" zeroed the disk, so that all unallocated space is trivial to compress, that's great. But (for example) I have 13 GB duplicated from another computer that I'll delete once I'm sure it's safe elsewhere, and even p7zip can't be nearly as efficient as a tool that recognizes that they've been deleted. (See also my reply to Nil Einne.) --Tardis (talk) 17:05, 7 January 2011 (UTC)

If the image is stored as a file and the unallocated space isn't read (I think even dd can do the later?) it could be considered all zeros so all you need is a program that writes it as a sparse file. From a quick search a simple way to compress it would be to pipe it to an appropriate compressor although I guess that would be obvious to anyone with some *nix familiarity [5] (actually I appear to be repeating what you said, perhaps I misunderstood the compression comment). That also mentions partimage [6] Nil Einne (talk) 01:57, 7 January 2011 (UTC)

dd certainly can't avoid copying unallocated space (since it has to work even if there's no file system on the device at all). partimage says right on that front page that it copies only the allocated data; it doesn't do ext4 but the similar tools fsarchiver and partclone do. I also found a clever hack to let image compression à la gzip work: create/delete a huge file of zeros to make the empty space compressible (or sparse). I'm still wondering about the other three questions, but these new tools/ideas are probably sufficient in practice. Thanks. --Tardis (talk) 17:05, 7 January 2011 (UTC)

Is 'dd' really the best way to back up a linux system? (Keep in mind, dd copies every bit off your disk, whether there is filesystem data on it or not, errors and fragmentation included.) Have you considered using rsync or rdiff-backup? Duplicity is a pretty nice tool for simply managing backups in a more efficient way. I do my backups to an external disk using rsync's --link-dest option for a poor-man's snapshots, which means that the only new files created in the new sync are the ones that have changed. Of course, to restore a system, you'll have to create the partitions, volumes and filesystems before restoring, but that might be easier than trying to make sure dd creates everything correctly. -- JSBillings 15:28, 7 January 2011 (UTC)

January 7

Compiling applications for NT4 MIPS?

So, I have Windows NT 4.0 running on a MIPS Magnum R4000. Now as you might know (and as the article says), there are very few applications for NT4 MIPS, so I have internet connectivity but no web browser to begin with (except IE2, which doesn't really work). Now, I do have Visual C++ 4.0 - I wonder if that could become any useful in compiling applications? Or is it not worth bothering? -- Prince Kassad (talk) 02:49, 7 January 2011 (UTC)

What is your objective? C and C++ code will compile for MIPS, but the architecture is sufficiently different that any reasonable application (like anything with a GUI) will be non-trivial to port. *nix has great support for MIPS, and your workstation in particular can run BSD and Linux. But what is your objective? A low-end $25 consumer digital camera has a more powerful MIPS core, probably with more RAM, higher-resolution LCD, and more modern peripheral buses than your Magnum; so if you're looking at hacking up some MIPS code, you might refocus your effort. If your goal is hobbyist recreation of the historical platform, it'd be a bit out of place to port modern software to the Magnum. Maybe you could port Android to it - there's a free documentary/webinar available through the MIPS website to train you up on that. Nimur (talk) 03:56, 7 January 2011 (UTC)

I'm not sure if Visual C++ had cross-compilers. Do you have a native MIPS version? The Windows APIs have changed a lot since NT 4.0... Lots of GUI apps indeed will be hard to recompile even if you have a working cross-compiler, so I generally agree with Nimur's recommendation to drop NT and try out something more modern (NetBSD in particular is a great OS that supports a dizzying array of platforms). But if you insist, the usual route I've gone when working with odd platforms is to first get a modern compiler and toolchain (e.g. gcc and friends) running, then from there try to build apps. Assuming that can get a MIPS cross-compiler, you should be able to cross-compile a small compiler, then use that to bootstrap gcc (which might require a couple other things like a shell, lex/yacc, etc. See the MinGW project for a ready-made set of packages you can start fiddling with. The MinGW folks might still have some people around with some knowledge about cross-compiling for MIPS, so their user groups may be a good help. Once you have the basic MinGW pieces in place, you can start compiling bigger packages like X11, and from there, Firefox and other tools that you're accustomed to using. If just using the machine is your goal, though, it's probably easier to use something like NetBSD where they've already gone through all the trouble of building you a userland. Then all you need to do is download and build the things you need. —Preceding unsigned comment added by 128.12.174.253 (talk) 03:44, 8 January 2011 (UTC)

Is this spam/a virus?

I got an email without a heading from someone I trust. I don't think she ever sends emails without a heading, and even more puzzling is that all it contains is a URL. Apparently the website is from France; I can provide the URL if needed. I don't see why someone would send and email with nothing but a URL; is it some kind of spam or is it a website with a virus/worm/whatever? Kayau Voting IS evil HI AGAIN 05:49, 7 January 2011 (UTC)

Yes, it is. I get such emails, too. I suggest you reply back to them to let them know their computer is infected, and likely everyone in their address book is now getting SPAM. StuRat (talk) 05:56, 7 January 2011 (UTC)

Thanks, I have. Kayau Voting IS evil HI AGAIN 06:20, 7 January 2011 (UTC)

Note that it is incredibly easy to forge the From: address of an email. This is rather common with spam messages. There is a possibility that the email did not come from her computer at all, but was instead sent from some other computer with a forged from: address. -- 174.21.250.227 (talk) 16:54, 7 January 2011 (UTC)

It could also have been that her email was hacked, so in that case you might want her to get her to change her password after disinfecting/removing the malware or virus. Chevymontecarlo 19:47, 7 January 2011 (UTC)

Sorry if I'm pointing out the obvious, but the advice from 174.21.250.227 implies that it is important to write a separate email to your friend, and not to reply to the email directly. That reply might go to the originator of the spamming scheme, and provide them with your email address. A follow-up question to the other refdeskers: might there be additional damage done by replying to such an email, like malware installation on your computer? --NorwegianBlue ^talk 10:23, 8 January 2011 (UTC)

Phew... I replied the email, and she said she did not send it. So (fortunately) it was not what 174 said. Thanks, everyone. Kayau Voting IS evil HI AGAIN 13:39, 8 January 2011 (UTC)

I don't think you understood what I wrote. The From: address on an email is exactly like a return address on a letter. Although most are labeled with the address of the person who sent it, there's not physical or technical prohibition that it *has* to be that way. If you know how to do it, you can substitute any address and any name, and the mail system will accept it without question. If her address was forged by a third party, your friend *wouldn't* have sent it.

The email system works like this: Your friend uses the email program on her computer to send a message through her email provider (ISP/Gmail/Hotmail/etc.), which then passes it through the internet, where it is accepted by your email provider, which sends it to the email program on your computer, where you read it. There's only a limited amount of security at any point in that path. At any point in that system, a third party spammer could break in an send a spam message. (1) They could install malware on her machine which sends the message without her. (2) They could hack into her email account, and send the message without her or any of her computers being involved. (3) They could spoof the from: address ("Hi Kayau's email provider, I have a message for Kayau from (friend)" "Okay, stranger who I have never seen before, I will trust that it's from (friend), even though you have no proof it is."), and send the message without her, her computers or her email provider being involved in any way shape or form. Due to the way the email system is set up, this can happen even if you use the same email provider. Mail systems will accept internet-originated messages even if the from: address indicates they should have originated internally. (4) Technically they could do something with your email provider/account/computer, but that's very unlikely. Most spam messages happen by (3). The spammer just inserts a random from: address so people can't track who's really sending the message, and doesn't have anything to do with the person who is supposedly "sending" the message. As you know her, it's likely the spammer is aware of the fact you email each other, so probably has her address book, which means (1) or (2) are more likely than (3) (but (3) is still possible).

Finally, the point of forging the From: address is that it hides who sends it. There isn't any secretly encoded "real sender" information, so if you do reply to the message, the reply will go to the account it says on the From: line, not the person who actually sent it. (Caveat, there is also a Reply-to: line, and if set, the reply will go to the Reply-to: address, rather than the From: address. This could be the real sender, but it would somewhat defeat the purpose of forging the From: address.) I can think of no practical situation where replying to an email will harm your computer. (If there are executable attachments, and you run them, that may infect/harm your computer, but most email programs shouldn't open attachments just because you reply.) Replying to spam is usually bad because by replying you inform the recipient that your account is active, but your message will only be sent to the addresses on the To: CC: or BCC: lines. If they're all people you know, the spammer has no way of receiving your message. (Unless he's hacked their computers/accounts, in which case he'll get all their messages, replies or new.) That said, composing a new message is not a bad idea, even in situations where replying is perfectly safe. -- 174.21.250.227 (talk) 17:18, 11 January 2011 (UTC)

TLDR of the above; Replying to the email, rather than writing a seperate email is a bad idea. If the reply-to field is set you would just have confirmed that your email account is live, and hence worth more to spammers. This can mean that your email account will receive more spam. Nothing bad actually happens on your computer, but it's not a desirable thing anyway. Taemyr (talk) 08:59, 12 January 2011 (UTC)

What would you learn after you learned how to program?

After you went through your programming 101, learning the syntax, how to use the libraries, etc, what would you learn? I thought that UML is nice (and relatively simple, at its most basic level), but what do programmers how want to improve their skills would need to know? (specially in the field of mathematics). —Preceding unsigned comment added by 77.231.17.82 (talk) 10:33, 7 January 2011 (UTC)

You need to learn about the hardware. If you don't have a firm grasp on the hardware, you will go off and write bad code. As an example, assume you just finished officer school in the military. Now, you're off to war. You could sit in your office and hand out orders without ever taking time to see what kind of troops you are ordering around. It would obviously be better to first find out what the unit is designed to do and what the troops' specialities are. Within a computer, you are ordering around all the components. So, it is a good idea to get to know what those are, how they work, and how to get the best effectiveness out of them. Since you are considering math-related work, you will want to know the ALU very well. I also suggest studying discrete mathematics and computer algorithms (P/NP algorithms) so you don't go off and try to reinvent work others have done over and over and over - such as coming up with yet another radix sort. -- kainaw™ 15:28, 7 January 2011 (UTC)

Well, I think there are a set of things. The single most important thing a programmer needs to learn is how to work together productively with other people, but it's hard to find a class that teaches that. I would say the second thing, beyond even a knowledge of hardware, is a knowledge of project-management tools, including version control systems such as SVN and Git as well as organizational tools such as GNU autotools. In the math realm, numerical methods are very helpful, besides the things that Kainaw mentioned. Looie496 (talk) 17:25, 7 January 2011 (UTC)

It depends very much about what you want to do. But for challenging work, algorithmics and basic complexity theory are very important - the first both to show you what methods are available, but also which techniques have been used to tackle hard stuff before, and the second to understand why you should care about good algorithms and data structures. --Stephan Schulz (talk) 17:35, 7 January 2011 (UTC)

re: "how to work together" classes... Every university that I've taught at has at least 2 semesters of required software project courses. They have different names from campus to campus, but the concept is the same. Start with the waterfall method and go through all the other popular methods of software development. Teach project management tools. Have students work in groups to complete a complex project (usually over the course of two semesters). -- kainaw™ 19:36, 7 January 2011 (UTC)

computer theory is an important next step. Other than that, CS programs in four year colleges are also usually heavy on the math. Calculus and Discrete math are usually covered. A Computer Architecture class and/or an Assembly Language class are probably in there too.

Students at four year schools tend to specialize somewhat within their degree. Students may have the choice of taking a certain number of credits in areas like databases, robotics, computer graphics, human-machine interaction, artificial intelligence, machine learning, etc.

IS all this strictly necessary? No. I'm sure there are people who make a good living having learned everything they needed "on the job", or from a "Learn iPhone programming in 30 days" type book.

One last note, while learning syntax is easy, I don't think that there is an "after you learned how to use the libraries". Any real world programming will require using a lot of different libraries from different vendors. Learning the libraries that "come with" your language of choice is only the beginning. APL (talk) 17:36, 7 January 2011 (UTC)

In most accredited university degree programs in computer science, the basic introductory course involves a class in each of the following areas:

• Computer programming basics:
  • a language primer ("Programming 101")
  • an advanced language course, ("Programming 201")
  • an algorithms and/or data structures course ("Programming 301")
• Computer science basics
  • discrete mathematics and computer-theory course
  • elementary computer architecture
  • Software engineering fundamentals
  • operating systems concepts

Beyond those classes, specialized fields of computer science, computer engineering, or software design can be pursued. Most reputable computer science programs also require extensive math training, in calculus, linear algebra, and often in differential equations. Here's a semester-by-semester breakdown from my undergraduate alma mater, North Carolina State University's computer science core curriculum. You can read a "blurb" / paragraph course overview for each of the required classes. These requirements are comparable to almost any other major university program for a Bachelor of Science in Computer Science. But you don't have to pursue "computer science" - maybe you learned to program so that you could become a mathematician, a physicist, an engineer, an economist, or any other type of career or academic track, you might follow a different route. If you like applied math, I highly recommend at least one or two solid classes in numerical methods, in addition to basic algorithms. Bear in mind that you will need to know some fairly advanced calculus in order to program a computer to compute even simple calculus correctly; the same goes for all other disciplines of mathematics. As a rule, programmers must be better at the mathematics than the machine, because they are giving instructions to the machine. Nimur (talk) 19:45, 7 January 2011 (UTC)

May I recommend Knuth's The Art of Computer Programming? It taught me all sorts of useful and interesting things, especially mathematical stuff, that my BSc in CS missed out. Marnanel (talk) 15:20, 8 January 2011 (UTC)

Task manager

If I go to the task manager on my computer, it gives to bar graphs, one for CPU usage, in percent, and the other is "PF Usage", measured in megabytes. anyone know what "PF" is? Something to do with RAM? --T H F S W (T · C · E) 19:44, 7 January 2011 (UTC)

Page file. Nimur (talk) 19:47, 7 January 2011 (UTC)

Thanks. How do I tell how much RAM my computer is using? --T H F S W (T · C · E) 19:57, 7 January 2011 (UTC)

Due to caching, the answer to that will likely be "all that is available". There is no benefit in having unused RAM. So, modern operating systems keep as much stuff in RAM as possible to avoid pulling it off the hard drive or recalculating it again in the future. -- kainaw™ 20:01, 7 January 2011 (UTC)

So in other words, almost all your RAM is being used at once, and the "overflow" is put on the page file? --T H F S W (T · C · E) 21:37, 7 January 2011 (UTC)

Yep. Of course, if your computer isn't doing much, the RAM may not be 100% in use, and the paging space will be empty. StuRat (talk) 22:17, 7 January 2011 (UTC)

On Windows, there is a special operating system file on disk, pagefile.sys, which is usually invisible. Certain portions of that file are mapped to RAM; the job of the Windows operating system's memory manager is to decide which portions, and when to swap them out. The value reported in Task Manager for "size" of the page file is not necessarily the size of the file-on-disk. (That's managed dynamically by this system setting, and varies between a minimum and maximum file-size). Task Manager is really reporting the total number of bytes that user-space programs have allocated. Those bytes may reside in RAM or on the disk in the pagefile.sys file; or in both places, with a caching policy managed by Windows. This Microsoft TechNet blog gives a good overview of the whole process. Nimur (talk) 22:36, 7 January 2011 (UTC)

January 8

Restoring a Windows XP user profile

I have a problem with a computer (running Windows XP), which is a member of a domain. After a system restore following by an undo of the restore, the user's profile is "lost". Actually it's not lost, it's still in the file system, but Windows has created a new profile for the user. When the user logs onto the domain, the user's settings are loaded from the new profile folder, not the previous one. It is in principle possible to copy the user's files from the old profile folder to the new one, but the pathname references in the user's application settings (whether in config files or in the HKEY_CURRENT_USER branch of the registry) will become invalid. What is a good way to restore the previous user profile folder for the user? —Preceding unsigned comment added by 173.49.14.169 (talk) 00:39, 8 January 2011 (UTC)

If you log in as an admin, you can use advanced system properties to copy user profiles from one user to another. This may do what you want.--Phil Holmes (talk) 11:27, 8 January 2011 (UTC)

3G

Is 3g as insecure as wifi? 62.255.129.19 (talk) 01:07, 8 January 2011 (UTC)

3G#Security; by default, probably not, but they both have the same potential security. ¦ Reisio (talk) 02:12, 8 January 2011 (UTC)

Eh, where am I?

This may be a supremely stupid question, but can the internets tell me where I am exactly? I am on a train and have absolutely no idea. Is there some service for triangulation of signals or some shit? 78.40.152.129 (talk) 09:00, 8 January 2011 (UTC)

Is Google Latitude what you had in mind? Dismas|^(talk) 09:04, 8 January 2011 (UTC)

Possibly, but seems to only work for mobiles? I'm working off a laptop... 78.40.152.129 (talk) 09:18, 8 January 2011 (UTC)

If you're using your laptop on a train, then it's using a mobile phone signal which can be triangulated. Another option would be to get a cheap GPS navigation device which is not dependent on a mobile phone signal.--Shantavira|^{feed me} 10:16, 8 January 2011 (UTC)

Most trains offer WiFi nowadays. Presumably the train gets it from a satellite connection or something, but I'm not sure you'd be able to geo-locate that.

Surely the best way to pin-point your position would be to estimate your speed and the time since you left the last station? APL (talk) 22:08, 8 January 2011 (UTC)

Congratulations, you made it to the UK in less than 4 months. -- 78.43.71.225 (talk) 22:09, 8 January 2011 (UTC)

What is Binary Package?

In many of the Linux distros, there are Binay Packages available to be downloaded. What are these Binary Packages? How can they be used? —Preceding unsigned comment added by 122.164.51.244 (talk) 09:32, 8 January 2011 (UTC)

Computer programs exist in at least two forms. They are generally written by humans in various specialised languages. This form is called "source code". It cannot generally be used directly by a computer. Then they are passed through another program called a "compiler" to produce code which can be used by a computer. This form is called "binary" (for historical reasons; it has little to do with the number base). Linux distributions are free software, which some call open source, and are therefore required to offer you not just the binary forms of the programs but also the source code. This is useful for programmers because they can modify the program to do what they want more exactly. If you are not a programmer, the binary packages are the only packages you are likely to need. Marnanel (talk) 15:12, 8 January 2011 (UTC)

You could be talking about a few different things.

There are distributionss whose package management systems are aimed at building of source directly to make the compiled, binary files for a computer to run (these typically exclude programs written in interpreted languages, but often not the interpreters themselves); source code is often distributed in some form of tarball, or copied directly from a VCS. This approach gives an advantage in the ability to customize, and availability of current code.

For most distros, however, the bulk of binaries are built by developers to ensure a certain quality/continuity, and then distributed to end users — they basically end up merely copying a program to where it should be on a system, and it's ready to run. This has the obvious advantages of being fast and reliable, particularly for those unfamiliar with compiling source code (which is most people).

Distros following either approach can utilize the other approach also, but usually only one is preferred.

There are also .bin files and the like, which are usually built and distributed by upstream and not by distribution maintainers, usually for the purpose of protecting a certain quality in their product, or because the package contains non-"free" parts, or for a perceived "ease" of installation, or any of the above, etc..

¦ Reisio (talk) 15:14, 8 January 2011 (UTC)

Video

I have a video encoded in h264 at 5fps. I need the video to be 25fps, but I want it to remain the same speed and duration. What Windows programs (preferably free) can do this? 82.44.55.25 (talk) 14:51, 8 January 2011 (UTC)

It sounds like you want to do tweening to fill in the missing frames. I can tell you right now that this isn't going to look very good, with 80% of the frames being made to fill in the gaps, because there's just not enough "information" to start with. I think 50% or fewer frames "tweened" in this way might look OK. StuRat (talk) 15:03, 8 January 2011 (UTC)

Yes, that's exactly what I want. I'm not too worried about quality 82.44.55.25 (talk) 16:15, 8 January 2011 (UTC)

FFmpeg can do this sort of video conversion. Graeme Bartlett (talk) 20:45, 8 January 2011 (UTC)

ffmpeg can adjust the frame rate of a video, but only by duplicating or dropping frames, not interpolating. In this case each frame would be followed by 4 exact copies of itself, so the result played at 25fps would exactly like the original at 5fps, not smoother. ffmpeg is too simple for such a complex job. 67.162.90.113 (talk) 22:28, 8 January 2011 (UTC)

You could use FFmpeg to dump to JPEGs (ffmpeg -i foo.h264 %d.jpg), then use ImageMagick (and a for loop) to make filler frames morphed from adjacent ones, then FFmpeg again to go from JPEG to <insert video format of choice>. ¦ Reisio (talk) 03:47, 9 January 2011 (UTC)

How to make a "clean link" to a video on youtube.com ?

Resolved

When I have found a really nice video at youtube.com, that I want my friend to see, how do I link to it in a "clean" way?

I want to send my friend a link to a webpage where the video may be seen, but I do NOT WANT want ANY of the "suggested further viewing"-links that youtube.com automatically adds around, below and following all the videos.
(What I have got is a URL looking like this:
http://www.youtube.com/watch?v=STRING
What I want is some "clean" URL based on the same STRING ).

The reason why I don't want it, is that I have no control over those suggestions and they will often totally destroy an otherwise pleasant viewing experience.
Or they may slightly frame the video in such a way that it distorts or adds a subconsciously perceived intention behind my sending of the link.
Is there any way out of this problem? --178.232.73.66 (talk) 18:22, 8 January 2011 (UTC)

There's an icon third from the right that looks like the traditional maximize window icon, if you hover over it, it says 'Pop out'. Also if you hit the 'Embed' button underneath the video, the value of the src attribute of the embed element or the value of the value attribute of the param element with name attribute with value 'movie' (they are the same/redundant) will work as a fullscreen link of the Flash player with video only. You will of course still get suggestions when playback finishes. ¦ Reisio (talk) 18:28, 8 January 2011 (UTC)

Like this http://www.youtube.com/v/QQrWTQBZPo4 Replace "QQrWTQBZPo4" with the video id of your choice 82.44.55.25 (talk) 18:30, 8 January 2011 (UTC)

Yes, (thank you!) a link on the form: http://www.youtube.com/v/STRING is very close to what I wanted, but I really want to avoid ALL the suggestions about further viewing that, now, still pops up below my video after it is finished runnig through the first time.--178.232.73.66 (talk) 19:11, 8 January 2011 (UTC)

I found a way; append &rel=0 to the end of the url, eg: http://www.youtube.com/v/STRING&rel=0 82.44.55.25 (talk) 19:20, 8 January 2011 (UTC)

Perfect! Thank you! :-) --178.232.73.66 (talk) 20:41, 8 January 2011 (UTC)

Restoring iPod touch Firmware without iTunes

Is there any way that I can restore my iPod touch's firmware to an arbitrary version, bypassing the SHSH signing process—in other words setting my iPod touch to any firmware version in such a way that iTunes is not used? --Melab±1 ☎ 19:31, 8 January 2011 (UTC)

QIF to CSV conversion

Is there any free straightforward offline (not online) no-hidden-catch way of converting the QIF format to comma separated values please? OpenOffice cannot do it. Thanks. 92.15.7.205 (talk) 20:37, 8 January 2011 (UTC)

Other than checking the obligatory http://www.google.com/search?q=%22qif2csv%22, this looks half promising (sorry if you don't Perl, you should! :p). ¦ Reisio (talk) 04:31, 9 January 2011 (UTC)

BBC

According to this one needs a tv license to watch live programs on the iplayer, per "Anyone in the UK watching or recording television as it's being broadcast or simulcast on any device - including mobiles, laptops and PCs - must, by law, be covered by a valid TV licence." That seems pretty clear, and the iplayer site warns you when you start to watch. However, what is the policy concerning the news section of the bbc site offering a live broadcast of breaking news, for example the live BBC News coverage of the US Congresswoman shooting? There is no mention on that page that one needs a license, nor is it part of the iplayer section. They're also enticing people to watch it with big banners across the news section saying "Watch live!". —Preceding unsigned comment added by 91.146.188.190 (talk) 22:30, 8 January 2011 (UTC)

Are you interested in knowing the policy, or viewing the programs? If the latter, there are so many ways to do so from anywhere, you need only seek out the solutions. ¦ Reisio (talk) 04:32, 9 January 2011 (UTC)

And if the former, we don't give legal advice... AndyTheGrump (talk) 06:51, 9 January 2011 (UTC)

It's not legal advice to ask why some policies look inconsistent, or to ask about the relative application of laws. There is no request for legal advice in the above whatsoever. --Mr.98 (talk) 14:46, 9 January 2011 (UTC)

I would imagine its because the iPlayer is available to UK users and people who pay a subscription outside the UK only, whereas the news site is available for free internationally. This requires different T&Cs. -- Q Chris (talk) 09:58, 10 January 2011 (UTC)

radiant

ben bu bılgısayar sıstemınızden sipariş vermek istiyorum ş yerım ıcın bana bu konuda yardımcı olur musunuz —Preceding unsigned comment added by 88.226.180.103 (talk) 22:53, 8 January 2011 (UTC)

Google translate (from Turkish): "Job I'd like to place an order for the location of this computer system helps me to do about it". Not very helpful... AndyTheGrump (talk) 23:00, 8 January 2011 (UTC)

http://tr.wikipedia.org/wiki/Ana_Sayfa. AndyTheGrump (talk) 23:03, 8 January 2011 (UTC)

Radiant Systems? 213.122.40.179 (talk) 01:44, 9 January 2011 (UTC)

January 9

Could intermediate networks alter my data?

If I do a traceroute to Wikipedia I see that the connection goes through several seemingly unrelated networks before reaching "ge-2-2.br1-knams.wikimedia.org". To simplify things for my question, lets assume it's just;

- myisp.org
- somenetwork.net
- wikimedia.org

I assume my http requests, ip address, and other info are sent to each link along the connection? What verification checks are in place (if any) to ensure that one of the links doesn't corrupt or alter the info either by accident or on purpose for some nefarious reason? For example, "somenetwork.net" receives my ip as 82.44.55.25 but sends my ip as 12.34.56.78 to wikimedia.org. Is such a thing possible? Would wikimedia.org see 12.34.56.78? 82.44.55.25 (talk) 22:05, 9 January 2011 (UTC)

Unless you use the https link to wikipedia there is no such guarantee. Dmcq (talk) 22:16, 9 January 2011 (UTC)

So if I owned "somenetwork.net" I could make it appear as though I had any ip address I wanted? 82.44.55.25 (talk) 22:28, 9 January 2011 (UTC)

You are making the assumption that your request and the response are all in one packet. See TCP/IP model for a better idea how internet traffic works. -- kainaw™ 22:31, 9 January 2011 (UTC)

Also see man-in-the-middle attack, which is what it's called when there's an attacker controlling some part of the path between you and the entity you're trying to communicate with. 67.162.90.113 (talk) 23:41, 9 January 2011 (UTC)

They could mess with your data just like food distribution companies could mess with your groceries. Your ISP pays a bigger ISP for bandwidth which it subdivides among its customers, that ISP gets its connection from an even bigger ISP, and so on. Eventually (usually very quickly) this tops out at the tier 1 network providers, which own the physical world-spanning cables. Your route to Wikipedia goes up your ISP chain to the tier 1 providers, then down Wikipedia's ISP chain to their datacenter. These big ISPs don't want to corrupt your data packets because that wouldn't maximize shareholder value. Whether somebody is eavesdropping on the connection is another matter; probably many governments have arrangements with the tier 1 providers to give them access to the traffic. -- BenRG (talk) 09:40, 10 January 2011 (UTC)

3g video calling architechre

hi,

i need to know about the 3g video calling with the call routing architecture. please let me know at the earliest. —Preceding unsigned comment added by 182.71.230.217 (talk) 08:18, 10 January 2011 (UTC)

how to Assign Structure Address

Hi,

I have doubt in C structure. That is how to assign structure address manually not default. Just i write one example structure,

struct ADC
{
 int A;
 int B;
}REG1,REG2;

when i compile the above structure defualt address in assigned like 8100,8101.. somethinglike that. I am using 16-bit processor. so that same code i want to use my address like 8000,8001,8002,8003... I know very well structure memory is stored in contiguous memory location. so that how to assign structure(ADC)starting address is 8000. Can anyone help me to solve this issue?

THANKS & REGARDS, M.ANTONY PRABHU

Try this:

struct ADC
{
 int A;
 int B;
} *REG1 = (struct ADC *) 0x8000;

-- BenRG (talk) 14:01, 10 January 2011 (UTC)

cmd capture

Is there an easy way to capture and save an image from a webcam via the command prompt in Windows? 82.44.55.25 (talk) 15:28, 10 January 2011 (UTC)

Number of unique colours in a digital photograph

I would like to identify which of these images http://www.google.co.uk/images?hl=en&expIds=0&xhr=t&q=flowers+spring+road&cp=18&um=1&ie=UTF-8&source=og&sa=N&tab=wi&biw=1024&bih=609 is closest to the original photograph. Inspecting them with Irfanview, they differ in their number of unique colours. Am I right in thinking that the image with the highest number of unique colours is most likely to be closest the original photo? I expect that when they are reduced in file size as preperation for including them on a website, the reduction in file size includes reducing the number of unique colours. Thanks 92.15.21.144 (talk) 15:35, 10 January 2011 (UTC)

Reducing the dimensions of a picture nicely (i.e. not using nearest-neighbour sampling) will potentially increase the number of unique colours, since nearby pixels are averaged, although it will also potentially decrease the number of unique colours simply because there are fewer pixels available to be any colour at all. Scaling a picture up nicely will likewise increase the unique colours, though it will be more blurry. These images are jpegs, and the way to reduce the file size of a jpeg is to increase the compression. In a palette-indexed image such a GIF or certain kinds of PNG, the number of colours can be reduced directly to make the file smaller. Jpegs don't work that way. They produce small file sizes for images containing smooth gradients, for instance. Their compression is achieved by reducing the level of detail (frequency) of the image. It might incidentally be the case that a more compressed jpeg contains fewer unique colours than a less compressed one, due to the loss of colours contained in some small details, but I wouldn't rely on it. 81.131.24.192 (talk) 16:02, 10 January 2011 (UTC)

I know this is nitpicking, but I believe the word you want is "distinct" or "different," not "unique." The word "unique" means "one-of-a-kind." —Bkell (talk) 16:47, 10 January 2011 (UTC)

You're absolutely right - that is nitpicking. :D Seriously, "unique" gets used that way all the time, and the OP is just quoting from a dialog box displayed in Irfanview. The colours are one-of-a-kind if we limit the context to the image. The opening words of Unique identifier are "With reference to a given (possibly implicit) set of objects ..." 81.131.33.9 (talk) 18:04, 10 January 2011 (UTC)

So the "number of unique colors" to quote Irfanview, not my choice of words, is not any use in trying to guess which jpg image has been the least mucked around with? I was thinking of suggesting the ratio number-of-different-colours divided by number-of-pixels as an approximate metric or proxy for the quality of an image, but that's out.

Is there any way of deciding objectively which is the least-blurred best quality image? Thanks 92.15.3.168 (talk) 20:27, 10 January 2011 (UTC)

Non-English glyphs in programming

Do they get any use? Plenty of common keywords (e.g. continue) are English, but does that mean the convention is to write in English throughout, even if you come from, say, Sweden, or would it be normal for such a programmer to name a function " räkna() " ? (I particularly want to know about the use of glyphs with diacritics, like ä, not the use of non-English words.) 81.131.33.9 (talk) 18:15, 10 January 2011 (UTC)

Either the compiler/interpreter can parse them or it can't. Easy to find out on your own. ¦ Reisio (talk) 18:16, 10 January 2011 (UTC)

That's not really my question - I'm asking about common usage. It's because I'm designing a font, and want to know whether to bother putting them in or not. Edit: actually I know what to do - of course they must go in, because even if they're not used in identifiers, they'll still appear in various string literals. (Mind you, I'm still kind of curious about the original question.) 81.131.33.9 (talk) 18:20, 10 January 2011 (UTC)

Yes, the convention is to write in English throughout, except in a few rare non-English-based programming languages. Marnanel (talk) 18:38, 10 January 2011 (UTC)

Actually, in my (admittedly rather limited) experience, programmers won't hesitate to write identifiers (and comments) in their native language, though they will omit the diacritics (because usually these are not allowed by the language specification). Source code intended to be publicly released to the wider world is generally an exception.—Emil J. 19:05, 10 January 2011 (UTC)

Fantastic find :) 81.131.33.9 (talk) 19:32, 10 January 2011 (UTC)

I'm not a programmer, but I do write some code occasionally, and I sometimes (but not too often) use my native language - for one thing, it is less likely that a given word I want to use have a reserved meaning in the programming language I use (which I tend not to be perfectly fluent in). But I never ever use native letters - I think most computer users from Scandinavia at least get used to replace the native letters (jørgen --> jorgen) because it leads to far less problems, even if the language / operating system supposedly supports them. There's always a complication someone hasn't thought of. For programming languages, it could for example be the encoding of the relevant text file. Jørgen (talk) 19:31, 10 January 2011 (UTC)

That's valuable anecdotal information, thank you. 81.131.33.9 (talk) 19:39, 10 January 2011 (UTC)

What is the efficiency of human sorting?

...or phrased slightly differently, what sorting algorithms do humans tend to use, and what are their efficiencies? I suspect the answer will depend a lot on the items that are to be sorted, so I'll present the example I'm particularly interested in, the sorting of sample tubes at a laboratory. The tubes are numbered (long numbers, say 9 digits). The numbers come in different series with the same three leading digits (six series, say), and may or may not arrive partially sorted. Sometimes they arrive in racks where each rack is partially sorted. I read the article Sorting algorithm, which states that a good algorithm has a complexity of ${\mathcal {O}}\left(n\log n\right)$ and a bad algoritm is ${\mathcal {O}}\left(n^{2}\right)$.

How will a human perform, in the setting I described? Guesstimates are welcome, pointers to relevant empirical studies even better.

Thanks, --109.189.66.11 (talk) 19:59, 10 January 2011 (UTC)

When I've taught algorithms class, I task 3 to 4 students with sorting short, medium, and long lists of items (sometimes numbers, sometimes words, sometimes sort on height or size). My experience is that humans use an insertion sort or bubble sort for short lists. When the list gets long, they tend to use a bucket sort to get it partially sorted and then an insertion sort on the shorter lists. There is a problem with identifying efficiency in computer standards. A human is capable of viewing more than one item at a time. So, insertion sort on small lists is O(n). For example, sort 4, 9, 2. You can see all three numbers at once and instantly note that 2 is the smallest. Then, you can see both 4 and 9 at the same time and note that 4 is the smallest. That leaves 9. A computer would have to look at each number, one at a time, to see that 2 is the smallest. Then, it need to look at the 4 and 9 separately to note that 4 is the smallest. If a computer was capable of looking at more than one number at once and perform a comparison on all numbers against all other numbers all at the same time (the way humans do), sorting would be much faster in computers. -- kainaw™ 20:23, 10 January 2011 (UTC)