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July 9

Line Mode Browser?

I am interested in running Line Mode Browser on the latest version of Windows 10. Has anyone ported it? Failing that, has anyone ported it to an environment that has an emulator for Windows 10? I can't find a compiled version that runs on anything. Yet the image on our Line Mode Browser page shows that someone managed to read Wikipedia using it... --Guy Macon (talk) 12:10, 9 July 2017 (UTC)

If you have a 32-bit version of Win10, you can try the 2002 distribution. It fails on a 64-bit version. Ruslik_Zero 21:00, 9 July 2017 (UTC)

I was able to run comline.exe on Windows 10 x64. The installer in the above location will not run properly, as it uses a 16 bit Installshield. A very common problem with old applications that affects all x86-64 versions of Windows including XP and also ReactOS. (Just do a search for 16 bit installer and probably all results will be about the issue.) If you run it, it should extra the install files into a temporary directory before Windows tells you it can't run. You can then follow these instructions [1]. It seems to be Installshield 3 so assuming you trust Toastytech you can get a replacement 32 bit installer here [2]. If you don't well trust them, well I doubt the LMB really needs to be installed so you just have to find some way of extracting the files. Or alternatively install it on a VM and recover the files. (In that case you don't even have to use Toastytech, just some version of windows with support for 16 bit executables.) Note that the screenshot was from 2010. I doubt you can access wikipedia anymore simply since it went HTTPS only and I'm pretty sure the above version doesn't support HTTPS. You could of course use some sort of HTTPS to HTTP proxy. Nil Einne (talk) 06:12, 10 July 2017 (UTC)

Thanks! I am expecting a lot of things not to work. Running a browser that old is a lot like teaching a dog to walk on his front two legs or asking a politician to give you a straight answer; the wonder is not that he does it well, but that he does it at all. :) --Guy Macon (talk) 06:27, 10 July 2017 (UTC)

A desired software(s)

I wish to type datas in the PC than transfer it to the Smart Phone, vice versa (also wish to type in the Smart Phone than transfer it to the PC), off-line. Could you refer me to any apps that could be synchronised using WiFi and or as well as Bluetooth in order to perform stated task

The following is what I seek: MS Outlook’s Calender, Tasks, Notes, Contacts.

Note: I’ve used many apps but ‘writing on PC than transferring it to the Smart Phone, also writing it on the Smart Phone than transfer it to the PC’ is a desired thing, what I’m unable to find. Could you refer me to something good please?

116.58.201.114 (talk) 15:52, 9 July 2017 (UTC)

Your question is too broad. There are a lot of ways to synchronize information between a smart phone and a PC. You can use, for instance, Google drive. Ruslik_Zero 20:48, 9 July 2017 (UTC)

Google Drive need on-line connection plus I'm not happy with it...

Okay:

Please refer me to an app(s) for creating "Tasks" and "Notes" - which consists of similar functionalities like MS Outlooks Tasks and Notes - that I could use or write, modify, amend, delete things in it in PC than transfer it to the Smart Phone using WiFi without internet on-line issue, also vice verse (i.e., write, modify, amend, delete things in it in the Smart Phone than transfer it to the PC using WiFi without internet on-line issue). 116.58.200.35 (talk) 16:33, 10 July 2017 (UTC)

Running quantiles - does this 'enriched' binary search tree have a name?

I am a hobby programmer, and I do not know all the terms of a pro computer scientist.

I have been thinking about the problem of maintaining k running quantiles, say over a window of. e.g., n = 8192 samples as computationally and memory efficient as possible. The samples coming in are quite unordered.

I realize, that if I only had to maintain a single running quantile, such as the running sample median, a good procedure would be to maintain a max-heap and a min-heap as priority queues, where the max-heap would be used for adding and removing elements with a values less than or equal to the current median, and the min-heap would be used for adding and removing elements with values larger than the median. By keeping track on the number of values added to either heap, elements can then be transferred along the way between the two heaps to assure they contain an equal number of elements (min heap one less for uneven sample sizes) and their roots can be used to find the median.

If I want to maintain k running quantiles, e.g., 10%, 20%,..., 90% (k=8). I could allocate k min-heaps and k max-heaps using k x n x sizeof(element) storage.

However, I am looking for an efficient solution, where I do not have to scale the memory and heap operations by a factor of k 'just' because I want to maintain k concurrent running quantiles.

For that purpose I tried to look into maintaining an 'enriched' binary search tree, where each node besides left and right references also has low and high references to nodes, which would refer directly to the next and previous nodes in a sorted list of all nodes, wothout having to traverse the tree in a classical tree search. This is convenient because the current quantiles can be maintained as k pointers to nodes containing the k running quantile values. If supplemented by counters to maintain how many elements are in the tree with values below each of the k quantile nodes, the quantiles can be maintained by moving it to quantile.high, if the sample count below the node becomes too small. Or point to quantile.lo if the number of sample points below the quantile node exceed the sample quantile.

It is not that hard to maintain the extra low/high pointers. I made a prototype implementation is Python where I just add values and maintain just a running median this way, and it seems to work. Here I have just the code for maintaining the 'enriched' BST tree when adding elements in order to not make things too complicated.

class Node:
    
    def __init__(self, data, lo=None, hi=None, left=None, right=None):
        self.data = data
        # Number of data values added
        self.count = 1
        # Linked list to Node with next lower value if all nodes were sorted
        self.lo = lo
        # Linked list to Node with next higher value if all nodes are sorted
        self.hi = hi
        # Node in binary search tree, with a lower value
        self.left = left
        # Node in binary search tree with a higher value
        self.right = right
        # If left and right nodes are None, the node is a leaf in the BST
        
            
class Tree:
    
    def __init__(self):
        self.root = None
        
    def add(self, data):
        if self.root is None:
            self.root = Node(data)
        else:
            current = self.root
            while True:
                if data < current.data:
                    if current.left is None:
                        nd = Node(data, lo=current.lo, hi=current)
                        if current.lo is not None:
                            current.lo.hi = nd
                        current.lo = nd
                        current.left = nd
                        break
                    else:
                        current = current.left
                elif data > current.data:
                    if current.right is None:
                        nd = Node(data, lo=current, hi=current.hi)
                        if current.hi is not None:
                            current.hi.lo = nd
                        current.hi = nd
                        current.right = nd
                        break
                    else:
                        current = current.right
                elif data == current.data:
                    current.count += 1
                    break

    def remove(self, data):
        ...

Now, this implementation is slow because

1. I need to allocate new/delete objects every time I add data
2. Creating objects in Python is just much slower than maintaining heapyfied lists

However regarding allocation, a fixed memory area of size n x sizeof(node data structure) could just be preallocated and a queue be maintained to keep track of vacant indices of nodes. Secondly this does not need to be implemented as objects, but can be maintained as lists of tuples of a fixed format.

As far as I can see adding/deleting a node is O(log(n)) (assuming the tree is fairly balanced, which is a reasonable assumption as the data I have in mind are unsorted on reception) and finding the lower/higher sorted element is O(1), so this seems very efficient for maintaining the k quantiles in O(log(n) + k) time.

I am sure I am not the first to consider such an 'enriched' binary search tree.

Does this kind of sequentially sorted binary search tree have a name?

Is there a better way to solve the same problem of maintaining k running quantiles?

-- Slaunger (talk) 20:42, 9 July 2017 (UTC)

In my opinion, memory is cheap, so store all the data in memory (you do it as heaps, but I would do it as an array). You can do an insertion sort as data comes in. Then, the 10th percentile is index floor(X/10) where X is how many items you've inserted. I do a lot of percentile queries on very large data sets (more than 10 million entries, often more than 100 million entries). My solution is consistently to sort and then hit index floor(X/10), floor(2X/10), floor(3X/10), floor(4X/10), etc... Sort is O(n log(n)). You claim your add/delete is O(log(n)) and you do it for n items. So, your overall algorithm is O(n log(n)). In both cases, hitting a specific index is O(1). So, I don't see a benefit to making a bunch of heaps when I could simply sort all of the data. 209.149.113.5 (talk) 13:30, 10 July 2017 (UTC)

Another way I could phrase my response, which may make more sense is to imagine smaller and smaller heaps in your solution, allowing more percentile calculations. Eventually, you will have one item per heap. You will have a sorted array. Your algorithms is just an insert sort, so why not insert sort a sorted array and you can pick out any percentile you want, such as the 23.7th percentile. 209.149.113.5 (talk) 15:17, 10 July 2017 (UTC)

And a comment about big O notation: It's a good first approximation of how efficient an approach will be, but then bench-marking shows which is really best. The "overhead" that's often neglected when using big O notation, such as allocating and deallocating memory, can be significant. StuRat (talk) 17:41, 10 July 2017 (UTC)

Javascript forum

Hello. I am coding some Javascript and I keep hitting a roadblock. Is there a forum somewhere that will allow me to post the troubling code and someone will tell me what I am doing wrong?    → Michael J Ⓣ Ⓒ Ⓜ 22:52, 9 July 2017 (UTC)

You can post it here, but the most popular site for such questions is Stack Overflow.—Best Dog Ever (talk) 23:30, 9 July 2017 (UTC)

Another alternative is [the codereview subsite of stackexchange.]--Hofhof (talk) 13:04, 10 July 2017 (UTC)

July 10

Javascript coding problem (cycling images)

OK, in light of the above answer, I will post my problem here, since I am more familiar with this place.

I am trying to get two buttons to cycle through a set of images. Button A should cycle through the images in the top box, and Button B should cycle through the same images in the bottom box. But what has happened is that both buttons cycle the top box.

What do I need to do so that each button cycles its own image set?

Here is the HTML coding:

<html>
<head>
  <title>Sample</title>
  
<script type="text/javascript" src="alpha.js"></script>
</head>

<body>

<div id="main">
<div id="content">

<div class="maintable">
<form action="none" method="post" id="basicForm">
<table border=1>
  <tr>
    <td><img src="image0.jpg" id="alpha" width="30px" /></td>
    <td><input type="button" value="A" onclick="changeImage()" /></td>
  </tr>
  <tr>
    <td><img src="image0.jpg" id="alpha" width="30px" /></td>
    <td><input type="button" value="B" onclick="changeImage()" /></td>
  </tr>

</table>
</form>
</div>
</body>
</html>

And this is the code for alpha.js:

var n = 0;
function changeImage() {
  if ( n == 0 ) { document.images["alpha"].src = "image1.jpg"; n = 1; }
  else 
  if ( n == 1 ) { document.images["alpha"].src = "image2.jpg"; n = 2; }
  else 
  if ( n == 2 ) { document.images["alpha"].src = "image3.jpg"; n = 3; }
  else
  { document.images["alpha"].src = "image0.jpg"; n = 0; }
}

(This is not going to be the end-all of the coding. But once I get through this puzzle, I think that I can continue my work without much trouble.)

Thank you.    → Michael J Ⓣ Ⓒ Ⓜ 00:11, 10 July 2017 (UTC)

You have two elements with the id of alpha - id must be unique. -- Finlay McWalter··–·Talk 00:20, 10 July 2017 (UTC)

As a general rule, there's not much point trying to diagnose problems with HTML code when the code is invalid. Run your code through a validator like HTML Tidy routinely (before you ever look at it in the browser) and you cut out all kinds of problems, including this one. -- Finlay McWalter··–·Talk 00:22, 10 July 2017 (UTC)

The problem is that both image tags have the same ID. There are several ways to code it, but here is how I would approach it with the HTML:

<html>
<head>
  <title>Sample</title>
  
<script type="text/javascript" src="alpha.js"></script>
</head>

<body>

<div id="main">
<div id="content">

<div class="maintable">
<form action="none" method="post" id="basicForm">
<table border=1>
  <tr>
    <td><img src="image0.jpg" id="alpha1" width="30px" /></td>
    <td><input type="button" value="A" onclick="changeImage1()" /></td>
  </tr>
  <tr>
    <td><img src="image0.jpg" id="alpha2" width="30px" /></td>
    <td><input type="button" value="B" onclick="changeImage2()" /></td>
  </tr>

</table>
</form>
</div>
</body>
</html>

And here is how I would code the JavaScript:

var n = 0;
function changeImage1() {
  if ( n == 0 ) { document.getElementById("alpha1").src = "image1.jpg"; n = 1; }
  else 
  if ( n == 1 ) { document.getElementById("alpha1").src = "image2.jpg"; n = 2; }
  else 
  if ( n == 2 ) { document.getElementById("alpha1").src = "image3.jpg"; n = 3; }
  else
  { document.getElementById("alpha1").src = "image0.jpg"; n = 0; }
}

function changeImage2() {
  if ( n == 0 ) { document.getElementById("alpha2").src = "image1.jpg"; n = 1; }
  else 
  if ( n == 1 ) { document.getElementById("alpha2").src = "image2.jpg"; n = 2; }
  else 
  if ( n == 2 ) { document.getElementById("alpha2").src = "image3.jpg"; n = 3; }
  else
  { document.getElementById("alpha2").src = "image0.jpg"; n = 0; }
}

—Best Dog Ever (talk) 00:25, 10 July 2017 (UTC)

Just avoid IDs in general. Use classes (even though you do something just 'once'). You'll write better code if you take the assumption that everything is an iteration over 0..n elements. Reserve IDs mostly for unique positions within your page, so that you can reach them with anchors in links, but not for JS operations. Also don't use onclick inside your HTML (it requires JS to access global variables, and current JS designs try to avoid global variables at all cost), add event handlers from the JS instead. The following is untested, but shows an approach that could be taken. This uses raw HTML/JS, it's a bit easier with jQuery. I'd probably use a few more classnames in a real life situation, since even this is making too many assumptions about the structure of a page (the usage of parentNode.parentNode, is a clear indicator of that). —TheDJ (talk • contribs) 09:32, 10 July 2017 (UTC)

<table border=1>
  <tr class="carousel" data-start="1" data-end="3" data-current="1">
    <td><img src="image0.jpg" id="alpha1" width="30px" /></td>
    <td><input type="button" value="A" /></td>
  </tr>
  <tr class="carousel" data-start="1" data-end="3" data-current="1">
    <td><img src="image0.jpg" id="alpha2" width="30px" /></td>
    <td><input type="button" value="B" /></td>
  </tr>
</table>

function step(e) {
    var element = e.currentTarget; // what element was clicked
    var carouselTR = element.parentNode.parentNode; // get the element for this carousel group
    carouselTR.dataset.current++; // we use data attributes to keep track of size and position in carousel
    if( carouselTR.dataset.current > carouselTR.dataset.end )
          carouselTR.dataset.current = carouselTR.dataset.start;
    img.src = "image" + carouselTR.dataset.current + ".jpg";
}
document.addEventListener( "DOMContentLoaded", function() { // once the DOM was loaded, modify it to add event handlers to our carousel buttons
    var elements = document.getElementsByClassName( "carousel" );
    for( int i=0; i < elements.length; i++ ) {
       elements[i].getElementsByTagName('input')[0].addEventListener( "click", step );
    }
} );

A site using an unsupported protocol

I suddenly cannot get to https://kpfa.org/archives/ because Chrome says "kpfa.org uses an unsupported protocol. ERR_SSL_VERSION_OR_CIPHER_MISMATCH"

What does that mean? Am I doing something wrong? Can I access the site by doing something on my end? If yes to that last one, please forget the first two. Many thanks. :) Anna Frodesiak (talk) 11:42, 10 July 2017 (UTC)

All I can say is "it works for me" - Chrome Version 59.0.3071.115 (Official Build) (64-bit), on macOS. Have you upgraded to the latest version of Chrome? Or maybe it's just a temporary fluke - restart the browser (if in Windows, restart the computer) and try again. --Stephan Schulz (talk) 12:32, 10 July 2017 (UTC)

Works for me with Firefox, Chrome, Internet Explorer, and Microsoft Edge. --Guy Macon (talk) 15:15, 10 July 2017 (UTC)

Works for me, too, using Chrome on Windows 7, 64 bit edition. StuRat (talk) 17:45, 10 July 2017 (UTC)

The error message means your browser does not support the TLS/SSL version or cipher being used by the site you're trying to connect to. First off: are you using Windows XP perchance? If so, that's probably why. Windows XP doesn't support some of the newest ciphers and hashes, and it's no longer supported by Microsoft, so it never will. Continuing to use it is very dangerous, because it has unpatched security holes; you need to switch to a supported version of Windows or another operating system. If this isn't the case, the first thing to do is ensure Chrome is updated to the latest version. If you still get this message with the latest Chrome, try a different browser; this will determine whether the issue is Chrome or something else. --47.138.161.183 (talk) 23:27, 10 July 2017 (UTC)

Thank you all. That was very helpful indeed. :) Anna Frodesiak (talk) 07:08, 11 July 2017 (UTC)

So what's the best Windows? Anna Frodesiak (talk) 07:21, 11 July 2017 (UTC)

To overcome this problem you'll need either Windows 7, 8, or 10. I guess most would recommend Windows 10 as it's the latest version and Chrome support for Windows 7 and 8 won't last forever. If you're using XP and don't want to upgrade Windows then it's possible that you could access this site using the Firefox browser. -- zzuuzz ^(talk) 08:34, 11 July 2017 (UTC)

Note that if your computer is now running XP, it becomes increasingly less likely that it supports current versions of Windows - they require increasingly more hardware resources and features of more modern processors. If you are not wedded to particular programs and workflows, you can try to install a lightweight Linux distribution. Last time I was forced to run Windows, I installed XP in a VirtualBox on top of CentOS Linux without any trouble - I suspect this might also work the other way round if you want to play it safe. But mentioning safety: XP has no support anymore, and becomes an easier and easier target for hackers. It's probably a good idea to ditch it as soon as possible... --Stephan Schulz (talk) 08:53, 11 July 2017 (UTC)

Thank you again, folks. I'll get Windows 10 tomorrow (and some new guts if needed). Many thanks! Anna Frodesiak (talk) 09:04, 11 July 2017 (UTC)

I would get a new computer. My neighbor's computer died from a lightning strike last weekend. He was running Windows XP on an old Dell Optiplex. I purchased a new computer off Amazon with Windows 10 and a 4 year warranty for $130. Similarly, I see brand new laptops at WalMart with Windows 10 for under $150. The retail price of Windows 10 Home is $120. Why spend that much when you can replace the computer and get Windows 10 for nearly the same price. 209.149.113.5 (talk) 12:38, 11 July 2017 (UTC)

Good point. The answer is because I'm in China. I'm having trouble just getting Windows 10 now. But thank you. :) Anna Frodesiak (talk) 07:14, 12 July 2017 (UTC)

Zhuangongban is free and has been pushed heavily to every computer by Lenovo, Tencent, Qihoo 360, and Xiaomi, as well as by the government itself. *NOT* upgrading to Zhangongban is the problem people have had. You appear to be the rarity who cannot upgrade. 209.149.113.5 (talk) 18:05, 12 July 2017 (UTC)

Hmmmm, I'm not sure I want a modified Win 10. And does this mean a Win 10 shipped from the West will not work in a China-made PC? Anna Frodesiak (talk) 18:45, 12 July 2017 (UTC)

Windows 10 is not authorized in China. Zhuangongban is the authorized version of Windows 10. Microsoft released it for free and worked with multiple organizations to push it for free to everyone. At the time, China had, by far, the highest rate of pirated Windows PCs in the world. Those "free" Windows installs were laden with back doors, viruses, bots, etc... Microsoft decided that the best thing for everyone was to get everyone on an official Windows OS, not a pirated one. So, you *can* install Windows 10 from Microsoft and then install CJK support. You might have issues with the firewall. Some people who are running Windows 10 (non-Zhuangongban) have said that they have great difficulty accessing websites. Others have said there is no problem and those who say so are just trying to start a controversy. It is up to you. If you want to get pirated Windows 10, it is your fault. If you want to pay a high premium for Windows 10, you can and it may work. If you want to get Windows 10 for free, Zhuangongban is free. 209.149.113.5 (talk) 20:00, 12 July 2017 (UTC)

.apk(s)

What (or which) is the best tested 'phone booster', 'junk cleaner', 'trash cleaner', 'cache cleaner', 'clip board content cleaner', 'temporary Internet file cleaner' 'auto app killer' available?

Could you refer me to something(s) good please?

Note: DU Speed Booster cleans something when you "Uninstall" an app. I want that in an app(s) too please.

103.67.158.10 (talk) 18:26, 10 July 2017 (UTC)

The best "Auto-app killer" is none at all. Unless you have very unusual needs, you should not be running one these programs. They're a scam. They make your phone run slower and use more battery.[3]

As for "Cache cleaners", you don't actually need one. One is built into the OS. You can go to "Settings/Storage/Internal Storage" and tap on cache to delete all cached data from all apps. (Of course, next time you run those apps, they may be a bit slower, because they need to re-download or regenerate the data from those caches.) However for this sort of thing, I personally tend to use App Mgr III, because I happen to like the user interface. It doesn't really do anything you couldn't do with just the OS.

ApLundell (talk) 20:53, 10 July 2017 (UTC)

Amazon Kindle screen saver

I brought an Amazon Kindle and this thing goes into a screen saver after 5 minutes. Why does an E-ink display device need a screensaver for? AFAIK there's no burn-in issue with it. And displaying a static image doesn't take any power for an E-ink device. Covfefe beans (talk) 22:52, 10 July 2017 (UTC)

There could be a privacy issue, if you don't want everybody knowing what scandalous reading material you prefer. :-) StuRat (talk) 03:14, 11 July 2017 (UTC)

I think it's more of a sleep/standby screen than a screensaver per se. I.E. It indicates to the user that the device in in sleep/standby mode and will not respond to touch until you've woken it up. Other people seem to agree [4] [5] [6] [7] [8] If you have a Kindle without touch, I think these devices still function differently when in sleep/standby mode but I admit I'm not certain. With ad supported Kindle devicies, it's also a way to display ads. If you have a sleep cover (I mean a proper one with a magnet to wake the device up), you should barely see the sleep screen. Nil Einne (talk) 07:16, 11 July 2017 (UTC)

July 11

Recovering lost iTunes

Back in aught-11, I had iTunes on my Windows 7 PC and several hundred dollars worth of music in its library. That was all lost some time later, when the machine died with no backup of the tunes. I now have a new computer running Windows 10. It has never had iTunes installed. Is it possible to install iTunes and get my music back without paying for it again? Surely they still have records of the purchases on my account - (?) TIA. ―Mandruss ☎ 10:42, 11 July 2017 (UTC)

Provided that you know the account name and password, you can re-download it. See instructions here - X201 (talk) 11:11, 11 July 2017 (UTC)

@X201: It took hours to get back to the forgotten account name and password, but the rest was easier. I ended up doing it differently from those instructions, but thanks for getting me past the initial hurdle of "Can this even be done?". (I'm surprised Apple would be so reasonable about it, actually.) Awesome to have my music back at a cost of US$0. ―Mandruss ☎ 15:47, 11 July 2017 (UTC)

In my experience, being reasonable about anything but the original price is Apple's business model...you buy a comparatively pain-free life with the premium price. Or in my case, I buy a Unix-that-simply-works on quite good hardware... --Stephan Schulz (talk) 16:20, 11 July 2017 (UTC)

But assuming the OP means they actually bought the music from Apple in the library (as opposed to adding it via the iTunes Matching service) this is hardly something anything close to unique to Apple. It's the whole point of tying your purchases to an account, and it works the same for Google Play, Amazon and pretty much anyone offering music purchases in that way.

The primary problem is whether you can trust the provider not to disappear, and whether the music is DRM free. (Notably, if the music is not DRM free and the provider dies, you're pretty much SOL.) For purchased music thanks in part to Apple's power over the music companies pretty much everyone has moved to DRM free for music purchased from the service.

Videos (TV series, films etc) still have DRM on most services. Still other than the DRM niggle, the basic principle works the same for video (Amazon, Play, Microsoft, Sony, Apple etc) games (Steam, GOG, Humble, Microsoft, Origin, uPlay etc), ebooks (Amazon, Kobo, B&N, Apple, Play etc) etc, albeit with a possibile limitation how many devices may simultaneously use the purchase in sorm form. You don't need to keep a backup of the content locally, you can always retrive it via the service using your account. Again that's the point of the account system or really the "cloud computing" revolution.

Of course the limitations imposed by the system when combined with DRM are controversial hence why e.g. the Xbox One plans failed.

And actually Apple, does impose the limitation that you pretty much have to use their software to retrieve the content (but for music, because it's DRM free not to play it); something fairly common but which isn't always required. Amazon notably still lets you download music via the web. Still for most people the complications of being in multiple ecosystems is too annoying hence why they tend to stick with one and get annoyed when someone tries to force them to adopt another one (e.g. uPlay and Origin) regardless of whether software, limitations etc from the new ecosystems are really any worse than what they were using.

The iTunes matching service is a bit of a different beast although again the Google and Amazon services work similar albeit each with their own limitations etc. The nature of such systems means they're a little more complicated to compare.

Nil Einne (talk) 04:50, 12 July 2017 (UTC)

July 12

hacking the web

Hi, I've heard that it's easy enough to set up a realistic looking, but fake website, eg. for phishing scams (like www.accounts.bank as a fake version of www.bank.accounts). But if everyone else had the correct web address already, could the scam work then? That is, if everyone already knew it had to be the second version, www.bank.accounts, could you still trick people? What would it take to accomplish some such feat? It would seem to involve getting into the web server, or someone's computer, and directly posting your fake information there.

My interest is in whether someone could fake a university degree register, such as http://webapps2.murdoch.edu.au/gradregister/, eg. to pretend you had a PhD in molecular biology, even when the correct address was known by the receiver. I'm curious because I often need to verify my academic degree, eg. for work in China, and I'm wondering if this is technically a secure option (although not legit for China at the moment). IBE (talk) 21:50, 12 July 2017 (UTC)

The problem is that the person who creates the fake web site also provides it's address in an email, etc., and people find it easier to just click on the link than to go look up the address on their own. I imagine some app could run in the background to detect when fake web sites are given, and warn the recipient. Something like: "Warning: This web site is NOT associated with the official Murdoch.edu website, and this may well be a phishing scam.". StuRat (talk) 22:02, 12 July 2017 (UTC)

Yes, but what if that could be avoided? I mean, suppose simply for the sake of argument they did not click on an incorrect address (eg. they have bookmarked the correct address). Can the correct address still be hacked? IBE (talk) 00:59, 13 July 2017 (UTC)

Yes, but that's no longer phishing. There's a table that maps URLs to actual I/P addresses, and that table could be hacked to redirect everyone to a fake site. See Domain Name System. StuRat (talk) 04:35, 13 July 2017 (UTC)

Further, those requests go through the local internet connection. That can alter the name resolution. For example, if you are your local coffee shop, using their free internet access, you are at their mercy when you type "somewebsite.com". They could easily direct you to a fake server. It isn't just them either. Because the network is open to all local users, I could monitor network traffic, see the requests going out, and push my own responses back on the network. If my computer is fast enough, you will get the IP address I want you to have instead of the one you expect. Yes, the proper response will show up right after my response, but computers are not programmed to wait to see if a second response shows up. So, it will be ignored and you won't get any warning of any kind. 209.149.113.5 (talk) 14:05, 13 July 2017 (UTC)

That is why you should use HTTPS for all critical web accesses. HTTPS will check the certificate of the site you connect to, and in particular check if the certificate has been issued for the address in question. Certificates are handed out by certification authorities who are (hopefully) reliable. --Stephan Schulz (talk) 14:22, 13 July 2017 (UTC)

Correct, but untrusted DNS is still a problem. Scenario: You go to https://mybank.com. I hijack your DNS and send you to my server. My server supplied you with a page that looks just like mybank.com, but it isn't. My server also sends you an SSL certificate. Your browser looks up the IP address of the authority for the certificate. Again, that points to my server. So, my server does the authority exchange and tells your browser that the certificate is valid, go ahead and sign in. There is a lot of ways that this whole process could fail, but it could also work. If I ran it at a hotel, I would have hundreds of potential people to trick into giving me their credentials. 209.149.113.5 (talk) 14:44, 13 July 2017 (UTC)

Untrusted DNS is a versatile attack surface, but certificates are not usually (or, IIRC, ever) verified online. Rather, they are signed by another CA and so on, up to a list of root CAs, and their public keys are embedded in the browser and/or the operating system. --Stephan Schulz (talk) 15:11, 13 July 2017 (UTC)

Correct, but there is a connection made to the authority to validate the certificate (at least the first time it is encountered). To really get into how untrusted DNS can be hell, you need to look at another practice: Fake certificate authorities. It is becoming increasingly common for organizations to run fake certificate authorities so they can perform deep packet inspection of SSL/TLS traffic. The web browser doesn't inherently trust the fake authority, so a warning is shown. The user accepts the authority and, then, the certificate authorized by the authority. The users are trained to ignore warnings that the CA is not accepted by the browser. Now, in a hotel on a business trip with their work computer, they go to their bank account, I slip them a fake certificate authorized by my fake CA and they get some sort of security warning that the CA is not automatically accepted by the browser. They click the exception or install or whatever the browser tells them to do and the fake certificate is now a trusted certificate. There are two roots to this problem. First, DNS cannot be trusted. Second, there should only be a handful of certificate authorities, preinstalled on all web browsers, and companies should have the option of creating fake ones so they can spy on their employees. But, that is just my IT security rant. If I was a business manager, I'd likely have a different point of view. 209.149.113.5 (talk) 15:22, 13 July 2017 (UTC)

July 13

Excel

Formulas:

	A	B	C
1	3	formula in $C$1, where ★=A1	=2^★
2	4	formula in $C$1, where ★=A2
3	5	formula in $C$1, where ★=A3

Result:

	A	B	C
1	3	8	=2^★
2	4	16
3	5	32

Is there a way to do this? --Loroon (talk) 01:31, 13 July 2017 (UTC)

Just to make sure I understand, you want to a way to define Bn=2^An, right ? Do they have a way to define a formula on columns, as opposed to cells, to give us B=2^A ? StuRat (talk) 01:36, 13 July 2017 (UTC)

My $C$1 is an incredibly lengthy formula whose value is defined by a specific other value. These other values shall be listed in Column A, in no particular order. Then, I want every cell in Column B to refer to the 'template' formula in $C$1, so as to avoid typing that lengthy formula in every single cell in Column B. --Loroon (talk) 01:50, 13 July 2017 (UTC)

OK, so my description was correct, except that you want talk about it in general terms, so Bn = f(An), rather than the Bn = 2^An example ? StuRat (talk) 04:32, 13 July 2017 (UTC)

Yes. So how to do it? --Loroon (talk) 07:26, 13 July 2017 (UTC)

You could create a custom function in VB, it takes minimal coding experience, there are plenty of online guides. If you can do complex formulas you'll be able to do it. - X201 (talk) 07:42, 13 July 2017 (UTC) - X201 (talk) 07:42, 13 July 2017 (UTC)

It probably takes minimal coding experience, but I have none at all, and have no idea where to start. Could you show me what to do exactly? --Loroon (talk) 11:14, 13 July 2017 (UTC)

You probably don't realise this, as you say "to avoid typing that lengthy formula in every single cell in Column B" - but if you create the formula in cell B1, and copy and paste it to the other cells in column B, the formula is automatically adjusted to point to the cell in column A that you want it to. So there's no need to do a lot of typing - just type it once and copy and paste it. Phil Holmes (talk) 15:13, 13 July 2017 (UTC)

I'm aware of that, sorry for using the wrong term. The problem is that it's a list of several thousand values already, and will be growing. So good ol' copy-pasting the formula or dragging it down results in a massive file size, so I'm looking for ways around this. And by the way, the template formula in fact contains more than one parameter (there are also ☎, ♜, ☕), but I guess I'll easily figure out how to do them all once you teach me how to do just ★. --Loroon (talk) 16:20, 13 July 2017 (UTC)

Youtube comments

How do you put a paragraph break in Youtube comments? Because I've written a yuge comment regarding military strategy in a possible war with North Korea, and tried to break it up into several paragraphs, but Youtube just keeps collapsing it into one humongous paragraph which is well-nigh unreadable! 2601:646:8E01:7E0B:0:0:0:CDF0 (talk) 05:30, 13 July 2017 (UTC)

I've encountered this problem before, where they strip out the blank lines and return characters. I suggest multiple posts, one for each paragraph. The only other option is using some character they won't strip out, like a bunch of periods, to create a separation between paragraphs. That will look ugly, but at least should be more readable. Some type of a numbered list also helps with the problem of the person recalling where they stopped reading, if they don't read it all at once. StuRat (talk) 13:07, 13 July 2017 (UTC)

Thanks for the bad news! So the only solution is either to break it up into multiple posts, or else fill out the line with periods when starting a new paragraph? 2601:646:8E01:7E0B:0:0:0:CDF0 (talk) 00:15, 14 July 2017 (UTC)

Anyone who reads comments frequently will see that there are a lot that just stop in mid-sentence. Looks like YT may be taking steps to stop the tactics suggested here. Akld guy (talk) 11:04, 14 July 2017 (UTC)

Where does

'My Saves' folder of Google sit, e.g., in my mobile ? (I can see my saved pics only by 'view saved'). Is it on a 'cloud', accessible from any device ? בנצי (talk) 06:22, 13 July 2017 (UTC)

Compass app

Could you refer me to a good and reliable compass that doesn't require internet or GPS and all other on-line connectivity rubbish. I wish to use it off-line. Also, without the hassle of calibration issue please. 116.58.205.146 (talk) 16:19, 13 July 2017 (UTC)

Is this OK? Ruslik_Zero 20:36, 13 July 2017 (UTC)

When buying a physical compass, you must be aware of compass balancing. Compass#Compass_balancing_.28magnetic_dip.29110.22.20.252 (talk) 23:42, 13 July 2017 (UTC)

On the line alternative to MS Access

I am buying a new computer and although I could probably port my MS Office license, I aim to jump to Google Docs to replace MS Word and Google Sheets to replace MS Excel. What can I use to replace MS Access?

["On the line" is a reference to a joke in The Best Exotic Marigold Hotel.] Hayttom (talk) 19:05, 13 July 2017 (UTC)

Google does not have an application similar to MS Access. So, you will need a third party application like here. Ruslik_Zero 20:34, 13 July 2017 (UTC)

July 14

Word Press Form Generating Emails

Hi All

I am not a developer, but I have a paid a dev team to build a Word Press site for me, but I'm having issues with a form that they have created.

Newsletter Subscription: Enter email address field, two check boxes, submit button

In the Word Press backend, there is a special mailing list field, where I enter the email address where the list of new subscribers should be sent - currently set to "optin@xxxxx.com

When a website visitor completes the newsletter form, an email is generated from & to the optin@xxxxx.com with the visitor receiving a notification that they have subscribed.

During testing and before I had set up the proper email addresses for the site, I was just using my personal email xxxxx@gmail.com as the address for the newsletter in the backend, and this worked fine, but what I found astonishing was that not only did I receive an email in my gmail inbox advising of a new subscriber, but the generated email was also listed in my gmail SENT items!

How can this be possible, surely this is open to massive abuse, as a form could be created to make threats etc. and then it would look like an innocent person had sent it - and the proof of sending would be in their sent items!

Please be aware there is no feature in the back-end where I enter my gmail password and in fact I have 2-step verification set anyway.

I was discussing this with a friend tonight and he couldn't believe it was possible, and to prove it, I entered one of HIS email addresses from his website in my Word Press backend for the subscribers list, and he was amazed to see that the form had generated an email that appeared both in the inbox AND sent items of his email account.

Before anyone asks, I don't know how they have done it, but if someone can advise me where to look in the backend, I will happily advise further.

The reason I am posting this, is that I don't see how this activity is legal, and surely it is a massive bug/security hole - as there are huge implications for email privacy.

Maybe I have got this wrong, and this is something that people are aware of, but I have never heard of someone being able to generate an email and have it placed in the sent items of an account without having the correct login credentials.

I certainly would feel extremely uncomfortable, if I checked my sent items and saw emails relating to illegal activity - and of course the first thing I would do would be to change my password, which would have no effect, as the password seemingly is not required to generate these emails via a form!

Can anyone advise about this, as I don't want to have a problematic form/code on my site, and I just want some more information before I go back to the developers and complain about it Jaseywasey (talk) 00:03, 14 July 2017 (UTC)

---

• From what I've interpreted, you've done email spoofing. Did you use Reply-to: or To:? The latter may appear in the "sent" email box with some clients, even if it was delivered somewhere else than the To: address listed. 2001:2003:54FA:D2:0:0:0:1 (talk) 10:09, 14 July 2017 (UTC)

DVI or VGA

A DVI-I to VGA adapter

• A normal PC built in 2017
• Windows 10
• A normal flat-screen TV
• A normal, say, 3GB MP4 movie playing on VLC

If the connector/wire from the PC to the TV is DVI, will the movie play better than if it were coming through a VGA connector?

And if the connector at the back of the computer is DVI, and an adapter (pictured) is used, how would that change things?

Many thanks. Anna Frodesiak (talk) 02:41, 14 July 2017 (UTC)

Second question

Should the man who installed the new motherboard with DVI notice that the old motherboard had a VGA socket and not let you go all the way home only to discover that your monitor plug won't fit into the back of the computer? If yes, what word would appropriately describe that man? Anna Frodesiak (talk) 02:45, 14 July 2017 (UTC)

Poor salesman. He should have sold you a new monitor as well.196.213.35.146 (talk) 07:20, 14 July 2017 (UTC)

Is there a way to see the unique amount of plays of a youtube video?

Is there a way to see the unique amount of plays of a youtube video?

Just as some example, some people use youtube to listen to music, and so the amount of IPs and/or users that watched a video will be way smaller than the amount of plays the page will show, this because people will watch the same video more than once, because they will listen the same song more than once.177.92.128.26 (talk) 11:33, 14 July 2017 (UTC)