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March 4

steamOS problem

Hi. I am trying to install steamOS. I have downloaded SteamOSInstaller.zip. I am having difficulty with step 2:

Unzip the SteamOS.zip file to a blank, FAT32-formatted USB stick.  Make sure to use an MBR partition.

I am not sure what this means. I am using a ubuntu linux machine and type

cd /media/USBDISK/
unzip ~/Downloads/SteamOSInstaller.zip.

(the USB stick is formatted FAT32). Then when I insert the USB stick into the target computer and boot from the USB stick, it says "An operating system wasn't found". I know I'm missing something obvious; can anyone advise? Robinh (talk) 06:53, 4 March 2017 (UTC)

First quick thing to check: if the computer's BIOS has a "secure boot" setting, switch it from "Windows UEFI" to "Any OS". 91.155.195.247 (talk) 12:45, 4 March 2017 (UTC)

Also, check to make sure the computer will boot from a USB stick without you explicitly telling it to in the BIOS settings (I've been stung by that one before). If you have access to another computer, you could also try boot it with your USB stick, which will give some indication of where the actual issue is. Finally, if you didn't format the stick yourself, you may need to do that and explicitly make it bootable (MBR stands for Master Boot Record, which is the address that your computer expects to find the actual boot code; if it's not there, the computer won't boot). OldTimeNESter (talk) 17:29, 4 March 2017 (UTC)

(edit conflict)Have you checked that the OS did actually unzip to the USB stick? Did you copy SteamOSInstaller.zip to the USB before issuing the command? There are two suggested methods here. Dbfirs 17:34, 4 March 2017 (UTC)

The MBR bit part of the intructions is critical. It's not enough to copy the files on the USB stick and expect that the computer will find and boot from them. That's way you get the message about an OS not being found. Here you can find one way of making the USB stick bootable: [1]

You also have to pick the right settings to allow the computer to boot from alternative media (which are not your HDD). Somehow it's easier to boot from a CD than from a USB stick. Hofhof (talk) 18:29, 4 March 2017 (UTC)

Agreed, but the SteamOSInstaller, when run, after being unzipped, should create the boot sector, rather than needing extra software. Dbfirs 19:49, 4 March 2017 (UTC)

Disagree. To run the SteamOS Installer you'll first have to create a bootable USB stick and put it there. --Hofhof (talk) 22:55, 4 March 2017 (UTC)

(OP). thanks everyone! I am 100% certain that the computer is booting from the USB stick (I can boot my knoppix USB no problems). I have made the USB stick bootable as per advice from Hofhof. Dbfirs says "the SteamOSInstaller, when run, after being unzipped, should create the boot sector". How do I do this? How to run SteamOSInstaller? Robinh (talk) 20:53, 4 March 2017 (UTC)

Since the USB stick is bootable, now unzip the files in it and try to boot from it. You will be prompted by the installer about what to do next. "Automated install (WILL ERASE DISK!)" is the easiest choice. I am following the instructions here

But be careful: this is not like a live USB/CD (like Knoppix) that won't even mount your HDD unless explicitly told to do so. It's also not an install CD (like Debian, Ubuntu) where you can choose a partition of your HDD to install to. This will weep the whole HDD.Hofhof (talk) 22:55, 4 March 2017 (UTC)

I have had some success with USB-based operating systems that don't boot by doing the following:

1. Install Tiny Core Linux to the USB stick from the coreplus image at[2] (use frugal and vfat options).
2. Confirm that TCL boots.
3. Install the new OS, overwriting TCL.

Why does this sometimes work? My theory is that the new OS somehow gets confused about how to make the USB stick bootable and does nothing, leaving a tiny part of TCL on the stick even though you told it to overwrite everything. --Guy Macon (talk) 02:40, 5 March 2017 (UTC)

(OP) OK, everything failed except for Guy Macon's suggestion. I have managed to boot Tiny Core Linux from the USB. I downloaded an ISO file, then used unetbootin to make the USB bootable. This worked! I have a working version of Tiny Linux. I then unzipped SteamOSInstaller.zip on the USB stick, thinking that this would make the USB stick boot into SteamOS. But it boots into Tiny Core Linux. Guy, can you talk me through "Install the new OS, overwriting TCL" (or, better, point me to a FAQ) please? Robinh (talk) 06:00, 5 March 2017 (UTC)

It is clear that simply unzipping the contents of SteamOSInstaller.zip on the USB did nothing to overwrite Tiny Core Linux, and thus that following the instructions never actually got a SteamOS Installer program to run. Yet that is what the instructions at http://store.steampowered.com/steamos/buildyourown say to do! As we speak I am downloading SteamOSInstaller.zip, but I am on a slow connection and it will take a while.

There are a bunch of places where you can find instructions for installing SteamOS.[3][4][5][6][7] Some give the same "unzip the files and it will boot" advice that isn't working for you, but some talk about making a bootable CD or DVD from an ISO. I would try that next.

BTW, I always disconnect power and data from all of my PC's hard drives before trying to install any new OS, whether installing to a USB stick or to a scratch hard drive I keep around for just this purpose. --Guy Macon (talk) 14:30, 5 March 2017 (UTC)

(OP) thank you Guy. It is good to know that you too are interpreting the instructions the same way as me. I have seen most of the links you point to; as you say, they all give the "unzip the files and it will boot" line. Which is, as you say, not going to work. I didn't realise that there were ISO versions of steamOS out there. I'll download one of those, use unetbootin to make the USB bootable, and have another go. Best wishes, Robinh (talk) 18:53, 5 March 2017 (UTC)

I finished downloading SteamOSInstaller.zip and unzipped it into a separate folder. I see several readme files, a setup.exe and an autorun.inf that runs the setup.exe. I am not willing to go to my windows box and try to run that setup.exe, but looking at it with a text editor I see the telltale string "This program cannot be run in DOS mode", so it is a windows program. Got an old, hard drive floating around? Disconnect the drives you care about, plug in the old drive and install whatever version of Windows you have handy on it (formatting with FAT, not NTFS), unzip SteamOSInstaller.zip to a folder, and run setup.exe. If that fails repeat but unzipping to the root. If you succeed, be sure to follow up hetre so the next peson will know what does and does not work. --Guy Macon (talk) 21:00, 5 March 2017 (UTC)

Google Chrome tab icons vs. labels

Google Chrome uses helpful mini-icons to label each tab. For example, there's the distinctive Wikipedia W mini-icon. However, when I open too many tabs, it switches over to truncated text labels, such as Wiki for Wikipedia. I don't like these at all, as they are easy to confuse, such as with Wikinews, Wikihow, etc. So, is there a way to prevent it from making this switch ? I realize that the mini-icons would also need to be truncated, but that's better than truncated text. I also realize there are workarounds like having multiple browser windows open, each with a smaller number of tabs, but I'd prefer a better solution. StuRat (talk) 17:44, 4 March 2017 (UTC)

You can't without an add-on. If you have a lot of related tabs, look for a tree tab extension. 71.85.51.150 (talk) 01:48, 5 March 2017 (UTC)

Web Browser Blocking Access to the Clipboard

I use Firefox, and recently I've received notifications from several websites that my web browser is blocking access to the clipboard. These usually appear as a pop-up message and advise me to use the keyboard shortcuts instead. First, why do the keyboard shortcuts work at all if the browser is blocking access to the clipboard? Second, this only happens on some websites: for example, on Amazon, I can right-click and Paste directly from the clipboard without any problems, so clearly the browser isn't blocking access to the clipboard unilaterally. Why does it work on Amazon, but not on certain other websites? OldTimeNESter (talk) 23:02, 4 March 2017 (UTC)

The popups mean to say: Firefox doesn't allow websites to directly access your clipboard (bypassing you) through a javascript. This is for security and privacy. See [8].

It's fine, websites should never be allowed access to resources on your computer, because your computer is yours and not theirs. You may have data on the clipboard and it's not up to them to decide that your data can be overwritten. And surely it's not up to them to read whatever you have on your clipboard.

You yourself can of course access the clipboard through keyboard and mouse, that's never blocked by your browser. That's also fine, because your clipboard is on your computer, so you're the boss.

Decent websites, apparently including amazon, don't even dare to touch your clipboard and have no reason to produce such a popup.

Summarized: some websites have nasty habits, and your browser is protecting you from that.

There may be ways to make the clipboard accessible to scripts (see the above provided link), but I would strongly recommend against that. You're not missing any functionality, except that you have to copy and paste manually. That's probably what you'd expect anyway.

Hm, I used too much text, but I hope this helps anyway. :) Jahoe (talk) 03:35, 5 March 2017 (UTC)

For an example of why this might be a problem, imagine you did a screen grab during an online purchase, and had your credit card info on it. StuRat (talk) 05:40, 5 March 2017 (UTC)

...or that your lovely but somewhat naive teenage daughter copy/pasted her latest sexy selfie... (Yes, the clipboard can contain images.)

Many people don't realize that, after copying, the data remains on the clipboard until they use it again. And Windows provides no direct way to clear it. Jahoe (talk) 13:20, 5 March 2017 (UTC)

Clip something else, that won't get you into trouble. StuRat (talk) 15:45, 5 March 2017 (UTC)

OP here: thanks for the clarification. The odd thing, though, is that I can't access the clipboard with the mouse, just with the keyboard shortcuts. For example, lets say that I copy some text from a website, and want to paste it in an e-mail. My e-mail program won't let me right-click and select Paste; instead, it gives me a popup that says "you need to use the keyboard shortcuts", which do in fact work. I've visited other websites that behave the same way, but then there are sites like Amazon that let me right-click and select Paste. So I guess my question should have been "Why can I access the clipboard using only the keyboard shortcuts?" OldTimeNESter (talk) 15:38, 5 March 2017 (UTC)

@OldTimeNESter: I think you're under the impression that websites can predict what you're going to do – and I feel I need to clarify you overestimate them: they can't. They can not know in advance you're going to paste anything. Please note they do not say 'You can not paste with your mouse". They actually don't care about pasting at all! They're rather protecting their own contents from being copied by you. Also, probably, from being directly printed or reverse-engineered, because those functions (Copy, Print, View Source...) are usually available from a context-menu.
You may want to verify in the browser's main menu whether corresponding commands get disabled (greyed) when you visit one of sites you mentioned. --CiaPan (talk) 23:12, 6 March 2017 (UTC)

• I know a lot of people who store passwords in a text file and copy and paste them (not that I'm condoning this). I know a lot of people who occasionally copy and paste passwords under other circumstances, too. Also credit card numbers, usernames, etc etc. There's also a huge cross section between those folks and folks who leave browser pages open for hours on end. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 17:53, 6 March 2017 (UTC)

March 6

XHR (Javascript): Absence of webpage necesses asyncasy?

Data items requested directly from the backend does require webpage bootstrapping...

In contrast, data items requested with XHRO as in AJAX (or AJAJ, to be more modern) are returned without bootstrapping of the webpage.

My question is this: Why excactly does the first way is synchronic and the second is asynchronic (by means of how the requested data items will return), I mean, why does the ABSENCE OF BOOTSTRAPPING necesses asyncasy?

78.48.189.23 (talk) 03:38, 6 March 2017 (UTC)

I take it "necesses asyncasy" means "requires asynchronicity", but what is "bootstrapping"? This Bootstrap? Asmrulz (talk) 02:14, 7 March 2017 (UTC)

Bootstrapping === Reloading of the webpage. Ben-Yeudith (talk) 04:00, 7 March 2017 (UTC)

In that case, the whole purpose of asynchronous requests is to fetch additional data without reloading of the page. Asmrulz (talk) 09:39, 7 March 2017 (UTC)

Asynchronous just means non-blocking, that is, the request returns immediately, and when the data is ready, a user-supplied callback function is called. And there can be any number of them running at a given time. They could've made background requests blocking, but that would be bad for the user. Asmrulz (talk) 09:39, 7 March 2017 (UTC)

Yes user:Asmrulz, but it seems to me, as a humble student, that you can load data synchronously as well, without bootstrapping, as it will just be loaded in an order, so I miss why is there a "necessity" for asyncasy if we pass the bootstrapping... Ben-Yeudith (talk) 11:46, 7 March 2017 (UTC)

are you the OP? dfq is asyncasy? about the only ghit for asyncasy is this page Asmrulz (talk) 13:35, 7 March 2017 (UTC)

Yes. BY "Ayncasy" I mean to getting the data asynchronously. Ben-Yeudith (talk) 15:13, 7 March 2017 (UTC)

oh, ok. Sorry. I just thought I sensed sarcasm. Anyway, there is no need, per se, and you can, if you must, send synchronous requests. One reason to use the blocking version is if you need to make sure the request completes before the user leaves the page or closes the browser. However, asynchronous requests are preferable, because they don't freeze the browser so much (the javascript engine apparently runs in the main UI thread and doesn't "come up for air" (i.e., let other code run) if it's inside XMLHttpRequest.send().) Plus, as I said, you can have many of them, because you don't have to wait for each one to complete before instantiating another one. Also see asynchronous I/O, it doesn't talk specifically of the web stuff, but the same principles apply. Note you don't need asynchronous I/O if the language (or the runtime environment in general) has threads. You just put a potentially time-consuming function in a separate thread and wait for it to finish. But there's no mechanism for this in Javascript and even if there were, asynchronous functions are still neater. Asmrulz (talk) 17:58, 7 March 2017 (UTC)

This answer helped me so much! I thank you very much Asmrulz! Ben-Yeudith (talk) 19:16, 7 March 2017 (UTC)

Time delay after failed login

What do you call the time delay after a failed login? It's what websites and other things require to make a brute-force attack take a long time to be successful. 208.95.51.38 (talk) 17:35, 6 March 2017 (UTC)

To the best of my knowledge, there's no official or industry standard name for the practice. Google doesn't seem to contradict me on this, though an editor with a specialty in security might be able to provide an answer. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 17:50, 6 March 2017 (UTC)

I think the technical term would be a "backoff algorithm," as in the exponential backoff algorithm or the randomized backoff algorithm. Applications of this technique - enforcement of a delay before permitting a retry - exist in the context of software security, but also exist in network theory and communications theory at large. For example, if you study ethernet in great technical detail, you will learn about Carrier sense multiple access with collision detection. A well-informed student will read a few case-studies about voluntary- and mandatory- enforcement of delayed retries: there is a tradeoff between best-case, worst-case, and median-case performance. The very same analysis can apply to these delays: whether they are emplaced to prevent accidental- or intentional (malicious) retry attempts; or, whether the retry applies to a very-low-level communication protocol like ethernet or a very-high-level software protocol like application-layer authentication.

To provide a little bit more concrete example of the tradeoffs: a system that enforces very strict back-off delays after failed attempts may be very robust against a brute force attack but is pathologically susceptible to a denial of service attack.

Nimur (talk) 18:12, 6 March 2017 (UTC)

That is why I don't volunteer for doing any security-related coding tasks at work. I set up a log-in that (among other things, including an IP blacklisting function) enforced a 5 second delay as part of a school exercise, and found that a single machine with a slightly clever IP spoofing set-up could effectively lock my site up indefinitely. I thought I was being clever, but it turned out to be just another reminder that Dunning-Kruger make no exceptions. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 18:59, 6 March 2017 (UTC)

All implementations that I've worked with base the delay on the user account, not the client. You try to login as "alice" and fail, it gets a 1 second delay attached to that account regardless of who tries to use it. Fail again and it is 2 seconds, then 4, then 8, then 16, then 32... Once a successful login happens, the delay goes back to zero. Therefore, a distributed attempt will only be useful if the server is highly threaded and you can get multiple login attempts with the same delay value. 209.149.113.5 (talk) 13:23, 7 March 2017 (UTC)

The anecdote I related was a school project. I thought it would be clever to stop a computer from trying the same password (such as password123) with multiple accounts. Again, the punchline is that I made the system highly vulnerable to a DDOS by being clever. The moral of the story was that when it comes to IT security, you shouldn't try to be clever unless you know what you're doing to begin with. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 15:27, 7 March 2017 (UTC)

Because timeouts are used extensively in software development, using the word "timeout" to indicate a time in which a person cannot login seems reasonable. On the programming and database side, I often see it labeled as a timeout variable or a timeout column in the database. I remember it because when I see "timeout", I think of giving a child a timeout and mentally see the computer telling the hacker: You need a timeout. 209.149.113.5 (talk) 20:53, 6 March 2017 (UTC)

I went digging into the source code for a few common modules related to "logging in on the command-line": login, implemented in GNU glibc-2.25 and Apple's BSD layer. I couldn't find any delays or delay enforcement logic!

But I did find pam_fail_delay in libpam for Linux, (and libpam-32.1, an open-source fork distributed with macOS). If you aren't familiar, PAM is the standard that you're probably using every time you authenticate to a Linux or Unix system or even if you build your own open-source Unix system from Apple-distributed source code. This is the software library that does the real hard work of authentication; login itself just plumbs the sessions together.

Surely, if you go digging through the application-layer source code for other common use-cases like the login through your favorite SSH server, you'll find similar separation of concerns.

So if we want to get really technical, for many of the POSIX-ish systems you find in the real world, there's no delay after a failed login. There's a delay after a failed authentication. The distinction is subtle but important - you might be using a computer system where authentication never involves typing on a teletype!

Nimur (talk) 01:49, 7 March 2017 (UTC)

Cellular automata maze generation

As we all know, among the 262144 possible Life-like cellular automaton rules, quite a few produce mazes. Among these, two are particularly well known, and are even named: Maze (B3/S12345) and Mazectric (B3/S1234). These are mentioned every time you talk about CA mazes. (See, for instance, Maze_generation_algorithm#Cellular_automaton_algorithms, [9] and [10]. There are also a few named variants of these, like "Electrified maze" and "Maze with mice".) My question is why these two were originally chosen as examples of maze-generating rules.

What really makes my wonder is the fact that there are -- in my opinion -- better examples of maze-generating Life-like rules, like B2/S123 [in fact, probably every one of these: B2(7)(8)/S(0)123(5)(6)(7)(8)]. As I discuss on my website, both Maze and Mazectric produce extremely disconnected mazes, if you interpret the live cells as the walls. If you interpret the dead cells as the walls, Maze gets a bit better, while Mazectric doesn't improve. Still, even the "improved" Maze is highly disconnected. On the other hand, B2/S123 and her friends produce one huge connected component and only a small number of tiny other components.

Does anyone know the history behind these CAs? In addition, what was the original interpretation of the living/dead cells? Walls or corridors? --Andreas Rejbrand (talk) 20:21, 6 March 2017 (UTC)

How do spammers know when an address is active?

Over the past several years, I've moved between a few institutions, and used respective email addresses to varying degrees. Right now I have three academic email addresses, call them A, B, C. A is new, and I get sciencey spam there on a near daily basis (e.g. "Less bias for your RNA-seq experiments!"). Address C I've had for ~5 years. When it was new and actively used, I got plenty of spam, but now, I almost never use it, and almost never get spam. Account B is in the middle, both by usage and by spam. It certainly seems there is a pattern at play. My question is: how do spammers know that an account is active vs. inactive? I suspect I could be wrong, and I haven't kept careful usage stats, but over time this pattern seems to have become stronger. None of the addresses is posted in any especially prominent place, though all are technically available through institutional directories. I thought I understood the basics of how email worked, and that it ruled out easy ways to see if someone uses an account more or less regularly, but maybe not... Thanks for any insight, SemanticMantis (talk) 20:25, 6 March 2017 (UTC)

What you likely do not see is the levels of spam filters that email goes through before you receive it. For example, GMail does a lot of filtering. Most businesses do some filtering. Even programs, such as Thunderbird, do filtering. Over the years, the filters can change. So, address B may have become more heavily filtered over the years and it is just coincidental that you don't use it much. 209.149.113.5 (talk) 20:45, 6 March 2017 (UTC)

None of these are gmail. I do see at least two levels of filtering, I get "spam control:end user digest" messages from two of the three (B, C). Also I have my apple Mail app shows me the messages it has marked as spam (though of course some spam makes it through both). To clarify: email account C got a LOT of stuff caught in the filter when it was new/active, and now there isn't any even in the filter. I strongly suspect B, C use the same filtering. SemanticMantis (talk) 22:06, 6 March 2017 (UTC)

You may yourself give the information to spammers if you open the spam. There are techniques, known as Email tracking, that allow the sender to know when the message is displayed at the receiver's device – see e.g. Web beacon. --CiaPan (talk) 21:06, 6 March 2017 (UTC)

So that can indicate that my mail.app basically marked the message as "read"? I don't click on any web links anything. Also, the "unused" account is not used to receive or send "real" emails, but the spam that got through the filters was still being clicked on by me, enough to be marked as "read" and perhaps have a 1x1 gif loaded before I can delete. Anyway, this is the best lead yet, so thanks! SemanticMantis (talk) 22:11, 6 March 2017 (UTC)

@SemanticMantis: That's correct – simply opening (displaying) a message is enough. If it's a multimedia message, for example it contains some images embedded, which are not actually included inside the message but rather referenced with an external URL pointing at some web server, then the owner of the referenced site will know when the image is fetched. If they prepare a unique URL for each message, then they know who (which recipient) has opened their message – that is, which recipient e-mail address is active. That's why most e-mail client programs allow blocking externally linked images. And it doesn't need to be a transparent 1-by-1 pixel GIF; it may as well be an image of some device they offer you or their logo or the message background, etc.

Similary the HTML content may refer external definitions, e.g. CSS files, which makes exactly the same possibility of mail tracking. That's why email clients offer rendering just a simple HTML or blocking HTML at all. --CiaPan (talk) 22:53, 6 March 2017 (UTC)

Thunderbird, at least, allows you block remote content, so even if the email has hidden gifs etc., you can safely read the rest of the message. It's a setting under Options -> Privacy -> Allow remote content. CodeTalker (talk) 01:44, 7 March 2017 (UTC)

Yes, that was what I was about to say.--Aspro (talk) 21:09, 6 March 2017 (UTC)

• I don't want to make anyone paranoid, but one of my fellow students worked in the IT department when I was in college, and he was offered money to put spyware on the email server that did nothing but track the creation of new email addresses and (from what I could tell when we played with it instead of installing it) the frequency with which they were used. He was told by the person who made him the offer that it was not malware, just an advertising tool. He refused, but I pretty much guarantee that there's a student out there somewhere who didn't. That being said, I consider that pretty unlikely to be your answer, as it's a lot of risk for not a lot of reward. Just figured I'd throw it out there. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 22:54, 6 March 2017 (UTC)

See Email address harvesting for some of the methods used to get emails. Old emails do tend to go out of use so addresses which have been more recently verified are used preferentially. Dmcq (talk) 23:49, 6 March 2017 (UTC)

March 7

Do browsers use multiple connections in parallel when connecting to a website using HTTPS?

Browsers generally can use multiple parallel HTTP connections to the same website to speed up retrieval. Do they do the same thing when they are using HTTPS? (Multiple connections are more expensive when using HTTPS because of the overhead of TLS handshakes.) --134.242.92.97 (talk) 16:18, 7 March 2017 (UTC)

Surely, but there are some problems with it. Ruslik_Zero 20:02, 7 March 2017 (UTC)

Alert button app

I want a Windows PC app that has the following properties.

• Displays a button that can be pressed with the mouse.
• Stays on top of other windows.
• Makes an audible alert when pressed.
• Makes a visual alert when pressed.

The first property is essential, whilst at least one of the latter two is required. The second matters, but I believe that said behaviour can be configured easily enough (am I wrong?). Does anyone know of such an app? I need it for delivering presentation to noisy rooms as a means of attracting attention.--Leon (talk) 19:45, 7 March 2017 (UTC)

This is a very simple program to write. What language do you want to use? I just taught a VB class last week. You can drop a button in a form (very easy). Use Form.topmost=true to make the form stay above all other forms. Then, go into the onclick function for the button and add my.computer.audio.start to start a sound file - presumably a short alert sound. Making the entire screen flash is possible with a second form that is fullscreen. Display the form. Wait a second. Hide the form. This could all be done in any of the variants of C or Java as well. 209.149.113.5 (talk) 20:07, 7 March 2017 (UTC)

There are a vast number of web pages that play a sound effect when you press a button. Google "beep button" and you'll find a bunch of them. CodeTalker (talk) 23:20, 7 March 2017 (UTC)

March 8

Are BLPs statistically more likely to be semi-protected than non-biographical articles?

I'm not sure if this is the correct place to ask this, but this is a question that has been bothering me for years. Given our BLP policy, are BLPs statistically proportionally more likely to be semi-protected, particularly for longer periods (i.e. a month or more) than non-biographical articles? And as a side questions, what percentage of BLPs are currently semi-protected, and how does that percentage compare to the percentage of semi-protection among other types of article subjects? Narutolovehinata5 ^tccsdnew 14:26, 8 March 2017 (UTC)

If you have the inkling, the data is available for analysis. Special:ProtectedPages is the full list of all protected pages. Category:Living people is all articles about living people. Category:People is for all people. Wikipedia:PetScan is an utility that lets you develop lists of articles by category structure, so you can find all articles in subcats of main categories (like Category:People). If one were so inclined, one could use some rudimentary programming skills to write a routine to take text dumps from those pages and utilities and cross reference the article titles to develop the stats you seek. The stats don't exist yet, but one could create the stats from the available data with some work. --Jayron32 14:46, 8 March 2017 (UTC)

Where does Ajax come from?

I don't know when it started, but on my Windows 10/Microsoft Edge computer, when I click on the URL, I see a list of five of the web sites I have gone to. I don't know how or how often this list changes. I head to reinstall Windows when my Internet wasn't working right, so now I have a whole new list of five sites, which keeps changing, and I don't know how or why. On Wikipedia, I get a different list when starting to type a section heading or edit summary, and this isn't as useful as I'd like it to be since it tends to be alphabetical and some of those early items I would never use again.— Vchimpanzee • talk • contributions • 18:19, 8 March 2017 (UTC)

When you reinstall Windows, your user history is deleted. Any history from before the reinstall is gone. It is impossible for your computer to use the old history to give you suggestions that it used to give you. If you continue using your computer in the same way that you used to use it, the suggestions will likely become similar to the old suggestions. Is there some reason that you believe that your computer should somehow remember anything from before the reinstall? None of this has anything to do with where Ajax comes from. Ajax came from an old iframe hack in JavaScript that is now a nearly standard methodology to make asynchronous HTTP request in JavaScript. 209.149.113.5 (talk) 21:45, 8 March 2017 (UTC)

I'm pretty sure Ajax came from Achaea. --Jayron32 00:53, 9 March 2017 (UTC)

I don't expect anything to still be there. The suggestions come from somewhere, and that's what I'm asking. On this site, it seems to be a complete list, while for URLs in general, I don't know why the specific sites are being listed.— Vchimpanzee • talk • contributions • 15:34, 9 March 2017 (UTC)

Help accessing content from a very large torrent file

https://purl.stanford.edu/tf565pz4260 The link to the left contains a 4chan archive that contains posts from 2007-2013 (the /b/ forum was purposely excluded from the archive). I’m the creator of the Wikipedia article on the SCP Foundation and know that SCP-173, the first SCP, was posted in the /x/ forum during the summer of 2007 (I’m tempted to say in July, but this could be wrong). Unfortunately, the links are only available in torrent form and exceed 3 gigabytes, which is too big for my computer to download and not in a file type I’m capable of opening. Would anyone with experience using torrents be able to check whether the initial post was saved, or if there are even SCP Foundation posts from the year 2007 (they would be solely in the /x/ forum)? Finding the original post or even a few SCP Foundation threads from 2007 would be a huge contribution to the history of internet culture. I’ll also give a reference desk barn star to anyone who either finds the posts within the archive or who can confirm that they are not in it. Spirit of Eagle (talk) 22:12, 8 March 2017 (UTC)

I had already downloaded it, but all I can tell you about the archive is that it wasn't a sphere.

Ok, in all seriousness: a lot of people will be very reluctant to download a file of that size and search through it. In addition, this archive was compiled from selected threads; about 25,000 of them, and it uncompresses to 20GB, which even fewer editors will be unwilling to search. So it looks to be very difficult to search through and not very promising. However, from the readme: "To request a copy of this data package in uncompressed format, please contact the Stanford Digital Repository at sdr-support@lists.stanford.edu" ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 23:11, 8 March 2017 (UTC)

I've downloaded much larger torrents and I'm not unwilling to help, so I started your torrent. Unfortunately nothing happened, 0 bytes downloaded in about an hour. Guess the file is not available (anymore). I'll let it run for a day though.

Apart from that I don't see why you need our help. A 3GB torrent isn't large, nothing extreme. Please explain. (Even a movie is typically larger, HD movies much larger).

As for the file type (.7z), download winzip, install it, and you're good to go. Jahoe (talk) 23:45, 8 March 2017 (UTC)

B.t.w. I see 2 torrents. I've started them both. In the meantime, please specify exactly what to search for. Jahoe (talk) 23:55, 8 March 2017 (UTC)

I'm looking for a specific post containing the text available here (the actual post may be specifically titled "The Statue" or "SCP-173). I attempted to access the files myself, but was unable to get them open (If this is something that is actually really simple to do, then my apologies; I've had little experience with this type of file). Spirit of Eagle (talk) 03:52, 9 March 2017 (UTC)

There's not a problem in file size or format, but unfortunately the torrent is dead. That is: no seeds and just a few peers without data; 0 bytes downloaded in about 12 hours. That's typical behavior for a dead torrent. :(

Guess you should now email the repository like ᛗᛁᛟᛚᚾᛁᚱPants described above.

You would need about 20GB of disk space, that should be available (or freeable) on an ordinary computer. They'll probably give you an ftp link, downloading 20GB may take time (hours), but you can use your computer for other things in the meantime.

Feel free to call back here if you need further assistance. :) Jahoe (talk) 11:26, 9 March 2017 (UTC)

March 9

Firefox font issues - blurring

Overnight, Firefox was updated from version 51.something to 52.0, during that update there seems to have been a major change to how fonts are displayed. Previously they were sharp-edged; now they're blurred (I think that it's known as "anti-aliasing"), and it seems, slightly smaller. My eyesight isn't brilliant, and the blurring makes text difficult to read, which is an accessibility issue. It's not a fault with MediaWiki, since all websites are affected - even those that don't specify a font, such as some test pages that I put together with a plain text editor.

I've looked in Tools → Options → Content → Fonts & Colors → Advanced..., but can see nothing where I can restore a non-blurry font (or disable anti-aliasing) - indeed, the Options pages seem to use a blurry font as well.

How can I get Firefox to use sharp fonts throughout? --Redrose64 🌹 (talk) 11:38, 9 March 2017 (UTC)

I've just updated and see no difference at all.

The release notes mention no changes in font support or anti-aliasing. See: https://www.mozilla.org/en-US/firefox/52.0/releasenotes/

They do mention removed support for old plugins using the Netscape Plugin API (NPAPI). Does that give any clue? Jahoe (talk) 13:04, 9 March 2017 (UTC)

Are plugins the same as add-ons? The only add-ons that I have are Adblock Plus, and Print Edit.

Looking at the doc that you have linked, it says "When not using Direct2D on Windows, Skia is used for content rendering". Might that be it? I don't know what Direct2D is, nor how to find out if I have it. What is Skia? --Redrose64 🌹 (talk) 20:53, 9 March 2017 (UTC)

Replacement of the same PNG->SVG in multiple articles

Disclosure: I have asked the question at Wikipedia:AutoWikiBrowser/Tasks#Replacement_of_the_same_PNG-.3ESVG_in_multiple_articles before, but not gotten an answer.

Dear Computing Helpdesk. I create SVG replacements for PNG images, as requested in Commons:Top_200_logo_images_that_should_use_vector_graphics. Of course I start with those most valuable, as judged by number of wikipedia articles that use them. Once I have uploaded the SVG to Commons and tagged it as being an svg replacement for the png in question, the wikitext in those articles still needs to be updated. Is there a way to automate or semi-automate the replacement of thes image in the articles' wikitext? The images I deal with are very common logos, used in 100s of articles spread over multiple wikipedias, in the case of icons sometimes several 1000s of articles. Doing this by hand is insane. Can you please help me? Thank you very much. --Lommes (talk) 14:25, 9 March 2017 (UTC)

@Lommes: This isn't really a RD/C question; it sounds very much like a job for WP:BOTREQ. --Redrose64 🌹 (talk) 20:01, 9 March 2017 (UTC)

Thank you. I just asked it there.--Lommes (talk) 20:13, 9 March 2017 (UTC)

ROM/"Recovery" flashing question

I want to check my understanding of Android ROMs and flashing. If I flash a Sony Experia ROM onto a Samsung Galaxy S5 phone would that be a "soft brick" that is easily fixable by flashing a more appropriate ROM using the custom recovery? Is the only way to hard brick a phone by borking the recovery itself or maybe whatever part of the software does the booting until it can hand over to the installed Android ROM? --129.215.47.59 (talk) 15:37, 9 March 2017 (UTC)

Some electronic devices, particularly old PCs and laptops, actually allow you to "update" all of the flask ROM -- including the part that tells the device how to do updates. Most modern devices have a small section of untouchable memory that allows it to boot into some sort of recovery mode. This feature is designed into the flash memory and cannot be bricked.

It looks like the Galaxy S5 is one of the devices which cannot be completely bricked. Do a web search on [ Galaxy S5 Recover Mode ] for several tutorials explaning how. --Guy Macon (talk) 14:58, 10 March 2017 (UTC)

Trace and Delete help

While using “VeraCrypt v1.19” software I noticed one of my HDD consisted hidden 128MB that is untraceable with “Computer Management” window’s “Storage” list option’s “Device Management” option. How do I trace and delete? 43.245.122.245 (talk) 17:04, 9 March 2017 (UTC)

First of all: be careful, it's easy to cause data loss when fumbling with partitions. I don't know of any useful partition management utility running under Windows. I would suggest to run Linux from a live USB stick or live CD, and analyze and manage the HDD with GParted. Any live Linux containing GParted would do the job. Jahoe (talk) 18:36, 9 March 2017 (UTC)

Oh, there's even a GParted Live bootable image. Didn't try it myself (yet!), but it may be just what you need. See: http://gparted.org/download.php Jahoe (talk) 18:58, 9 March 2017 (UTC)

• DON'T DELETE IT. Recovery partitions are usually clearly marked, but I have seen unpartitioned sectors used for this, or by unusual BIOS/UEFI configurations. That being said, I've found that Macrium Reflect is pretty good at this sort of thing. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 19:18, 9 March 2017 (UTC)

I agree, don't delete it unless you know exactly why it's there and what you're doing. It's a trivial amount of space if you're thinking you want to recover the space for other use. Even if it's only a 500 GB disk, that partition is 1/4000th of the disk. CodeTalker (talk) 21:50, 9 March 2017 (UTC)

I strongly suspect this is the Microsoft Reserved Partition. As the article indicates, this isn't actually vital in general, but is used in some cases so it's best to keep it and it is a standard part of a GPT disk partioned by Windows (bootable or not) since I think GPT support was added. If you open diskpart in Windows (just type diskpart into the Start menu or a terminal e.g. Command Prompt or Powershell, and approve admin access), select the disk (select disk 0 or whatever) then list partitions (list partition) it should show the MSR and confirm it's reserved. If you are unsure of which disk to select, you can use list disk and work it out. BTW, IIRC you can delete it with Diskpart but I strongly don't recommend it and this won't zero it anyway. If you are worried about confidentiality you could zero it without deletion (well you could delete it and recreate it but this seems unnecessarily complicated), it isn't really intended for long term storage so anything which relies on it for that for important functions is dumb anyway. There's a fair chance it's already all zero. However the far better solution is whole or nearly whole disk encryption which covers the MSR. Remember that even if you delete it, if you just leave it as empty space it's still possible tools will store data there anyway. Also when you don't really know what you're doing, I question the usefulness of worrying too much about the slight chance something you don't want people to see is stored in the MSR compared to the much more likely other things. Nil Einne (talk) 09:26, 10 March 2017 (UTC)

I second all of the excellent advice above, with one minor addition. If you have serious adversaries (as in you work for the CIA or Wikileaks or you are Edward Snowden) even the slightest risk from leaving some small part of your disk unencrypted may be an unacceptable risk. The problem is that if you have that sort of adversary you may already have a hardware keylogger installed, so nuking that small partition will do nothing to increase your security. You need to buy a new computer from some random retail outlet, nuke Windows, and install a Security-focused operating system that is itself encrypted with VeraCrypt. For the rest of us, follow the advice given above. --Guy Macon (talk) 15:40, 10 March 2017 (UTC)

March 10

mature OS besides Windows Linux and Mac

Besides these three OS is there any other non experimental OS for PC? — Preceding unsigned comment added by 31.4.139.75 (talk) 16:25, 10 March 2017 (UTC)

OS/2 is the only other one. Btw. Linux is infact part of the huge Unix-branch. I dont think there are any other PC-OS that rose up to maturity. There are multiple branches of unix, like Linux and FreeBSD. --Kharon (talk) 16:50, 10 March 2017 (UTC)

CP/M was a fairly widespread mature operating system through the early 1980s. Many of the conventions used in MS-DOS came from CP/M. --Jayron32 17:21, 10 March 2017 (UTC)

Solaris_(operating_system) began in the 1980s and is still used, although it's an enterprise architecture, not something you'd run on your laptop. OldTimeNESter (talk) 17:49, 10 March 2017 (UTC)

It depends on how you define what is "mature". Ruslik_Zero 20:56, 10 March 2017 (UTC)

I would not lump BSD in with Linux. I think BSD is an excellent solution for anyone wanting a "mature OS besides Windows Linux and Mac". --Guy Macon (talk) 21:06, 10 March 2017 (UTC)

And among current BSDs, OpenBSD and FreeBSD are quite mature and feature-rich. --Stephan Schulz (talk) 22:23, 10 March 2017 (UTC)

And if you find FreeBSD too difficult, TrueOS is probably the most popular FreeBSD variant targeted at ease of use for a desktop environment, although our article on FreeBSD lists others. Nil Einne (talk) 13:44, 11 March 2017 (UTC)

• Define "OS" in the context of that question. Are Debian, Ubuntu and Linux Mint the same OS? What about Ubuntu 4.10 and Ubuntu 16.10? What about the same version, but compiled with slightly different options?

Of course the OP meant "how many OS families", but depending on what cutoff you take for "family" I suspect you could answer the question in multiple ways. Tigraan^{Click here to contact me} 15:09, 11 March 2017 (UTC)