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:''This is it, as far as C is concerned'', but see above. Your program will most likely crash. In simpler systems running on simpler hardware, such as DOS running in [[Real mode|real mode]], this was, however, a totally "legit" way to access memory at known addresses, for example in order to write to the video memory or to read the BIOS data area that contained various useful info about the computer (such as the number of floppy drives or [[RS-232|COM]] ports and their respective addresses.) [[Special:Contributions/78.50.124.31|78.50.124.31]] ([[User talk:78.50.124.31|talk]]) 20:38, 31 December 2017 (UTC)
:''This is it, as far as C is concerned'', but see above. Your program will most likely crash. In simpler systems running on simpler hardware, such as DOS running in [[Real mode|real mode]], this was, however, a totally "legit" way to access memory at known addresses, for example in order to write to the video memory or to read the BIOS data area that contained various useful info about the computer (such as the number of floppy drives or [[RS-232|COM]] ports and their respective addresses.) [[Special:Contributions/78.50.124.31|78.50.124.31]] ([[User talk:78.50.124.31|talk]]) 20:38, 31 December 2017 (UTC)
:<small><small>I take it your misconception about memory stems from the phrasing "can be thought of as an array... at location 0." This is a [[Lie-to-children|simplification]], but good for you thinking ahead, apparently you're the first participant of your course to do so [[Special:Contributions/78.50.124.31|78.50.124.31]] ([[User talk:78.50.124.31|talk]]) 20:59, 31 December 2017 (UTC)</small></small>
:<small><small>I take it your misconception about memory stems from the phrasing "can be thought of as an array... at location 0." This is a [[Lie-to-children|simplification]], but good for you thinking ahead, apparently you're the first participant of your course to do so [[Special:Contributions/78.50.124.31|78.50.124.31]] ([[User talk:78.50.124.31|talk]]) 20:59, 31 December 2017 (UTC)</small></small>

==== C programming β€” "{{mono|printf("%d\n",*(int*)0x7ffed73897d8)}}" worked and I'm elated! ====

I'm happier than a clam at high tide! Now I have a whole host of experiments I'm wishing to do because I want to test and verify for myself a lot of questions along the lines of "what will happen if I do x" and I needed to know this particular line of code. The other solutions worked when I ran them in codeblocks (although not in the cloud ide that CS50 uses) but I didn't fully understand what I was seeing nor how to tinker & substitute my own memory addresses into the code, which is fine for now.

The other great thing I really like about computer programming is the absolute freedom you have to write and instruct the computer to do anything you want β€” no questioning, no second-guessing, no backtalk β€” especially if you are the type of person who gets joy at telling the computer to perform purposeless tasks. Thanks again, everyone! [[Special:Contributions/67.233.34.199|67.233.34.199]] ([[User talk:67.233.34.199|talk]]) 11:57, 1 January 2018 (UTC)


== Who or what can fix corrupted and unplayable video files? ==
== Who or what can fix corrupted and unplayable video files? ==

Revision as of 11:57, 1 January 2018

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December 24

Electrical contacts on bottom of Intel Core CPU

Bottom of Intel Core CPU

On the bottom of an Intel Core CPU, are all of these things electrical contacts or only ones inside the smaller rectangle? Bubba73 You talkin' to me? 01:05, 24 December 2017 (UTC)[reply]

LGA 1155 seems to say that the things outside the smaller rectangle are the electrical contacts. Bubba73 You talkin' to me? 01:22, 24 December 2017 (UTC)[reply]
The stuff in the middle are SMT components. If you look at the socket on the motherboard, it should be obvious where the pins are that make contact with the CPU. Nil Einne (talk) 04:37, 24 December 2017 (UTC)[reply]
A picture of a CPU socket may help clarify things. https://upload.wikimedia.org/wikipedia/commons/thumb/d/d9/SocketA.jpg/1200px-SocketA.jpg Those pins you see on the outside of that CPU enter the little holes you see in the socket. Here is a photo of an old CPU with the pins clearly visible https://en.wikipedia.org/wiki/File:Intel_80486DX2_bottom.jpg (((The Quixotic Potato))) (talk) 06:48, 24 December 2017 (UTC)[reply]
Resolved

Bubba73 You talkin' to me? 19:05, 24 December 2017 (UTC)[reply]

We're talking about modern Intel desktop processors with LGA sockets. The CPUs do not have 'pins' and the sockets do not have 'holes' under most ordinary definitions of those words. As stated, the motherboard socket should have what are generally called pins, although they are of different design than PGA style pins on AMD desktop CPUs and older Intel CPUs. The CPU doesn't really have what would be called holes, but simply pads, so really there are no holes involved in the contacts (unless you refer to the design of the pins). Nil Einne (talk) 04:58, 26 December 2017 (UTC)[reply]
Land grid array: Unlike the pin grid array (PGA) interface found on most AMD and older Intel processors, there are no pins on the chip; in place of the pins are pads of bare gold-plated copper that touch protruding pins on the microprocessor's connector on the motherboard. (((The Quixotic Potato))) (talk) 05:47, 26 December 2017 (UTC)[reply]
Which is what I said. Nil Einne (talk) 16:19, 26 December 2017 (UTC)[reply]
I wasn't disagreeing with you, just providing the relevant text from the Wikipedia article with links for those who want to read more. (((The Quixotic Potato))) (talk) 17:09, 26 December 2017 (UTC)[reply]

December 25

2-in-1 Software

An opensource software that allows you to use two PC mouses together, one for the left hand's purpose and one for the right hand's purpose. Can you help me please? 123.108.246.98 (talk) 18:52, 25 December 2017 (UTC)[reply]

There is no easy solution. See here. Ruslik_Zero 19:33, 25 December 2017 (UTC)[reply]

Clogged websites

I've noticed recently that many websites are overloaded by advertisement to a degree that they get frozen when you attempt to change a page. Just try Amazon.com[1]. The first thing that strikes your eyes is a huge banner "Steelers vs. Texans." I understand ads bring money but I think Jeff Bezos, the richest man alive, could provide some living space for the website users. Amazon.com is no exception. Try Cnn.com, msn.com, the websites I visit to get information about what is happening in the world. The same thing. My computer has not become slower and I run antispyware applications regularly. When is it going to end? Internet is becoming unusable. AboutFace 22 (talk) 20:58, 25 December 2017 (UTC)[reply]

I have the same problem with a slow computer and a slow internet connection. Perhaps, before long, we will be expected to pay for advertising-free content. Fortunately, Wikipedia doesn't do advertising. It really annoys me when a webpage goes off to lots of advertising sites before displaying the content that I want to see. I assume that the coding is done deliberately to display adverts first. Dbfirs 21:09, 25 December 2017 (UTC)[reply]
Have you tried installing an ad blocker? Rojomoke (talk) 22:20, 25 December 2017 (UTC)[reply]
NoScript (or similar) goes a step beyond and blocks the useless bells and whistles that don't want to sell you stuff, too. InedibleHulk (talk) 22:36, December 25, 2017 (UTC)
"Fortunately, Wikipedia doesn't do advertising" ... From my experience, Wikipedia has a permanent nearly full-page ad at the top of every page begging everyone to send in money. I click hide, but it doesn't hide. It comes back as soon as I go to another page. 71.85.51.150 (talk) 23:13, 26 December 2017 (UTC)[reply]
You can get rid of that if you create an account. Dbfirs 00:15, 27 December 2017 (UTC)[reply]

Any personal experiences? Do the ad blockers work well? AboutFace 22 (talk) 02:51, 26 December 2017 (UTC)[reply]

I can vouch for Adblock_Plus, without which many sites are unusable. They also have a policy of whitelisting some advertising that is less obtrusive, so the site can still pay its bills. As to whether the ads load first deliberately, I'm not sure if that's by design, or if it's that ads are often served by third-party sites, and browsers start to load that type of content before loading the rest of the site itself. OldTimeNESter (talk) 04:13, 26 December 2017 (UTC)[reply]
Some sites do try to force the browser to load ads first, however the combination of Adblock Plus, NoScript and Stylish for the occasional webpage trying to use CSS to deter ad blocking should make nearly any site usable. 93.142.65.4 (talk) 18:39, 26 December 2017 (UTC)[reply]

Thank you much. Will try your advice. AboutFace 22 (talk) 20:05, 26 December 2017 (UTC)[reply]

December 27

Help Translating Phone Specs Into Quality Of Experience For VR

So, for something to do over the winter months, I decided I wanted to buy either an S8, S8+, or Note 8 and a Gear Headset to play with VR. Trying to determine which of the three would give the best experience got me curious in general about how much of a factor screen size plays in the experience. For example, all three phones have the same resolution, but they each have a different size screen - from what I have seen online, people say that the smaller screen will have a higher pixel density, thus a better image. Which leads me to my question: while it does make sense that higher pixel density would look better, in what other ways would the image look different (in the headset) compared to the larger screen? Ultimately, a larger screen will have a larger area devoted to the same piece of the image, so, it would take up more of your field of vision - thus, would you see more of the scene on the smaller screen than the larger screen? Would this effect quality? Does ppi strongly determine quality at the resolution of these phones? I'll admit, since this is going to be an almost $1000 purchase, I would like to get the highest quality experience; but, not being able to find a great deal of quality information, I'm, now, curious in general about what factors contribute to quality, and in what way.

To continue on this topic, I bought a very cheap $20 headset at Walmart and played around with my friends Note 8 for about an hour; would the more expensive Gear Headset have provided a better quality experience? In short, what does the headset contribute? How does it effect quality? Apologies if these are vague questions, most of the information I can find is just enthusiasts not saying anything technically clear or reviews of the devices as phones or spec sheets - I'd like to get a better understanding of the what's, how's, and why's of the different factors.

General interest aside, I have two (additional) questions that would help with my actual purchasing (if anyone is inclined to chip in on that note). I read online that the Note 8 doesn't default to its maximum 1440 resolution, but instead 1080 - I highly doubt that my friend adjusted this, so would the VR video player I installed have used 1080 or 1440 for the display? I ask since I wasn't that overly impressed with some of what I watched, but I'm not sure if this is because of the headset, because it just isn't that developed yet to give good results, or because the display was forcing a lower res than the video. And: supposing the smaller screened S8 (or S8+) would give a better experience because of higher ppi, would it be worth it over the Note 8, despite that the Note has an extra 2Gb of ram (in short, would the extra ram give a smoother experience and ensure there is less/no lag or stutter when running more intensive vr apps or videos)?

A final curiosity: Does a 360 VR video have lower quality than a 180 VR video? In other words, does the resolution of the video mean over some set angular area or over the whole video? Since if it is over the whole video, the area behind your head would be using some of the pixels that a 180 version could devote to the front - is that accurate? I ask since I watched a handful of videos and did notice some differences in quality, despite all of them having the same listed resolution; I'm not sure which were which, since I didn't have a lot of time to test, but I came up with this hypothesis when I was driving home, I was curious if it was correct.

I know there are a lot of questions here, I'm really just looking for any information beyond the vague accounts gotten from forums posts; thank you for reading:-) β€”Β Preceding unsigned comment added by 24.3.61.185 (talk) 10:44, 27 December 2017 (UTC)[reply]

πŸ˜‚

How does one type πŸ˜‚ without copy/pasting it from somewhere? When I'm sending a Facebook message, I can type πŸ™‚ by simply doing :-) and the messenger converts it to πŸ™‚. However, I don't know how to type πŸ˜‚ and don't expect to (I just encountered it a few minutes ago for the first time), and it seems like it would require a rather complex emoticon. Maybe it's a smartphone thing (I have a Samsung SPH-M400; no article); do smartphones have a Chinese-characters-like thing where you supply a name and it gives you a list of related emojis? Nyttend (talk) 22:58, 27 December 2017 (UTC)[reply]

That's U+1f602. How you'd enter it depends on your OS' Unicode input method. On Linux, I did Ctrl+⇧ Shift+u, release, 1f602↡ Enter -- Finlay McWalter··–·Talk 23:09, 27 December 2017 (UTC)[reply]
Of course, in practice, real people don't memorise pages of obscure unicode codepoints for weird icons they almost never use. Either you are stuck with cut and pasting it from somewhere, or your device has a menu which lets you browse through lists of such things. -- Finlay McWalter··–·Talk 22:28, 28 December 2017 (UTC)[reply]
On Windows 10 you can enable the onscreen keyboard, which lets you input any emoji you want by clicking on it -- 83.142.58.162 (talk) 14:46, 29 December 2017 (UTC)[reply]

Related, Category:Samsung mobile phones has almost 300 articles, including SPH M100, M300, M310, M520, and M620. Where would I find references for an M400? A quick Google search found lots of informal sites like the one I linked above, but I couldn't find anything to support an article; it would be nice to have an article (I could supply a picture) if someone knew where to find the sources. Nyttend (talk) 23:00, 27 December 2017 (UTC)[reply]

https://www.cnet.com/products/samsung-m400-sprint/preview/
https://www.pcmag.com/article2/0,2817,2412938,00.asp
https://www.samsung.com/us/support/owners/product/m400-sprint
(((The Quixotic Potato))) (talk) 06:59, 28 December 2017 (UTC)[reply]
@Nyttend: see above. (((The Quixotic Potato))) (talk) 19:48, 29 December 2017 (UTC)[reply]
@Nyttend: Try using emoticons :'‑) or :') (based on Wikipedia's article List of emoticons). --CiaPan (talk) 21:56, 29 December 2017 (UTC)[reply]

December 28

I have 2 questions about 2 different websites

1. Why is the Box office and Business button on the imdb's website on movie pages anymore? I would like to see a movie's filming dates? 2. Is this website in this link a reliable website where I can buy Xena merchandise because I emailed the person on link and it the mail address didn't work: http://www.alaska.net/~rlw/warriorhome.htm 50.68.252.153 (talk) 05:38, 28 December 2017 (UTC)[reply]

Regarding the IMDB, the buttons on their web site are their business. We don't know what they were thinking when they decided to have them. Filming dates are not something they routinely provide and I don't know any source for this information elsewhere. --76.69.117.217 (talk) 05:51, 28 December 2017 (UTC)[reply]
The link to this person's eBay auctions is also dead. I'd look somewhere else.OldTimeNESter (talk) 17:56, 28 December 2017 (UTC)[reply]

Problems with Windows 10

The other day I looked at the article Criticism of Windows 10 to see whether other people have the problems that I am having, and found none of them. So I made a list of them on the talk page, asking whether anybody can give references for these things so we can put them in the article (see my list). My talk page entry was immediately deleted by a certain person on the grounds that I was using the talk page as a forum. I protested that she didn't have the right to do that, and in the end took it to the Administrators' noticeboard. Someone there (see Wikipedia:Administrators' noticeboard/IncidentArchive972#Removal of a request on the Talk page of Criticism of Windows 10 suggested I bring up my request here. I'm not sure it's appropriate here, but I'm following his advice. Please Ping me if you answer! Eric Kvaalen (talk) 07:53, 28 December 2017 (UTC)[reply]

Hi.
You are in the right place.
However, correctly asking your question is an art. First, you should copy and paste your list here. Having people hunt for it reduces your chance of a getting reply. Second, you should filter out non-question items. For example, the following is not a question: "Windows 10 came with a Mail app that is a disaster. I won't bother saying what's wrong with it because of course you don't have to use it. I managed to get Windows Live Mail to work instead." Third, you should avoid linking to drama, such as ANI. It makes people dismiss your question as something with ulterior motivations.
Finally, you are in the weakest of the right places. As I told you, asking it in Microsoft Answers, TechNet Forum or Superuser.com is much more helpful. However, judging by your list, you are in serious need of technical support. That, and a good book about Windows 10 and its features. You could use some familiarity with new features of the operating system.
Best regards,
Codename Lisa (talk) 10:28, 28 December 2017 (UTC)[reply]
It turns out there are people like me in this Universe. I opened up this Computer Desk with a resolution to complain about Microsoft and Windows 10. This is one of them. I have Google browser on my desktop. I prefer Google. I click on the icon and Google browser shows up. I enter a web address in the top narrow window and click CR. I get a white screen with a few sentences. I give you an example when I tried to open The Wall Street Journal front page[2]. This is what I see.
Of course it is a lie. IT IS A LIE. I click on this link now and get a bunch of various ads and links which I better avoid using, but the "https://www.wsj.com" is one of them and finally I get my newspaper after jumping through some hoops. Why does Microsoft do it? Because they make money on their own advertisement on Bing but not when the ads appear in Google. Is it a result of the fact that the Internet Fairness act has been repealed?
The problem when the whole computer freezes with overload by advertisements is simply an icing on this rotten cake. AboutFace 22 (talk) 21:02, 28 December 2017 (UTC)[reply]
This isn't the right place to complain about anything. The closes I can see in what you say would be to rephrase as why does your computer freeze when you do xyz. Dmcq (talk) 19:18, 29 December 2017 (UTC)[reply]
The problem is in your computer, not in Win10. First, 2Gb is quite low for Windows 10. I recommend 4 GB minimum. Second, your hard drive may be not in good shape. You should check it for errors. Third, you may have some malware installed. You should check your computer using an antivirus software. Ruslik_Zero 19:31, 29 December 2017 (UTC)[reply]
I find that 4GB is quite small - in my experience, it spends a lot of time swapping memory to HD with only 4GB. I would certainly go beyond 4GB. At least add 4GB to get to 6GB and at least 8GB will be better. Personally, I have a minimum of 16GB, but that is me. Bubba73 You talkin' to me? 01:42, 30 December 2017 (UTC)[reply]
Do you have Defragmenter turned off? Have you defragmented recently? Fragmented files can significantly increase launch times and file retrieval time from the hard disk. To check your setting and run the defragmenter: Click Start button; scroll to Windows Administrative Tools and click it; click Defragment and Optimize Drives. My experience is that every time Win10 downloads and installs a really big update, as it did recently, Defragmenter must be run very soon after, apparently because many existing files are moved in fragmented fashion so that the update files can be installed unfragmented. Akld guy (talk) 00:46, 30 December 2017 (UTC)[reply]
@Eric Kvaalen: Pinging as you requested to ensure you don't miss the replies! You should better hope mw:Extension:StructuredDiscussions to be adopted on pages like this when it leaves beta and gets deployed in enwiki. It takes care of notifying users, you see!Β :) - - Kaartic correct me, if i'm wrong 12:49, 30 December 2017 (UTC)[reply]
@Akld guy, if your suggestion about defragmenting was aimed at me, then NO, my disks are all 0% fragmented. AboutFace 22 (talk) 16:26, 30 December 2017 (UTC)[reply]


This is Eric again. I will answer here to all the above. First of all (to Codename Lisa) the person who advised me to put my question here said I should make it much shorter. So I just put a link to my list instead of listing all the problems again. And my question was not "How can I solve these probllems", (though I wouldn't mind someone telling me if he or she knows how to solve one or more of these problems), my question was do other people have these problems and if so what can we use as sources to modify the Criticism of Windows 10 article! I think it's really bad on the part of Microsoft to give us such a rotten Mail app with Windows 10. It would do things like committing suicide (disappearing from my tasks) when I was in the middle of writing a letter! (I had closed my laptop to take a train, and when I woke it up that Mail app was closed and my letter had vanished.) I had used Windows Live Mail in the past, and they sent me an e-mail saying it would no longer work with Hotmail. Which after a year or two of suffering with the Windows 10 app I discovered was a lie – you just have to configure the mail server in Windows Live Mail a bit differently! Finally Lisa, the reason I linked to "ANI" was that I didn't think putting this question here was the right thing to do, so I was giving my excuse for doing it.

Oh, and Lisa, as to me being in serious need of technical support, I mentioned that I have had these problems from Day One. It's not due to viruses or something. (Maybe some of the problems are due to the McAfee that came with the computer, but only part of the problems.) And what do I need to study the new features for? I just want to use my laptop for Internet browsing, text processing, mail, and spreadsheets. As I would do decades ago with Windows 3 just fine.

Now, Ruslik0, I don't know whether you were writing for me or for AboutFace 22. I'm the one who has only 2 Gibibytes of RAM. I once had a computer with 4, but otherwise I've always had 2 or less. (Much less in the olden days!) And the versions of Windows I had then worked better. Bubba73, I don't see why I should have a lot of RAM when I'm not doing anything in particular. It's as though they've made Windows much less efficient. I'd be surprised if my hard drive has errors. As I have said, I've had these problems form the very beginning of using this computer. Same thing for malware. (Note added later: I've just tried checking my disk for errors and I immediately get a message that says "You don't need to scan this drive. We haven't found any errors on this drive. You can still scan this drive if you want.")

Akld guy, I never turned off any defragmenter. But of course a fragmented disk wouldn't be the explanation for why I had these problems when I first got this computer and put Windows 10 on it. My disk is mostly empty. Anyway, I've just checked the way you suggested, and it says my partitions are 0% or 1% fragmented, and "scheduled optimization" is "on", with frequency "weekly".

And Kaartic, thanks for Pinging me. No one else did.

Eric Kvaalen (talk) 20:32, 30 December 2017 (UTC)[reply]

Windows 10 will run with 2GB but even Microsoft recommends 4GB. You say that the old versions of Windows worked better. having more RAM will help a Windows 10 computer.
Here are two YouTube videos.
The first one compares 4, 8, and 16 GB. Sometimes extra RAM makes essentially no difference but sometimes it makes a huge difference. It recommends 8GB. The second video discusses it, but I haven't watched the whole thing. Bubba73 You talkin' to me? 21:14, 30 December 2017 (UTC)[reply]
The complaint list has indicators that RAM isn't the problem here. On similar hardware, Windows 10 is faster than Windows 7 (but slower than Windows 8); that's a fact. Furthermore, the complaint list mentions high CPU and disk I/O traffic. While the I/O traffic by System can be attributed to paging, high CPU usage and high disk I/O by other processes cannot be alleviated by more RAM.
In addition, the complaint list says the system sometimes comes to full halt; the Start menu does not open smoothly and File Explorer doesn't launch reasonably fast. And the context menu doesn't appear on command either. All of this point either software bloat or malware infection. Even on a system with the minimum hardware requirements, Windows responds smoothly. Finall, the Alt+Tab complaint is very suspicious; it either means something has hijacked it or Eric is running a very old version of Windows 10 (maybe a beta version).
Also, there are other things to consider: The user in question delays coming here; when he comes here, he is not actively watching the thread for an answer; he'd rather talk back than cooperate in solving the problem. Therefore, I am not ruling out that this whole hoopla is just for throwing mud at Windows 10. Mind you, I am not saying I am against it. I am saying Wikipedia is not a battleground.
Best regards,
Codename Lisa (talk) 09:50, 31 December 2017 (UTC)[reply]

Regarding IMDB

Is there a way I can contact the people who run the IMDB? 50.68.252.153 (talk) 09:22, 28 December 2017 (UTC)[reply]

Have you tried http://www.imdb.com/helpdesk/contactΒ ? --Phil Holmes (talk) 10:11, 28 December 2017 (UTC)[reply]

In Wikia, searching all pages that are in two categories

In a Wikia website like http://disney.wikia.com/ , is there any way to search all pages that are simultaneously in two categories? --Daniel Carrero (talk) 22:14, 28 December 2017 (UTC)[reply]

Search for a random string that doesn't have a result. Click on the Advanced link to the right-hand side of the page. In the revealed area, click the Sections you wish to search in. LongHairedFop (talk) 14:14, 29 December 2017 (UTC)[reply]

December 30

LED screens for portable electronic devices that are not OLED

Could screens for portable devices be composed of a array of really small LEDs (but without organic components like OLED)? That is, not back illuminated by LED, but each pixel consisting of a micro LED. I only know LED screen in outdoor displays.--Hofhof (talk) 01:29, 30 December 2017 (UTC)[reply]

Yes. The problem is that the smallest LEDs are far too large to make a display that anyone would want to use. Instead, you'd have to create a sheet of LED-like molecules that you can independently ionize to create light. In other words, you'd just be reinventing the OLED display. 71.85.51.150 (talk) 03:24, 30 December 2017 (UTC)[reply]
They are working on that right now FΓ«anor Engineering (talk) 11:10, 30 December 2017 (UTC)[reply]

GUI ambiguity

I've been using google hangouts recently. This has a button marked "mute" (with a picture of a microphone with a line through it). But I never know whether this means "press this button to mute your mic", or "your mic is now muted, press this button to unmute". I see this very annoying ambiguity very frequently, in many contexts (not just sound). Is there a name for it? Robinh (talk) 02:00, 30 December 2017 (UTC)[reply]

Apparently the problem is not just you: [3].
Does the button change color/form/sign when you press it? Does it display any text?--Hofhof (talk) 02:52, 30 December 2017 (UTC)[reply]
Heh, good to know it's not just me. But the problem is universal: for example on my ubuntu box, for bluetooth, there is a toggle switch with two settings: "on" or "off". Does "on" mean "bluetooth is currently on, press this button to turn it off", or does it mean "bluetooth is currently off, press this button to turn it on"? Or is this obvious to most people? Robinh (talk) 03:54, 30 December 2017 (UTC)[reply]
The controls are called "flip-flop buttons" in Alan Cooper's book About Face: The Essentials of User Interface Design.[4] The problem itself is common, but I don't know if it has a specific name. Mitch Ames (talk) 13:34, 30 December 2017 (UTC)[reply]

(OP) Thanks for this Mitch. The stackoverflow page is great: very nearly all the posters understand the problem, and most despair of unthinking and confusing UI design. As far as actual usage is concerned, it seems that in about half of interfaces, "on" refers to the state and in rest "on" refers to the action. Robinh (talk) 18:50, 30 December 2017 (UTC)[reply]

Privacy violation (or) Missing Terms of Service - what action to be taken?

On my birthday (that happened a month ago), I received an SMS to my "personal" mobile number from a travels related website. The message wished me a happy birthday (specifying my age) while giving me an offer of 10%. This shocked me more than it surprised me for the following reasons,

  1. I have no idea about that website up and until I got that message
  2. I don't disclose my personal mobile number or my birthday unnecessarily. The fact that they got my Name, DOB, Phone number correctly was a great shock!

I tried to narrow down the potential services that I use which might have gave my personal information to that website. I was able to narrow it down to one service. It's a service I use to book train tickets in my country (India). I was even more shocked when I came to know that I was using a service which neither had a "Privacy Policy" nor a "Terms of Service"Β !

I even pinged them about the lack of Privacy Policy a month ago but no reply (except for the automated reply) until now. I'm pretty sure that they would be the one who would have given out my information without my consent. I would like to take action against them. Further even if the service isn't behind the SMS I got on my birthday, I would like to take action against them for not having a Privacy Policy or ToS. I'm not sure how to go about it. Any guidance as to what I could do about this "privacy information leak without permission" or "missing Terms of Service" issue would be helpful.

Note: If this isn't the right place to ask, please point me to the right locations if possible. - - Kaartic correct me, if i'm wrong 18:18, 30 December 2017 (UTC)[reply]

I am not sure why you are asking here? This is a "computer desk" intended for question related to computers. Ruslik_Zero 20:13, 30 December 2017 (UTC)[reply]
You are not why answering Good English Ruslik. The "computer desk" not intended ungrammatical criticism. μηδΡίς (talk) 20:33, 30 December 2017 (UTC)[reply]

@Kaartic: You can try [this consumer protection link] which deals with unsolicited SMS communications and is linked to by the Telecom Regulatory Authority of India's main website. You can also call your phone service provider and ask for a number for regulatory complaints/inquiries regarding uninvited solicitations or talk to a lawyer. μηδΡίς (talk) 20:33, 30 December 2017 (UTC)[reply]

December 31

C programming β€” how do I view the 8, 32, or 64 bits of binary information at a known memory address?

  • "Main memory or RAM is arranged as an array of "sets of electronic on/off switches" or locations beginning at address 0. Each location can store usually 8, 16, 32 or 64 bits."
  • "Memory can be thought of as an array of bytes where each address is one index in the array and holds 1 byte."
  • My final attempt of getting help before coming here to the ref desk! Τ„

I'm an absolute beginner. I just joined codeacademy last month and more recently I've enrolled in Edx's premiere computer science class CS50! I just learned through wikipedia how to find the memory addresses of any data type just by typing "%p, &shark inside the printf function and now I'm like a giraffe who discovered the stepladder!

Is there a clean, fool-proof way for me view the 8, 16, 32, or 64 bits of ANY memory location just by having that memory location's address? (e.g. 0x7ffed73897d8) In other wordsβ€”if I know the addressβ€”is there a program or line of code which can "print for me the 8, 16, 32, or 64 bits of binary information" at the known address? 67.233.34.199 (talk) 03:03, 31 December 2017 (UTC)[reply]

Here's the thing: all data in any typical computer is binary. Any time you're printing output, you are "printing binary information". Your code just usually tells the computer to interpret said data in a particular way, such as an integer value within a certain range. This is a thing a lot of beginning programmers have trouble wrapping their heads around. Computers are dumb. They don't know what a "number" is. They just process data according to the instructions they're given. If you tell the computer to interpret a value as a 32-bit signed integer, it will do that. If you tell it to interpret it as a name in a database, or a pixel in an image, it will do that. Now a second thing: on most modern computers, you can't arbitrarily access memory addresses in a program. The reasons take a while to explain in detail, but they have to do with virtual memory and operating system access controls. You usually can view a process's memory contents with a debugger, and sometimes other ways as well, like through the proc filesystem on Linux. (Sometimes this requires administrator privileges.) If you do want to play around in an environment where you can access arbitrary memory, try an emulator for a platform without memory protection, such as Dosbox.
Anyway, to sort of answer your question, C gives you types for accessing fixed bit-width values, instdint.h. Note this requires C99, but if you're trying to learn in an environment without C99 support, throw it out and use one that does. Note you will see a lot of stuff online telling you to do things like use a char* to read a single byte. This is wrong in plain C because the size of types like char is platform-dependent. Using char as a synonym for "8-bit byte" was common in pre-standard C, and old habits die hard. With that said, POSIX does mandate char be exactly eight bits, so if you're writing explicitly for POSIX platforms you can assume that. Here's an example for looking at a 32-bit chunk of memory. As I said, on modern platforms you can't access arbitrary memory addresses, so instead we're just going with whatever the operating system gives us off the heap with malloc.
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
int main() {
	uint32_t *ptr = malloc(sizeof(uint32_t));
	if(!ptr){return 1;}
	printf("Value: 0x%x Address:0x%x\n", *ptr, ptr);
	free(ptr);
}
This prints the value and address pointed to in hexadecimal. C has no built-in support for printing values in binary because it's rarely useful; hexadecimal is what programmers usually use for displaying "raw" data. As a teaching exercise, you can try using this macro for binary output. For pedagogical value, I've done things right by checking for malloc failure, and freeing the malloced memory after using it. Obviously this isn't necessary in a toy program, but in "real" programming you should always do these. Note as well that forgetting to assign something to a malloced pointer is a common mistake. Here it isn't a mistake because we want to see whatever's in the memory location already. It's possible that you might always get a value of 0, because these days it's increasingly common for systems to zero out memory when it's allocated by a process. --47.157.122.192 (talk) 10:48, 31 December 2017 (UTC)[reply]
Oh, and here's a fairly good Wikibooks page on stdint.h. --47.157.122.192 (talk) 11:24, 31 December 2017 (UTC)[reply]
In addition to the reliable types defined in stdint, inttypes.h defines reliable printf format specifiers for the same specific sizes. So:
#include <stdio.h>
#include <inttypes.h>
#include <stdint.h>

void print_values(uint64_t* p){
  printf ("values at %p:\n", p);
  printf (" 8 bit:  %02"   PRIx8  "\n", (uint8_t)*p);
  printf (" 16 bit: %04"   PRIx16 "\n", (uint16_t)*p);
  printf (" 32 bit: %08"   PRIx32 "\n", (uint32_t)*p);
  printf (" 64 bit: %016"  PRIx64 "\n", (uint64_t)*p);
}

int main () {
  const char test_data[] = { 0x12, 0x34, 0x56, 0x78,
                             0xf1, 0xe2, 0xd3, 0xe4 };

  print_values((uint64_t*)test_data);

  return 0;
}
-- Finlay McWalter··–·Talk 11:09, 31 December 2017 (UTC)[reply]
In fairness I should note that inttypes.h is a C99 feature, and MSVC's support for C99 has been patchy. It seems they added support for this in the 2013 version (but I've not personally tested this on that platform). -- Finlay McWalter··–·Talk 14:59, 31 December 2017 (UTC)[reply]
Yes, that's the right way to do it. For some reason I was thinking printf did some magic with the width of its arguments. Moral of the story: 1 AM is not the best time to program. --47.157.122.192 (talk) 21:37, 31 December 2017 (UTC)[reply]


I think the bigger problem here is that, given memory protection, memory virtualization, address randomization and other such things, there may not even be an address "0x7ffed73897d8" from which you can read. If you absolutely, positively need to read from an address given as a literal, you cast that literal into a desired pointer type and use the pointer to obtain the value stored at that address (i.e. dereference it), like this:
printf("%d\n",*(int*)0x7ffed73897d8);
This is it, as far as C is concerned, but see above. Your program will most likely crash. In simpler systems running on simpler hardware, such as DOS running in real mode, this was, however, a totally "legit" way to access memory at known addresses, for example in order to write to the video memory or to read the BIOS data area that contained various useful info about the computer (such as the number of floppy drives or COM ports and their respective addresses.) 78.50.124.31 (talk) 20:38, 31 December 2017 (UTC)[reply]
I take it your misconception about memory stems from the phrasing "can be thought of as an array... at location 0." This is a simplification, but good for you thinking ahead, apparently you're the first participant of your course to do so 78.50.124.31 (talk) 20:59, 31 December 2017 (UTC)[reply]

C programming β€” "printf("%d\n",*(int*)0x7ffed73897d8)" worked and I'm elated!

I'm happier than a clam at high tide! Now I have a whole host of experiments I'm wishing to do because I want to test and verify for myself a lot of questions along the lines of "what will happen if I do x" and I needed to know this particular line of code. The other solutions worked when I ran them in codeblocks (although not in the cloud ide that CS50 uses) but I didn't fully understand what I was seeing nor how to tinker & substitute my own memory addresses into the code, which is fine for now.

The other great thing I really like about computer programming is the absolute freedom you have to write and instruct the computer to do anything you want β€” no questioning, no second-guessing, no backtalk β€” especially if you are the type of person who gets joy at telling the computer to perform purposeless tasks. Thanks again, everyone! 67.233.34.199 (talk) 11:57, 1 January 2018 (UTC)[reply]

Who or what can fix corrupted and unplayable video files?

I don’t know if this is an appropriate place to post this or if I should frame the question differently. I’m going to go ahead and explain and ask. I recently went on a trip where I took a lot of videos. I have a USB drive that you can put in to an iPhone on one end and the computer on the other end. To free up some space on my iPhone to continue recording, I moved some of the video clips directly to the USB drive. However, when I returned home and started going over the videos I put in my USB drive, my computer and my iPhone were unable play the videos except for the first few. 9 of the videos won’t even copy and paste to my computer. Is such an issue fixable? Who are what would be able to fix corrupted/unplayable videos? Willminator (talk) 03:22, 31 December 2017 (UTC)[reply]

Did you check the file system on your USB drive for for errors? Ruslik_Zero 16:41, 31 December 2017 (UTC)[reply]

iPhone and Android smartphone

Apple's iPhone don't have memory card slot. It's RAM is not more than 1gb (5 or 4 model). It's screen size is smaller than Android phones. Inspite of all these factors people buy it at awesome prices! (Which are far far higher than Androids having all I have just mentioned).Why is that? No, it can't be just brand mania. Or is it? Β Jon AsctonΒ Β (talk) 07:02, 31 December 2017 (UTC)[reply]

One assumes people buy it because they like it better than competing products. As for why, you'd have to ask them. Please note the page header, which states that we don't accept requests for opinions, predictions, or debate. I will note that at least in the U.S., iPhones and top-end Android smartphones are priced comparably. For instance, the iPhone 8 Plus MSRP is $799, while that of the Samsung Galaxy S8+ is $824.99. --47.157.122.192 (talk) 11:00, 31 December 2017 (UTC)[reply]
Neither 5 nor 4 models are sold now. Ruslik_Zero 16:46, 31 December 2017 (UTC)[reply]

January 1