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January 9

Transferring WhatsApp to a new device

I'm trying to move all my WhatsApp data, mainly messages logs, to a new phone. I did the followings, according to the instructions on the website:

Entered Settings - Chats - Chat Backup and created a local backup.
Copied the backup file to the new phone to the location WhatsApp\Databases as msgstore.db.crypt12.
Started WhatsApp and verified my phone number.
The app found the backup and asked to restore it.

When restoring, the process ended at 24% for some reason, and the bigger problem I'm having is that nicknames on groups (gray text near the phone number) don't appear.

How do I solve these issues? Galzigler (talk) 06:07, 9 January 2017 (UTC)[reply]

The file could be damaged. Maybe try the whole process again.

As an alternative, you could backup your messages and restore them through Google Drive. Hofhof (talk) 12:23, 10 January 2017 (UTC)[reply]

Radio

Question was duplicated on the Humanities Desk. Moving the answers there. --69.159.60.210 (talk) 07:55, 10 January 2017 (UTC)[reply]

Client for Cisco VPN that saves password regardless of server policy

Just wondering if there is third-party VPN software that will save login details for a Cisco VPN, and not keep prompting every time? Apparently my new university has banned password saving via server policy settings, and the official client doesn't let me override this. I have a Windows desktop, a Macbook, and an Android phone, so suggestions for any of those platforms would be appreciated.

I guess I could use a batch file to autofill the password via the command line, but firstly I don't know how yet, and secondly I realise that a client which encrypts saved passwords would be more secure. Batch files are plain text, right? Anyway thanks for reading. 95.245.37.196 (talk) 15:24, 9 January 2017 (UTC)[reply]

I use vpnc and save all credentials in the VPN config file. The password is technically pulled from an environment variable set in my bashrc file. 209.149.113.5 (talk) 17:45, 9 January 2017 (UTC)[reply]

You could use a password manager although it may not be entirely automatic [1] [2].

However note that encrypting the save passwords is not really more secure if don't need to do anything to decrypt the password. Password managers generally allow you to enter a master password to decrypt the passwords. This means as long as the master password hasn't been entered or stored somewhere, then your passwords (hopefully) can't easily be recovered. So for example if someone steals your computer edit: and it's off they're hopefully out of luck. (Although there is always some risk the master password has been stored somewhere, hence encryption of all disks is also ideal.) If you don't need to enter a master password or similar (e.g. connect a device) then there isn't really any significant security. This applies to most saved passwords by software itself. (An exception would be where the software doesn't need to save the password, but this may still allow login since the software obviously can.) Note there isn't any need to install software on your computer. A person (e.g. evil maid) just needs to know where the software stores the encrypted password and perhaps the key (if it uses a randomly generated key rather than a standard one). If the key and encrypted password is fairly long, writing it down will take a fair amount longer and the person needs to know a bit more but that's the only real advantage.

In fact, there is a slight risk malware (although malware may also install keyloggers or monitor the software itself if left too long) may be more likely to know about these stored passwords and steal them than your personal batch file. Note also that some software intentionally makes no attempt to encrypt the password for this reason. Some just does some easily reversible modification e.g. a simple cypher.

Nil Einne (talk) 06:30, 10 January 2017 (UTC)[reply]

And here's a list of password managers to choose from. Mitch Ames (talk) 10:40, 10 January 2017 (UTC)[reply]

January 10

Memory use by R (programming language)

Is R's memory management less efficient than other languages like Java or Python? The R (programming language) article could use some expansion around this issue. --Hofhof (talk) 12:30, 10 January 2017 (UTC)[reply]

This is a very difficult topic. R is primarily used for complex mathematical calculations. Most people work with vectors and add/remove objects in the vectors many times. R uses malloc to reserve memory. Doing so for each item added to a vector would make R deathly slow. So, R reserves large chunks of memory and then internally manages the memory in the block. To over-simplify it, R requests a big chunk of memory from the operating system, even if it doesn't really need all of it. Then, R reserves/releases memory inside the block itself. The entire block is always reserved by R from the OS perspective. So, you can say that the memory management is better suited for what R does since it is handled by R. You could also claim that the memory management is wasteful since R reserves more memory than it will use. In my opinion, it is not proper to compare memory management in R to memory management in Java or Python because you are comparing two radically different things without even getting into the specifics of exactly how R's memory management works. 209.149.113.5 (talk) 18:28, 10 January 2017 (UTC)[reply]

Websites for asking questions from certain nationalities

For example I'm trying to identify a music video that's probably German or Austrian and I thought maybe I would have a higher chance of people identifying it for me on a website frequented by German or Austrian people. I've found www.gutefrage.net but I'm looking for more.

I'm also looking for a website where I can reach Czech people to identify a probably Czech movie. I've found http://www.csfd.cz/ but it one of those sites where you have to have a certain amount of points before you can post so I can't use it.

Languagesare (talk) 14:35, 10 January 2017 (UTC)[reply]

[3] seems to be the de WP equivalent of our reference desk. I cannot read Czech but you can try to find a similar page.

If you meant that you want to ask in English I am out of ideas. (Sweden has this but that is not exactly what you had in mind.) Tigraan^{Click here to contact me} 14:57, 10 January 2017 (UTC)[reply]

You could ask, in English, there. Just as we sometimes get foreign language Q's here, I'm sure somebody will be able to translate there. StuRat (talk) 17:27, 10 January 2017 (UTC)[reply]

Thanks, I did that. Languagesare (talk) 19:19, 10 January 2017 (UTC)[reply]

Scroll speed in Chrome vs IE

I'm visiting my father and he's asked me to look at something on his laptop. It's an Asus X540S running Win10.

The issue that he's asked me to look at is that in IE, his two finger scroll on the trackpad will move the page at an acceptable rate. In Chrome however, it is very quick! He, at first, was telling me that it just snaps to the bottom of the page, though it doesn't. It's just so quick that his older eyes couldn't quite catch it. It's even so fast that I would find it annoyingly quick and I have much more dexterity in my fingers than he does.

I think that slowing it down system-wide would be fine but I can't find a way to do even that. Is there a way to slow it down system-wide or more specifically in Chrome? 50.244.0.245 (talk) 17:32, 10 January 2017 (UTC)[reply]

I suggest looking into the Chrome addon "Chromium Wheel Smooth Scroller" or one of the many variants. It adds a lot of scrolling settings - which includes how many lines to scroll and how fast to do it. 209.149.113.5 (talk) 18:21, 10 January 2017 (UTC)[reply]

I've noticed that on Wikipedia that some pages with a large amount of information take a long time in IE before it will do any scrolling whereas Chrome doesn't have that problem. Bubba73 ^{You talkin' to me?} 18:23, 10 January 2017 (UTC)[reply]

The Chromium extension doesn't do anything for the trackpad. I'm not seeing other options for the trackpad... Other ideas? 50.244.0.245 (talk) 20:55, 10 January 2017 (UTC)[reply]

double the number of CPUs by an option

This video says that CPU chips have twice the number of advertised cores for spares if some of them quit working. Is this true? Is it safe to do this? What happens if one of the cores dies after you do this? Does this increase the size of the memory cache too or leave it the same? Bubba73 ^{You talkin' to me?} 18:21, 10 January 2017 (UTC)[reply]

I have not watched the video. Your description is not accurate. CPUs do not have spare cores laying dormant, waiting for the active core to fail. If you don't know much about computers, you might think that you have double the cores in a CPU by using various tools to inspect the CPU. As an example, I have a rather old computer. It has two quad-core CPUs. That means that it has 4 cores per CPU and 2 CPUs for a total of 8 cores. If I look at the CPUs through the operating system, I see 16 cores, not 8. That implies that there are 8 cores on each CPU, not 4. Of course, there are only 4 cores. The CPUs have hyperthreading enabled. Each physical core shows up as two logical cores to the CPU. I can turn off hyperthreading and see only 8 cores if I want (I don't want to). In the end, you simply need to know what you are doing and what you are looking at. 209.149.113.5 (talk) 18:36, 10 January 2017 (UTC)[reply]

The video description begins: "NOTE - This video is a joke..." Dragons flight (talk) 18:38, 10 January 2017 (UTC)[reply]

Whoops, I didn't see that warning. Bubba73 ^{You talkin' to me?} 19:00, 10 January 2017 (UTC) [reply]

Resolved

The important part of user:209.149.113.5's reply is that the 8 logical cores on the real CPU each support hyperthreading, and (to some extent) behave as 16 core. LongHairedFop (talk) 20:07, 10 January 2017 (UTC)[reply]

Yes, I know about that. Three of my current nine desktops have hyperthreading. Bubba73 ^{You talkin' to me?} 21:39, 10 January 2017 (UTC)[reply]

But note that some mainframes (e.g. IBM zSeries) do indeed often have more cpus than sold and available to the customer. They can be activated remotely if the customer buys an upgrade. Apparently, it is cheaper to always ship the hardware than to build different versions and occasionally go through a real hardware upgrade. --Stephan Schulz (talk) 22:34, 11 January 2017 (UTC)[reply]

Some CPUs allow you to enable/disable cores, with proper firmware (e.g., BIOS/UEFI) support. Also, CPUs can be sold with things that are physically present but faulty or disabled by the manufacturer. CPUs can be sold with a locked CPU multiplier. Chips that have a fault affecting only part of the chip may be sold with the faulty portion disabled; for instance, if a defect affects only one core, it can be sold as a CPU with fewer cores, rather than thrown away. As mentioned above, this particular video may be a joke, but there's some basis in reality for similar things. --47.138.163.230 (talk) 04:06, 12 January 2017 (UTC)[reply]

Also another thing that came to mind later: fancy, expensive "enterprise" hardware can support all kinds of things, like multiple physical CPUs and hotswapping of CPUs, not found in your average consumer device. Systems where high availability and reliability are required, such as banking and finance, industrial equipment, control systems on vehicles, medical equipment, etc. frequently feature multiply redundant components, including CPUs. In such systems you can often have backup CPUs which are normally idle, there to take over if a primary CPU fails. --47.138.163.230 (talk) 11:30, 12 January 2017 (UTC)[reply]

Folder Locking Software

Require a folder locking software that opens up a security window to enter password whenever I click on the ‘folder’, something like the ‘BitLocker’ drive locking software. Drive locking seems to be impossible (daunting, risky, tried and tired). It will also be good if the same software can lock files, images, video clips, movies and music files, and so on. Anything you guys used, you guys are happy with that I could use too? 103.230.105.26 (talk) 18:46, 10 January 2017 (UTC)[reply]

Here is a list of best encryption software [4]. If you happen to use OS X, there is built-in encryption capability [5]. SemanticMantis (talk) 20:20, 10 January 2017 (UTC)[reply]

Microsoft Office also has a built-in option to password-protect files. - CHAMPION ^{(talk) (contributions) (logs)} 03:42, 11 January 2017 (UTC)[reply]

Also, you can password-protect a zip file. - CHAMPION ^{(talk) (contributions) (logs)} 03:52, 11 January 2017 (UTC)[reply]

You should take care if using zip. The initial standard encryption is broken and has been for a long time, see Zip (file format)#Encryption. Probably most recent tools will either simply not support this for writing or warn you but it's possible some don't. Newer better methods are supported although as our article mentions it can be a bit messy what tool does what. 7-zip mention in the above link at least (AFAIK) is fairly standard in encryption. You also need to consider if the encryption is able to encrypt the headers including filenames and checksums (well hopefully checksums, since if the format uses hashes people don't have to decrypt your archive to work out what's stored if it's standard and not encrypted).

However the biggest concern with encryption archives but also to some extent, directory or partition like software is you need to take far greater care in not screwing up. It's a pointless for example to encrypt an archive of the sensitive stuff if you earlier stored it unencrypted on the same disk and didn't wipe that after making the encrypted file. Or if you later decrypt the content, perhaps to view it and store this on the same disk. This is less likely with directory or partition like encryption systems since they generally allow the files to be used by the OS without needing to decrypt them separately and likewise to be stored directly encrypted.

I'm assuming content being recovered from the drive/s of the computer isn't a concern this this has never been mentioned before, only from the removable drive but even so there are still risks, which is why whole disk encryption is far better especially if you don't know what you're doing and don't understand the tool. In most cases of course you do have to worry about content being recovered from the disks of the computer since if the removable drive can be stolen so can the computer. Especially if it's a laptop. And in that case you need to encrypt not just the removable drive but the drives of the computer. And even then you should be aware of the limitations, e.g. if someone steals the computer when the decryption key is in memory because it's on and unlocked. Malware. Etc.

Nil Einne (talk) 11:39, 11 January 2017 (UTC)[reply]

January 11

DeepDream and noise

If DeepDream is left trained on the same image for an excessively large number of iterations, does a kind of random noise result? What does that look like? Can you find me an example? Card Zero (talk) 18:10, 11 January 2017 (UTC)[reply]

"Apple Certified Pre-owned" iPhone

I just bought an iPhone 6S on eBay. It was advertised as new but arrived marked "Apple Certified Pre-owned". What exactly does this mean? Will it be in new condition aesthetically, eg. no scratches? Will it have the same life as a new unit? Etc. Amisom (talk) 22:27, 11 January 2017 (UTC)[reply]

Have you tried google? Vespine (talk) 00:30, 12 January 2017 (UTC)[reply]

Yes. I didn't find answers to either of the two questions I asked above. Thanks @Vespine:. Amisom (talk) 08:35, 12 January 2017 (UTC)[reply]

Not sure why it didn't work for you. When I search for 'Apple Certified Pre-owned scratches' or 'Apple Certified Pre-owned scratch' or 'Apple Certified Preowned scratch' or 'Apple Certified Preowned scratches' or 'Apple Preowned scratch' or 'Apple Preowned scratches' i.e. the logical search terms based on your question I find [6]. As for the second question, these sort of things are generally impossible to answer. I mean some companies have return rates for such devices so have a good idea, but they don't tell it to ordinary consumers. Nil Einne (talk) 01:46, 13 January 2017 (UTC)[reply]

January 12

Any virus can make computer on fire?

I know the email about Torch virus is fake but any virus really can make computer on fire? Include normal computers, laptops, phones and iPads. Not include special computers for factory work or airplane. Not include bad hardware example Samsung Note 7 battery unless if virus can cause the fire. --Curious Cat On Her Last Life (talk) 09:24, 12 January 2017 (UTC)[reply]

Maybe not the computer, but it was at one point possible to set the printer on fire. Mitch Ames (talk) 09:51, 12 January 2017 (UTC)[reply]

Or a virus could call the Halt and Catch Fire instruction. Mitch Ames (talk) 09:53, 12 January 2017 (UTC)[reply]

Not actually catch fire, but it was possible for malicious software to physically damage some older computers with a killer poke. Mitch Ames (talk) 09:54, 12 January 2017 (UTC)[reply]

If the device has a lithium ion battery of some sort which would include most laptops, phones and tablets but not desktop computers, it may be possible to change the firmware of the battery charger to cause overcharging or allow over discharging and then attempt charging. Both of these potentially could cause a fire. See some brief discussion of this possibility here [7]. However this assumes that there is modifiable firmware that allows that and there are no additional unmodifiable safety features to prevent this or at least which will prevent them "venting with flames". In terms of charging, one obvious consideration is whether it's even possible for to output sufficient voltage. This documentation for a Sanyo 18650 cell [8] allow up to 4.5V with a faulty charger. Suggesting while it's possible frequently charging to 4.5V may cause sufficient damage to eventually vent with flames, it should not happen after a single instance. Most other components are unlikely to catch fire or cause something else to catch fire. E.g. even if if you turn off the fan (if any) and heatsinking etc means there's a limit to how hot the CPU and GPU are likely to get before they die. And in practice most modern CPUs and GPUs (at least in desktops/laptops) have thermal throttling in addition to a thermal cutoff which normally stops them killing themselves from overheating alone and which often AFAWK can't be shut off. (Well if you're relying exclusively on the builtin thermal cutoff t's possible if you're doing it several times a day for many days you're eventually going to cause sufficient damage to break it. In addition, you may or may not be able to kill it by overvoltage, especially with a computer designed for overclocking.) I do wonder about the VRMs (as stuff like Furmark etc have shown( but you're more likely to just kill them then cause a fire. Nil Einne (talk) 16:25, 13 January 2017 (UTC)[reply]

I have no idea if this would work (and after an incident in Dubai several years ago, I believe standards on harmonic distortion have been improved), but I've speculated that an alternate plan is to make a virus that uses heavy processing power for half of each 1/60 of a second, synchronized with an external time source; this "harmonic distortion virus", let loose in office buildings and hotels or even homes with many computers, might shift the ground voltage for the entire building's electrical system to something close to the mains voltage and (putatively) burn down whole countries, especially when integrated with the approach above. Wnt (talk) 17:42, 13 January 2017 (UTC)[reply]

January 13

Tesla privacy

I was just reading this, which gives me the impression that every charge for every Tesla is tracked from the company's central server, at least where the identity of the car is concerned. It strikes me that this completes an apparent design, since according to some things I read the vehicle apparently collects detailed logs of everything the driver does for about the past 50 hours. [9][10][11]. There is some inconsistency in those: the article about the New York Times gives a strong impression that it was tracking the car's position, while the programmers say that there is no evidence of it storing actual position data... while also saying the file contains encrypted material only Tesla can read. Anyway, I was wondering if you can recommend more data to put this together reliably this goes there, saying the company even gets profiles of how the driver acts on specific roads, but it seems a little hard to follow certain details). My overall impression from the preceding is that by controlling the only power generally available and making electronic connections whenever it is powered, the company knows precisely where and how the "owner" of the car is driving soon enough, but I'd prefer some clearer sourcing before I go on about it in the article. Wnt (talk) 17:34, 13 January 2017 (UTC)[reply]

For your first link, if Tesla gives out free charging to its customers, I see no way to ensure that only Tesla-issued cars are plugged in it without going online. You obviously need some sort of identification to avoid a smart guy to come up with an adapter and suck free electrons. An offline challenge-response authentification is all sorts of trouble (can give details if needed), and a huuuge security liability especially if you are going to bill people with it.

For the rest, well... Computer driving being a game of machine learning, Tesla has a legitimate interest in keeping as much driving data as possible. It will actually improve the auto-driving software. It is certainly more legitimate than, say, Google maximizing the profit they get from auctioning your computing power, bandwidth, and human attention to whoever pays the most to execute their arbitrary code in your browser - err, I mean, delivering ads that interest you. If I was in charge, I would make the thing opt-out but with ten steps before reaching the "disable" button, so that I lose data on the 0.1% of civil right activists that use it but also the criticism that comes with it. Tigraan^{Click here to contact me} 18:39, 13 January 2017 (UTC)[reply]

Actually I was looking for capabilities rather than explanations, since the latter seem pretty simple to come up with post hoc and don't really mean a lot. Wnt (talk) 22:01, 13 January 2017 (UTC)[reply]

Nitpick: on the net, you aren't really taking Tesla's electrons when you charge your car at Tesla's station... you're taking their energy, because for every electron that flows into your battery as elecrtric current, a replacement electron flows back out. In other words, even as you "charge" a battery, you are completing an electric circuit. The battery doesn't end a charge cycle with more electrons than it starts with. Rather, it finishes with the same number of net electrons, chemically emplaced into a higher energy state. The clever user who seeks to steal electrons will find himself carrying an electrostatic charge; the effects of the coulomb force would be macroscopic for any thief who tried to take even a few milligrams of electrons. They'd probably be unable to depart the charging station, even using a powerful high-torque electric motor like the one found on a Tesla. WP:OR - Shall I provide a link to these calculations on Wolfram Alpha? Nimur (talk) 22:37, 13 January 2017 (UTC)[reply]

Nimur, I read the Coulomb force article, but I'm unclear — it looks like the force would either be immensely repulsive (i.e. the thief would get injured so badly he'd be unable to leave) or immensely attractive, but I didn't understand the article well enough to know which of these would be true. Or perhaps something else would happen (e.g. a massive static electricity shock, rendering the thief badly injured); which, if any, of these is what you meant? Nyttend (talk) 01:19, 14 January 2017 (UTC)[reply]

You can look at the analysis of logs which were publicly released in this dispute [12] [13] [14]. It doesn't include any position information but that may have just been because it wasn't relevant to the dispute. Also this was a while ago. Note that although this car was being test-driven, I've never seen any suggestion the logging wouldn't have happened normally although I believe unsurprisingly the journalist was required to allow Tesla to retrieve the logs. Note that I don't actually see anything in those logs that probably isn't required in most fancy cars and probably non fancy ones, with an Electronic control unit obtainable via OBD2 other than the charging stuff. Nil Einne (talk) 04:33, 14 January 2017 (UTC)[reply]

Ambiguity and programming languages

Could a programming language be ambiguous under any aspect? Can we be 100% that a language is not ambiguous, not matter what you express in this language? — Preceding unsigned comment added by 31.4.136.155 (talk) 23:03, 13 January 2017 (UTC)[reply]

In many programming languages it is possible to set up a race condition, the outcome of which is not predictable. Jc3s5h (talk) 23:08, 13 January 2017 (UTC)[reply]

Also, many languages explicitly allow for constructs that have undefined behaviour (in C, e.g. comparing two arbitrary pointers, or the order of execution between sequence points, or, IIRC, dereferencing the NULL pointer). Such ambiguities are often trouble for portability, because different implementations may implement them differently. --Stephan Schulz (talk) 23:22, 13 January 2017 (UTC)[reply]

January 14

Intel 80186 manufacturing

Our article on the Intel 80186 says that production of this chip began in 1982 and continued until 2007. Aside from replacements of older hardware (especially for the embedded system for which the 186 was largely used), what, if any, market would there have been for the 186 by this time? I can't imagine a reason to do anything except replace old parts (and even then, why use a quarter-century-old design when you can upgrade to something much newer and better supported; museum/archival needs would be a tiny fringe of the market) with such an old chip design. Nyttend (talk) 01:15, 14 January 2017 (UTC)[reply]

Lots of military hardware used the MQ80186-6/B, and had very long production runs. If an embedded system does the job you designed it to do, why redesign with a "newer and better" chip. Also few of the more modern chips come in ceramic and glass packages. --Guy Macon (talk) 03:47, 14 January 2017 (UTC)[reply]