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September 20

Open source calculator that looks like a real Texas Instruments calculator

What software calculator has the closest look-and-feel to a real hand calculator like a TI-83 or the TI-84? For a picture look at the TI-83 series. I know that there are better alternatives to perform calculations using a laptop. Sagemath is an example, among others. However, I am interested in getting used to the calculator allowed at many examination, not at the calculation result properly. --Scicurious (talk) 00:00, 20 September 2015 (UTC)

I have heard good things about Wabbitemu [ https://wabbit.codeplex.com/ ]. According tto this PDF page, it runs a downloaded image of the code that runs on the actual TI calculator, so everything should act the same, including any bugs (you don't want to discover that your calculator has a bug that your emulator doesn't while taking an important test!) A web search also turns up TilEm [ http://lpg.ticalc.org/prj_tilem/ ] and jsTIfied [ https://www.cemetech.net/projects/jstified/ ]. I tried Virtual TI a long time ago and was not impressed, but maybe there is a newer version that is better.

Please come back and update this with the results of your experiences with the above emulators so the next person can benefit from your experience. Thanks! --Guy Macon (talk) 01:36, 20 September 2015 (UTC)

Windows 10 - msconfig

In Windows 10, msconfig, General tab, I select the radio button for "normal startup", but it won't save it (even if I Apply or OK). It always goes back to "Selective startup", with a square in "Load system services", a check in "Load startup items", and a check in "use original boot configuration", the latter of which is disabled. Is this normal? Is it OK? Bubba73 ^{You talkin' to me?} 05:22, 20 September 2015 (UTC)

I just tried it and I'm experiencing the same behavior. Sounds like a bug. Do these instructions help? www.ehow.com/how_7390089_repair-msconfig.html A Quest For Knowledge (talk) 14:59, 20 September 2015 (UTC)

For some strange reason, ehow.com is blacklisted, so I had to remove the http:// from the URL. A Quest For Knowledge (talk) 15:00, 20 September 2015 (UTC)

eHow is a low quality content farm which outsources writing to anyone and rewards those authors on the traffic they pull in - see MediaWiki talk:Spam-whitelist/Archives/2010/08#ehow.com. -- Finlay McWalterᚠTalk 15:33, 20 September 2015 (UTC)

Sure, if you're using it as a reliable source in article space. The filter should be smart enough to distinguish between article space and the Reference Desk. A Quest For Knowledge (talk) 15:53, 20 September 2015 (UTC)

You can request a whitelisting for the RD if you want. I myself have occasionally used eHow, however it's something I avoid for reasons besides the blacklist. Anyway I think you're missing the point of the blacklisting which is to discourage spammers, no matter what part of RD they target. Whether spammers are likely to target the RD is hard to say. Nil Einne (talk) 16:21, 20 September 2015 (UTC)

Ammm, two humans I know who returned to 'Windows 7' because 'Windows 10' is not compatable with certain things. -- Space Ghost (talk) 18:26, 20 September 2015 (UTC)

Those instructions don't seem to address this problem (except I'm not sure if it is a problem, I haven't seen any ill effects). Bubba73 ^{You talkin' to me?} 05:22, 21 September 2015 (UTC) do a search on search engines using syntax "windows 10 msconfig" — Preceding unsigned comment added by 2A03:2880:3010:BFF6:FACE:B00C:0:1 (talk) 17:57, 22 September 2015 (UTC)

Am I making a hash of this idea?

This could be under Computing or Math. Computing wins (unless y'all don't agree).

I'm looking to host a collaborative project, where each user can choose to remain anonymous. However, I'd like to have a system whereby those who chose the anonymous route can later change their mind.

Let's take Wikipedia as an example. Anyone can anonymously add something or make a change, and there's no reasonable way to find out who they are.

If, in the future, an editor, for reasons of their own, decided to claim credit for a particular edit, there's no way for that editor to prove that they're the one who made that edit, if they were originally anonymous.

I've heard of trapdoor functions. I'm wondering if it's possible and/or reasonable to use these for this project.

My idea is that each time the user contributes, they include a whichamacallit (hash?), which is the product of two numbers. They keep those two numbers secret until such time as they wish to let people know that they were the contributor. My (limited) understanding of the trapdoors is that if they know the two numbers, that's almost incontrovertible proof that they are the perpetrator.

Is this idea feasible? Not having a lot of computer smarts, or knowing a whole lot of math, how would I implement this, without investing a lot of (or any) time or money for what I'm sure has been done.

Please keep in mind that I'm NOT suggesting that this is a good idea for Wikipedia. That's just an example that I feel more than a few readers are passingly familiar with.

Also, there's no need for super-security for my intended use. I'm not worried about a super-power breaking through the users identity.

Thanks for any help or ideas you might come up with. Bunthorne (talk) 21:40, 20 September 2015 (UTC)

Yes, user should submit a hash of their identity and contact information.

For example, in Linux I can type

khan@ToshiK:~$ echo 3dcaddy | md5sum
6a8d1f3d555c1ab285ec66854d15c4eb  -

Reverting 6a8d1f3d555c1ab285ec66854d15c4eb to 3dcaddy is quite difficult.--3dcaddy (talk) 21:57, 20 September 2015 (UTC)

@3dcaddy: sorry to interject like this
echo adds a newline by default, so your example isn't hashing the 7 ASCII character sequence "3dcaddy" but the 8 ASCII character sequence "3dcaddy\n". Use echo -n to suppress the newline, which yields the correct md5sum 5d1c09823512e0aee5080c5858968945 -- Finlay McWalterᚠTalk 14:50, 21 September 2015 (UTC)

Yes, that's right. The OP could also put everything in a file, and run "md5sum file".

Thanks for the quick response. I didn't realize it could be that easy. Unfortunatly, I don't do Linux (although I realize I should). Is there an easy way to do it with windoze? Bunthorne (talk) 22:06, 20 September 2015 (UTC)

Never mind. I did a quick search on "md5", and found a bunch of answers. Thanks for the tip. Bunthorne (talk) 00:32, 21 September 2015 (UTC)

I had marked this "resolved", but removed it since some of the responses brought up other questions. See below Bunthorne (talk) 20:23, 21 September 2015 (UTC)

One thing to bear in mind is that the high speed GPUs (edit: also ASICs, although only people with a specific goal in mind tend to have these) can compute certain hashes like MD5, combined with their popular usage to store passwords in some circumstances means that coming up with the reverse for a short string hash can actually be fairly trivial, even just an internet search. This didn't work with 3dcaddy (if we ignore this page), but would have worked with "bebopjazz1" [1] (random example I came up with when searching for something) or "BillGates" [2] and yes, even Bunthorne [3] [4].

If you get people to use a salt, you'd eliminate rainbow tables, unless people get interested enough in your website to develop a rainbow table for it (as I assume you'd need to use a fixed edit: known salt), but still won't eliminate the GPU problem.

If we assume most people are only going to be hashing their name or some pseudonym and most of these don't have numbers, and so only use upper and lower case letters and perhaps space and underscore, I suspect up to 11 characters may be feasible for someone without that much more resources than a dedicated gamer. ([5] is a little old and doesn't have exactly what you're looking for but is close.) It gets even worse if we decide it's most likely a real name from the Anglophone world or something of that sort. (Similarly if you're only using numbers, probably something like 18 decimal digits could be feasible.)

You'd generally want people to include at least 20 characters IMO and make sure it's more than just a name, maybe 30 or even 50 to be safe considering possible future advancements. An alternative (edit: or perhaps combined with a decent sized string) is to use a hash designed to be slower on GPUs edit: (and hopefully ASICs) like bcrypt or scrypt, although I'm not sure how well cryptologically tested these are.

Also due to the nature of hashes, people will have to record or remember exactly what their original string was including cases etc. Okay you could make a brute forcer for them, if they have a good idea of what it is, but that would complicate things somewhat. (Sufficient info would also reduce possible disputes if person A claims the hash represents them and person B who were the first to say it was them must have somehow reversed it.)

Nil Einne (talk) 07:38, 21 September 2015 (UTC)

Just as a historical note: in science there is always a conflict between wanting to publish an imporant new result in order to ensure you are recognized as being the one who discovered it, and wanting to investigate further in order to produce a more complete report. These days, as I understand it, scientists will first publish a short letter summarizing their finding and follow it later with a full paper. But centuries ago, what they did first in this situation was to publish an anagram of their result, and then when they were ready to do a full report, they would provide the explanation to the anagram. See anagram#Establishment of priority for examples. Of course if they were being tricky it was always possible that the same letters would anagram to more than one relevant sentence, saying different things! --174.88.134.156 (talk) 03:39, 21 September 2015 (UTC)

In the modern publish or perish environment of academics, it is very common to turn everything into multiple publications. For example, I had an idea that I thought was obvious. Everyone I spoke to said it was not obvious and apparently wrong. So, I implemented it and demonstrated that it worked. Then, I published a summary of the background information (summary papers are popular for textbook chapters). Then, I presented/published the general idea at a conference. Then, I published my findings. All together, the time between the summary paper and final publication was three years. So, I had three years to publish final findings while still demonstrating the work with the initial publication as a "guess what you can do with this knowledge" part of the summary paper. As an aside - I also take part in the "publish every paper as many times as possible" method of publication. For example, a paper on track management of hard drives became a paper on track management of radars, which became a paper on track management of cell towers. I'm now working on a paper for track management for a multi-signal bus in a cell processor system. 209.149.113.66 (talk) 11:50, 21 September 2015 (UTC)

It depends a little on how anonymous you want the edits to be. Using a hash of a secret (as proposed above) is fine if you want to know that one person made a set of edits, but not know who the person is. If you want stronger anonymity, where you don't know who made each edit, and can't tell which edits are made by the same person, then you need to include something unique into the hash. If this unique element is public, then it's still possible for the person to verify that they made that edit. For example, the content of the edit, or the time at which the edit was made could be added to the secret and then hashes (e.g. if I choose a secret of "Dave1", then a hash for this edit could be generated from the string "Dave1-10:40, 21 September 2015 (UTC)", and there would be no way of linking this to my next edit without knowing the secret). MChesterMC (talk) 10:40, 21 September 2015 (UTC)

Thanks for the great responses. As usual, the answers caused me to think of more questions.

Would making multiple hashes for the same data (with minor changes) make it easier to break the hash? For example, suppose I used the following inputs:

my email: foo@bar.com

My email: foo@bar.com

Contact foo@bar.com

foo@bar.com

Neglecting the fact that these are somewhat short, would using all of these at different times make it easier to extract the "foo@bar.com?.

How easy would it be to generate a different input to give the same output. This would be to enable "Plausible deniability" in the event that someone broke the hash, and tried to pin it on me when I don't want my identity known. Bunthorne (talk) 20:23, 21 September 2015 (UTC)

Yes. If you have a series of hashes, there is a higher chance that one of them could be reversed. But this is hard.

Finding a different input that reaches the same output is hard, but possible. md5sum is not completely safe against tailored attacks for people with sophisticated resources.

Still, just ask anyone to put name+email+some random text into a file and run "md5sum file." Let them generate different hashes with different random texts. That's pretty safe.--3dcaddy (talk) 00:10, 22 September 2015 (UTC)

Amazon ID

Does amazon (I use amazon.co.uk) have a unique id for each product? If so, how does one find out what it is and how does one enter it into the system to go to that item? -- SGBailey (talk) 23:35, 20 September 2015 (UTC)

Amazon Standard Identification Number. Vespine (talk) 01:57, 21 September 2015 (UTC)

If you go to the product page and scroll down to the box marked "additional information" you will see the ASIN. You can enter any ASIN in the Amazon search box to find any item.--Shantavira|^{feed me} 07:52, 21 September 2015 (UTC)

Thanks. That is sort of what I expected. It appears that for books the ISBN number is the ASIN. Amazon's help says "You can search for an ISBN or an ASIN in our catalogue. If you know the ASIN or ISBN of the item you are looking for, simply type it into the search box (which can be found near the top of most pages), hit the Go button and, if the item is listed in our catalogue, it'll appear in your search results". So to test I copied B00P6JZ4UQ from a (uk) pair of shoes, went to the homepage, pasted it into the search bar and pressed the magnifying glass (presumably "search") (there is no "Go" button). And behold, I get "Your search "B00P6JZ4UQ" did not match any products". Is it them or me? -- SGBailey (talk) 21:52, 21 September 2015 (UTC)

Amazon doesn't find B00P6JZ4UQ for me either, but you can just use google, search for amazon B00P6JZ4UQ, that worked for me: http://www.amazon.co.uk/Clarks-Smart-Huckley-Spring-Leather/dp/B00P6JZ4UQ Vespine (talk) 22:49, 21 September 2015 (UTC)

September 21

Screen Reader shares…

Hello,

Some features in ʜᴛᴍʟ like ᴀʀɪᴀ are not directed to be supported by web‑browsers but by screen readers for blind people.

When I search if a feature is supported by screen readers, I see various lists.
However this doesn’t help because I have no idea about the traffic coverage, even for the English language.

Would it be possible to find such shares ? 2A02:8420:508D:CC00:56E6:FCFF:FEDB:2BBA (talk) 00:05, 21 September 2015 (UTC)

When it comes to Internet applications for the blind, you will likely not find anyone who knows more than Bryan Smart. I'd ask him directly. 209.149.113.66 (talk) 11:43, 21 September 2015 (UTC)

I know the stats for my language. But I need them for the English language in order to prove to a site a situation I discovered is harmful. 2A02:8420:508D:CC00:56E6:FCFF:FEDB:2BBA (talk) 18:19, 21 September 2015 (UTC)

Are you asking what percentage of viewers of a certain page are likely to be using screen readers? If so, this page has some links and discussion [6]. You can also just look at distribution of blind people. In the USA [7], I think it's safe to assume that most blind adults use the web, but that might be less true in other places. There also might be some useful info here at WebAIM [8] SemanticMantis (talk) 18:58, 21 September 2015 (UTC)

Not exactly, I found an English only site which don’t filter protocols on the cite="" attribute but is doing it for other ones like href="" data="" src="". They refuse to change the current behavior by claiming the percentage of blind users that would be affected by the javascript: protocol on the cite="" attribute is probably very small.

I found various screen readers vulnerable to that case, but I couldn’t found if there’re used by a lot of users. (and to be honest, there’s is a bounty to win if I prove such a situation is harmful for blind users)

That’s why I need screen reader shares, the same way browser shares exists. 2A02:8420:508D:CC00:56E6:FCFF:FEDB:2BBA (talk) 23:12, 21 September 2015 (UTC)

I'm not visually impaired, or that familiar with accessibility issues, but my impression is that JAWS (screen reader) is the most popular screen reader. This is supported by our article, with a source [9], although their percentage is now well below 50%.

It seems from that source that JAWS, ZoomText, Window-Eyes, NonVisual Desktop Access, VoiceOver are what would need to be considered, at a minimum. This doesn't tell you much about versions of these software of course. Also the source mentions some further complications, like the fact some of the software also functions as a magnifier and that may be what some respondents were using and not the screen reader portion. (Also it wasn't just looking at people affected by blindness, although most did have some soft of visual impairment. Then again, I don't quite understand why the website you're referring to would only care about people using screen readers who are blind.)

The source, a survey by WebAIM, doesn't seem to be exclusively referring to English usage statistics, but considering their are based in the US with an English website, and the survey was I think in English, and a big percentage of their respondents came from the US, follow by Europe (including UK), then Australia and Oceania, it seems likely English users were a big percentage of users surveyed. Although interestingly, 25.6% did use more than on language.

Being a survey, and from the sound of it not one that even attempts to be random, it does run the risks such surveys normally do, still it's probably better than nothing. Also coming up with a good alternative is probably difficult, since screen readers are generally not exposed in the user agent or elsewhere from the sound of it [10].

However are you sure the website in question doesn't have their own data? If it's a competently run major website, it may have. For various reasons, website audience will often vary, and while it's possible the website design itself is one of the causes, I think in the end many website designers will care much more about their actual audience than the general audience. (Browser shares, which are normally derived from user agents are I think often handled that way.)

If they do have their own data, and it suggests for example that VoiceOver is not particularly significant to them, considering the somewhat low usage share in the WebAIM survey, it unfortunately may be difficult to convince them it's something to worry about.

I'll also ask User:Graham87 who uses a screen reader and is often a helpful source of information for accessibility related issues such as this, if they can offer any more help.

Nil Einne (talk) 14:38, 22 September 2015 (UTC)

I can't add very much to what Nil Einne and others said ... I was going to mention WebAIM, but you guys beat me to it! Regarding Windows, I get the impression that NVDA is more popular among more technically inclined users and users from non-English-speaking countries ... but its popularity is increasing across the board as more features are added to it, simply because of its status as free software compared to JAWS which costs about 1,100 US dollars. Graham87 14:51, 22 September 2015 (UTC)

Ok, looks like most of them use Internet Explorer. But for blind people who use other web browsers, what are the shares since those firsts ones here require Trident ?

I’m Ok to reveal the site name and more details. However, as this is an unpatched flow, this deserve private discussion. My guess is they added that attribute considering web browsers don’t use it, thus forgetting about visually impaired.

I also wonder on how to load the cite attribute with JAWS (screen reader), but I couldn’t find it. 2A02:8420:508D:CC00:56E6:FCFF:FEDB:2BBA (talk) 19:35, 22 September 2015 (UTC)

I'm not sure what I can say beyond the survey results, except they corroborate with my experience in this area. I had never heard of the protocol attribute before reading this thread. Graham87 02:01, 23 September 2015 (UTC)

No it’s the cite attribute which is often used with the blockquote ʜᴛᴍʟ element. 2A02:8420:508D:CC00:56E6:FCFF:FEDB:2BBA (talk) 09:30, 23 September 2015 (UTC)

Aha, I understand you now. I'd never heard of that one either, but I can imagine how it could be problematic. Graham87 13:56, 24 September 2015 (UTC)

How could VW and Audi software cheat the US regulations?

According to [11] "Diesel cars from Volkswagen and Audi cheated on clean air rules by including software that made the cars' emissions look cleaner than they actually were."

How can the VW and Audi software detect the car is being tested? As a first thought, I imagined that they analyzed the emissions coming out of the exhaust pipe, and do not need to connect to the car board computer or look at the dashboard. At least, that's how I expect a technical inspection to work. Relying on the cars' own sensors or software is tricky, even without fraud. You would not discover software or sensors malfunctioning this way. --Scicurious (talk) 15:38, 21 September 2015 (UTC)

A comment [12] by 1995droptop claims "EPA testing rules do not allow for anything to be plugged into the OBD port during testing." Another comment by BahamaTodd says "The car was able to detect humidity, steering angle, vehicle speed, and duration of operation, to determine that it was undergoing an EPA emissions test." (Also mentioned is how the EPA generally uses fairly well controlled enviroments, I presume for consistency and fairness.) A search based on that finds other sources of varying quality like [13] [14] [15] which say something similar, and also go in to detail on what they did in the testing mode and why they may have chosen to change the settings in normal driving mode. One of those links to the EPA which calls it a "defeat device" [16] which doesn't go in to details on precisely how it's believed to have detected testing, nor does the Notice of Violation [17]. However, although not the best sources, I'm inclined to trust that the earlier ones probably right in how it worked. Nil Einne (talk) 18:18, 21 September 2015 (UTC)

(Full disclosure: I designed some of the equipment used to conduct the EPA tests in question.) Emission tests are normally done on a dynomometer using the FTP-75 test schedule.

All VW had to do was to program the car to go into EPA test mode when the computer saw that the vehicle was going through the FTP-75 driving cycle combined with none of the normal steering corrections that happen as a human stays in his lane on the highway.

It's a well-known problem in the industry, and we have detection measures which I am not at liberty to reveal. The interesting question is how VW managed to not trip those detection measures (which no doubt have been updated several times since I was working with them). --Guy Macon (talk) 04:37, 22 September 2015 (UTC)

From our article Volkswagen emissions violations including its talk page Talk:Volkswagen emissions violations, and other sources like [18] and stuff I've heard on the news, it sounds like the cheating was uncovered because the International Council on Clean Transportation funded real world testing and found strong discrepancies between the lab tests and real world tests for some manufacturers including Volkswagen. Although as Guy Macon said the issue of possible cheating was I think fairly well known, and possibly observed by others conducted real world testing (like Emissions Analytics), the study caused enough concern for the EPA and possibly other US agencies (and I think EU ones too) to further investigate including eventual threats to withhold certification which lead to eventual admission; if some of what I've read is right, the ICCT wasn't actually so much trying to prove manufacturers were cheating on the US standards, but because they believed they were significantly better than the EU ones and wanted to show this but then uncovered the discrepancy. The greater difficulty of fair real world tests is I presume one reason why they weren't implemented yet, but it seems the EU and possibly South Korea and China was already strongly considering making them compulsory [19] [20] before the cheating had been confirmed (although possibly after the ICCT results). Nil Einne (talk) 07:31, 23 September 2015 (UTC)

How are Arabic glyphs actually rendered ?

Let's consider, for example, two letters: Arabic Jeem and the Pashto letter Dze. In Unicode the first has one its principal codepoint 062C, as well as four additional codepoints for its shapes (isolated, final, initial, medial) FE9D, FE9E, FE9F, FEA0. When you type the word jīm itself (جيم) the first glyph is supposedly not 062C but FE9F (the initial shape) this is why it has such a shape (ﺟ) and not (ﺝ).

The Pashto letter Dze (or Dzeem) in turn has only one Unicode codepoint 0681 and no codepoints for the shapes. But nevertheless the word dzīm is ځيم not ځ يم (I added a space between the letters to illustrate). How does it happen?

Bellow is the table. The first row is Jeem. It has four independent glyphs for its shapes. The second row is Dzeem. Its shapes are got with tatwil.

Final	Medial	Initial	Isolated	Character
ﺞ	ﺠ	ﺟ	ﺝ	ج
ـځ	ـځـ	ځـ	ځ	ځ

--Lüboslóv Yęzýkin (talk) 18:50, 21 September 2015 (UTC)

You’ll be interested in computer font kerning. It also allows to adjusts letters so they override. 2A02:8420:508D:CC00:56E6:FCFF:FEDB:2BBA (talk) 23:31, 21 September 2015 (UTC)

In Serbian, the italic shapes of certain letters differ from those in Russian. This is not encoded, the info has to come from somewhere else (such as the document's metadata - for example in wiki markup, the {{lang}} tag.) Similarly, in Greek, an algorithm to automatically put text into lowercase knows which form of the sigma to substitute (σ or ς) even though all it has is Σ (in other words, the relationship is one-to-many (non-bijective) and the algorithm has to guess based on context (such as whether the next character is a letter or punctuation.) The point is, Unicode text rendering engines are that smart Asmrulz (talk) 08:48, 22 September 2015 (UTC)

I appreciate your effort, but it does not explain the question. Two Greek sigmas has two different Unicode points, so it is not too difficult to create an algorithm. While a great deal of additional Arabic letter do not. You cannot simply say to a program "if a condition is such, then get this one code point/glyph and substitute with another one", as there is no "another one". I wanted to know how it miraculously happened that the letter Dzeem (remember it's just one of several dozens such letters) lost its tail in the middle and beginning and grew a little connector (conjunction?) at the end.--Lüboslóv Yęzýkin (talk) 15:03, 22 September 2015 (UTC)

Kerning table in the font file ? 2A02:8420:508D:CC00:56E6:FCFF:FEDB:2BBA (talk) 19:53, 22 September 2015 (UTC)

Kerning just adjusts the glyph's position. Ligatures are replacement glyhps. I think the font will have ligature rules embedded into it to show replacement glyphs in certain situations.

The Unicode website has a FAQ page about Ligatures, Digraphs, Presentation Forms vs. Plain Text. This page has many answers along the lines of "The existing ligatures exist basically for compatibility and round-tripping with non-Unicode character sets. Their use is discouraged. No more will be encoded in any circumstances." In particular, it looks like the term "presentation form" is a more precise term for Arabic. Here are some excerpts from that section:

• "Presentation forms are ligatures or glyph variants that are normally not encoded but are forms that show up during presentation of text, normally selected automatically by the layout software. A typical example are the positional forms for Arabic letters. These don't need to be encoded, because the layout software determines the correct form from context. For historical reasons, a substantial number of presentation forms was encoded in Unicode as compatibility characters, because legacy software or data included them."
• "Can one use the presentation forms in a data file? A: It is not recommended because it does not guarantee data integrity and interoperability. In the particular case of Arabic, data files should include only the characters in the Arabic block, U+0600 to U+06FF."

--Bavi H (talk) 03:37, 23 September 2015 (UTC)

Here is a page that has detailed information: Understanding characters, keystrokes, codepoints and glyphs. In particular, section 3.3 From codepoints to glyphs seems relevant. This section describes a hypothetical English "handwriting" font, that could display letters in different ways depending on the context.

• "As I work through all the details, I might actually decide that the only way to really get the word "picture" to display the way I want is to create it as a single, complex glyph for the entire word. (This may seem unusual, but such things are possible in fonts, and some fonts have even done things like this.) So, I have a single glyph for "picture", but this is stored in data as a sequence of seven characters. What I need, then, is for some process to intervene between the stored data and the glyphs that will recognise this particular sequence of characters and select the single, combined glyph, rather than seven separate glyphs. This is precisely the kind of processing that happens in modern systems that are designed to support complex scripts."

--Bavi H (talk) 04:00, 23 September 2015 (UTC)

After some research I found the more specific answers. Arabic letters are represented with the help of two principal things:

• The Glyph Substitution table (GSUB) in the font itself [21]. It can be seen (and edited) in programs like FontForge[22]. If the table is absent in the font (and I have such old fonts, without the GSUB but with the representation forms-B block), the representation forms will not appear.
• Uniscribe or similar services. And I was somewhat wrong: the presentation form blocks A and B were introduced into Unicode only for compatibility, their usage are strongly discouraged now[23], this is probably why many fonts lack the blocks altogether. The scenario I described above (the code point substitution) was used only in some older software (though I do not know what exactly).

Thanks to Bavi H for a hint in what direction I had to research. --Lüboslóv Yęzýkin (talk) 20:27, 24 September 2015 (UTC)

September 22

Spam e-mails

I receive quite a number of e-mails, ostensibly from people I know, usually sent to a number of addressees, with the heading "from: " followed by the person's name. The content is always just a web address (which I never click on) and the person's name. Should I be concerned about this, and should I notifying the supposed sender? Sorry if this is a well-known phenomenon that I ought to have known about! --rossb (talk) 08:17, 22 September 2015 (UTC)

There are many scenarios for this:

• Worst case... You have a virus/malware on your computer that is scanning your emails and sending you spam from people with whom you currently exchange emails.
• likely... Someone you know has a virus/malware on his/her computer that is sending out spam using all the email address in his/her email program.
• Most likely... A spambot is sending you tons of email using an email list harvested from some site you've given your email address to. Others who know also gave their email addresses to it. So, you sometimes see names you know.

Realization... The number of computers that have malware on them that spend all day and night sending out spam is MUCH larger that most people think. Simply getting everyone to turn off their computer when they aren't using it will prove this point because it will greatly reduce the processing power the spammers have. However, humans are highly addicted to screens and they don't like to have screens turned off. As a species, humans have become dependent on having screens scattered throughout the home, installed in the dash of cars, hanging randomly throughout stores and restaurants, on nearly every desk at work, and now they must carry a live screen with them everywhere they go and stare blankly at it while driving - only taking attention away from the mobile screen periodically to look at the other little screen on the dash... Seriously, I wasn't expecting this to turn into a completely off-topic rant. 209.149.113.66 (talk) 13:10, 22 September 2015 (UTC)

DVD problems, specifications

Hi, I have a brand-new, double-sided DVD. Both sides look pristine. The first side plays fine. When I attempt to play the second side on my Xbox 360, it the device hangs on "reading", with no error messages. Similar behavior when attempting to play second side on two other (Mac) computers. These devices have never had problems playing other DVDs. I have no DVD-player-only device to try the disk on. Questions:

1. Is this any sort of generally known issue with two-sided DVDs? My searches just lead to one-off posts, discussions of cleaning, defects, etc.
2. Is it possible that the Xbox is somehow failing to comply with specifications for reading a second-side format? When the first side plays to the end a "turn over disc to continue" message appears, and I wonder if maybe a conventional DVD player is supposed to hold some data/metadata in a buffer to properly load the second side.
3. I realize factory defect is a simple and parsimonious possibility but a)I've never had that happen b) the disc has no obvious scratches, dust, etc on it. c) when I have had flaws in the media, usually the player will throw some sort of error message, not just attempt to read, apparently forever. Is there any reasonable explanation here that isn't a flaw in the optical media?

Thanks, SemanticMantis (talk) 15:50, 22 September 2015 (UTC)

I suspect a factory defect, but not the type of damage you mentioned. Rather, I suspect that the index isn't configured correctly, so it tries to read data where there is none (perhaps they just repeated the side one index instead of creating a proper index for side 2). If so, most likely the whole batch was bad. Them not catching it implies poor quality control, making me suspect a counterfeit. You might return it to wherever you bought it and say you suspect it's counterfeit. (They may not have known, as it could be inserted at any point in the supplier chain.) StuRat (talk) 16:23, 22 September 2015 (UTC)

I'd advice not to buy a double sided CD, it might save space but product reliability is '???' e.g., it might create problem during writing on the disk, might matter if it heats up, and so on. -- Space Ghost (talk) 19:08, 23 September 2015 (UTC)

The OP appears to be referring to pressed DVD, so writing to the disk is irrelevant. Also, double sided CDs which you referred to, and double DVDs are very different things. Double sided CDs are inherently non standard, as sort of hinted by the DualDisc because either the thickness of each side is too thin, or the overall CD is too thick; as the reflective layer is normally on the top side of the disc. However as mentioned by our DVD and sort of hinted by the earlier article, double sided DVDs have been part of the standards from very early on. Even a single sided DVD is still made up of two discs bonded together [24]; the reflective layer is in the middle.

To answer the OP's question. Each side is independent, and the Xbox 360 or any device doesn't have to know or care, what's on the other side. However it does appear that the way double sided dual layer DVDs are produced, it's a little more complicated even if you're always always bonding two discs together [25] [26].

Nil Einne (talk) 21:52, 23 September 2015 (UTC)

[[File:|25px|link=]] -- Space Ghost (talk) 18:15, 24 September 2015 (UTC)

area code 326 - used or not?

Checking the Missed Calls on my phone, I found one from 1-326-800-1698. The caller ID was "3268001698". Out of curiosity, I looked up the area code at https://en.wikipedia.org/wiki/List_of_North_American_Numbering_Plan_area_codes#300.E2.80.93399 where it says "326: not used". I dialled the number and got the message, "We're sorry, your call cannot be completed as dialled. Please check the number and call again. This is a recording." Can anyone explain this? 99.225.220.233 (talk) 18:43, 22 September 2015 (UTC)

Could be a case of Caller_ID_spoofing. SemanticMantis (talk) 19:27, 22 September 2015 (UTC)

It is an air duct cleaning scam out of India with a spoofed caller-ID. Give them your credit card number and they will give you an appointment time so you can wait for the technicians to arrive. And if they don't show, just call 1-326-800-1698 to complain... --Guy Macon (talk) 21:08, 22 September 2015 (UTC)

I just wanted to add the North American Numbering Plan Administration website (www.nanpa.com) has freely available data and searches, in case you ever want to confirm directly from the source. According to their area code search, area code 326 is not assigned. --Bavi H (talk) 01:59, 23 September 2015 (UTC)

Can I swap toner from HP to Epson cartridge?

I have an Epson c2900 laserjet printer that is low on black toner. I also have a HP laserjet 92298A black toner cartridge laying around.

Can I open them up and swap the toner into the Epson cartridge? Is HP and Epson black toner fundamentally different somehow?

Thanks 66.194.234.102 (talk) 18:54, 22 September 2015 (UTC)

Toner refill has a lot of relevant info here. I know we're not really supposed to give personal opinions but I have dealt with broken laser toner cartridges on a few occasions and I think this sounds like a terrible idea, mostly for the reasons already listed in the linked article. Vespine (talk) 00:19, 23 September 2015 (UTC)

(more personal experience) I've ruined a refillable cartridge by filling it with the wrong toner. On the other hand, I've successfully refilled a cartridge using toner from the same manufacturer but emptied out of an obsolete cartridge designed for a different model. I haven't found an easy way to tell whether toner is compatible or not, other than "try it and see". Dbfirs 20:17, 23 September 2015 (UTC)

September 23

What does this thing do?

I have this thing in my house: http://static2.shop.indiatimes.com/images/products/additional/original/B947843_View_1/computers/routers-access-points/netgear-8-port-10-100-mbps-fast-ethernet-switch-fs608.jpg Is it used to plug multiple ethernet cables into one internet source so you can provide wired internet to multiple devices? Where would the "master" cable go, 1? I'd have to buy a power cable to actually activate it. 2605:6000:EA01:7E00:5CB3:9484:FCC0:A798 (talk) 05:15, 23 September 2015 (UTC)

It is a network switch. The master cable would go to another switch. You use this to network a bunch of computers together. To get those computers on the internet you would also need a modem and router. Thing is, what most call a modem these days is actually a modem, router AND a switch all in one. But what you have there is not one of those (does your modem/router have more than one Ethernet port on the back? If yes then it is also a switch). If you ALREADY have a modem/router then chances are you also already have a switch. If you have MORE devices than your existing "router" has sockets then you use exactly this device to plug more devices into it. That's exactly what I do. Vespine (talk) 05:50, 23 September 2015 (UTC)

The other side has exactly eight ethernet ports, labeled 1-8. My apartment has an ethernet cable sticking out of the wall from where I get my internet. With enough ethernet cables, is there a way to use this device so that me and my roommate can both use wired internet at the same time? 2605:6000:EA01:7E00:5CB3:9484:FCC0:A798 (talk) 06:13, 23 September 2015 (UTC)

I'm guessing this isn't really your "house" but a dorm? or something? Most houses don't just have a Ethernet cable sticking out of the wall with internet coming out of it :) . when you plug that cable in to your computer does the internet just work? You don't have to "log into it" or something? If the answer to that question is yes, then most likely the other end of that cable is just plugged into a router(or switch which is plugged into a router), in which case: yes, just plug that switch into the Ethernet cable that comes out of the wall and then use other Ethernet cables to plug your computers into the switch. Vespine (talk) 06:27, 23 September 2015 (UTC)

Yeah, it's an apartment, not a house, I misspoke in the OP. I'll purchase a power cable off the internet so I can use this thing, that'd be great if roommate and I could use the internet at he same time. 2605:6000:EA01:7E00:DC32:1845:CCB4:D0C0 (talk) 14:08, 23 September 2015 (UTC)

I need help :( I can't figure out how to buy the right power supply for this device. The plug port's really tiny, like 4 mm in diameter. There's a label that says 7.5VDC. 0.8A and an icon that looks like (-)--(C)--(+). Im afraid to buy a cable off Amazon because it's 13 bucks and I don't want to be wrong. Can anyone link me to what would for sure be the right cable for this device? 2605:6000:EA01:7E00:6950:3903:9776:7A7B (talk) 00:48, 24 September 2015 (UTC)

Can't you return it if it's the wrong thing? If you're that concerned, just buy a new switch. If you're in the U.S., NewEgg often has the best prices on computer hardware. Here are their network switches. --71.119.131.184 (talk) 04:41, 24 September 2015 (UTC)

this will do the job just fine. Vespine (talk)

You can always try including the model number of the device in your search. I think the model number of that switch is Netgear FS608v2. On a site like eBay you will almost certainly be able to find a power supply whose description says it works with that model. Not that that's any guarantee, but it's better than nothing. —Noiratsi (talk) 16:09, 24 September 2015 (UTC)

As a side note, the model number will also let you find the user manual online, which should help with figuring out what to plug where. —Noiratsi (talk) 16:11, 24 September 2015 (UTC)

Is there a way to find out where this picture was first posted?

I found a fake account: www.kiwi.qa/SaNdRInhA125/media I know that this account is fake, because this pictures can be found 100 times on 100 different sites. Is there a way to find out where this pictures were first posted? (for example of which Instagram/twitter/facebook/flickr/etc profile they have been stolen) ? --Hijodetenerife (talk) 05:35, 23 September 2015 (UTC)

Yes, go to Google Images and click on the little camera in the search field. You'll need to perform a reverse image search. You'll find the same image in 100 different sites, according to your claim. Now, you'll click on "Search tools" + "Custom range." Set the time range and go back as much as possible. That will lead you to the original uploader.--Jubilujj 2015 (talk) 06:59, 23 September 2015 (UTC)

Actually, very often that won't lead to the original poster. Whether using Google Images or TinEye, there are plenty of sites not indexed or not completely index. And for many sites like Facebook, even if Google wanted to they couldn't since they can't easily access non public stuff. Also, Google mostly indexes the web, some things like Snapchat use the internet but not the web. (If you argue that the person who sent it via Snapchat isn't the first poster, then what about sending via Google Groups and similar such chatting apps, which puts the image on Picasa or somewhere similar?) And even when content is indexed, reverse images search don't always work so well if the content has been significantly modified such as extensively cropped. Plus people can and do delete content after posting and if it's been long enough there may be limited signs of the old content, and even those which do exist are easy to miss and won't be found via a reverse image search. Reverse image searches can provide some clues about how the image has moved around, and sometimes may uncover the first poster, but shouldn't be confused with magic. Nil Einne (talk) 07:43, 23 September 2015 (UTC)

Yes, you are right, image search is kind of primitive. I should have said "could lead" to the original poster, not "will lead". However, the OP could try to consider other clues. The pictures have to be of someone somewhere, and possibly the person on the picture posted it too, or allowed for it. It requires some sweat to dig the original poster, but it maybe could be found. --Jubilujj 2015 (talk) 10:53, 23 September 2015 (UTC)

Virtualization: Windows on Linux, or Linux on Windows?

I want to work simultaneously with both Windows 8 and Linux (any Debian-based distributions. I got a laptop with Windows 8 already installed, and I want to keep it, since it works well with the touchscreen and other hybrid (laptop + tablet) features.

What do I have to do to have Linux and run both at the same time?

I want to move between OSs as I move from one tab to the next in the browser. I also need the Linux version to be connected to the Internet, and, to be able to install software on it (with apt-get). And last, both OS should be able to read and write files in one driver.

Is that too much to ask?--Jubilujj 2015 (talk) 08:49, 23 September 2015 (UTC)

Install VirtualBox on Windows. Download an Xubuntu .iso file and create a new VirtualBox VM with that mounted on the optical media. In VirtualBox, set the VM's ethernet adapter to "bridged adapter" and as a Broadcom gigabit adapter. Boot into the VM and install Xubuntu. You can use VirtualBox's "shared folders" setting to share folders between windows and linux, or use SMB to share folders from one to the other over the network. In VirtualBox's UserInterface tab, set full-screen/seamless mode, which makes the Xubuntu desktop disappear - so only its menubar and the individual Xubuntu application windows appear on the screen (as if they were ordinary Windows application windows). -- Finlay McWalterᚠTalk 09:19, 23 September 2015 (UTC)

Oh, and once the Xubuntu is installed, choose the option (in the VM window somewhere) to "install guest additions". This inserts a virtual DVD into the VM's virtual drive, which contains kernel extensions which allow for things (networking, video) to work faster than they would with the default drivers the kernel has. Run the installer program there, and restart the VM. -- Finlay McWalterᚠTalk 09:28, 23 September 2015 (UTC)

OK, that looks doable. Also found [27] with some extra details. I will definitely implement this.

One last question, can I block Windows 8.1 from accessing the Internet, but still allow my Xubuntu on VM to access it? --Jubilujj 2015 (talk) 10:48, 23 September 2015 (UTC)

If you want a solution which can guarantee no malware or malicious privileged user of the Windows OS can access it then I would say no, the Windows OS is the host OS and so ultimately has control over the hardware resources including network adapters so anything you can do to let the guess OS access the network could be repeated on the host OS.

If you just want to ensure the Windows 8.1 OS doesn't normally have internet access, sure. Presuming you use DHCP to assign IPs and gateways to the ethernet adapters, just turn off DHCP for both IPv4 and IPv6 on the Windows 8.1 OS and set up bridged networking for the guest and turn on DHCP. If you want to make it less likely the host will accidently receive network access and you have control over the DHCP server and it has the option, turn on MAC filtering and don't allow the host network adapter's default MAC address to receive an IP. Alternatively, set it up so it's always assigned a specific IP, then firewall that IP so it can't send and receive anything over the internet. The later may also be the simplest solution if you want to disable internet access, but still allow access to any LAN you may have. (If you just want to allow networking between the guest and host, you could set up a seperate host only networking adapter.)

Nil Einne (talk) 21:24, 23 September 2015 (UTC)

data survivalism?

what is the academic discipline that works on making data survive and pass onto newer hardwares? when the servers on the internet start to die, most of the internet going into oblivion is worth much nightmares.

Scientific data archiving, Digital preservation? --Jubilujj 2015 (talk) 12:47, 23 September 2015 (UTC)

Some of this can also come under the heading of data curation and digital archiving. More generally, Library science and information science deal with this sort of thing, but the names of subfields are often a bit of a moving target. SemanticMantis (talk) 14:11, 23 September 2015 (UTC)

anti-DNS

in all the years of problems related to the use of DNS, why has no group popped up which opposes DNS use and advocates a strict "browse using ip address" policy? — Preceding unsigned comment added by 2A03:2880:3010:BFF9:FACE:B00C:0:1 (talk) 13:03, 23 September 2015 (UTC)

There are such groups. There are also groups that strictly implement their own DNS. There are also people who manage their own hosts file and don't use DNS. 209.149.113.66 (talk) 13:29, 23 September 2015 (UTC)

Because it would be completely impractical. What problems, exactly, exist with DNS that would not exist if people typed in IP addresses? --71.119.131.184 (talk) 14:49, 23 September 2015 (UTC)

I think you underestimate how useful DNS is. I'm on a laptop, my IP address can change several times a day as I travel from office to home or to a wifi hotspot. I can visit Google no matter where I am on the planet and get a local site that's fast and responsive. My internet banking site can go down and my bank can bring up a backup site without me even noticing. None of that would be possible if I was just using IP addresses. Vespine (talk) 04:21, 24 September 2015 (UTC)

Just to clarify, I'm not saying it would be impossible, it would be possible, but it would be harder, or you would have to use "work arounds" that would basically do the same thing that DNS does now. Vespine (talk) 05:11, 24 September 2015 (UTC)

DNS is useful, but weak. Suppose you go into my coffee shop to drink overpriced coffee and do your banking. You don't know that I'm running my own internal DNS. You go to mycoolbank.com and my DNS gives you the wrong IP address. You end up hitting one of my servers. My server sends you a fake version of the bank's website. You are smart. You switch it to HTTPS to be secure. That still hits my server because DNS is pointing you there. But, since you want to be secure, my server sends you a Thawte certificate to prove that it is the real banking website. Of course, it is a fake certificate. You can figure that out quickly by asking thawte.com to verify it. But, you are using my DNS. So, I point you to my fake version of Thawte which replies that the fake certificate is perfectly valid. You see that you are safely secure and happily type in your login name and password into the fake website. Then, you get a "down for maintenance - try again later" message from my server. So, you check your credit card accounts, work email, etc... all using my DNS and servers. But, we can solve this problem. All we have to do is hard-code trusted DNS servers into our computers. Remember, you are on MY network. You send a DNS to 4.2.2.2 because that is a trusted DNS. I simply have my network set up so one of my DNS servers is 4.2.2.2. So, no matter what you do, I can trap your DNS and completely fake everything you try to do. For that matter - I could go so far as to redirect traffic using IP instead of DNS. So, that is why this problem is allowed to exist. Getting rid of DNS doesn't solve the problem. It just morphs it a tad. 209.149.113.66 (talk) 12:57, 25 September 2015 (UTC)

Javascript elemental definitions

Hello, a question about fundamental JS. is the .location in the following code an object or a property?... If it's an object (just document) how come it has a (dot) property accessor? I ask because my teacher defined it as an object, but it does have a property accessor... Please help me understand, thank you,

<body onload="go2;">

<script>

function go2() {document.location ="http://www.google.com";}

</script>

</body>

Thanks, Ben-Yeudith (talk) 14:47, 23 September 2015 (UTC)

It's special. It is a "read-only property" - buuuut that also says "Though Document.location is a read-only Location object, you can also assign a DOMString to it". Which is the opposite of read-only, right? Writing to document.location effectively calls a function. If someone wanted to build their own thing that worked like that, as far as I know, one can't do that in pure Javascript (through ES5.1). ES6 adds Proxy support. But the "document" object is a magic thing generated by the browser - it's not necessarily actually a regular JavaScript object at all (it just appears to work like one), and I suspect that this behaviour (in current browsers at least) is special hardwired code. -- Finlay McWalterᚠTalk 15:16, 23 September 2015 (UTC)

added underscored parts above for clarity. -- Finlay McWalterᚠTalk 19:45, 23 September 2015 (UTC)

What are the current impediments in creating text to speech voices?

OP wished for lots of text to speech voices created and released on the internet by TTS hobbyists. — Preceding unsigned comment added by 2A03:2880:3010:BFFB:FACE:B00C:0:1 (talk) 17:29, 23 September 2015 (UTC)

Well, it's a lot of work for a person to record all the sounds needed to make speech, all at the same volume, tone, speed, etc. Then the audio clips/samples need to be stitched together and tested, not unlike "looping" (recording the audio soundtrack for a movie). So, somebody has to pay for all that work. StuRat (talk) 19:36, 23 September 2015 (UTC)

Some text-to-speech methods use recordings of human voices, others do not, e.g. Speech_synthesis#Formant_synthesis. For example, many screen readers do not use human-voiced samples. Our article also has a whole section on Speech_synthesis#Challenges, that addresses OP's question. SemanticMantis (talk) 22:25, 23 September 2015 (UTC)

bash question

Hello. In a particular context, I pipe every single command through nl and then through tail. So, for example, I will type "ls -lSr | nl | tail" and look at it, do some stuff, then maybe "cat * |egrep 'foo'|sort -n |nl|tail". I'm on a slow tty and if I forget the tail it's a pain in the neck because I have gazillions of files and the command takes forever to finish echoing (and I am only interested in the last few lines anyway). How can I instruct bash to pass all output that would go to stdout through nl and tail? Robinh (talk) 21:22, 23 September 2015 (UTC)

You can type bash|nl|tail. And then enter the commands. When you exit, the last 10 lines will output. Graeme Bartlett (talk) 21:39, 23 September 2015 (UTC)

Thanks for this, I didn't know you could do that. It works! But this solution doesn't have the interactiveness I want. I want to be able to type ls -l, look at the (last few lines of) the output, fiddle with some settings, type cat *|egrep 'baz' (where 'baz' will depend on the output of ls), fiddle again, and so on. And with bash|nl|tail I can't do that. Any advice? Robinh (talk) 21:47, 23 September 2015 (UTC)

Another more interactive way is to do this:

while read j ; do exec $j|nl|tail ; done

Then type your commands one by one. ^d will exit. Graeme Bartlett (talk) 22:07, 23 September 2015 (UTC)

Hmm, there might be a more efficient way to do this particular task. You might want to look at using something like Midnight Commander or dired to work with files via terminal. Also, if you're trying to work remotely over a slow connection, it might be easier to just use rsync to download the files you're working on to your local system. Then you can work locally and use rsync to upload any changes. I'm assuming by "slow tty" you mean a slow network connection, because I think it unlikely you're working on an actual physical terminal hooked up to a mainframe or minicomputer, but I could be wrong! --71.119.131.184 (talk) 22:45, 23 September 2015 (UTC)

(OP) thanks guys. I never thought to do the while read j thing. This works for "ls -ltr" but doesn't quite work for "cat <allfiles> | egrep 'foo' " Robinh (talk) 04:16, 24 September 2015 (UTC)

And yes, by "slow tty" I did mean that I have a slow network connection. The other issue is that a massive output stops me from scrolling up to see previous command output. best wishes, Robinh (talk) 04:18, 24 September 2015 (UTC)

Unfortunately the exec only takes a single command and parameters, not a command string. Perhaps you could write the $j to a temp file and then execute it. I also failed to get this to work by direct substitution. Graeme Bartlett (talk) 11:58, 25 September 2015 (UTC)

• Here is a better version:

while read j ; do eval "($j|nl|tail)" ; done

• This time you can insert pipelines as input. Graeme Bartlett (talk) 12:32, 25 September 2015 (UTC)

One fix for your problem is to use GNU Screen. The problem you have is that it takes too long for the display to update over the network. You can press Ctrl-D to detach a screen session. Then, all updates are local to the machine and happen very quickly. When you reattach the screen, you will only see the final page of text. I use screen religiously because I have a network that disconnects whenever it feels like it. With screen, my session remains active. I can login to the server when network is back and reattach the session that I was disconnected from. 209.149.113.66 (talk) 13:11, 25 September 2015 (UTC)

September 24

Why there are no android app with all 105 keys of IBM keyboard?

really feeling the lack of pageup, pagedown and delete. — Preceding unsigned comment added by 2A03:2880:3010:BFFA:FACE:B00C:0:1 (talk) 04:05, 24 September 2015 (UTC)

Have you tried Hacker's Keyboard? (link to Google Play Store). —Noiratsi (talk) 16:17, 24 September 2015 (UTC)

COPY VCD TO PEN DRIVE

My friend has an old video CD and he wants to copy the video to a pen drive to preserve the video. It has the following folders and files. CDI(CDI_IMAG, CDI_TEXT.FNT, CDI_VCD.APP, CDI_VCD.CFG), EXT(LOT_X.VCD, PSD_X.VCD, SCANDATA.DAT), MPEGAV(AVSEQ01.DAT), SEGMENT, VCD(ENTRIES.VCD, INFO.VCD, LOT.VCD, PSD.VCD). How can he copy the video to pen drive? Thank you.175.157.41.176 (talk) 05:12, 24 September 2015 (UTC)

From memory, and it has been a while, there should be one or two files that are clearly larger than all the rest (possibly the DAT file?), that's all a media player like VLC needs to play the video. Just put that (those) file(s) on the pen drive and try to play it, if it works you are done. Vespine (talk) 06:09, 24 September 2015 (UTC)

According to this, the video data is in AVSEQnn.DAT file(s). Ssscienccce (talk) 11:42, 24 September 2015 (UTC)

Also from memory, but yes, that's correct. The AVSEQ01.DAT is simply an MPG file, so you can even rename the extension to MPG to make it easier to classify if you'd like. 64.235.97.146 (talk) 15:52, 24 September 2015 (UTC)

Thank you all for the advice.175.157.12.52 (talk) 02:46, 25 September 2015 (UTC)

What is the most powerful lossless compression setting for video created upto now?

OP was tinkering with various compression settings, codecs, color depths so on, suddenly this thought. — Preceding unsigned comment added by 2A03:2880:3010:BFF8:FACE:B00C:0:1 (talk) 06:49, 24 September 2015 (UTC)

FFV or https://en.wikipedia.org/wiki/Huffyuv 217.158.236.14 (talk) 15:02, 24 September 2015 (UTC)

I said SETTING, NOT CODEC ONLY. that means encoder+color depth+audio sample rate+color scheme+additional tweaks. I want the whole setting. — Preceding unsigned comment added by 2A03:2880:3010:BFF5:FACE:B00C:0:1 (talk) 16:33, 24 September 2015 (UTC)

Well, if you change colour depth, or audio sample rate, or most of the rest, it's not lossless, is it? Reduced the colour depth -> lose colour information.--Phil Holmes (talk) 17:17, 24 September 2015 (UTC)

Replacement wireless card for old notebook?

So I think the wireless adapter is gone. Are these parts standardized or are they specific to individual models or makes. This is the part I'd like to try and replace...

https://www.google.co.uk/search?q=BCM94312MCG&es_sm=122&source=lnms&tbm=isch&sa=X&ved=0CAcQ_AUoAWoVChMIpf6nw9KPyAIVBS4aCh0pgAZn&biw=1344&bih=724 — Preceding unsigned comment added by 80.195.27.47 (talk) 12:17, 24 September 2015 (UTC)

Does it have a USB port? There are plenty of USB wifi cards that are barely bigger than the USB port, see here for example. RegistryKey^(RegEdit) 16:23, 24 September 2015 (UTC)

Can a user patch a security flaw in proprietary software?

Can a user patch a security flaw in proprietary software? Or, is his only alternative to wait until the software developer patches it? --Bickeyboard (talk) 23:16, 24 September 2015 (UTC)

Do you have access to the source code? Do you know how to fix it? A Quest For Knowledge (talk) 23:18, 24 September 2015 (UTC)

No, I am thinking about something like Windows XP. Can any company (that's not MS) offer updates on it? I suppose MS won't release an open-source version of it? Can an add-on be implemented to correct a malfunctioning closed-source proprietary software? --Bickeyboard (talk) 23:22, 24 September 2015 (UTC)

It is theoretically possible to modify a program in binary form; but in normal cases, this type of modification is prohibitively difficult.

However, some security problems can be resolved without modifying the flawed program: for example, a user can make a configuration change, isolate sensitive systems or data, and so on. Such corrective action could be provided as a service by an external vendor other than the original system software vendor. Nimur (talk) 23:54, 24 September 2015 (UTC)

Asking "Can a user patch a security flaw in proprietary software?" is like asking "Can a man climb Mount Everest?". The answer is "Technically yes but practically no!" 175.45.116.61 (talk) 00:04, 25 September 2015 (UTC)

Weird example since many men have climbed Everest. StuRat (talk) 04:39, 25 September 2015 (UTC)

This answer is simply wrong. Why would it be practically impossible to climb the everest? Just say that you don't believe that binary programs can be modified. --Scicurious (talk) 04:54, 25 September 2015 (UTC)

I presume the OP was thinking of averages. However intentionally or not, perhaps the OP's example does have some parallels. In particular, it's sometimes suggested that nowadays anyone can climb Everest if they have enough money [28] [29]. Similarly, if you're willing to pay enough, you can probably get someone to patch a security flaw in proprietary software without the source code.

However if the source code does exist, it may be more effective to pay whoever has the source code to either do it themselves or let someone else do it. Banks and some other major customers are doing or did do this with XP for example [30] [31] [32] [33]. ATMs for example are often still using XP, and while some XP Embedded support is until 2016 and some until 2019 [34] [35], not everyone is using it.

Where the OPs parallel may fail is that you generally aren't going to die from trying to patch your propietary software (whether mostly by your own efforts or someone you paid). Also, although there may be controversy over some people possibly treating Everest as an expensive tourist trip, as the earlier sources also say plenty of people do put in a lot of effort themselves when you can expect this won't be the case for a lot of proprietary software. Finally if you did want to pay money, you're always going to be paying someone else, you can pay Everest to help you climb it.

Nil Einne (talk) 07:12, 25 September 2015 (UTC)

September 25

Windows 10 - search inside files

I have a folder with my Word documents and I want to find all of them that contain a specified word. If I search the folder in Windows 10, it only shows files that have that word in the title. (I thought that Windows 7 and 8 would look in the files.) I have indexing on for that drive, if that matters. How can I easily search for files that have a specified word inside? Bubba73 ^{You talkin' to me?} 03:25, 25 September 2015 (UTC)

Earlier versions of Windows (XP ?) allowed you to explicitly specify where you wanted to search (the contents or the title). I think they dropped the option to search the contents of files at some point, or at least made it harder to find. Most likely this was due to the extreme amount of time it can take to search the contents of lots of files. StuRat (talk) 04:35, 25 September 2015 (UTC)

The ability to search within file contents was never dropped. In fact, it's been the default since Vista to always search within file contents for indexed files. (This can be annoying at times, although you can use search options like "name:" to avoid it.)

For non indexed files, searching with the file contents was never dropped either although the ways to access it have been a bit more varied. For starters, you have always been able to access it via the advanced search options, although the precise name may have varied and that sets the default. In Explorer versions with the ribbon, you can probably change the default option by clicking on the search ribbon and then "Advanced options". With some versions of Windows, you can also use "contents:" or "content:" to search within files (but I have heard this didn't work in certain versions like Windows 7 SP1) and in others, you may be offered the option after searching.

However content searches need to be understood. Under the indexing options, you can choose whether to index a file contents or properties only. Not all file types will have the contents indexed by default. Also, for binary files even if you turn on indexing, you may not have satisfactory results unless you have an IFilter for the file, Windows needs to know how to understand the file to properly index it.

On some, I think all versions of Windows since Vista (see Features new to Windows Vista#Windows Search), content searches for non indexed files will also work the same way. This includes file types which don't have their contents index not having their contents searched. (Nominally Microsoft could have used Ifilters in addition to a simple text search for either files which don't have their contents indexed at all, or for all files in addition to any ifilters that may be used, but I believe this wasn't done, or at least it isn't now.)

This means you can't search files whether binary or text which Windows hasn't been told to treat as text files for indexing. You will need to adjust your indexing file type options to search the contents of files (which will treat them as text normally) for those you want to search which Windows hasn't been set up to use an IFilter or treat as text. (To give an example, text subtitles like .srt and some .sub probably won't be treated as text by default. mkv and avi likewise.) Since you can't add wildcards, I think this means you have to add all extentions to treat them all as text. So if you want to do a GREP like search within all files even binary files for a text string, as was the case with Windows XP and 2k, I'm not sure if Windows Search is the best option.

As to where this leaves the OP, Office should provide IFilters so if the OP has Office installed, Word documents should be set up to be indexed with appropriate Ifilters. It may be worth checking the various document types, particularly the ones the OP is having problems with (.docx?) to make sure. If the OP doesn't have Office, then they may not have suitable Ifilters so this definitely should be checked. The latest IFilters from Microsoft publicly available appear to be the Office 2010 ones [36] since the 2013 ones disappeared [37]. The 2010 ones should however work fine with all files made with 2013 or even 2016. You can also look here [38] although from what they list I don't think it's been updated for a while.

Presuming Word documents are having their contents indexed with the appropriate ifilters and since the file locations are being indexed their contents should be searched, and there's no need to worry about searching in contents for non indexed files. One possibility is the index isn't complete yet, if there has been a major change recently the index may be being rebuilt and when this is happening, search results can be confusing. It may be worth searching with contents for non indexed files just to check although I'm not sure if this will help if the index is being rebuilt.

Nil Einne (talk) 06:39, 25 September 2015 (UTC)

Dependencies of Qubits

If $|z\rangle =|x\rangle \wedge |y\rangle$ (that is, $|z\rangle$ is the output of the "and" Quantum gate on the inputs $|x\rangle$ and $|y\rangle$) and we measure $|x\rangle$ and we get the result $|1\rangle$, and we measure $|y\rangle$ and we get $|1\rangle$ then necessarily a measurement on $|z\rangle$ yields $|1\rangle$ too? That is, do the measurements on $|x\rangle$ and on $|y\rangle$ affect the measurement on $|z\rangle$?

Similarly, if we measure $|z\rangle$ and we get $|1\rangle$, does this yield that a measurement on $|x\rangle$ and on $|y\rangle$ both give $|1\rangle$ ? 80.246.136.31 (talk) 09:33, 25 September 2015 (UTC)