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July 22

Rip off of the deleted website by the FBI

I heard there's a website containing survey when somebody downloads a file and it's a rip off of the old Megaupload website that was shutdown because of Copyright Infringement. It's called megadown.us that was not created by KimDotCom. Should wikipedia have articles about survey protected file hosting websites like FileIce or something like that?--HappyLogolover2011 (talk) 04:29, 22 July 2014 (UTC)

There's a large volume of such websites, and related, that are fading into, and out of, existence and usage all the time. Most are not in any way notable, nor do most have any pertinent sourced information pertaining to them. If one is the subject of media reports, and becomes notable, then that specific site might be worth adding an article on - or, perhaps, an article on the topic of such sites, if sources can be found - but, in general, there is very little compelling reason to give these sites articles.Phoenixia1177 (talk) 04:57, 22 July 2014 (UTC)

Some of the websites that has the contact button or whatever may not let us go to that page and find their info, but we can however trace the site's IP address.

Update: Fileice's IP address to the site is 66.252.2.22, the domain name that it uses is PROXYSHIELD.gigeservers.net and it was founded in Arlington Heights, Illinois.--HappyLogolover2011 (talk) 05:24, 22 July 2014 (UTC)

Not only is this information not really overly interesting on its own (as in, there wouldn't be much point to putting it in an article in the first place), but I don't see why this site, or any other like it, are notable enough to be included as articles. Is this site the subject of a news article? Several articles? etc.? If not, I see no reason this should have an article, is there a reason you believe it should? Finally, the reference desk really isn't the place to discuss this - to be honest, I'm not active enough on the other parts of Wikipedia to tell you what would be the place to discuss it, sadly.Phoenixia1177 (talk) 06:02, 22 July 2014 (UTC)

Wikipedia: Help Desk, probably. But no, nothing seems notable here. I wouldn't bother, Logolover. InedibleHulk (talk) 06:18, July 22, 2014 (UTC)

VoIP - two questions

I have two questions about VoIP:

1. When I use Skype, there is a long delay, almost as long as when they were talking to astronauts at the Moon. My landline has no noticeable delay. Does VoIP have that delay?
2. On my landline, I can talk and listen at the same time, as with a normal conversation. Does VoIP allow that, or can you only do one at the time? Bubba73 ^{You talkin' to me?} 07:29, 22 July 2014 (UTC)

Skype is VOIP. They are all different, and the delay can be dependent on the Internet speed of both participants, as well as any intermediary server that the VOIP is running through. Zzubnik (talk) 08:32, 22 July 2014 (UTC)

Indeed. I imagine some people with fibre connections and decent VoIP systems probably have lower average latency for medium distance calls (albeit neither being noticable) and probably longer ones too (presuming they're using a dedicated provider with decent routing, not just routing them randomly over the internet). And just because you're using your landline doesn't mean there's no VoIP somewhere in the system. I suspect in the modern world, the longer distance the call, the greater chance there's VoIP somewhere in the system. (Remember VoIP is just voice over internet protocol and has nothing to do with the internet per se.) Nil Einne (talk) 14:29, 22 July 2014 (UTC)

Not answers, but related comments:

1) Using satellites to communicate, especially the much farther out geosynchronous satellites, can cause this "satellite delay", as even at the speed of light, there's a noticeable delay in sending info that far. Undersea cables, on the other hand, are much shorter, and therefore faster. Of course, this all assume you are talking with somebody on the other side of the world.

2) Duplex (telecommunications) allows sending info both ways at the same time. However, you need a headset that isolates the speaker from the microphone, or they need to take steps to electronically prevent audio feedback. StuRat (talk) 12:34, 22 July 2014 (UTC)

No citations or sources, just based on my own experience:

1. I do not experience a delay when using VoIP (Skype in my case) between developed countries. I did experience a delay while calling home from the middle of nowhere in Africa though.
2. I've never noticed an inability to do duplex over VoIP - not even on a laggy line. If the line is lagging it can get confusing if both speak at the same time though.

WegianWarrior (talk) 14:30, 22 July 2014 (UTC)

Thanks to all of you. Duplex is the name for what I was talking about. In a traditional telephone, the mice and receiver are far enough apart so that feedback isn't a problem. The natural delay to and back a satellite is less than 0.25 second, but the delays now are longer than that. I've been Skyping to 800-900 miles away, and the delay is quite bothersome. Bubba73 ^{You talkin' to me?} 20:49, 22 July 2014 (UTC)

The path traveled by the signal might be far longer than the distance between sender and receiver. Both signals may go to a central hub, far away, and then sent on their way. Beyond that, there may be delays for processing the signals, and an overloaded system may put your signal in a queue until resources become available. StuRat (talk) 22:51, 22 July 2014 (UTC)

Processing definitely takes a long time. Back in the days of analog TV, when they would have a satellite hookup across the ocean, there wasn't nearly as much of a delay as there is now. And I can flip from a HD TV channel to its non-HD version, and the HD version is a long way behind the other one. Bubba73 ^{You talkin' to me?} 00:50, 23 July 2014 (UTC)

July 23

Editing from a Laptop

Recently I have been sometimes editing Wikipedia Dell laptop (Windows 8) with a mouse. It is frustrating. Sometimes, when I have an editor box open, I have tried to use the mouse and select text or to focus, and discover that a substantial amount of previous text (either my own or that of another editor) has blanked out. The only remedy that I have found if I have blanked another editor's text is that I have to leave the page. Restoring the deleted text would be harder than cancelling and trying again. My main question is: What can I do to prevent this blanking of text? This is one of two problems that I have that seem both to be due to the mouse focus moving. The other is having the focus change so that inserted text does not go where I had been entering it. What causes the mouse cursor to move, and what should I do about it? Robert McClenon (talk) 02:50, 23 July 2014 (UTC)

If the laptop has a touch-pad at the bottom of the keyboard - then probably you're inadvertently dragging your hand across it as you type. Both the mouse AND the touchpad are in control of the cursor - so this is an easy mistake to make. I don't know much about Windows 8 - but it ought to be possible to disable the touchpad somehow. SteveBaker (talk) 03:21, 23 July 2014 (UTC)

Thank you. Can someone else tell me how to disable the touchpad? Robert McClenon (talk) 03:55, 23 July 2014 (UTC)

My mom bought a Windows 8 Dell like that. The problem was it came with an unhelpful feature that made touching the trackpad click things, too. This might be what's happening when you think you're just selecting, but moving text out of the window instead. I think that was simply solved in the Control Panel, by unchecking a box ("Tap to click" or something). That's probably around where you'll find the option to disable it completely. InedibleHulk (talk) 05:10, July 23, 2014 (UTC)

I think that I have managed to disable the touchpad. At least I don't have the cursor moving randomly and eating things. Robert McClenon (talk) 05:38, 23 July 2014 (UTC)

Every laptop with a touchpad has a simple way of disabling it. On mine it is Fn-F8 (i.e., hold down the Fn key and press F8). Look over your function keys and see if you see a symbol that looks like a touchpad with a slash through it -- if so, that will be it. If it isn't there, look over the rest of your keyboard. Looie496 (talk) 15:00, 23 July 2014 (UTC)

Maybe I don't recognize any of the symbols as a touchpad with a slash. I disabled it from the Control Panel Mouse dialog. Robert McClenon (talk) 15:06, 23 July 2014 (UTC)

It might be a touchpad with an X in it Dell Instructions. ---- CS Miller (talk) 18:35, 23 July 2014 (UTC)

Thunderbird versions

Thunderbird just went from version 24.6 or 24.7 to 31.0. Why skip over major version numbers? Bubba73 ^{You talkin' to me?} 04:05, 23 July 2014 (UTC)

Firefox is currently at version 31.0. I suspect it was at version 24.x when Thunderbird was last updated. -- BenRG (talk) 04:14, 23 July 2014 (UTC)

Why do Firefox and Thunderbird need to have the same version numbers? I can see it with, say, an office suite, where you would want the individual programs to have the same version number. Bubba73 ^{You talkin' to me?} 04:16, 23 July 2014 (UTC)

Because version numbers give a certain expectation to users, so much that even completely unrelated softwares from different companies have jumped version numbers to "catch up" to their competitors, when they've upgraded to the same level of functionality. I can't remember the specific instance, i'm sure someone can chime in, but i think it happened in linux land where, for example, red hat who upgrade their software on a frequent basis made it to version 12 by the time some other linux flavor version only made it to version 6, but, that they were based on the same linux kernel and had essentially the same functionality, it's just that red had had performed their updates twice as frequently, so company B decided to release their "version 6" as version 12, since it was directly competing with red hat 12. Same thing probably happened here, thunderbird probably receives fewer updates as firefox, but it's based on the same technologies and is the same "generation" of software and has comparable security features etc... calling it thunderbird 24 when their flagship software is up to version 31 makes it "sound" like thunderbird is miles behind. Vespine (talk) 04:44, 23 July 2014 (UTC)

Thunderbird and Firefox are both based on Gecko. So, whatever version Gecko is, that is the version that both Thunderbird and Firefox will be. 209.149.115.166 (talk) 14:04, 23 July 2014 (UTC)

Thanks, Gecko must be this: Gecko (software). I didn't know they had so much in common, since their functions are so different. Bubba73 ^{You talkin' to me?} 21:48, 23 July 2014 (UTC)

Thunderbird 30 (...and earlier) were developer betas and were not marketed or advertised to the general community of users. From the developer mailing list archives, here is the May/June development plan for Thunderbird 31. If you subscribe to the developer feeds, or build your own Thunderbird from source - or if for some reason, you as an individual or organization have a special working relationship with the Mozilla development team - then you'll commonly have visibility into a lot more versions and forks than the well-advertised, widely-available, mass-announced general releases. But, the Thunderbird and Gecko code is still mostly open-source free software, so you can grab any version at any time. Nimur (talk) 15:09, 23 July 2014 (UTC)

Javascript function

Hi there, in Javascript I have a bunch of numeric variables, say a, b, c, d etc., and a procedure that takes any two variables, and changes both of them in a way that is dependent on both input values (for example, in a very simple case, a could become a + b, and b could become a − b). How do I create a Javascript routine to do this? I have a method at the moment that uses objects and "eval" statements, but it totally sucks, and it pains me to look at it. What is the elegant way to achieve this, given that I apparently cannot pass references to the numeric variables? 86.128.5.71 (talk) 11:25, 23 July 2014 (UTC)

Objects are passed by reference; so you can wrap those ints in objects, pass them, and mutations to their value are evident outside the function:

#!/usr/bin/nodejs

var add_and_diff = function (x,y) {
    var sum = x.val + y.val;
    var dif = x.val - y.val;

    x.val = sum;
    y.val = dif;
};

var a = {val:10};
var b = {val:20};
var c = {val:66};
var d = {val:99};

console.log('before:', a.val, b.val, c.val, d.val);

add_and_diff(a,b);
add_and_diff(c,d);

console.log('after: ', a.val, b.val, c.val, d.val);

Still kinda clunky, IMO. -- Finlay McWalterᚠTalk 12:31, 23 July 2014 (UTC)

Thanks. I think this is slightly better than what I currently have, but it still means in the main code I have to refer to "a.val", "b.val" etc., rather than just "a", "b", etc., right? I find this a real nuisance. 86.128.5.71 (talk) 16:56, 23 July 2014 (UTC)

You could copy the values out of the struct like this, after which .val cannot be used.

var a = 10;
var b = 20;

a = {val:a};
b = {val:b};
add_and_diff(a, b);
a = a.val;
b = b.val;

console.log('after:', a, b);

Another way to do it, which might be cleaner, is to return an anonymous struct, and then copy the values out of it. CS Miller (talk) 20:14, 23 July 2014 (UTC)

Thanks, yeah, I know I can copy "a = a.val", "a.val = a" etc. back and forth, but it really sucks. Could you give an example of what you mean by the "anonymous struct" method? 86.171.43.119 (talk) 12:59, 24 July 2014 (UTC)

I was thinking of C. In Javascript all structs are anonymous, as Javascript isn't strongly typed. I was meaning code like

var add_and_diff =  function (x,y) {
    var _sum = x + y;
    var _dif = x - y;
 
    return {sum:_sum, dif:_dif};
};

This allows the function to return two values at the same time. CS Miller (talk) 18:10, 24 July 2014 (UTC)

July 24

Burning CD

What is the problem when one tries to burn an hour music to an audio CD and when they are finished only 25 minutes have been burnt in?--85.74.103.132 (talk) 03:03, 24 July 2014 (UTC)

I think it has to do with it wanting to burn the CD at a certain rate, and if the PC can't supply the data at that rate it runs out of music to record and just records a blank from that point on. You can lower the speed at which it writes the CD, to try to prevent this. However the CD you already recorded can't be saved, unless it's an erasable CD. StuRat (talk) 03:39, 24 July 2014 (UTC)

Also, make sure the source is on a local hard disk, I've seen this happen if you try to burn directly from a USB key or from a network drive, or even another CD drive. Vespine (talk) 06:41, 24 July 2014 (UTC)

<tldr>What Stu and Vespine said.</tldr>

Earlier HDDs could not reliably provide the data fast enough for the CD-R drive, at least in borderline cases with fragmentation etc. Today, HDDs are faster than CD-R drives, by orders of magnitude. Even at 24x, that'd translate into 3.84MBps, and HDDs provide sustained data rates in the triple or high double digits. So, today, almost any write speed is safe from a data rate POV (but there have been reports that no CD-R can take more than about 25x reliably due to thermal limitations?), as long as the source is on HDD. If the source is somewhere else, like a CD, USB flash drive, network drive, or teh internets. No matter how fast your drive/connection is, most of these media can experience hiccups, during which no data are delivered at all. This can be enough to kill your recording session. - ¡Ouch! (^{hurt me} / _{more pain}) 08:57, 25 July 2014 (UTC)

Proof of concept: the WP database had a minor hiccup several minutes ago. It got better.

Actually, I don't think we can reliably conclude the cause from the information given. It's true buffer underruns use to be a common problem in the very early days of CDRs (I remember dealing with them). However this hasn't been a common problem for a long time. It's not just because of faster HDs, but because of Optical disc recording technologies#Buffer underrun protection which began to become common place in 2001? or so. These mean, unless you disable them or the software doesn't know how to use them (which again hasn't been a problem for a long time), the recording should not outright fail because of a buffer underrun. Because of the small gap such protection results in, it's possible some standalone audio players will have playback problems with the CD. Although because the lead-out etc was written, worst case scenario they should work if you skip the track if that is the cause (of course some have problems with many CDRs). Definitely even with the limited EC, the writer should at worst have a small hiccup when reading that track, and it's the same for many CD-ROM drives (so probably including anything which supports MP3 etc). Note also many software support a secondary computer RAM buffer, and if you have a 4GB RAM computer, the whole 800mb or so of a 70 min CD could easily fit inside the buffer generally without causing issue for anything else if you choose to size the buffer appropriately. (It may work on a 2GB as well but if you're more likely to have problems if running something with high memory usage.)

It could also be your software failed for some reason. Perhaps a key point, if there was a buffer underrun, or some other burning problem, it should have reported this (as a recording failure) and only take the time for the 25 minutes. If it didn't, this indicates the software at least believes it burnt the whole disk or it's such a POS you should never touch it again. (IIRC some software will try and write the leadout even after a failure to try and keep the CD readable, but it should still clearly report the failure.) It's not clear from the OP's comment whether there was actually a reported recording failure or the OP just found the CD wasn't the expected length after burning. If there was a failure, logs should provide some clue of what happened if it did fail. (If there wasn't a failure, logs may still provde some clues.)

There are many other things that could go wrong or cause a player to have problems with the CD if the recording didn't fail. As I already mentioned, standalone players don't always like CDRs. Similarly media compatibility varies quite a lot both between players and writers. Some like the famous gold Taiyo Yuden may be better on average. But still if you're writer does a poor job with them, it may be some other CDRs will be better. (And contrary to what some believe, burning at a slower speed isn't necessarily better. To be fair, I'm not sure 52x ever produces the best results, but many modern CDR and modern drives definitely aren't going to produce good results burnt at 1x either.)

Then there could be a variety of mastering issues (both software and user caused).

At the very least, if the time playback time is very different from the recording time, you should be able to tell by looking at the CD whether roughly the expected size was recorded or not.

Nil Einne (talk) 18:44, 25 July 2014 (UTC)

Lang subcodes case sensitive?

In some of my websites I use the language code <html lang="en-gb"> which normally seems to pass the various validation checks. However I have now come across Powermapper which objects to this coding. After some puzzlement, I worked out that it would accept en-GB, with the subcode in upper case. Is this actually required by the standards, or is Powermapper being excessively pedantic? --rossb (talk) 07:57, 24 July 2014 (UTC)

For HTML4, the spec says "Names of character encodings are case-insensitive". HTML5's spec points us to IETF's BCP47 recommendation, which says "At all times, language tags and their subtags, including private use and extensions, are to be treated as case insensitive: there exist conventions for the capitalization of some of the subtags, but these MUST NOT be taken to carry meaning". W3C's advice on language internationalisation says "Although the codes are case insensitive, they are commonly written lowercased, but this is merely a convention". The only place I see a requirement about case is where a document has both xml:lang and html lang= tags (where it's a transition from XHTML to HTML5) where the case is required to be the same in both formats. -- Finlay McWalterᚠTalk 10:38, 24 July 2014 (UTC)

hacking via php

I am a php beginner and on my first day my tutor hacked my gmail password using a small php script(approx 5 to 6 lines) and then he deleted it. i requested him to tell me for knowledge purpose but he didn't. i am wondering is hacking passwords so easy with php scripts?.i browsed on web but couldn't find anything reasonable. will anyone please clear that if something so easy exists in php or it was just a trick(may be he had some software installed on his laptop).182.18.179.2 (talk) 15:08, 24 July 2014 (UTC)

thanks for the reply Finlay Mcwalter, but i think i should have been more precise with the question the first time.actually, he wrote the code and saved in "htdocs" folder like normal procedure is and executed it in "localhost" then a page displayed with my username and password and he told that he had sent a request to "server".he also had a connection established to google and (through this) he tried to tell us that security depends upon coder's logic and not just this language is more secure and other not(between java and php here).182.18.179.2 (talk) 19:10, 24 July 2014 (UTC)

Things probably went something like this:

1. he copied the gmail login page (e.g. by downloading it with wget or curl)
2. he wrote a little PHP program that showed that page and waited for you to type your password
3. then he tricked you into accessing that site (maybe he just typed it in for you, maybe he messed around with the machine you were using to alter its DNS or proxy-server settings)
4. you didn't properly check that the connection was secure and signed by google
5. you typed your password in, and inadvertently sent it to his fake site

So he didn't hack Gmail with PHP, he hacked you with social engineering. -- Finlay McWalterᚠTalk 15:23, 24 July 2014 (UTC)

Well, Phishing to be exact. KonveyorBelt 16:24, 24 July 2014 (UTC)

As a general rule, one should never enter any kind of password into a machine that you don't trust (and for things that are really important - like banking - that you don't have total personal control over). He could have easily installed a keylogger, or could have altered the browser's settings (or its code) so that even if the site appeared to be an https connection properly signed by Google's certificate, it wasn't. -- Finlay McWalterᚠTalk 15:28, 24 July 2014 (UTC)

182.18.179.2, you should reply at the bottom of conversations, rather than at the top. It sounds like your teacher may have made a simple proxy server which does what I described above. -- Finlay McWalterᚠTalk 20:27, 24 July 2014 (UTC)

@Finlay Mcwalter thanks and i will take care of it from now onwards.182.18.179.2 (talk) 17:48, 25 July 2014 (UTC)

text 'Chapter # ' missing before chapter in latex

I do not know much about Latex. I have written a thesis with the help of a sample thesis. But i have some problems. For example, the name my thesis first chapter is 'Preliminaries', But in table of contents only 'Preliminaries' is written rather than '1 Preliminaries' and first chapter starts with 'Preliminaries' rather than 'Chapter 1 'in next line 'Preliminaries'. base class of my thesis is 'book', I m using class file with no preamble file. — Preceding unsigned comment added by 39.35.150.202 (talk) 16:08, 24 July 2014 (UTC)

We may need more information about how you've set up your work. How are you adding the chapters? I presume you're doing something simular to me and not writting one big long document in one file. In my thesis to get the behaviour you are describing I used

\addcontentsline{toc}{chapter}{Abstract}

\input{Abstract.tex}

which gives the Abstract and no number in the table of contents, but for the main section I used

\include{Introduction}

which give 1 Introduction in the table of contents (As I named the chapter the same as the file but you can have different chapter headings). Dja1979 (talk) 19:08, 24 July 2014 (UTC)

I assume that inside Introduction.tex you used \chapter{Introduction}? OP, just an off-chance, but did you use \chapter*{Introduction} (notice the star) in your thesis? --Stephan Schulz (talk) 07:00, 26 July 2014 (UTC)

That'll teach me for not looking at my code properly, I had the \chapter*{Abstract} in my Abstract.text. Apologies for not being more carful befor given advise.Dja1979 (talk) 17:27, 26 July 2014 (UTC)

Right or Left alignment of filenames in Windows7 folder?

I have an open folder in Windows7 with "View Mode" set to "details"-view.
Can I somehow get the filenames aligned to the right side instead of the standard left side of the column? Or toggle between Left and Right alignment of the filenames?
-- 46.15.238.85 (talk) 19:01, 24 July 2014 (UTC)

I doubt it. You'd need another application to do that type of thing for you. StuRat (talk) 00:31, 26 July 2014 (UTC)

But, Both Hebrew and Arabic script is written from the right to the left, and surely those language versions of Windows7 must have right alignment as a default. So there must be some kind of environment variable, somewhere, which governs the current right or left alignment — and which could easily be toggled — don't you think so?
-- (OP) 46.212.24.65 (talk) 21:50, 26 July 2014 (UTC)

Steelseries Apex keyboard media keys

I am interested in the Steelseries Apex keyboard, but I am concerned about the media keys to the right. According to some images on the Internet, there are previous/next track keys (|<<, >>|), while other images show rewind/fast forward keys (<<, >>) instead. I often use the previous/next track keys, but never the rewind/fast forward keys, so I am very interested to know what is actually the case. If the keys are the rewind/fast forward ones, can they be reprogrammed to act as previous/next track keys? --83.183.23.160 (talk) 23:08, 24 July 2014 (UTC)

The multimedia keys are standardized (at least de facto by Windows) and don't include rewind and fast forward, so I think that << >> is a variant labeling for the previous and next track keys. -- BenRG (talk) 04:56, 25 July 2014 (UTC)

Excellent. Thank you for your answer. --83.183.23.160 (talk) 18:35, 25 July 2014 (UTC)

Resolved

July 25

Search engine question. Ignore vs. exclude

Are there search engines which can do both, ignore and exclude?

I mean by "ignore", a search like (shades AND of AND grey) but ignore "50 Shades of Grey" should return most files containing the words "shades", "of", "grey" but only if they are not part of the wording, "50 Shades of Grey".

By "exclude", even a file containing both the wording "50 Shades of Grey" and the individual words outside the context would be excluded.

For example, the article would stay in the "ignore" results, because of the sentence "Not to be confused with Shades of Grey." but get excluded from the "exclude" search results, due to the redirect remark, "(Redirected from 50 Shades of Grey)". - ¡Ouch! (^{hurt me} / _{more pain}) 08:50, 25 July 2014 (UTC)

And again, the signature gained a second meaning.

I'm not sure of your distinction, but in Google, using -"some phrase", will ignore results containing exactly that phrase, for example searching for -"fifty shades of grey" -"50 shades of grey" shades of grey will ignore references to a certain BDSM-lite book and film. Note that both representations of 50 have to be separately ignored. CS Miller (talk) 11:12, 25 July 2014 (UTC)

pdf format

I cannot use all the functions in some pdf files (e.g. in Wikipedia article footnotes) on my new laptop, e.g. Search and Go To page number. Do I need to update some software in my laptop, and if so, how, please? I have Windows 7, IE11 and Firefox. --P123ct1 (talk) 11:21, 25 July 2014 (UTC)

If you access the PDF using a browser, the browser may display the file with any of several different PDF viewers, depending on your browser settings. I find Firefox picking different ways to display the PDF for reasons I can't fathom.

Once the PDF is displayed, see if there is a menu bar across the top with the choices "File Edit View Window Help". Click "Help"; see if there is a choice "About Adobe Reader XI". If there is, click it and make note of the version. Mine is 11.0.07. Let us know what you find. Jc3s5h (talk) 11:38, 25 July 2014 (UTC)

@Jc3s5h:There is no menu bar with "File Edit" at all, just "Print Save Share Create pdf using Acrobat". When I go to "Create using Acrobat", it calls up a screen asking you to buy Acrobat which will convert files to pdf, at £65 a year! I see I already have Adobe 9.5 in the laptop, but when I save the pdf file (from a Wikipedia footnote) to Adobe 9.5 and then use this new file, only the Go To page function works, not the Search function. I did this using IE11 and then Firefox, with the same result. Could you look at the Wikipedia file, please, and see if you can make the functions work? It is at Islamic State of Iraq and the Levant, footnote #142, "Senate Committee on Intelligence ...", which is a US government document. --P123ct1 (talk) 07:39, 26 July 2014 (UTC)

I have just tried some other pdf files from Wikipedia footnotes, and all the functions work perfectly, without any conversion to Adobe 9.5. It would be interesting to know if you have the same difficulty I had with the file I referred you to. I suppose it could be something to do with it being a very sensitive US government document (on terrorism) - there is a lot blacked out - but it is in the public domain, so I don't see why. --P123ct1 (talk) 09:10, 26 July 2014 (UTC)

When I click on the footnote in Firefox, on a Windows 8.1 laptop, it downloads the document into my Downloads folder. When I click on the Firefox download arrow and then click on the document, the document opens in Adobe Reader XI, as usual. So I think your problem has nothing to do with the footnote, it has to do with the way your computer and browser are set up. By the way, "Adobe 9.5" isn't a useful software designation, since Adobe sells so many different programs. You might be referring to Adobe Reader 9.5 or Adobe Acrobat 9.5. I think they also have some on-line versions of Acrobat, although I don't remember if they had an on-line version back in the 9.5 era. Jc3s5h (talk) 11:09, 26 July 2014 (UTC)

Sorry, yes, I meant Adobe Reader 9.5, and I have Windows 7. I have downloaded it the way you said you did with Firefox and it opens in Adobe Reader 9.5, but I still get the same problem, only the GoTo works, not the Search function - and as I said before, this only happen with this particular document, not other pdfs I have opened with IE11 and Firefox. They have all been in Adobe Acrobat, and only this one doesn't work. Very strange. P123ct1 (talk) 12:36, 26 July 2014 (UTC)

What do you mean 'search' doesn't work. Do you mean search doesn't find anything? Or you can even get it to open? If the PDF is an image rather than text and it isn't OCRed in the background, then searching won't find anything. For that matter, if it is text but they did one of those copy protection things where they used a custom font with custom mappings you'll have to know what to actually search for.

While there are numerous restrictions that can be placed on a PDF (look at the document properties in Reader to see what ones apply to your PDF) including disabling copying the content, printing etc; disabling searching isn't one of them. (If the PDF can be opened, these restrictions are more annoying than real restrictions. There are many ways around them although that may or may not fall afoul of the DMCA in the US.) And AFAIK, even if the PDF has absolutely no text, you should still be able to try to search, although I can't speak for Reader 9.5 in particular.

Nil Einne (talk) 13:57, 26 July 2014 (UTC)

P.S. I has a quick look and the PDF is indeed an image one without any apparent text. However attempting to search still works fine on Reader XI. It doesn't find anything, as you would expect. Nil Einne (talk) 14:02, 26 July 2014 (UTC)

@Nil Einne: The file opens in Adobe Reader 9.5 and the search box is there, but when I type in a word and press "Find next", it says it has searched but cannot find, so it does perform a search. I didn't know about the image thing, which explains it. Thanks. --P123ct1 (talk) 14:52, 26 July 2014 (UTC)

C Compiler on Windows 7 Desktop

I would like to run C programs on my Windows 7 desktop computer. What is anyone's advice for a compiler? In the 1990's the compiler of choice was Borland Turbo C for about $300. However, now it has been made into freeware. That would be fine if I could figure out how to complete its installation, but I can't. Some of the web sites that come up on a Google search for it then try aggressively to get you to download other software that I don't want and don't trust. The site that I think really is Borland downloads a ZIP file to me, which I can unpack, but it doesn't include instructions for what to do next. Is there a .exe program that will install the unpacked elements? Is there a set of instructions? I assume, with freeware, that there is no technical support. There are C compilers out there for $700, but that is a lot. Is there a reasonable commercial C compiler for $400 or less, or is there a web site that provides detailed instructions on how to install Borland? Robert McClenon (talk) 14:41, 25 July 2014 (UTC)

Microsoft Visual Studio Express is free, if you want to use it. If you want to use the Borland compiler, then WinZip or 7-Zip will extract the files for you, they are both free, but WinZip is nagware. CS Miller (talk) 15:41, 25 July 2014 (UTC)

Maybe I wasn't clear. I wasn't asking how to unzip the files. I did download the ZIP file and I did extract the files for Borland C. What do I do to install the compiler? All that the unzipping does it to create a folder of files. It doesn't install the compiler. Also, what does Visual Studio Express do? Will it compile K&R C, or does it do something else? Robert McClenon (talk) 16:11, 25 July 2014 (UTC)

What's inside the ZIP file? Is there an .exe? MS VS Express is a full C and C++ compiler, IDE, and Debugger, but the profiling and installer builder won't work (you need the paid-for versions for those). It appears to support K&R code, over ANSI. Why are you using K&R anyway, ANSI C gives you warning about incorrect parameters, and automatic casting. CS Miller (talk) 16:29, 25 July 2014 (UTC)

I will answer later whether there is a .exe in the files that were unzipped. (I am not in front of the desktop but of the laptop.) What does the installer builder do? Does it install the compiler, or does it create the install wizard that installs the compiled C program on someone else's computer? I don't need that feature. My real question was whether it would compile source code that had all of the power of K&R C (so that I can use the K&R blue book as my language bible). It is my understanding that the differences between ANSI C and K&R C are not significant. Robert McClenon (talk) 16:38, 25 July 2014 (UTC)

It does the later, allows your program to be installed else where. VS express is installed by a wizard. Unless you have good reason to use K&R, you'd be better using ANSI, as it will catch some common mistakes. CS Miller (talk) 18:03, 25 July 2014 (UTC)

Unless you have some ancient programs to compile that will only work on Borland C (16 bit segmented programs, TurboVision, OWL, .COM creation) you should not need, and shouldn't use, Borland C. The obvious choice for C development on Windows is Visual C/C++, as CS Miller has noted. Apart from that, there is GCC (you'd probably install the MinGW environment to get it and its toolchain) or you'd use an IDE like Code::Blocks, Eclipse, Netbeans, Bloodshed, or Qt Creator, which all use GCC too. C as described in the 2nd (latest, still very old) edition of K&R is (essentially) ANSI C (the older form, found in the even more ancient 1st edition, is very rarely seen these days). -- Finlay McWalterᚠTalk 17:00, 25 July 2014 (UTC)

So is Visual C/C++ consistent with ANSI C? Visual Basic is not the same as other Basic implementations (as if Basic ever were a standard language). I don't have ancient code; I want to write new code. Robert McClenon (talk) 17:16, 25 July 2014 (UTC)

Yes. Much more so than 16-bit Borland C, where you'll run into limitations of the memory model (segmented memory, FAR pointers) which correspond to nothing in K&R. -- Finlay McWalterᚠTalk 17:24, 25 July 2014 (UTC)

Am I correct that segmentation was needed to work around the limitations of the 16-bit architecture on the 8086 and 80286? Robert McClenon (talk) 23:35, 26 July 2014 (UTC)

Segmentation (in real mode) was needed to make the 8086 and 8088 look and feel more like their 8-bit predecessors to the software. It obviated the need to make program images relocatable (COM files supplied no relocation information and had a fixed load address (0x100) but the system was still able to load them at any physical address divisible by 16) and it facilitated the translation of legacy software Asmrulz (talk) 02:52, 27 July 2014 (UTC)

Visual C++ is Microsoft C/C++ rebranded by marketing after the release of Visual Basic. There's nothing Visual about it. -- BenRG (talk) 19:57, 26 July 2014 (UTC)

If I Google on Microsoft Visual C, I see, among other things, options to install Microsoft C++ Redistributive. Am I correct that that isn't what I want, because only permits me to run C programs compiled on someone else's machine if I don't have my own compiler? In that case, is Visual Studio Express what I want? It is described as a tool page, but a compiler seems like something that stands on its own and is not merely a tool package or part of a tool package. Robert McClenon (talk) 23:35, 26 July 2014 (UTC)

Yes, the redistributable is useless to you. You want either "Visual Studio Express 2013 for Windows Desktop" or "Visual C++ 2010 Express". The latter may be a smaller download and use less disk space. It also supports C, despite the name. -- BenRG (talk) 00:08, 27 July 2014 (UTC)

Since C++ is a proper superset of C, any compiler that supports C++ supports C. The compiler won't return an error just because there are no objects. Robert McClenon (talk) 03:24, 27 July 2014 (UTC)

Mostly true. There are a few weird contrived C constructs that won't compile in C++. You can come up with some by mixing C-style comments with C++-style ones, for example.

a = b//*This is a C comment*/ 2;

In C, this just sets a to b/2, but in C++, it sets a to b but is missing a semicolon. --Trovatore (talk) 03:40, 27 July 2014 (UTC)

There are much bigger differences than that. For example char *p = malloc(1234); is legal C but not legal C++ (C++ requires an explicit cast to char *). In C it's legal to use printf without including stdio.h, in C++ it's not. Also, C99 and C11 added many features to C that are not in C++ and probably never will be. Visual C++ 2013 appears to support compound literals and designated initializers (both C99 features) in C mode but not C++ mode. (C99 also added // line comments, so your comment-syntax example is no longer valid.) -- BenRG (talk) 05:12, 27 July 2014 (UTC)

The relationship between C and C++ is beside the point. The compiler operates in a different mode when compiling C or C++ (indeed, there are different modes for each of the C standards and the different C++ standards). You tell the compiler which mode to operate in (either explicitly at the command line, or it infers it from the source file extension). -- Finlay McWalterᚠTalk 13:10, 27 July 2014 (UTC)

Turning Off Scheduled Update on Laptop

I have a Dell laptop with Windows 8. Three days ago, it started telling me that it would restart in 2 days in order to apply updates. Yesterday, it restarted itself (without giving me a choice to delay it), but then the installation of the updates failed, and the process of the restart and the backing out of the updates took about 90 minutes. I have now used the Control Panel so that it now checks for updates but prompts me as to whether to apply them. However, it is again saying that it will restart in two days. I used the troubleshooter to correct one problem with the updates. My question is whether I can remove the cached updates so as not to risk another update failure, or whether is anything else that I can to do to avoid having another failed update. Robert McClenon (talk) 15:01, 25 July 2014 (UTC)

My guess is that it's smart enough not to reuse a cached update that failed. StuRat (talk) 00:28, 26 July 2014 (UTC)

I don't think so. Why is it telling me that it will restart in two days? Robert McClenon (talk) 00:44, 26 July 2014 (UTC)

That would mean it will try to re-download the update(s), not use the (possibly corrupted) cached version(s). StuRat (talk) 01:50, 26 July 2014 (UTC)

When it comes down to information processing (and not storing), what are the most basic units?

What are the 0s and 1s of information processing? OsmanRF34 (talk) 22:33, 25 July 2014 (UTC)

0s and 1s. AndyTheGrump (talk) 22:41, 25 July 2014 (UTC)

Information processing is not quantified in that manner. --  Gadget850 ^talk 23:55, 25 July 2014 (UTC)

I wonder if the original poster is thinking of Logic in computer science or Boolean algebra? Jc3s5h (talk) 00:00, 26 July 2014 (UTC)

I would still call a unit of data (that can contain only a 1 or 0) a bit, in any case. StuRat (talk) 00:22, 26 July 2014 (UTC)

Clarification: I was thinking what are the operations that cannot be broken down further. OsmanRF34 (talk) 08:00, 26 July 2014 (UTC)

One is theoretically enough. Asmrulz (talk) 12:38, 26 July 2014 (UTC)

See RISC. StuRat (talk) 22:46, 26 July 2014 (UTC)

Depending on exactly what you mean by an operation, you might be interested in the Turing machine article. If you mean what are the simplest operations needed to implement an arbitrary operation on two bit strings to yield a third bit string, it suffices to be able to perform these operations:

• COPY a bit from input to output
• INVERT a bit
• output a 0 regardless of input
• output a 1 regardless of input
• AND (two inputs)
• OR (two inputs)

Strictly speaking, it isn't necessary to have both the operations AND and OR; only one of the two is really necessary. A book on combinational logic will confirm this. Jc3s5h (talk) 23:45, 26 July 2014 (UTC)

Maybe NOR logic or CMOS is what you're looking for? -- BenRG (talk) 07:00, 27 July 2014 (UTC)

July 26

Android app for photographing paintings and other rectangular items

I like to take photos of paintings at art museums with my Android smart phone, when that is allowed. Currently, I use the HTC One (M8). If the photos are good, I like to upload them to Wikimedia Commons and add them to Wikipedia articles. Often, though, the image of a painting is not a true rectangle, but rather a quadrilateral with sides that are not exactly parallel. I am looking for an Android app that would allow me to click on the four corners of the image, and stretch or skew it into an exact rectangle. Any suggestions? Cullen³²⁸ Let's discuss it 04:39, 26 July 2014 (UTC)

If you don't have to use Android, I recommend Hugin. If you do have to use Android, there are photo editing apps that do this. com.iudesk.android.photo.editor is a popular one, but it's adware, and I suspect it will do lower-quality resampling than Hugin, and won't correct barrel/pincushion distortion. -- BenRG (talk) 19:45, 26 July 2014 (UTC)

July 27

How much battery does enabling C-States save?

I'm using a Dell Latitude E7240 ultrabook with an 1.7 Ghz i3-4010U, 4 GB RAM, 128 SSD, Windows 8.1

The laptop has C-States enabled in the BIOS by default. However, when my computer is not in "High Performance" battery mode, or if it is not connected to Wifi, I hear a really annoying, sporadic whining sound somewhere from the laptop. Looking online, I have nailed the sound to what I believe is something known as "coil whine." It is a high-pitched pizoelectric buzzing sound.

I went into the BIOS and disabled "C-States" and the sound has appeared to have gone away.

However, since I plan on using the ultrabook as portable device, I am worried about negative battery life implications this may have. Does anyone have any rough ideas on how much disabling C-States will adversely affect my battery life?

Thanks. Acceptable (talk) 03:53, 27 July 2014 (UTC)

Do you mean how long a the maximum charge will last, or are you concerned about degradation of the battery to where it will no longer hold the maximum charge ? StuRat (talk) 13:20, 27 July 2014 (UTC)

I'm concerned with how long a maximum charge will last. By checking the predicted battery life by moving my mouse over the battery icon, it does seem that enabling C-States does increase the battery life by a few hours. But how accurate is this? Acceptable (talk) 15:55, 27 July 2014 (UTC)

Probably more accurate than any estimate we could provide. OF course, you can do the full test and see how long it takes to run the battery down with and without C-States enabled, while doing the same thing both times. StuRat (talk) 19:37, 27 July 2014 (UTC)

Budget desktop PC recommendations

My HP/Vista is taking about 5 min. to boot and periodically freezes for a minute or two (CPU usage shoots up to 100%), so I'm looking for a replacement for about $500-600 Canadian (no gaming, just the basics). Any ideas? Future Shop is offering a Dell i3847-5387BK PC (Intel Core i5-4460 / 1TB HDD / 8GB RAM / Intel HD Graphics / Windows 8.1) for $570. Clarityfiend (talk) 09:55, 27 July 2014 (UTC)

It would be cheaper just to wipe it and start again on the same PC. Do you have the install or restore disk? Does it have Recovery option, which will restore Windows to its initial state from a hidden partition? CS Miller (talk) 10:24, 27 July 2014 (UTC)

This sounds to me like a software problem rather than a hardware problem. The solution probably isn't to buy new hardware, especially when that hardware is low end. The solution is probably to look at what unused programs are starting automatically at boot and which programs are over-utilizing the CPU. Also, I'm more interested in the specifications of the machine you have rather than the computer you would like to buy. Any computer you buy from Dell, HP, Toshiba, etc., will have bloatware installed on it that will slow the computer down. No matter how cheap the hardware in your PC, it should never take five minutes to boot. It doesn't just "wear out" inside and slow down mechanically. That's not normally how PCs work.—Best Dog Ever (talk) 12:02, 27 July 2014 (UTC)

One case where it might take 5 minutes to boot is if it's set to do a disk scan (check all the hard disks for errors) on boot. You can usually skip this by hitting a key on the keyboard, or you can disable it entirely. I normally only let the scan run when I'm not in a hurry or suspect a disk problem. StuRat (talk) 13:10, 27 July 2014 (UTC)

Windows doesn't run chkdsk by default. If it detects file-system corruption, it may run once and then start up normally from then on. If it's always running on bootup, then there's something wrong with the hard drive. This is very rare.—Best Dog Ever (talk) 20:26, 27 July 2014 (UTC)

I agree with the advice to re-install the operating system and go from there. If there are things on there you want to keep, another option is to get a new hard drive, install the O/S on that, and keep your current hard drive as a non-boot drive. If you're not able to do that yourself, you can have somebody do it for you for a fee.

Something else you might want to try first is some scans for malware. That is junk that they sneak in with downloads that does nothing useful but uses up resources on your PC. Products like Ad-Aware will remove such cruft. StuRat (talk) 13:16, 27 July 2014 (UTC)

StringBuffer Object Concatenation in java

While creating an object of StringBuffer class we get 16 addtional character memory space along with regular data and the modification on the object takes place in the same memory space. so i tried a scenario to clear my doubt, i concatenated a stringbuffer object say("catty") with another stringbuffer "tftwvdhwgdddghdbshgsyg" (more than 16 character long) to see the capacity of the Stringbuffer object but every time i get the capacity as 46(whenever the another one is more than 16 character long). i had thought of getting an error for concatenating a string more than 16 character long.i also want to know the way for printing the address of stringbuffer objects.will someone please explain this(doubt) ?(i am using jdk 1.6).182.18.179.2 (talk) 14:31, 27 July 2014 (UTC)

The point of StringBuffer is that it is elastic; if you try to add more stuff to it than it will currently accomodate, the buffer is resized. The documentation says "If the internal buffer overflows, it is automatically made larger." Although the internal implementation does eventually use an array, as a user of StringBuffer you can mostly forget that. -- Finlay McWalterᚠTalk 15:05, 27 July 2014 (UTC)

thanks again ,but what about the capacity() always showing 46 and please tell me the method to print the address.with normal objects we just pass them in SOP to get their address.what to do with SOP as same process here prints the value contained in objects.182.18.179.2 (talk) 18:05, 27 July 2014 (UTC)

Java isn't C - you can't print the address of objects (unless you write some C); the addresses of objects is an implementation detail, which you shouldn't (and essentially can't) rely on. Printing a java.lang.Object prints its hashcode, which in some implementations may be the address - but this is an internal detail. Similarly, the specification for StringBuffer makes no guarantees about how much capacity it uses; it only promises to make sure there is enough. Different implementations will use a different strategy to decide how much to reserve. It's very rare for you to need to know the actual amount of capacity that is used; APIs to set and query this are provided for people who need to perform microoptimisations in this regard - in 99.9% of cases the defaults will be fine for you, and worrying about the capacity is a waste of your time. If you really care, pull the source for OpenJDK and read the source for expandCapacity in AbstractStringBuilder.java. -- Finlay McWalterᚠTalk 22:07, 27 July 2014 (UTC)

WYSIWYG editor adding local reference

I maintain my web pages with the free WYSIWYG editor KomPozer version 0.7.10 (20070831). The files on one site have the structure header + main + footer. The header file includes expressions such as

src="images/h_home1.gif"

But when I load a file into KomPozer, after the merge the expressions have had a local reference added,

src="file:///C:/Users/Hal/Documents/My%20Web%20Sites/images/h_home1.gif"

Obviously, the .gif then does not display correctly on the web site unless I manually remove 7 instances of the added text.

What is happening? Is there any way I can prevent this from happening? Is there a better free WYSIWYG editor? (On another computer KomPozer did the same thing, and so I used Microsoft Front Page, which I can’t install on my present computer.) --Halcatalyst (talk) 16:05, 27 July 2014 (UTC)

• That's KompoZer. --Halcatalyst (talk) 19:14, 27 July 2014 (UTC)

• Perhaps you need to fully qualify where it should find the "images" directory, if not on your PC. I'm not quite sure how you would do that in KompoZer, but I suspect the URL or IP address of the server would be part of it. If, on the other hand, the "images" directory should exist on each user's PC, then it should probably have something like "$HOME" at the start of the string. StuRat (talk) 19:31, 27 July 2014 (UTC)

• The images directory is a subdirectory of the directory where the main HTML file resides, as it is on the web server. I don't know what $HOME is or what it is used for. Is it part of HTML? --~~

Turning the scroll bar on permanently

I have no idea why but on one mac I use, as opposed to others (and it appears regardless of which browser I am using, or at least in both Firefox and Chrome), the scroll bar on the right side of the page only appears when I place my cursor there, winking off when not "in use", rather than being a permanent feature when visiting any webpage that goes below the bottom of the screen. I dislike this; I want to make it permanent, like it is on the other macs I use. This mac runs OSX 10.8.3 and the Firefox browser I mostly use is the latest version and has been updated many times so this scroll bar feature seems unrelated to the browser version. Any help with how I can set this to off, or whatever is needed to stop this behavior? (By the way, one of the reasons I dislike is that it often doesn't even work, I have to fiddle with my cursor on the side and clicking there before the scrollbar even appears.) Thanks--108.14.111.128 (talk) 20:25, 27 July 2014 (UTC)

Go to your System Preferences > General > Show Scroll Bars > Always That should take care of it. Dismas|^(talk) 20:45, 27 July 2014 (UTC)

Thanks so much Dismas. One of those things you either know where it is or you don't. No idea how it got turned off.--108.14.111.128 (talk) 22:16, 27 July 2014 (UTC)