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December 27

Help with Installing a Dual Boot on an Ancient PC

I am currently sitting in front of an ancient PC. Here are its specs:

AMD Athlon 64*2 Dual Core Processor 4600+ 2.41 GHz, 1.93 GB of RAM, 74.5 GB of C: drive, about 39.3 GB of which is unused, running Windows XP, Home Edition, Version 2002, Service Pack 3.

The machine itself is physically sound, except for a rattly cooling fan. It seems a waste to dispose of it just because it has been replaced by a more up-to-date machine. So, I'd like to use it to learn how to set up a dual boot for a suitable version of Linux, then use the machine to run OpenOffice and a suitable web browser (probably something like Firefox or Pale Moon). Problem is this: I don't know what version of Linux would work best on this hardware set-up. Any help or advice on this would be much appreciated.

If possible, I'd like to be able to read existing files in the existing directory structure from Linux. I've heard that this is possible, but don't know how it can be made to work, so any comments on this would also be useful.

Thanks in advance for your assistance. — Preceding unsigned comment added by 62.56.107.96 (talk) 03:58, 27 December 2016 (UTC)

Does it have a CD drive ? If so, and if it has the option to boot from the CD (which is almost certain, if it has a CD drive), then I suggest the following:

1) Set the boot order to CD first, then hard drive.

2) Place a Linux boot CD in the CD drive and reboot, when you want Linux.

3) Remove the Linux boot CD and reboot to get Windows XP.

It's also possible it has the ability to boot from a flash drive, in which case you could do the same thing using that, but your more ancient PCs may lack this capability. A really ancient PC may also have the ability to boot from floppy disk, but those probably aren't big enough to hold a useful version of Linux, so that would mean you would need to copy most of the Linux files onto the hard drive, and the floppy would just start the boot sequence, using those files on the hard drive. A full boot manager is another option, but that seems more complex, to me, as you need to coordinate between the boot manager and both the Windows XP and Linux boot software, and changing any of the 3 might mess things up. StuRat (talk) 04:04, 27 December 2016 (UTC)

I don't think many machines were booting from a floppy by the time of dual core processors (though anything is possible). According to this and my own experience, most computers will run through a sequence of trying to boot from various devices (floppy first, then optical, then hard drive or whatever), so it's unlikely he'd need a floppy-sized version of Linux (or workaround). Matt Deres (talk) 13:13, 27 December 2016 (UTC)

Ubuntu Installation on External Hard Drive

Hello. I am a bit of a computer noob, currently have a Macbook Pro, and am looking to start working with Ubuntu. I have seen that I can 'boot from a USB'. Am I right in thinking that this is different from partitioning your hard drive? (I have read that I shouldn't do this on on Mac) I have an external hard drive that is 1 TB I think. If I partition this, and format the partition correctly, can I install Ubuntu on this partition and just run it normally through my Mac as long as it is plugged in via USB? Will there be any problems running it this way? Sorry for the noob questions, and thanks for your help! 79.66.101.143 (talk) 21:17, 27 December 2016 (UTC)

• Helpful links: Check out [1]. Also, the forum folks at [2] saved my skin a couple of times.

Booting refers to the process by which the heap of electronics in front of you becomes a computer capable of taking input from the user and performing operations. Without getting into the specifics, what 99.9% of owners of electronic devices do is that they buy their device in a physical state that is configured to boot on a specific part of its internal memory, loading the operating system located there.

It is nonetheless possible to boot from another memory location, including from a USB stick or whatnot. This generally entails a performance penalty as external locations are usually harder to access for the hardware, and the computer will need to access those files a lot of the times. While you could configure your bootloader to go the external drive every time, it clearly is an inferior solution compared to a hard-drive install, ceteris paribus, and from my first link above I would venture it is not impossible to do a hard drive install on a MacBook Pro. Tigraan^{Click here to contact me} 21:59, 27 December 2016 (UTC)

Linux is really very easy (and in many ways far better) but it is not Windows. So take some baby-steps first. Suggest you instal (say) Linux Mint or Ubuntu (both the same in this context) on a pen drive to get familiar with Linux. Questions about partitioning can come later when it makes more sense to you. Then you can take advantage of the 'free' Linux tools available to partition hard drives. --Aspro (talk) 22:34, 27 December 2016 (UTC)

How does Linux not being Windows help a Mac user? Nil Einne (talk) 23:31, 27 December 2016 (UTC)

Well, Windows does an awful lot of stuff automatically. It searches for missing drivers, and then downloads and installs them without being asked. With Linux, you're on your own. I foolishly bought a Raspberry Pi and quickly became frustrated at the steep learning curve that required me to:

• know what driver was missing
• know what version it should be
• manually download it (had to learn how to do that)
• try manually installing it (had to learn how to do that)
• learn all about modifying file permissions because installation was blocked
• try several dozen times to install, using various combinations of file permissions
• uninstall mess-ups that I made in the above processes (had to learn how to do that)
• uninstall mess-ups that I made in trying to uninstall mess-ups
• accept that some mess-ups would never be uninstalled and would forever consume space in the SD card memory
• try very hard to remember all the steps that did work for next time
• accept that some features would never work because of missing libraries (Linux doesn't tell you which ones)
• spend sleepless nights pondering why the writers of Linux would reset file permissions when issuing an update or upgrade

No doubt if you're a dedicated nerd who loves typing commands on a command line interface and playing about for hours and hours, you'll just love Linux. Otherwise, you'll get a real appreciation for just how wonderful Windows is. Akld guy (talk) 00:36, 28 December 2016 (UTC)

No. Far from a geek. Just found that Linux is easier to use and doesn’t keep throwing up problems which I have to spend time on to fix . Time is money, thus Windows is very much more expensive (note that Microsoft has dropped the claim that windows offers a lower total cost of ownership because it focused IT people to look at the TCO and found it more expensive to maintain). Of course Window has no learning curve at all Ho Ho Ho. Microsoft: The Windows 8 learning curve is 'real and needs to be addressed'. As pointed out above Linux is Not Windows. So of course your going to experience problems if one retains the Model T Ford attitude when trying to fly a jet. One simply has to unlearn an operating system that only allows you to do what Microsoft only allows you to do, in the Microsoft way, on the computer that 'you' own. Its a billion dollar scam. --Aspro (talk) 02:09, 28 December 2016 (UTC)

This debate started in the year 15, and both sides have only managed to convince themselves that they are correct. But luckily we are all united in our hatred for MacOS. (((The Quixotic Potato))) (talk) 08:13, 28 December 2016 (UTC) p.s. I use all three, and all three have advantages and disadvantages.

I still don't get why there's all this talk of Windows when the question was from a MacOS user without any clear indication they've ever used or want to use, Windows. Nil Einne (talk) 12:13, 28 December 2016 (UTC)

It is the refdesk version of WP:COATRACKING. Just be glad that they didn't decide to coatrack US presidential politics on the poor mac user.

BTW, the correct answer is, as mentioned above, "read https://help.ubuntu.com/community/MacBookPro and do what it says". --Guy Macon (talk) 00:25, 29 December 2016 (UTC)

Not WP:COATRACKING. The OP asked "Will there be any problems running it this way? Sorry for the noob questions,..." which I took to mean that that he/she knew nothing of the pitfalls of Linux/Ubuntu. I pointed out that, unlike with Windows, those OS's require a tremendous amount of familiarity with drivers and libraries that may be missing and how to install them. This is a not insignificant problem. Anyone who thinks they are going to waltz into running and maintaining Linux will get a rude shock. Akld guy (talk) 12:03, 29 December 2016 (UTC)

You may have had a bad experience (maybe because you had a Paspberry Pi, not a normal desktop/laptop?) and indeed Linux isn't a good fit for everyone, but stating it requires a tremendous amount of familiarity with drivers and libraries is generally not true. Usually it just works. Most drivers are build into the kernel, just make sure you have a somewhat recent version. If not, open some utility and select the driver you want (usually one of "tested open source", "proprietary" and "experimental") and it will be installed automatically. If you install software the easy way, the required libraries are downloaded and installed automatically. I've used Linux for over 10 years now, never had any problems with drivers or libraries. Not now, not when I started. Furthermore, the reference desk may not be the best place to ask practical questions on Linux. Every major Linux distro has its own forums. Those for Ubuntu can be found at https://ubuntuforums.org/. There you'll find many experienced users who can help with any issues you encounter. PiusImpavidus (talk) 12:45, 29 December 2016 (UTC)

As User:PiusImpavidus said`: Usually it just works were as with Windows, Microsoft always tell us it always works... err... well just. Linux may have a steep learning curve but modern Linux is now easier than the Windows learning curve. Place a live Linux Mint onto a pen drive and play around with it. You may find that you drift over to Linux for the same reasons I did. And it gets worse and worse with 100 common Windows 10 problems and how to solve them. Being self-employed, time is money to me and came to find that Windows is just a waist of time and money and I am not enough of a geek to fix all its continuous problems. Especially, when MS upgrades one's computer (without your permission) and buggers it up leaving one with a useless computer. Microsoft is now apologising -yet again. Typical of them. As Bill Gates was quoted as saying: Do it first and ask for forgiveness after. But 'who' has to pay for Micorsoft's continuous efforts to rule the IT world?--Aspro (talk) 17:11, 29 December 2016 (UTC)

You still seem to be missing the point. As I've said 3 times now, WTF does Windows have to do with it? There is zero indication that the OP has even ever used Windows or is going to be basing anything on Windows experiences. The only indication we have is that they use a Mac device, which very likely suggests they use OS X so the only relevant comparisons are between OS X and Linux. Nil Einne (talk) 18:17, 29 December 2016 (UTC)

comment:The point is, that an operating system is an 'operating system' and what goes for the ubiquitous Microsoft also goes for Apple – they both use the same chip sets. How To Install Linux On A MacBook Pro Retina. The OP probably has to use Windoz at work and although he admits to being a bit of a computer noob he can surly be able to read between the lines without it being have to spelt out as if he is a complete and utter idiot. By now, he has probably run this past his IT guys at work and has Linux running on his Mac. Whether he finds the experiences pleasurable or whether he is battling the step learning curve by taking on to much at once, too quickly, is not for us to guess at. But Apple uses BSD, so the Linux file structure etc. may not be too unfamiliar to him.--Aspro (talk) 17:03, 31 December 2016 (UTC)

Again there is no evidence that the OP has ever used Windows. "Probably" is not relevant when the OP has already provided info on what they do use. (And if it was really felt necessary, perhaps a link or two, but not the extensive back and forth about the merits and problems of Windows. Yes we all can get distracted from the main point at times, but it's also easy to acknowledge that this has happened rather than suggesting it was relevant to the original question. E.g. it's obvious that pointing out how incredibly off-topic something is like this is itself offtopic although it can help the OP if it refocuses the question, albeit it's clear by now that's a loser.) And as for "operating system is an 'operating system' and what goes for the ubiquitous Microsoft also goes for Apple", that's probably the dumbest thing said in this thread this far. If that were true, then there would be no need to provide any info since what goes for Windows, would not only go for OS X but also go for Linux. (Note that I was not criticising general stuff e.g. Tigraan's explanation but all the stuff specific to Windows like how it's different from Linux or whether Windows or Linux is better.) As for chipsets, that also has no relevance since the issue of concern wasn't what chipsets were used but whether the discussions relating to Windows were helpful. In other words, giving the OP info on why Linux is not Windows is of no use when there is zero actual evidence the OP is expecting Windows, because there is zero actual evidence they've even used Windows. Likewise explaining how Windows handles hardware compability different to Linux is also useless when what the OP needs to know is how OS X is different from Linux in that regard. (Incidentally, while the basic hardware tends to be the same, as the source you provided notes and I knew before reading this thread despite never having ever used a Mac, Macs are intentionally generally incredibly locked down much more so than nearly all Windows computers, often with special Apple firmware for a lot of components. This doesn't generally make a difference for the OS but it can. It does make a difference when you want to add a new SSD or GPU but can't because it has the wrong firmware. Of course this also means the possible hardware is far more restricted so it's far easier to know if you're likely to have compatibility problems. Point being, if you didn't know all this, it again begs the question why Windows was brought up.) So yes, I'm still waiting an explanation of what was the purpose for all that Windows junk. I'm guessing non is forthcoming. Nil Einne (talk) 20:37, 31 December 2016 (UTC)

WIMP (computing) --Aspro (talk) 21:43, 31 December 2016 (UTC)

December 28

Can't upload to Google drive

Hi. I tried to upload a movie that I downloaded with Utorrent from my Android cellphone,and I get an error message saying that the upload can't be scheduled. What do I do to fix the problem? I don't have this problem when uploading other files,just the one. — Preceding unsigned comment added by Uncle dan is home (talk • contribs) 03:42, 28 December 2016 (UTC)

This sounds similar (((The Quixotic Potato))) (talk) 08:06, 28 December 2016 (UTC)

December 29

Why no virtual 8086 mode in x86-64 long mode?

Why is it that microprocessors using the x86-64 architecture have virtual 8086 mode turned off when the processor is in long mode, even though these same processors are perfectly capable of running virtual 8086 mode (as demonstrated by the fact that they run virtual 8086 mode just fine when running in legacy mode)? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 02:09, 29 December 2016 (UTC)

I don't see any reason to think it's any more complicated that that suggested by our article (x86-64#Architectural features Removal of older features) namely the removal of features that are no longer needed from the new architecture. Such cleaning up of stuff (architectures, software etc) by removal of unneeded legacy features isn't uncommon and is generally considered good practice. Nil Einne (talk) 06:06, 29 December 2016 (UTC)

...except that virtual 8086 isn't an "unneeded" feature, not even close, given that its removal breaks compatibility with all 16-bit applications, even widely-used versions of such.

Is there some way to override or remove the long-mode disabling of virtual 8086 mode? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 09:24, 29 December 2016 (UTC)

Why do you believe that 16-bit application compability was considered significantly important to the designers of the x86-64 architecture? I use a lot of crap, but although I've been using Windows x64 since XP and single core Venice days, mostly I only ever encountered it with crappy programs which still used 16 bit installers. That and DOS programs, but while the later was mildly annoying in 2006, by now DOSbox is a far better alternative. (Well maybe it was then too, but I'm not so sure since IIRC I did sometimes have performance problems albeit maybe this was because of upscaling modes.)

Note also that for the people that matter most i.e. business and enterprise customers, even if they did have 16-bit applications they needed to keep around, it's not clear if they'd want them running on a processor running in long mode (and a x86-64 OS). It's likely such code would be something which is sufficiently important to keep around, but which for whatever reason they could upgrade. The more complicated you make things, the more likely something is to break which would generally defeat the purpose of not upgrading the code. In other words, while I can't find a source which explicitly says so (I did look), there's good reason think the designers felt similar. It's also worth considering there's a fair chance this decision was made twice. I don't know enough to be sure, but I wouldn't be surprised if Intel could have added virtual 8086 mode to their version of long mode without breaking compatibility with AMD64, but they too decided it wasn't worth it. Of course they'd also have to figure it may not be used if a major player (at the time) didn't have it, but they weren't generally shy about adding their own features.

As for your later question, are you actually reading the articles linked to or just linking to them for fun? As the Virtual 8086 mode#64-bit and VMX support article notes, there are ways you can use virtual 8086 mode when running in long mode relating to virtualisation. Unless you know what you're doing however, it doesn't sound like any of them are that well supported other than the basic of running the code on an operating system which does support 16-bit code running as a virtual machine. (And if you're talking about Windows I'm pretty sure it's basically the only option besides pure emulation.) Which technically could be done before VT modes were added anyway. (And the fact this doesn't seem to be that well supported also sort of suggests many felt it wasn't that worthwhile.)

Nil Einne (talk) 10:03, 29 December 2016 (UTC)

The answer is that probably nobody thought about all consequences of the virtual 8086 mode removal. The same thing happened with the removal of segmentation, which made it impossible any virtualization in the first 64-bit processors (in the long mode). To fix these problems a hardware virtualization support was added later. Ruslik_Zero 20:45, 29 December 2016 (UTC)

They didn't really remove anything. To allow switching between V86 and long mode (in particular, handling V86-mode faults in 64-bit OS code) they would have had to define a new protocol for that, implement it in silicon and/or microcode, and support it forever. It wasn't sensible to add yet more cruft to the architecture when emulation works fine. It's (far more than) fast enough, it's more flexible, and it's more secure because it doesn't need any special kernel support or privileges. -- BenRG (talk) 02:18, 30 December 2016 (UTC)

About the segmentation issue, there's some discussion here [3]. It's not from the designers and I don't understand it so can't comment on whether it's well informed but it does probably illustrate the point that such matters are fairly complicated. It could be true that at the time of design it wasn't quite realised the importance to virtualisation but it could also be that the designers felt it wasn't worth it or there were better options. The fact that these only came later and there was a partial reversal on the AMD side but not the Intel side may be due to student priorities coming to play. BenRG also has good point that when you're designing a new architecture it's not so much should I remove this but should I add this legacy feature? In any case regardless of the good our bad of the removal of segmentation, I haven't seen any evidence there was really any feeling the same to Virtual 8086. Nil Einne (talk) 04:07, 30 December 2016 (UTC)

swproxy.wmflabs.org gets indexed in Google

Probably not the correct place to report this problem, but someone here will know what to do/who to contact.

http://imgur.com/a/EMw8c

The proxy needs to be excluded via robots.txt or noindex-ed (but using robots.txt is probably better).

(((The Quixotic Potato))) (talk) 09:27, 29 December 2016 (UTC)

@Guy Macon: You have the knack, you'll know what to do. (((The Quixotic Potato))) (talk) 09:30, 29 December 2016 (UTC)

The Knack (Dilbert episode)... I am on it. --Guy Macon (talk) 13:59, 29 December 2016 (UTC)

See Wikipedia:Help desk#Trying to understand some odd swproxy.wmflabs.org behavior

QP, I am curious; what did you search on to get the result in the image above? I can;t find a search term that finds that exact page. I found plenty of others though, so I can show that there is a problem anyway, but I am curious about what you searched on. --Guy Macon (talk) 14:47, 29 December 2016 (UTC)

@Guy Macon: Thank you. I have updated the imgur album. My search query was "optimist guide to wikipedia" (without quotes). I live in Amsterdam, so I am probably using a Google datacenter in NL. Try searching for "site:swproxy.wmflabs.org" (without quotes). To find the page I found you can use the following:

site:swproxy.wmflabs.org "optimist guide to"

Happy New Year! (((The Quixotic Potato))) (talk) 17:24, 29 December 2016 (UTC)

Update: I spoke to an ops engineer for the Labs team, everyone is on holidays right now, but they will poke someone in the team after new year. (((The Quixotic Potato))) (talk) 18:29, 29 December 2016 (UTC)

December 30

Calling method in Python 3

Why do you use abs(-3), but not 3.abs()? But 'abc'.upper() is ok, but not upper('abc').Clipname (talk) 12:08, 30 December 2016 (UTC)

How does Python 3 parse a command?

If it sees: print('abc {} {}'.format(1,2).upper(), would it go from left to right (print, which string?, create string, capitalize), or would it follow other approach? Clipname (talk) 12:10, 30 December 2016 (UTC)

If you want to see, in general, how Python parses something, you can use the ast module. It parses your sample code and builds an abstract syntax tree. It gives you a way to walk that tree. To simplify doing that, I used this pretty printer. For your example, that produces:

Module(body=[
    Expr(value=Call(func=Name(id='print', ctx=Load()), args=[
        Call(func=Attribute(value=Call(func=Attribute(value=Str(s='abc {} {}'), attr='format', ctx=Load()), args=[
            Num(n=1),
            Num(n=2),
          ], keywords=[]), attr='upper', ctx=Load()), args=[], keywords=[]),
      ], keywords=[])),
  ])

-- Finlay McWalter··–·Talk 13:48, 30 December 2016 (UTC)

May one assume that you appended ')' to the sample? —Tamfang (talk) 22:16, 31 December 2016 (UTC)

Downloading paths

Could your download LimeTorrent stuff via uTorrent? 27.147.226.140 (talk) 12:41, 30 December 2016 (UTC)

Yep. www.limetorrents.in contains magnet links which can be used in uTorrent. Personally I prefer using Deluge instead of uTorrent because Deluge is free, opensource software that does not contain any bad stuff. (((The Quixotic Potato))) (talk) 20:34, 30 December 2016 (UTC)

Internet Connection Issue

While I'm using my PC someone minimises my windows, toggles with it, also sometimes opens up porn stuff. What do I do? How do I block this? I require an instant solution please. 27.147.226.140 (talk) 18:00, 30 December 2016 (UTC)

You can read our Adware#As_malware article. Ruslik_Zero 20:25, 30 December 2016 (UTC)

I recommend using the free version of Malwarebytes Anti-Malware and making it scan the entire computer. Click here and follow the instructions on screen. It may be a good idea to also get a virusscanner. I would recommend the free trial version of ESET Smart Security (which used to be called ESET NOD32, we need to update the article). The trial versions of both are completely free, and you can uninstall them after using them. (((The Quixotic Potato))) (talk) 20:31, 30 December 2016 (UTC)

You should also be very careful about entering any passwords, and especially any banking details on that computer since if another party can gain control then they have probably installed a keystroke logger to capture everything that you type. Dbfirs 20:39, 30 December 2016 (UTC)

Changing some of your passwords (e.g. e-mail, banking, facebook) may be a good idea; but please do that on a computer that is not infected! (((The Quixotic Potato))) (talk) 20:42, 30 December 2016 (UTC)

... and don't use the passwords on the infected computer until you are absolutely sure that you have removed all infections. The guaranteed method is to backup your data, format your hard drive and reinstall everything, then check all your backup media for infections before using them. If the malware is unsophisticated then just running a few anti-malware programs as suggested above might remove it, but some malware tends to reinstall itself very cleverly. Dbfirs 20:47, 30 December 2016 (UTC)

@Dbfirs: Nice teamwork! (((The Quixotic Potato))) (talk) 21:09, 30 December 2016 (UTC)

Where did the circle go?

I have Windows 10 and Microsoft Edge. I clicked on the X in the upper right corner but the URL and everything else at the top of the screen was still there, even if nothing worked. This has happened before. After some time had passed, I happened to look at the screen and saw "Where to next?" and saw a list of options, all sites I go to frequently. After I chose one, I noticed that at the top of the screen where the name of the web site is, the rotating circle (not actually a circle but a group of dots that chase each other in a circle) did not appear to the left of the web site name when I would click on any link of type a URL. Most of the time, that circle is there when I am waiting for a site to come up.— Vchimpanzee • talk • contributions • 22:09, 30 December 2016 (UTC)

One more detail. I got a message at some point that a site was slow due to a long-running script and there was a button to stop the script. When I did this, everything I had done since I clicked on the X was gone. A Yahoo email I was composing reloaded with the original content before I had added anything, and whatever site I was on disappeared and was replaced with a site I had been looking at earlier in the day. And the circle was back.

I should mention that shortly after all this, I got a message saying the computer would shut down for major updates. The Internet has worked so much better since those were completed. Just in case anyone is suggesting updates or anything.— Vchimpanzee • talk • contributions • 22:15, 30 December 2016 (UTC)

A group of pure white dots that chase each other in a circle appears when you're loading Windows and when you're using programs outside of the normal Desktop mode. It's fundamentally the same idea as the hourglass that was used in Windows at least as far back as the 3.1 days. Is this circle the same as that one, or are you describing something different? Nyttend (talk) 12:03, 31 December 2016 (UTC)

I don't know what normal desktop mode is but this is "normal" for me.— Vchimpanzee • talk • contributions • 16:41, 31 December 2016 (UTC)

Did you use Windows 8 at some point? If so, you'll remember how you could use it in a default mode whereby only one program could be used at a time, or you could run it in Desktop mode in a manner comparable to previous versions of Windows. That's what I mean by normal desktop mode, and by "outside of" it I meant the default mode. Sorry I can't explain myself better; I absolutely hated the one-at-a-time mode and used desktop 100% of time once I figured out how to get it to work. I've always used the desktop mode since getting Windows 10, so even though I've had it for maybe a year, I can't remember if W8's non-desktop mode is an option in W10. Nyttend (talk) 04:10, 1 January 2017 (UTC)

I bought the computer a year ago with Windows 10 already installed.— Vchimpanzee • talk • contributions • 18:26, 1 January 2017 (UTC)

And to get to the internet I click on the "e" at the bottom of the screen. What happens when I get there is essentially the way I've always done it.— Vchimpanzee • talk • contributions • 18:30, 1 January 2017 (UTC)

FWIW from a non-technical user: I too am now using a Windows 10 PC, which of course came with the web browser Microsoft Edge (the "e" you're clicking), and on which I have also installed Mozilla Firefox, which I much prefer for both useability and aesthetic reasons. I have noticed that when I want to surf the net, opening Edge often takes significantly longer than opening Firefox. This might be in part because Edge insists on opening a large page of news and advert items called "My feed" (which I can't get rid of, and which I assume take some time to all complete loading up, sometimes with glitches), whereas Firefox merely shows a search box and a few generic remarks (and sometimes appeals for donations). I also get far fewer "freezes" on Firefox than on Edge. {The poster formerly known as 87.81.230.195} 2.122.62.241 (talk) 21:05, 1 January 2017 (UTC)

December 31

What is TCP port 1374 used for?

My firewall logs show an inbound TCP connection from a server at 104.28.15.88 (CloudFlare) to port 1374. Googling that port number only turned up the name of a service called "molly" associated with "EPI Software Systems" but absolutely nothing about what the service is supposed to be for. What exactly is this service? 69.40.146.46 (talk) 04:12, 31 December 2016 (UTC)

• I suppose you found [4]. That port is in the "registered" range, so well-behaved applications should not use it as a randomized port number, if I remember correctly (that is what the dynamic range is for - if you have the courage to read it, RFC 6335 should describe the whole system). Could be a portsweep looking for vulnerabilities, who knows. Tigraan^{Click here to contact me} 16:31, 31 December 2016 (UTC)

• Right, yeah that's basically what I was thinking. Strange thing though is that there is just nothing at all out there describing this so-called "molly" protocol. You would think that someone would have documented it at some point, but apparently not! 69.40.146.46 (talk) 18:13, 31 December 2016 (UTC)

• Information on Molly is here: [ http://www.veeco.com/products/growth-control-and-scheduling-software-for-mbe-systems ]. The company that sold Molly used to be called Applied Epi -- were they bought by Veeco? I only worked on a Molly system once and it was years ago, but if I remember correctly from studying the manual that bit about "Flexible architecture allows new components and instruments to be easily integrated—supports other process control hardware connected through standard interfaces" is talking about port 1374. I doubt that any real-world uses ever go farther than a LAN. --Guy Macon (talk) 18:50, 31 December 2016 (UTC)

Exactly what I was looking for. Thank you so much! 69.40.146.46 (talk) 19:26, 31 December 2016 (UTC)

How to read Kindle books on iPad?

I buy Kindle books from Amazon but my country cannot buy Kindle and get Kindle iPad app. How to read Kindle books on my iPad? --Curious Cat On Her Last Life (talk) 05:52, 31 December 2016 (UTC)

• @Curious Cat On Her Last Life: Does Amazon_Kindle#File_formats help you? (In particular, is Calibre (software) able to perform a conversion in a format you can read?) Tigraan^{Click here to contact me} 16:11, 31 December 2016 (UTC)

Almost definitely not by default due to DRM. However probably an Apprentice (not related to The Apprentice AFAIK) called Alf could help. Although this does require you're able to actually read the books on your computer. If you can't convince the Kindle Windows program to work because of where you live, you're basically SOL since AFAIK Kindle DRM as with quite a lot of DRM, is only partially broken. (You can remove it if you have the necessary keys, but you can't generate them yourself so you need to get them from the DRM provider.) Nil Einne (talk) 20:19, 31 December 2016 (UTC)

What is an Apprentice called Alf? What is SOL? --Curious Cat On Her Last Life (talk) 04:28, 1 January 2017 (UTC)

The apprentice is https://apprenticealf.wordpress.com/ and is referring to DeDRM Tools. I've never used them so can't verify their usefulness. SOL means Sh** out of luck.-gadfium 04:51, 1 January 2017 (UTC)

Smartphone memory problem

Whenever I try to download and install some small apps from Google Play on Samsung Galaxy Gio, there's a message about insufficient memory, even though the internal phone memory has 24 MB of free space and SD card has 1,84 GB (running on Android 2.3.4). For instance, today I was unable to install one 8,10-MB app. How is that possible? Brandmeister^talk 10:49, 31 December 2016 (UTC)

Not all apps can be installed on a SD card and the remaining internal memory seems to be very small so there may be some issues even if technically it is not used up completely. Ruslik_Zero 17:52, 31 December 2016 (UTC)

You could try moving some other apps or their data storage to the SD card. Dbfirs 18:57, 31 December 2016 (UTC)

My phone has a setting that allows me to control what type of data gets stored where (internal memory or SD card). (((The Quixotic Potato))) (talk) 19:25, 31 December 2016 (UTC)

Not quite computing, but it's at least electronics...

Cable box is a disambiguation page for cable box (outside) and cable box (electronics); the latter is a redirect to Cable converter box, the thing that sits on your TV and enables it to process the cable signals. Meanwhile, Commons:Category:Cable television has a subcategory for Commons:Category:Set-top boxes, and hmm, is there a Set-top box article? Yes, and "A set-top box (STB) or set-top unit (STU), also colloquially known as a cable box is an information appliance device..." that lets your TV convert cable signals, satellite signals, and normal television.

So are a cable converter box and a set-top box the same thing or different? They seem to me to cover the same topic, but they've been around since January 2008 and the undated UseModWiki era respectively, and it would be rather unusual if we'd had parallel articles on the same type of object for just almost nine years with nobody getting around to merging them. Nyttend (talk) 12:01, 31 December 2016 (UTC)

"Set top box" is a much broader term that includes cable converter box, digital television adapter, satellite decoder and several other types. Dbfirs 13:01, 31 December 2016 (UTC)

data into PC

If I wanted to transfer data into a PC (from an MCU), FAST, what are the options? RS-232--USB bridges only work up to 115200 baud, which is ~11 kBytes/s. LPT port, ~1 MByte/s, basically dead, no software support whatsoever. USB, too complicated for bitbang. Asmrulz (talk) 15:53, 31 December 2016 (UTC)

What does MCU mean? Ruslik_Zero 17:50, 31 December 2016 (UTC)

It means Microcontroller, and most microcontrollers can't do much better than 115200 baud RS-232/RS-422/RS-485 using an internal UART. I says "most" because you can get an ARM Cortex with gigabit Ethernet, USB 3.0, SATA 2.0, and PCI Express.[5] Other common microcontroller protocols are I2C, SPI, and occasionally you might see CAN. --Guy Macon (talk) 19:08, 31 December 2016 (UTC)

January 1

why is the insertion of leap seconds such an issue for software?

The corresponding article to it gives some hints. However how does it crash a Windows or Linux server? And why readjusting the clock (by hand or automatically) won't crash the system? — Preceding unsigned comment added by 31.4.142.11 (talk) 11:56, 1 January 2017 (UTC)

This is a topic that isn't easy to describe to a non-programmer audience. It is rife with technical details. If you aren't familiar with how computer programmers use computer hardware and software to represent time, start by reading Real-time clock and system time. If these subjects are too technical, please accept this summary: there is a lot of complexity involved in getting a high-speed digital computer to understand time in the format that humans expect. Small errors can occur in any of the layers of the system that work with the clock.

A large number of totally distinct bugs might occur in response to the UTC leap second; among the most common category of bugs are softwares that incorrectly assume a monotonic increase in system time. When time is reported by certain programmatic conventions, monotonicity is not guaranteed. This means that it is not correct to use simple arithmetic to compute time-differences between two arbitrary time-stamps: a sophisticated API must be used to ensure accurate and valid time interval calculation results. Failure to use such an API may yield negative, zero, or other wrong values. Software that uses wrong time interval values may propagate a malformed result, yielding a crash.

An excellent technical overview is presented in the Java language utility java.util.date, including links to further discussion.

A different category of bugs arise from the time zone and leap-second database. Computers must interpret a complicated database file and decode the schedule for when a leap-second is due. This database file is updated, and modern computers must retrieve a new copy from a trustworthy source. The most common format for this data file is the tz database. Read and understand its specification; it is documented by IANA on their website and in RFC6557 and RFC5545 and RFC4833 and ISO 8601 and ... any skilled programmer will recognize that correct and complete handling of this format is prone to human-error. If a human-error persists in software that runs on your computer, your computer may execute undefined behavior ...(it may "crash").

In other programming environments - like linux kernel - things get even more complex, because software must also deal with machine-specificity. Here is a mail archive for Kernel's handling of ISO 8601: a patch to mktime64. Here is a discussion of how leap second impacts secure execution in kernel 2.6 (... which is now "quite old"): ChangeLog-2.6.34.13. On some computer architectures, the system clock is part of the security scheme, largely to preclude replay attacks (or to make replay attacks tamper-evident by use of a nonce or hardware counter). Weirdness with the leap second causes certain benign activity to look an awful lot like a replay attack. Software in the kernel must handle this case correctly, else it may perform undefined behavior. Our eagle-eyed readers will observe that the kernel hackers attribute the correct implementation of the UTC leap second algorithm to Carl Friedrich Gauss. This is, surely, an anachronism for the sake of humor. Ha!

There are immense variations on these themes. Ultimately, to understand how any specific software might fail when face with any specific instance of a leap-second, we need to carefully scrutinize its source-code. But we can lump the failures into general broad categories: arithmetic errors caused by wrong assumptions about timestamps; system errors caused by incorrect or esoteric handling of hardware clock counters; application errors caused by invalid time-zone and localization computation; and so on.

Here's a great introduction to time programming, from W3, the web standardizations consortium: Working with Time Zones.

Hopefully this helps direct you to technical resources. If all else fails, learn to use the thinnest, lightest, all-aluminum computer around: the E6B, whose analog time-calculation capabilities are numerous and widely useful.

For the regular readers who are not familiar with my background, I used to build high precision clocks based on GPS radio signals, and participated in research that used tiny satellite clock errors to indirectly measure the imperfect character of Earth's ionosphere, through which all GPS signals must propagate. The core feature of GPS technology is a group of incredibly accurate clocks that can be used to triangulate an incredibly-accurate location. We would use sophisticated analog and digital electrical circuits, and special software-enabled computers, to ensure clock coherence on opposite sides of the Earth. With effort, we can obtain nanosecond-accurate clock coherency across thousands of miles - as long as we are very very careful. These days, as I pursue an instrument pilot rating, I am engaged in an ongoing metadiscussion with my flight instructors about the trustworthiness of software computers to correctly perform these calculations. Famously, a group of very smart scientists accidentally forgot a tiny software-detail related to a GPS time stamp, and mistakenly believed that they had found faster-than-light communication. Very smart people can make very small errors, and software makes these errors impossible to identify. It is for this reason that, when I can't rely on my eyes and ears, I still trust my stopwatch more than my sophisticated GPS-enabled computer. Think of the speed of light as a very-high-gain time-error amplifier. To a GPS computer, each nanosecond of clock error equates to one foot of position error, which only becomes a problem when you're a few nanoseconds away from an obstacle you can't see. Nano-second errors in stopwatches are intuitive; nano-second errors in software are frequently incomprehensible. Good thing there is never any reason to believe that a software computer might err by one whole entire leap-second!

Nimur (talk) 17:35, 1 January 2017 (UTC)

What language that is interpreted that is usually considered the best one?

What language that is interpreted that is usually considered the best one?201.79.48.89 (talk) 16:50, 1 January 2017 (UTC)

It depends what you mean by "best" (e.g. easiest to learn; most powerful; fastest; most likely to get you a well-paid job, etc), and also by interpreted language, which is not a clearly-defined term. AndrewWTaylor (talk) 17:30, 1 January 2017 (UTC)

"Best" is undoubtedly a matter of opinion; please see the header at the top of the page, which states, "We don't answer requests for opinions, predictions or debate." If you want to ask a question with a factual answer, like "What are the most widely-used interpreted languages today?", we would be glad to give some answers. --47.138.163.230 (talk) 21:35, 1 January 2017 (UTC)