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September 4

USB keyboard not recognised by boot CD? Would PS/2 be different?

I made a bootable USB disk version of "Hiren's Boot CD" and it is recognised by the BIOS and appears in the list of drives. The problem is that it doesn't respond to my USB keyboard. I'm wondering whether it's reasonable to think that it would respond to a PS/2 keyboard instead. The BIOS responds to my USB keyboard so I figure there's no reason that the "boot CD" shouldn't either? If the BIOS doesn't need any drivers to talk to the keyboard then neither should the boot CD, right? In which case I'd have to conclude that the boot CD hangs after loading. --145.255.246.8 (talk) 00:23, 4 September 2017 (UTC)

There's a fair chance a PS/2 keyboard would work, but if I were you I'd make sure to turn on any legacy USB keyboard etc options in the BIOS before worrying about that. You shouldn't assume the keyboard working in BIOS will mean it will work on other OSes. If it's actually EFI not BIOS, your assumption about a lack of drivers isn't even necessarily correct. Nil Einne (talk) 04:51, 4 September 2017 (UTC)

If you have enabled any legacy USB support etc in the BIOS, see [1] for some more suggestions. Based on that, I'd try a cold boot and also disconnecting any unneeded peripherals if enabling legacy USB isn't enough. Nil Einne (talk) 14:16, 4 September 2017 (UTC)

To add to the above excellent advice, if you are going to be mucking about with systems that have PS/2 ports, it might be worthwhile to just keep a PS/2 keyboard on hand. $17.75 on Amazon.[2] a PS/2 mouse will cost you another $6.25.[3] I was fixing an old Dell a while back, and found that it worked great with a USB mouse and keyboard, no drivers needed, in Linux and Windows, but I could not change the BIOS settings without a PS/2 keyboard. --Guy Macon (talk) 21:20, 4 September 2017 (UTC)

Note: The 5 volts needs to be present on the jack, anyway if PS/2 or USB. When using USB, the internal USB bridge and USB hub need to be supported by the operating system. Do not use and USB3.x for HID devices like mouse and keyboard when USB2.x or lower are present. Some M/Bs have a combined PS/2 and two USB jacks in one printed connector. Use this ports first. Check BIOS for "USB legacy support" option. Toggle this setting. A dual mode HID comes with an passive USB-PS/2 adapter. Just 4 wires an a shield connection installed. See articles. There is no specification, how to adapt the CLK and DATA from PS/2 to USB D+ and D-. Same chip designers most likely use identical adapters, no matter if green or violet. --Hans Haase (有问题吗) 12:59, 5 September 2017 (UTC)

Video info update during sharing

Resolved

When one renames one's own YouTube video, there appears to be some delay in its info update when sharing through Facebook. While on YT itself the info updates almost instantly, I waited for about one day and when clicked to share through Facebook, the popup sharing window still displays the old title and description. What to do and how long does it take? 212.180.235.46 (talk) 07:13, 4 September 2017 (UTC)

Edit the message on facebook, and if that doesn't work remove it and post it again. I don't think FB is going to check if the name of a YT video has changed. (((The Quixotic Potato))) (talk) 07:41, 4 September 2017 (UTC)

Turns out it's just in the preview of the popup sharing window and after sharing, the updated title is shown correctly. 212.180.235.46 (talk) 09:42, 4 September 2017 (UTC)

Good source of free Mellotron samples?

I'm looking for a comprehensive database of digitized Mellotron samples, especially from the M300 series. I've checked out a lot of sites but it seems that they're always in some weird proprietary format (and in any case, the listings are generally very sparse). Can't seem to locate much of anything in a standard container (wav, mp3, webm, etc). 73.232.241.1 (talk) 11:24, 4 September 2017 (UTC)

Not really free but definitely good if you can ignore the noise of someone singing. Blooteuth (talk) 13:38, 5 September 2017 (UTC)

Yeah, I love those old videos! What I'm really wanting to do though is write a program that allows you to play/record songs using samples taken from an actual machine. 73.232.241.1 (talk) 20:47, 5 September 2017 (UTC)

Good luck with your worthy project. The Mellotron's reported polyphonic aftertouch will be a challenge. Blooteuth (talk) 22:09, 5 September 2017 (UTC)

Yeah I was thinking about that. No straightforward way to emulate it with a computer keyboard (too bad they don't detect pressure). I was wondering if some clever combination/interpretation of key presses might do the trick, but so far haven't come up with any good ideas for that just yet... 73.232.241.1 (talk) 22:33, 5 September 2017 (UTC)

What's this? Or am I missing something? --jpgordon^{𝄢𝄆 𝄐𝄇} 22:11, 5 September 2017 (UTC)

God love you man, thanks so much! That's exactly what I was looking for. 73.232.241.1 (talk) 22:33, 5 September 2017 (UTC)

Happy to help. That was just the first Google result searching for "mellotron samples". --jpgordon^{𝄢𝄆 𝄐𝄇} 23:49, 5 September 2017 (UTC)

I don't generally like to use Google (just on principle) but I have to admit that I may be getting the short end of the stick in search results because of that. I might need to reconsider my choice there...73.232.241.1 (talk) 23:57, 5 September 2017 (UTC)

Well I can't say what it was before this question, but it's also currently the first search term for Bing and DuckGoGo. Nil Einne (talk) 15:31, 6 September 2017 (UTC)

September 5

Tape drives as named pipes

In the days when tape drives were secondary rather than tertiary storage, did any of them have separate read and write heads and allow the read head to run a few thousand bytes behind the write head, thus serving as named pipes with the additional benefit of backing up the most recently-read few thousand bytes (assuming the computers they were connected to allowed block-level access)? NeonMerlin 01:28, 5 September 2017 (UTC)

I couldn't find anything in Tanenbaum. Regardless, it's unclear how this would work or what it would accomplish. There may exist tons of (anonymous) pipes and FIFOs at any moment in the system. Their semantics don't require them to be seekable, either (in fact, even in modern Linux, they aren't.) Whatever buffering there is, as I understand it, is solely in order to accommodate atomic writes to the pipe but there's always the option to suspend the write()ing process until someone reads from the pipe. 80.171.95.62 (talk) 05:04, 6 September 2017 (UTC)

September 6

Is Moore's Law still alive for memories?

It seems that Moore's Law for microprocessors has been dead for years, although it might be resurrected by a new way forward like nanotubes, blahblah. But is it still true that memories are still getting bigger, cheaper, and faster?

Yes. --jpgordon^{𝄢𝄆 𝄐𝄇} 03:04, 6 September 2017 (UTC)

Yes, Moore's law is true for memory, no, it is absolutely not true that "Moore's Law for microprocessors has been dead for years". As our article on Moore's law says:

"In April 2016, Intel CEO Brian Krzanich stated that 'In my 34 years in the semiconductor industry, I have witnessed the advertised death of Moore’s Law no less than four times. As we progress from 14 nanometer technology to 10 nanometer and plan for 7 nanometer and 5 nanometer and even beyond, our plans are proof that Moore’s Law is alive and well'. In January 2017, he declared that 'I've heard the death of Moore's law more times than anything else in my career ... And I'm here today to really show you and tell you that Moore's Law is alive and well and flourishing.' ".

Read this: "Moore's prediction still has plenty of life in it. Here's why." --Guy Macon (talk) 05:31, 6 September 2017 (UTC)

github / latex question

Hello. I am learning to use github and want to use it to manage my Master's thesis, which is written in LaTeX. Right now I am working on the referees' comments and have two PDF documents, and in addition I also have two hardcopy versions of the thesis, which have handwritten annotations and corrections. What is best practice for this situation? I want to have some system for verifying to myself (and indeed my supervisor) that I have indeed accounted for any given comment, whether on the PDF or hardcopy. Can anyone advise? Robinh (talk) 05:01, 6 September 2017 (UTC)

There's a track changes package [4] that you can use to flag places where you've corrected, then easily turn off those annotations for pretty printing. Really, you should ask them to comment in your source code, they may object, but any prof should be able handle opening a *(^#$(*#^ text file and editing it ;)

I suppose if you make a github commit for every single correction you made, then you can show them that list of commits, each of which has a short summary of what you fixed. Then you or they can check the diffs and see exactly how each bit was handled. But that seems even more likely to meet with resistance. SemanticMantis (talk) 15:56, 6 September 2017 (UTC)

(OP) Thanks for this, SM. The topic is on the extreme soft end of the hard-soft spectrum, so I can't assume that anyone will even know what a text file actually is, much less edit it. My main concern is somehow linking the hardcopy annotations to the github commits. My best idea so far is to tag each commit with a comment like "thesis 1, p23a" (in addition to the usual commit text), which will peg the commit to the hardcopy; and then to write on the hardcopy "sorted on 2017-09-07" so I can verify that the comment has been attended to. And I am unsure how to deal with the PDF files. But does anyone have any better ideas? Robinh (talk) 18:58, 6 September 2017 (UTC)

A good way to annotate a LateX-created PDF is via the todonotes package. So you could transfer all annotations from all copies into todonotes in the same PDF, and remove them or mark them as resolved as you work through the list. It is a bit painful (since for each issue, you read it, you add it in the todonotes in a commit, you solve it, you remove the todonote), but that should make the reviewers happy.

The usual way to deal with a cycle of multiple atomic (review - feedback - fix) groups in the tech industry is via some sort of bug tracking system. Github has such a system called issues, which allows to make issues close when you put some magic words in the commit comment. It would probably be easier to convince your reviewers to click on "new issue" and fill in a description in a relatively user-friendly way than either of SemanticMantis' options. Or you could fill in the issues yourself, naming them something like "draftN pageX paragraphY: reviewername: short description" (putting any details in the body) so that they can easily follow it. It has the advantage to keep track of closed issues after they are solved, but that works only if your reviewers are willing to use the github issue tracking, which may be a long shot. Tigraan^{Click here to contact me} 12:10, 7 September 2017 (UTC)

Todonotes looks nice, but I fail to see how it's much different than the trackchanges package: they both use LaTeX markup to annotate the PDF, and both will require OP to manually transfer handwritten comments to the source code, both can flag issues and mark them as resolved. It's maybe a little more streamlined for solo usage, and less options for multi-author collaboration, so I think I'll try it out, thanks. I do agree that git "issues" are probably much better than my ignorant suggestion of using commits. SemanticMantis (talk) 15:41, 7 September 2017 (UTC)

Huh, trackchanges does seem like a clone of todonotes (or the other way around). I failed to parse your first comment, or I would have acknowledged that, sorry.

Also, using commits with well-formed commit messages comment might actually be better than a bug tracking system (just pick a template message that makes the commit log searchable). The latter would be the Correct Way To Do It™ in an ideal world, because you can solve multiple issues in one commit, reopen issues etc. but in a world where the OP has to transfer all feedback to it because reviewers won't fill them directly in GitHub, I am not so sure. Tigraan^{Click here to contact me} 16:10, 7 September 2017 (UTC)

(OP) Thanks guys, I appreciate your guidance here. I have just looked at github issues and this is pretty much perfect for me. I can go through the comments, create as many issues as appropriate, then pick them off one by one. One reason I'm doing the revisions this way is to learn github, so this ticks a lot of boxes for me. Best wishes, Robinh (talk) 20:13, 7 September 2017 (UTC)

Resolved

Stopwatch and a Timer

Separate or both together please…something with lots of intervals… 103.67.158.224 (talk) 08:51, 6 September 2017 (UTC)

Your question is not clear. (((The Quixotic Potato))) (talk) 13:46, 6 September 2017 (UTC)

You haven't asked a question. If you are looking for a stopwatch with a countdown timer, most stopwatches have that function. Just Google "stopwatch with countdown" and you will find plenty. --Shantavira|^{feed me} 16:23, 6 September 2017 (UTC)

Are you looking for a program with these functions ? If so, on what device and operating system ? Android ? Windows ? Apple ? StuRat (talk) 22:04, 6 September 2017 (UTC)

Windows and Android platform. Something good and reliable please. 103.67.158.154 (talk) 17:07, 7 September 2017 (UTC)

PHP/MYSQL Login code

I wrote login script myself The login pages script is cas1.php as follows:

cas1.php

<html><body><h2>Please login to make requisition for Printer Paper & Cartridge</h2> <h3>Your requisition will be attended ASAP</h3> <h3>In case there is delay beyond 3 days please make fresh requisition</h3> <b>Enter your UserName:<b> <input required type="username" name="username" minlength="5" maxlength="15"> <br><p> <b>Enter your password:</b><input required type="password" name="password" maxlength="15" minlength="5"> <br>` <input type="submit" value="Login"> </form></div><div><form method="POST" action="http://localhost/pwchanger.php"><b>Please click if you have forgotten password:</b><input type="submit" value="Reset"></form></div></html>` The formhandling page for logging in is takinguserinput.php as follows `<?php $dsn = "mysql:dbname=userdetails;host=localhost;port=3306"; $username2 = ""; $password2 = ""; $con5=new PDO($dsn, $username2, $password2); $con5->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $con5->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);$x13=$_POST['username'];$x12=$_POST['password'];$hashsalt=password_hash($x12,PASSWORD_DEFAULT); $con5->beginTransaction(); $stmt7=$con5->prepare("SELECT `password` FROM `user_data` WHERE `username`=:username"); $stmt7->bindValue(':username',$x13); $stmt7->execute();$x9=$stmt7->fetch(PDO::FETCH_ASSOC);echo $x9; if(password_verify($x9,$hashsalt)&& isset($_POST['Login'])){ session_start();echo "iamhereproperlyloggedin"; } else { $con5->rollBack(); $stmt7=NULL; $con5=NULL; die('You are not allowed'); } ?>`

But instead of logging in and taking me to file "takinguserinput.php" i am always getting you are not allowed using the only user i have created username Admin and password welcome whether username password correct or not .Please help me to make the code workable103.24.109.98 (talk) 10:24, 6 September 2017 (UTC)

I have edited your comment a little bit. (((The Quixotic Potato))) (talk) 13:48, 6 September 2017 (UTC)

Your input fields are not INSIDE your form. The submission from the form should be one file. The handler for the submission should be another file. You can do it in one file, but it won't look anything at all like what you are trying to do. You apparently need to learn a lot more about HTML before getting into this or you wouldn't be placing your input fields outside your form. Then, when you understand HTML, you need to work on the difference between client code and server code. 209.149.113.5 (talk) 17:07, 6 September 2017 (UTC)

Using industrial plug in standard UK socket

I recently bought a second-hand vacuum cleaner; when it arrived it turned out to have a plug that looked like this [5] and says on it: "110V 16A-4H Typ P 216-4 S"

I would like to use this in my home which has regular UK 3-pin plug sockets. Is there an adapter I can get that will do this? What should I look for? A lot of them seem to say 'PAT testing only' whatever that means? Thanks! Amisom (talk) 17:27, 6 September 2017 (UTC)

Your buy may not have been such a bargain. The problem is not the plug, but the voltage. You have a 110V cleaner and your home (presumably UK) will be on regular UK 230V, with regular UK plugs and sockets.

Converters are easily available and may be seen on any building site. However they're not just a plug adapter, they're an autotransformer to change the voltage (and also the earthing). [6] As a result, they're not cheap. Andy Dingley (talk) 17:54, 6 September 2017 (UTC)

Advertise it on eBay. You may very well get back what you paid for it -if not more :-) P.S. State: Buyer Collects; as postmen find vacuum cleaners difficult to get through the average letterbox. Aspro (talk) 18:44, 6 September 2017 (UTC)

If you're wondering why anyone in the UK is using 110v - it's a very common practice on building sites, as Andy says. [7][8]. -- Finlay McWalter··–·Talk 20:33, 6 September 2017 (UTC)

<Joke that'd probably be very dangerous to take seriously> Buy another identical one and wire the two of them in series </joke> 92.40.248.207 (talk) 21:20, 6 September 2017 (UTC)

Voltage mismatch isn't the only problem either, it's the frequency - UK systems use a lower one than the US, so there is also a chance that the motor doesn't spin-up properly. Your money might be better spent on a vacuum designed to operate off of local mains...73.232.241.1 (talk) 04:00, 7 September 2017 (UTC)

Much smaller problem. Most appliances handle 50 Hz or 60 Hz just fine. It's the voltage that is the problem. --Guy Macon (talk) 05:50, 7 September 2017 (UTC)

Hmm, I guess not. It looks like only a few types of devices are really affected by it (such as induction motors, although these aren't typically used for things like vacuum cleaners apparently) so it likely wouldn't be an issue for the OP in this case. 73.232.241.1 (talk) 07:26, 7 September 2017 (UTC)

For the last part of your question, see PAT Test.--Shantavira|^{feed me} 08:47, 7 September 2017 (UTC)

A domestic step-down transformer is available on e-bay. This is different from the building-site version. Your PAT test converter would be extremely dangerous to use because it doesn't change the voltage. Expect an explosion if you try it! Dbfirs 11:14, 7 September 2017 (UTC)

Note that a US spec step-down transformer is not generally usable here. It's OK for working US equipment (although the build quality of many is borderline lethal) and also that the use of US plugs and sockets in the UK isn't legally permissible outside "testing" in an electrical workshop (UK rules don't consider US plugs to be safe for voltages over 50V). However this device here is presumably UK market construction site equipment, and expects the UK centre-earthed 110V supply. There may be an issue with whether this cleaner would be adequately earthed if used on a US-style conversion transformer and sockets. You would certainly need to PAT test it before use. You might also find house insurance etc. being an issue - there are plenty of cases where UK house insurance failed to pay out after a fire caused by poor quality US-spec electrical equipment, or badly made Chinese equipment, and the insurers are getting very tight on this issue at present, as the number of fires is increasing. Andy Dingley (talk) 11:29, 7 September 2017 (UTC)

Yes, Andy makes a good point. I think your vacuum cleaner is designed for a building site or industrial application with 55v each side of earth (110v split phase), not the American market. I withdraw my above suggestion. Dbfirs 11:43, 7 September 2017 (UTC)

I don't withdraw my suggestion though. Sell it on eBay. The OP may have been in the right place at the right time to purchase an industrial vacuum cleaner that someone else might want and will be wiling to pay the current value for it – which may be more than the OP paid. If he gets offered a bit less, then he has cut his loss a little bit but not suffer a big total loss on the whole transaction. Aspro (talk) 20:17, 7 September 2017 (UTC)

September 7

Stupid censorship question

For the past few weeks I've been following the troubles of Daily Stormer, which has been repeatedly denied basic DNS service. What I don't understand is that each time it actually has a DNS address, you can just "nslookup a dailystormer.whatever" and get some location like 198.251.90.113, which is a typical IP address that has a typical whois with some random company official who can and presumably is being hit with the typical tide of complaints, DDOS attacks, death threats etc. until the last quixotic believer in freedom of expression is purged from the internet. So the part I don't get is why do I keep reading about the attacks on the DNS servers and cave-ins by their maintainers and not attacks on the actual IP addresses of the magazine? Wnt (talk) 02:26, 7 September 2017 (UTC)

Respondent appears to have admitted their comment had zero to do with the topic Nil Einne (talk) 14:57, 9 September 2017 (UTC)

If it's a read-only site, there's not much you can do to it directly. On the other hand, if they sell things or allow comments, then a Denial of Service attack is possible. (A DoS is technically possible with a read-only site, but they won't lose revenue from it, so can just wait until it ends.) StuRat (talk) 02:48, 7 September 2017 (UTC) I don't understand the relevance of 'read only' here. A site which is trying to make money will lose revenue from a DDoSed regardless of whether it's read only. A site which isn't trying to make money is not going to lose revenue if it's DDoSed regardless of whether it's read only. Even when a site is nominally not read only it isn't uncommon the non 'read only' part of it is mostly irrelevant. For example it's possible the NYT, CNN, Fox News, the WSJ and the Washington Post allow comments or other user interactions but the importance of these pale in comparison to the read only parts. When people DDoS them they are almost universally trying to stop people seeing the 'read only' parts and may not care at all about the non 'read only' parts. Also your response doesn't seem to answerthe question namely why target the DNS server rather than the webserver. Nil Einne (talk) 07:16, 7 September 2017 (UTC) It may be that StuRat is under the impression that you cannot DoS a "read-only" site. Which is wrong, since "reading" (i.e. getting the HTML page) involves a query of the server (see Transmission Control Protocol and HTTP). It may be that the POST attack could not work on "read-only" sites but I do not know if it is feasible (and if it is, whether it is common practice) to deny all POST requests for such domains. TigraanClick here to contact me 08:21, 7 September 2017 (UTC) Except that StuRat said "A DoS is technically possible with a read-only site, but they won't lose revenue from it, so can just wait until it ends" so they seemed to know it was possible to DDoS (or at least DoS) a read only site. This is of course often all you can do with a DDoS, wait it out read only or not. I mean okay there are mitigation measures, but most of them don't relate to whether or not your site is read only and they don't tend to work that well if the DDoS is powerful enough beyond simply having a CDN capable of surviving the DDoS which is one thing which by and large works whether or not your site is read only or not. The only real difference I can think of is that since the CDN probably isn't providing the back end elements to support the non read only elements, it's possible that a DDoS could over whelm these, but most CDNs dedicated to protecting from DDoS, like CloudFare, tend to have various measures to try and prevent that from happening. Of course if the DDoS is in the form of a spam attack on these non read only elements, you will need to counter that, but this form of attack isn't very common. About the POST vs GET point, I'm fairly sure quite a lot of DDoS actually rely on on some form of amplification, e.g. DNS amplification so the actual traffic received by the target isn't even something it's expecting or necessarily understands. [9] [10] [11] [12] [13]. I'm not sure however what the attacks relating to DailyStormer did. Nil Einne (talk) 09:17, 7 September 2017 (UTC) My point was that an organization dependent on revenue from their web site could be forced out of business by repeated DoS attacks, while one which only uses their web site to provide info can afford to just wait it out. StuRat (talk) 14:27, 7 September 2017 (UTC) But this has zero to do with whether a site is read only, and for that matter whether the site only provides info. As I said, many sites which are read only only and incidentally only provide info are reliant on their websites for the revenue. Maybe the examples I have weren't the best since many of them are also offline news souces but there are websites which are solely commercial online news sources. (There's of course also the cross counter of sites which often don't make much revenue directly but still are a very important part of the revenue stream. Microsoft for example, although they do have their webstores and subscriptions nowadays these are likely still a minor part of their revenue. Yet both now, and when these were less important, stuff such as the knowledge base and MSDN were often very important to their revenue stream despite only providing info and other data, and being often read only and not the sort of thing they want down even for a day. Not to mention updates tend to come basically from a website.) Meanwhile forums are not read only (unless they're archives) and some of them don't rely on revenue. Some forums do ask for donations (others have premium memberships etc which are more directly selling you a product, have ads etc), but not all do as some are just pet projects or whatever of the owner (often donations etc only come into it when they get too big). And incidentally it seems that the Daily Stormer was at times asking for donations too [14]. (Frankly I'm not really sure where donations fit into your limited world view. Donations are of course a funny thing, many people here think the WMF get way too many of them, and while they do have their campaigns, not all of them directly come from those campaigns but from direct approaches with large donors. Yet whatever people may think of the way the WMF spends their money, wikipedia is surely a key part of why they get those donations, even in those instances where they come direct from large donors and are there's an agreement to direct them at something else.) And funnily enough, I've confirmed while researching this your claim about read only isn't even correct. Daily Stormer did have a BBS which they used for comments on stories, for example. You did mention revenue, as you do now, but you keep also making incorrect points about 'read only' and 'info only' which makes it sounds like you're someone from an out of contact tribe in Africa or South America who has never actually used the internet and have no idea how it works, and doesn't work since I imagine basically everyone else here, knows that a site being 'info only' or 'read only' doesn't mean they don't make revenue from it, and that a site being not 'read only' doesn't mean they do. You seem to be trying to make a point about sites like Amazon and other sites which directly sell you products but ignored the fact that many, many sites are not like that, but still are either the only or a very important part of a companies revenue stream and not something they can really simply afford to leave down. Google and Facebook are of course a famous example where people keep saying including here on the RD that you are the product because most of their money doesn't come from direct sales to the end user. Although as I said, if you aren't a massive company or have one behind you, whatever your business model if any you often have limited choice but to wait out a DDoS. Since while there are mitigation measures most of which have little to do with whether your site is read only or info only, they can't generally completely counter most types of dedicated DDoS. In fact whether or not you're a commercial enterprise where your website is an important part of your enterprise or an advocacy or misinformation campaign, doesn't necessarily affect the availability of mitigation measures except that a commercial enterprise may be more likely to be able to afford them, or more desperate too. But then again, there are a lot of very rich donors out there. And so for example, very near the end of an election campaign, there's a good chance for some sites which are basically read only info only advocacy or misinformation sites have a lot more money and desire to keep them up, than August D'Angelo's business selling home made cat hats even if that's the only way they sell them. (In case it's not obvious, this is a made up example.) I'd add that something like CloudFare isn't that expensive and even free for some [15] [16]. While they did cut off DailyStormer, they have said they're generally very reluctant to do so regardless of how controversial the site is. And provided your actual usage fits the plan you subscribed to, I'm not sure how much they care that you're a big target unless perhaps you're specifically doing things to encourage it (as opposed to just doing things which annoy people), although obviously the less you pay the less sophistication and support etc you get. And incidentally, since Amazon came up, there are sites like ToysRUs and Walmart for example, where the sites are both used for direct sales and for info for their retail stores a bit like Microsoft except with sales via the website being more important. Yet despite Amazon basically being nearly completely reliant on their website (and app etc which likely rely on the same components), they could actually probably better afford to have their website down for a few days despite the massive disruption and loss of revenue because of how big they are compared to some other smaller retail stores where the website is also an important part of their revenue stream (so probably not ToysRUs Or Walmart). Of course good luck DDoSing Amazon, Microsoft, Google, Facebook but the points stands. In other words, your comment didn't actually make your point. It said something else. And it wasn't even that good a point since while it's true whether or not a site is making revenue partly reflects whether or not they can afford to wait it out, it's not the only measure by far. Nil Einne (talk) 06:30, 8 September 2017 (UTC) You misrepresent me as having made claims about what type of web site The Daily Stormer has/had. I made no such claims. And, of course, there's a continuum from a company 100% dependent on their web site for revenue and those 0% dependent. Those with web stores, and no brick-and-mortar stores, will likely be closer to 100% and those without, closer to 0% (there are always exceptions, of course, such as revenue from ads). So, back to my point that a company highly dependent on it's web site for revenue can be put out of business by cyber attacks, while one that is less dependent can wait it out. StuRat (talk) 16:12, 8 September 2017 (UTC) My main point was you said completely stupid things which you did any anyone can see that. If it's a read-only site, there's not much you can do to it directly. On the other hand, if they sell things or allow comments, then a Denial of Service attack is possible. (A DoS is technically possible with a read-only site, but they won't lose revenue from it, so can just wait until it ends. }. Let me repeat for the last time, whether a site is read only or not or whether they allow comments or not, has nothing to do with whether they can be DDoSed, nor whether they can survive being DDoSed. And let me repeat, the claim that Daily Stormer is read only is simply not true anyway. They do allow comments. So this comment was wrong in every single way, and therefore completely irrelevant. If you're admitting that your comment had zero to do with the questions since you weren't talking about Daily Stormer but making random general comments, I might as well collapse this discussion. Don't blame me for assuming that sicne you were replying to Wnt you were actually trying to help rather than making random general comments which had nothing to do with the website in question. My point was that an organization dependent on revenue from their web site could be forced out of business by repeated DoS attacks, while one which only uses their web site to provide info can afford to just wait it out. As I've made clear, an organisation can be entirely dependent on revenue from their site despite it being "info only". It's true an organisation depend on revenue from their website could be forced out of business by a DDoS, that's a non sequer and also irrelevant. Nil Einne (talk) 14:57, 9 September 2017 (UTC)

Are you sure only their DNS servers were DDoSed? For example, DreamHost was one of the targets [17] and while some of the sources confirm their DNS servers appeared to be affected it's not clear to me their web servers weren't. In any case, many of their recent hosts seem to have been like DreamHost and provided both DNS and web hosting. CloudFare also provided both DNS and CDN [18]. So ultimately whether you target their DNS hosting or web hosting or both you have the same company targeted. Their current host is definitely new [19] [20] [21]. I'm not sure if their current host provided DNS hosting but it's not like finding DNS hosting has been the issue anyway. The problem is they keep losing their domains, for reasons nothing to do with DNS hosting. Nil Einne (talk) 07:59, 7 September 2017 (UTC)

P.S. I've perhaps oversimplified the difference between the CDN component and the reverse proxy component of something like CloudFare, although despite the pointless diversion above about read only sites, I'm not sure if it's that important in the context of this question. Nil Einne (talk) 05:57, 8 September 2017 (UTC)

@Wnt: See https://imgs.xkcd.com/comics/free_speech.png and https://blog.cloudflare.com/why-we-terminated-daily-stormer/ (((The Quixotic Potato))) (talk) 08:07, 7 September 2017 (UTC)

Also, if the site has simple text-only pages, as opposed to many pics and, even worse, videos, it won't take much data transfer to load the page, so you would need a lot more page requests to cause a DoS. If they have some simple protections, like not allowing more than one page load request from an IP per second, this should help. StuRat (talk) 14:38, 7 September 2017 (UTC)

Except as I already mentioned before your reply, many DDoS don't rely on requests the site even understands. They may use DNS amplification or other forms of amplification to simply flood the site with traffic. Do you have some statistics on how many DDoS actually rely on HTTP Flood or otherwise requests to generate responses from the target site? I've looked and couldn't really find any. I can find stuff like [22] which has general statistics, but it's hard to say from them how much of a component they are. Because there are various mitigation measures, which can significantly reduce the effects depending on the sophistication of the attacker and defender [23], I'm not sure how common these are nowadays compared to other types of attacks except perhaps when you know they will work (e.g. because whoever set up the site isn't very good) or there's limited alternative (e.g. possibly attacks to Tor sites). Although I'm pretty sure this type of thing is also very clustery. Someone figures out a method of attack that works well, and everyone uses it until it stops working, perhaps because enough people fix their services that it no longer works. HTTP Floods are to one extent something where that doesn't apply however as just mentioned, actually generating and countering them is an arms race including the source of the attacks [24] [25] Nil Einne (talk) 06:30, 8 September 2017 (UTC)

You can also perform DDOS attacks s l o w l y.[26] A Quest For Knowledge (talk) 16:36, 8 September 2017 (UTC)

I remain confused. I should note however that the nslookup still goes to the same IP address as yesterday. Going to the IP address gets a "domain not in our systems" message from BitMitigate. Going to dailystormer.at gets to a continually-reloading page. If scripts from dailystormer.at and bitmitigate are enabled (I hope I didn't catch anything...) this will currently crank for a bit and display the Daily Stormer site. (Note that Tor not only can display the same site without scripts, but despite media unanimity to the contrary seems to do it faster, at least if you don't count the 30-second wait when you first start the Tor browser before you can type the address) Now I have to admit that obviously BitMitigate is doing something very clever and fancy whose understanding is the difference between typing on Wikipedia and being the CEO of a tech company. But I don't get how the people listed in the whois for the IP address, and the machines that reach them, have managed to hold out against hostile hordes. Wnt (talk) 17:58, 8 September 2017 (UTC)

A url for producing the raw text of a random featured article?

Hello,

For a machine learning project I need a url that would produce the raw text of a random featured article in Wikipedia as a .txt file. By raw text I mean only the article itself (not the entire html page) and with square brackets for internal links etc. Preferably I want an option to specify the language as well. Does something like that exist?

For example - the following link produces the raw text of a random article (not featured article) in Hebrew Wikipedia: https://he.wikipedia.org/wiki/Special:Random?action=raw

Thanks! — Preceding unsigned comment added by 77.127.95.225 (talk) 08:17, 7 September 2017 (UTC)

• I am not aware of such a URL, but is that really necessary? If all you want is for the program to pick out a random article, you can do the randomness yourself.

Featured articles are listed at Wikipedia:Featured articles. I suggest you parse the latter page to generate a list of the page titles of featured articles, pick out a random item from the list by your own program's pseudorandom generator, and pull that article via the API. (I imagine you could host a web server that gives a request URL that redirects to a random FA by this process, though I fail to see the point.)

If you intend many queries (as seems to be the case in "machine learning project"), please see mw:API:Etiquette before starting. Tigraan^{Click here to contact me} 08:36, 7 September 2017 (UTC)

Thanks for your answer. I Just thought this approcah would be faster. Could you direct me to instructions specifying how do I get the raw source code text of an article via the API (I'm working in Python)? — Preceding unsigned comment added by 77.127.95.225 (talk) 09:13, 7 September 2017 (UTC)

With http://tools.wmflabs.org/erwin85/randomarticle.php I produced this link to get a random article in Category:Featured articles: https://tools.wmflabs.org/erwin85/randomarticle.php?lang=en&family=wikipedia&categories=Featured%20articles&namespaces=-1. Category:Featured articles (Q4387444) shows the category name for featured articles in many languages. PrimeHunter (talk) 10:41, 7 September 2017 (UTC)

Well, PrimeHunter's solution looks good if you can extract the code from the page it redirects you to. But in case you need to work with the API in Python...

It is probably better-coded elsewhere, but you can take inspiration / copy-paste from this (I encourage you to pull the user-agent identification snippet as well, and populate it with your own info). Using api_call with parameters {'foo1': 'bar1','foo2': 'bar2',...} in a Python dict will request the URL en.wikipedia.org/w/api.php?foo1=bar1&foo2=bar2&.... Then see mw:API:Revisions with action=raw.

This produces stuff such as [27]. Is that the format you are looking for? Tigraan^{Click here to contact me} 15:59, 7 September 2017 (UTC)

You could do it as a two-stage process. Go to https://en.wikipedia.org/wiki/Special:RandomInCategory/Featured_articles figure out the url that you were redirected to, and suffix it with "action=raw".

ApLundell (talk) 17:01, 7 September 2017 (UTC)

Excel Formula sought

I have columns with titles “Unit(s)”, “Costs” and “Unit(s) bought”, “Unit(s) left”, “Spent”, “Leftover”. I filled “Unit(s)” and “Costs” column manually and “Leftover” column automatically (integrated with "Spent" column), now formulas are required for the “Unit(s) left” and “Spent” columns so that every time I insert number(s) in the “Unit(s) bought” column, auto result displays on both… Could you help me please? 103.67.156.84 (talk) 17:11, 7 September 2017 (UTC)

To make sure that we have understood what you need, could you give an example with numbers, and are we correct in assuming that the columns are A to F (and that there are no hidden columns)? Dbfirs 18:48, 7 September 2017 (UTC)

Column A: Unit – pre-set data available here.

Column B: Costs – pre-set data available here.

Column C: Units bought – data will be inserted here.

Column D: Spent – require a formula that understands column “A”, “B”, “C”.

Column E: Units left: require a formula that understands column “A”, “B”, “C” and “D”.

Column F: Leftover: require a formula that understands column “A”, “B”, “C” “D” and “E”.

::Note:

I’ve used ‘minus’ sign on column “E” and “F”. Formula looked something like:

A–C for column “E”, and

B–D for column “F”.

What I wish for is, to insert value in column “D” so that “E” and “F” are displayed automatically.

116.58.200.14 (talk) 14:58, 9 September 2017 (UTC)

Recovering pendrive’s datas

When you recover a pendrive’s datas, what do you recover?:

1) only the last inserted files and folders.

2) everything since the beginning of time.

103.67.156.84 (talk) 17:11, 7 September 2017 (UTC)

Same as most drives. Everything since the start, so long as it hasn't been overwritten since. This is why, when doing any recovery work, it's important to not write anything new to the drive (such as downloading the recovery software to it) while you're working on it. Andy Dingley (talk) 17:46, 7 September 2017 (UTC)

Free advice: back up your data multiple places so that the next time you don't have to do any data recovery. --Guy Macon (talk) 06:23, 8 September 2017 (UTC)

While data recovery from USB flash drives is often like from magnetic hard drives, I have found this isn't always the case. USB flash drives don't generally support TRIM but they do generally have some sort of wear leveling implemented on the controller, and precisely how this interacts with deletion seems to vary, even if the data isn't actually zeroed or nominally overwritten I have found odd behaviour. That said, all you can do with try, although even more so than hard disks, I would recommend imaging rather than dealing directly with the USB flash drive, and maybe even keep a copy of the image to reduce the possibility of screw ups (although realistically most recovery software doesn't even have the option to write). And imaging ASAP even, if the device is plugged in, even if not mounted so you think nothing should should happen. I do agree with Guy Macon that the best solution to data recovery is to never actually need it. Nil Einne (talk) 10:12, 8 September 2017 (UTC)

"Data" is the plural, not "datas". "Datum" is the (rarely used in this context) singular. StuRat (talk) 16:52, 8 September 2017 (UTC)

I understand the part of overwriting files, what about folders? A file will be inserted or kept in a folder, should I overwrite a folder(s), or a file(s)? And what do you mean by "Everything since the start, so long as it hasn't been overwritten since." Let me give you an example for a better understanding for myself:

Today is the first day I bought a pendrive and used it, inserted file name "A", "B", "C", kept it for few days then deleted them all. After deletion, I inserted file name "D", "E", "F", kept it for few days then deleted them all. Will I still possess the trace of "A", "B", "C"? If yes then I'll overwrite...

How long will it take to recover data from a 16GB USB Flash drive/pendrive? Someone will give me something but desires my absence for 20-30 minutes…

The speed it takes will depend on the speed of the pen drive and what you're trying to recover. As I said above, you really should image the whole thing before doing anything in which case the time taken will at a minimum be how long it takes to read the whole drive. Also no matter a hard disk or with a USB flash drive, whether or not something will be overwritten depends entirely on the OS (or whatever is writing) and file system. Trying to predict whether it has happened is generally pointless, instead just image the drive and try to recover. A for the directory vs file point, well you're getting into the additional issue that even if the data hasn't been overwritten, the file system references may have been. More sophisticated recovery software can look for signatures for various known file types and try and recover them even if the file system reference is gone, but whether that will work, will depend again on too many things to give a general answer like how fragmented the drive was (since USB devices are still presented to the system as simple block devices), the size of the file, the type of the file, precisely what has been written where etc. Nil Einne (talk) 14:44, 9 September 2017 (UTC)

I've no idea on how to do imaging data. Could you give me a 'step by step guide' please, on how to imaging files and folders please? 103.67.156.6 (talk) 15:02, 9 September 2017 (UTC)

September 8

Miro Converter

Does anyone know the link to get it? I want to upload a video for the lizard article. The download thingy at http://www.getmiro.org/ doesn't work for me. Thanks. Anna Frodesiak (talk) 09:27, 8 September 2017 (UTC)

There must be 50 million sofware capable of outputting WebM with VP9 and Opus, is there some particular reason you need to use Miro Converter? Nil Einne (talk) 10:21, 8 September 2017 (UTC)

I just remember Wikimedia recommending Miro. Could you recommend another freebie that does the same thing? Cheers. Anna Frodesiak (talk) 10:47, 8 September 2017 (UTC)

Facebook Videos Pausing When Window Loses Focus

I'm not sure when this started happening, but this morning I noticed that I start playing a video in my Facebook feed and the window loses focus, the video automatically pauses. I'm using Firefox on Windows 10. Does anyone know how to keep the video playing so I can multitask? A Quest For Knowledge (talk) 11:09, 8 September 2017 (UTC)

From my experience, Facebook has been doing this for a long time, but it mostly happens with videos on main Facebook page (even if you full screen the video, actually possibly worse if you do that), especially those which are autoplaying. If you actually open the video and click on play, it's normally fine. Nil Einne (talk) 06:25, 9 September 2017 (UTC)

“.bs7” file type

I wish to turn this file type into an animated wallpaper. What step should I take? 103.67.156.29 (talk) 17:44, 8 September 2017 (UTC)

First, you need to get Windows 7 Boot Updater to pull the animation out of the file. Then, you can save the animation in a format that is functional for wallpaper. 209.149.113.5 (talk) 19:05, 8 September 2017 (UTC)

Keyboard

I’m planning to buy keyboards (small and extended) which consist of the “Delete” button ‘right next to’ the “Left arrow” key. Could you display the type and design name, for both please? 103.67.156.29 (talk) 17:44, 8 September 2017 (UTC)

Sounds like a compact keyboard, made to be portable, such as for laptops. StuRat (talk) 14:35, 9 September 2017 (UTC)

If they consist of a Delete button and a Left Arrow key, they sound like very compact keyboards indeed. Though quite ample for the purposes of some of my less favorite colleagues on Wikipedia. ;) Wnt (talk) 14:54, 9 September 2017 (UTC)

September 9

Mutation testing to extract minimal example of a bug?

I have a project which uses Checker Framework, and which in at least 13 places has to use the @AssumeAssertion technique where castNonNull should theoretically be sufficient but actually raises an error message. These cases are almost certainly bugs in Checker Framework. But I can't report them, because the Checker Framework devs say that in situ they're too complicated, and I don't have time to manually reduce each of them to its simplest form in a different branch of my project. (The last time I tried to do that, it took me a whole day to handle just one case, and I was still told the 76-line result was on the overly-complex side.) Can automation help with this problem? I'm thinking of a variant of Mutation testing in which all the mutations are simplifications, they are applied cumulatively to reach the frontier of simplest examples, and the meanings of success and failure are inverted compared to the usual application of mutation testing (in that we start with a failing test case and perform every possible simplification that will leave it still failing). NeonMerlin 00:38, 9 September 2017 (UTC)

Pascal: Number <=> String

How can I convert a number to a string and vice versa? — Preceding unsigned comment added by 129.45.127.64 (talk) 13:47, 9 September 2017 (UTC)

That will depend on the language. What language are you using ? StuRat (talk) 14:16, 9 September 2017 (UTC)