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February 5

RAM & ROM on Smartphones

As I understand it so far:

ROM is non-volatile internal memory where (on smartphones [that are not rooted]) the OS (& many apps) are stored.

RAM is volatile internal memory that the apps use (as working space) when they are running.

If a phone (such as the Samsung S3) has 16 GB of internal memory & its specs say it has 2 GB of RAM, does that mean there are 14 GB for ROM?

Also: Am I correct that the trend in the Android OS is to have all the apps loaded in ROM? --JimWae (talk) 09:29, 5 February 2015 (UTC)

That phone has 16 GB of flash memory and (separately) 2 GB of RAM, and some unmentioned amount of ROM. Flash memory is nonvolatile. I think you may be thinking of flash memory when you say ROM. -- BenRG (talk) 10:32, 5 February 2015 (UTC)

A flash drive has non-volatile RAM, but its contents are easily changed. I'm not confusing Flash RAM with ROM. I've seen several phone specs that mention ROM. The Galaxy Core is said to have 16 GB of internal memory, 1.5 GB of RAM, & 8 GB of ROM -- so I guess my simple subtraction is NOT the solution. On phones, ROM seems to be what they use to talk about internal memory that users cannot change (but that perhaps apps can be installed to). It seems to be where (along with the OS) pre-installed apps that cannot be removed (except by rooting) are stored.

What's confusing me is specs having separate numbers for Internal Memory & RAM. The RAM is internal memory, no? ROM is internal memory, yes? What else is there in internal memory? --JimWae (talk) 11:01, 5 February 2015 (UTC)

"ROM" there means built-in flash memory (as mentioned below). So does "internal memory". If you install a custom "ROM" on your phone, that also goes in flash memory. The terminology is inconsistent and confusing. If they quote two numbers, x GB and y GB, and x < y, it's safe to assume that x is RAM and y is flash memory. I don't think any smartphone has anywhere close to 1 GB of genuinely read-only memory. -- BenRG (talk) 22:08, 5 February 2015 (UTC)

this reminds me of the 1 MB (& up) computers that could only use 640K because part of the higher addressed space was the OS. Then HIMEM.SYS was used to swap that content to higher memory (above 1MB address?), and then use some of 640K to 1MB address for RAM.--JimWae (talk) 11:09, 5 February 2015 (UTC)

Go careful. Those terms are thrown around very carelessly in the smartphone world. I'm also not sure where you found the specs you quote; according to Samsung, this device has 8GB 'ROM' and 1GB 'RAM'. What they mean is that it has 8GB of internal flash, though this can be supplemented with a micro SD card to add an extra 64GB. That combined flash memory (8GB + whatever SD card is installed) has to house the permanent storage of both the OS and apps that are installed; according to the page referenced above, of the 8GB internal flash, 5GB is 'user-accessible', which basically means that the OS and the bundled apps you can't uninstall add up to 3GB, leaving 5GB (+ whatever SD card is installed) to install apps and store data.

Flash memory like this is different to what is traditionally meant by 'ROM', where some read only memory is mapped into the memory address space of the processor; this 'ROM' is actually treated in the same way as a hard drive in a computer.

RAM is entirely different. This doesn't hold its contents once the device is powered off and is used for storing the running state of the OS and apps. This state is transient, unless it is written back to flash memory.

In summary, the numbers quoted for RAM and ROM capacities don't relate to each other. This device has 1GB of RAM and 8GB of ROM, of which 3GB is occupied when you receive the device, leaving 5GB for you to install apps and store data. GoldenRing (talk) 11:17, 5 February 2015 (UTC)

OK, maybe it makes more sense now: the Galaxy S4 SGH-I337M (according to Samsung) has 16 GB internal memory, [MAXIMUM] User Accessible Memory is approximately 8.2GB, also has 2GB RAM. The RAM is never? used for storage of files or apps or OS themselves, just for data - temporarily. The external memory [SD card], like a hard drive, stores files (not the OS, but MAYBE some OS settings?)--JimWae (talk) 11:55, 5 February 2015 (UTC)

The Samsung Galaxy S4 is available with 16GB, 32GB, or 64GB of internal flash storage. although the latter is very rare. My 32GB version reports (home -> menu -> settings -> more -> storage) that there is 23.6 GB total space on the internal storage. Thus, there is 8.4 GB missing. There may be some accounted for in differences between GiB and GB, and for file system overhead. However, I suspect most of that is the operating system. As the OS is user-upgradable, I think the phone boots off a small BIOS-type ROM, and which then loads Android from the internal flash drive, much like how a PC boots. LongHairedFop (talk) 12:22, 5 February 2015 (UTC)

Falling Hard Drive

Hello all; my hard drive seems to be slowly failing. It has been displaying bad sector messages in Event Viewer. I attempted to do one final complete backup to another hard drive, by both manually copying and also Windows' built in backup, but the copy stalls and the "activity" light on the hard drive is constantly lit until the computer is hard reset. Strangely, I could use the the hard drive just fine with no visible problems other than when attempting to make another complete data backup (downloading/uploading files, even large ones, works fine). I've tried doing so on the "failing" drive itself and via a second drive that also has an OS installed on it. When the copy is attempted there, the same thing happens, and the second hard drive can't even finish shutting down the OS when it happens.

I assume the copy is failing when it finds the bad sectors on the drive. I've removed the drive and used my alternate one until I can find a solution. Is there any way to ignore or bypass bad sectors when copying? Any other ideas of what I can do? -- 143.85.169.18 (talk) 16:54, 5 February 2015 (UTC)

Microsoft ScanDisk is supposed to identify bad sectors, and mark them as unusable. You could try that. But, if new sectors are going bad all the time, it might be too late for that. StuRat (talk) 17:05, 5 February 2015 (UTC)

Should have mentioned that I've already ran CHKDSK (Windows 7), and that hasn't solved anything. I know the drive is beginning to fail, so what I'm wanting to do now is safely/reliably get my remaining data off the drive and trash it. -- 143.85.169.18 (talk) 19:27, 5 February 2015 (UTC)

The problem you have is exactly what ddrescue was built to address. -- Finlay McWalterᚠTalk 20:37, 5 February 2015 (UTC)

There are a number of tools' I use TestDisk but it does require some skill. --  Gadget850 ^talk 12:12, 7 February 2015 (UTC)

Are you sure? The description page you linked to suggest it is completely inappropriate for what the OP is trying to do, whatever the user's skill level. I don't see any discussion of imaging, nor handling bad sectors encounter during imaging. TestDisk may be useful after the OP has successfully image the disk, but that wasn't what the OP was asking about and since the OP is apparently trying to recover data off a physically damaged possibly dying HD, they want to image the disk and not fool around with it in situ.

BTW chkdsk/scandisk are also very bad ideas in a case like this. Yes they will mark try and move data from bad sectors elsewhere, and mark them as bad in the file system, but that's not what you want to do here. You don't want to be writing to the disk at all, and you don't want to be trying to hard to read the bad sectors initially.

Edit: [1] seems to confirm my view that TestDisk is likely a poor choice.

And I should perhaps clarify that in a few cases, it may be better to not image the disk. In particular if you're sure you only want to recover a small subset of files on the disk, it may be better to only try and copy those, rather than make a whole disk image given the risk the whole disk image (even with an advanced tool like ddrescue) could lead to further damage in the important parts before you successful image those parts containing the desired files.

However, even in that case, I'm not sure that TestDisk is normally necessary or helpful. To me, it sounds like it will only be helpful if the partition structure is actually damaged, which from the OPs description above may not be the case here. Even if the partition structure is damaged, I wonder if TestDisk is the best choice.

Ideally you want a tool like ddrescue which is designed to recognise damaged areas of the disk and preferably avoid reading them if there are files you are trying to recover in other areas which might not be damaged. I'm still not seeing any sign that TestDisk really has any understanding of physical damage on the disk, and how to deal with it. That said, I don't know of any particular tool that can deal with this. It's possible that ddrescue would work in cases when the partition structure is fine, but I'm not sure, it may only be useful for whole disk or part disk imaging rather than for dealing at the partition file level.

Nil Einne (talk) 14:09, 7 February 2015 (UTC)

February 6

window-7

I like to install window 7 in my laptop. how can I do. If i install window 7 with the help of installing disc will it automatically remove existing window 8.1 ramrash — Preceding unsigned comment added by Ramrash (talk • contribs) 02:24, 6 February 2015 (UTC)

It should give you the option during the install process either to install Windows 7 in addition to Windows 8.1 or format the disk, which will erase everything including any files you have not backed up, then install Windows 7 on the now blank hard drive. As far as the installation process itself, simply insert the cd into your computer during boot-up and make sure your computer is set to boot to the CD before the hard drive. This process varies depending on your BIOS, so if you still need help setting that up, please let us know what BIOS you are running. RegistryKey^(RegEdit) 15:36, 6 February 2015 (UTC)

Not quite that simple, as there will probably not be any available drive space so you will need to resize the partitions. And Windows 8 Fast Start can cause issues with Windows 7, so it needs to be disabled. I found a guide for this that looks pretty good: [2]. --  Gadget850 ^talk 11:57, 7 February 2015 (UTC)

Three-letter ISO 639-2 language codes supported by iPhone?

I've got information that iPhone 6 supports the use of Swiss German with the three-letter ISO 639-2 code gsw. I failed to verify this in iBabble-on or anywhere else, but still I'm sure that it's correct. Two questions:

1. Is there a public list of ISO 639-2 codes already supported by iOS, or that will be supported in the near future?
2. Does iOS anyway use ISO 639-2 only for those languages without an ISO 639-1 two-letter code? Or might a 639-2 be used also for languages with an existing 639-1 code?

--KnightMove (talk) 10:05, 6 February 2015 (UTC)

Addendum: The explanation might well be this code from iBabble-on linked above:

"NEW in Xcode 6 and iOS 8: You can now specify any regional dialect you wish, AND include languages that Apple has not yet localized. Your users will have to select the language from the new Language and Region settings in the Settings.app. Note that the language will display only for iOS 8 users. For users running previous versions of iOS, the system will actually ignore the localization folder completely for regional dialects like pt-PT and for languages like Farsi that have no system-wide localizations. Those users will see your app's default language."

What exactly does "ANY" language mean? Any language with an ISO 639-2 code? Any language with any version of ISO 639 code? --KnightMove (talk) 11:00, 6 February 2015 (UTC)

Consult the Localization and Internationalization guide for iOS, which explains how it works in detail. ISO 639-1 and 639-2 forms are accepted (Appendix B for details). Nimur (talk) 14:59, 6 February 2015 (UTC)

How I delete a value from a list of lists in python?

Imagine I have this

• A =Variable that is a list
• B and C =Lists that are inside list A
• X and Y = values inside list B
• Z and W = Values inside list C

How do I remove as some example, the value the second value of list C (so, the value w)?
PS: I want to remove an item by poiting an index array and not the value the item has.
Tried to find using google, but it talk only about lists (tried to come with something out of the examples but nothing worked) and not about lists of lists. 201.78.203.109 (talk) 18:30, 6 February 2015 (UTC)

>>> B = ['X', 'Y']
>>> C = ['Z', 'W']
>>> A = [B, C]
>>> A
[['X', 'Y'], ['Z', 'W']]
>>> del A[1][1]
>>> A
[['X', 'Y'], ['Z']]
>>> C
['Z']

-- Mr.Z-man 19:03, 6 February 2015 (UTC)

Haven't studied Python at all, but a quick Google search turned up this: In Python, how do I delete the Nth list item from a list of lists (column delete)? Hope it helps! RegistryKey^(RegEdit) 19:10, 6 February 2015 (UTC)

A[1].pop(1) — There may be some subtle difference in side-effects from Z's version. —Tamfang (talk) 05:56, 7 February 2015 (UTC)

Thanks Z man. Anyway thats exacly what I was doing but the program was saying 'List Index out of bounds', so I guess its a problem on the code and not on the way i made the deletion procedure.201.78.203.109 (talk) 10:48, 9 February 2015 (UTC)

Two hints: Python, like many modern programming languages, starts indexing at 0, so valid indices for a list of n elements are 0,...,n-1. Secondly, you can use "assert" in Python to check assumptions your code makes, and to make it fail noisily if its in an unexpected state. This is particularly useful to verify parameters of a function, or invariants of an object. --Stephan Schulz (talk) 16:07, 7 February 2015 (UTC)

Thanks, anyway I already found the problem and fixed it. Actually I did more than that, after founding the problem, I actually cleaned the code in a way there is no need delete an item of an list that is inside another list. 201.78.203.109 (talk) 10:48, 9 February 2015 (UTC)

What would happen if you deleted system32 folder on a windows computer

I know that is where all the kernel windows processes are. What if you deleted it? What would actually happen? — Preceding unsigned comment added by Radioactivemutant (talk • contribs) 19:59, 6 February 2015 (UTC)

Try it and you have your answer. Dat's ta way to learn : ¬ ) --Aspro (talk) 20:48, 6 February 2015 (UTC)

Oh. Back up everything first!--Aspro (talk) 20:51, 6 February 2015 (UTC)

Here's a youtube video showing what happens in XP [3]. SemanticMantis (talk) 21:08, 6 February 2015 (UTC)

If you loaded (say) XP into a VM. You can mess about with it, to your hearts content and keep rolling back... so you can do it again and again and again. Try this, using a Linux Mint pen-drive with a VM (sacrilege I know but a lot of fun). --Aspro (talk) 22:44, 6 February 2015 (UTC)

Forgive me for being grumpy (!) but our OP is very mistaken! Processes are not the same as files - especially not on Windows! Hopefully we can correct this conceptual misunderstanding so they can develop a more full understanding of how this all works.

When you delete (or try to delete) system files, you remove them from the file system. Tongue twister though that is, it is conceptually very different from killing the processes that they represent. This is, for example, why it is possible on certain types of *nix-like systems to hot-swap the kernel - you can (in concept) replace the file on disk, re-load it into RAM, and then jump into it. In practice - a real operating system like Windows or Linux throws in a ton of extra "gotchas." Files may embody dynamic library data or page files. It is not easy to determine when the system will load that data from disk, or commit back to disk: it may not be possible to safely operate the system while simultaneously modifying these files. Systems like Windows therefore forbid the file manager from (easily) modifying these important files. Unless there is a reason to engineer this type of behavior and ensure that it is functional, the system may behave in "an unspecified fashion."

Whether the important files live in system32 or in any other location is moot; but the key thing to know is that the system software has expectations about what it can safely assume is on disk (or otherwise in persistent storage). If you (the user) intentionally violate these assumptions, the system will break. Because Windows is not free software, it is difficult for a hobbyist to study how these behaviors work with very much detail. However, there is a wide community of researchers who are interested in systems that can self-modify their system-software at runtime. For example, ksplice is linux technology that allows Linux to modify its own kernel at runtime. I even once worked on a system that could modify its own CPU architecture at runtime - it was fascinatingly complicated! So if you are interested in studying this kind of behavior, there are better environments than Windows. Windows is designed and sold as an operating system for ordinary application-users, so it's not great for system-level software experimentation of this sort. Nimur (talk) 00:43, 7 February 2015 (UTC)

Mistaken? That is why our OP asked the question! However, having said that, me thinks you gave a very good and informative reply.--Aspro (talk) 15:07, 7 February 2015 (UTC)

February 7

Looking for a blog post

Hi, I'm looking for a fairly recent blog post. The author was looking at how to reduce (sum, or maybe count occurrences) an array quickly. I think this was specifically on a single core of a modern Intel CPU - i.e. looking at microarchitectural influences, rather than throwing relatively coarse parallelism at the problem. I do remember a specific trick used was to keep multiple copies of the reduction variable, because even on a single thread it allowed the scheduler to make better use of ILP in an unrolled loop (or similar). Does anyone have a link to the post I'm thinking of? Thanks. 82.13.241.56 (talk) 03:26, 7 February 2015 (UTC)

Qatar IP addresses

Does Qatar have "normal" IP addresses yet? MediaWiki:Blockiptext still mentions only Special:Contributions/82.148.96.68 and Special:Contributions/82.148.96.69, but both of them have been inactive for several years now. Nyttend (talk) 14:29, 7 February 2015 (UTC)

Could a virus written in Java run everywhere?

That's what Sun Microsystems says "write once, run everywhere."--Noopolo (talk) 20:14, 7 February 2015 (UTC)

It wouldn't run if the Java runtime had never been installed on the computer. I'm not enough of an expert to know if there might be a version of the Java runtime hidden away someplace where it wouldn't be obvious by browsing the add/remove program list provided by the operating system. Jc3s5h (talk) 20:18, 7 February 2015 (UTC)

I believe it could. It would be reminiscent of a Microsoft Word macro virus that infected Windows and Mac versions of Word alike. —Steve Summit (talk) 23:14, 7 February 2015 (UTC)

"Everywhere" is a slight exaggeration, but a Java bytecode can run in a surprising number of places.

However, while the possibility of Java viruses was proven way back in the 90s. (See Strange Brew (computer virus)), They're rare, and I'm not aware of one that can jump platforms.

Most situations where Java is used are sandboxed pretty heavily. Also, the logic needed to find and then infect an Android program would be very different than the logic needed to find and infect a desktop java app. An app that could jump platforms like that would need to be very sophisticated. APL (talk) 23:19, 8 February 2015 (UTC)

(Fixed your link syntax) Good point on platform jumping. Also Windows still has by far the highest install numbers for desktops according to Usage_share_of_operating_systems, so why would a malicious virus-maker bother going through the extra effort? SemanticMantis (talk) 14:33, 9 February 2015 (UTC)

February 8

Git repository question

I've started taking a class for which my teacher has set up a Git repository. On the first day of class, I accidentally made a commit to the master. I'd like to fix my error by going back to the last edit before my commit (which would therefore be my teacher's last commit before class started) and then do a pull from that point. I'm thinking this would pull in all of his changes since the beginning of class and stop giving me errors about conflicting commits. Will this work as I want it to and how do I do that? Thanks, Dismas|^(talk) 11:37, 8 February 2015 (UTC)

I'm assuming you've committed to your local master, but not pushed the changes to the repository? If so, git reset --hard origin/master will reset your local repo to the remote origin.--Phil Holmes (talk) 11:56, 8 February 2015 (UTC)

Yes, I had not done a push. So, I tried what you gave me. I got "HEAD is now at XXXXX [ed: where XXXXX is a number] Updated Copy_Into to use a clearer formulation of the loop." Then I tried "git pull" and it told me I was up to date which I was not getting before. So, I think I'm all set. Thanks! Dismas|^(talk) 12:01, 8 February 2015 (UTC)

Resolved

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 A8v (talk • contribs) 12:38, 8 February 2015 (UTC)

Google Translate:Hello, Firefox stop playing video live globovision.com All I see is a black window and despite saying "playing" is not seen nothing. Anyone know how to fix this? Rojomoke (talk) 13:32, 8 February 2015 (UTC)

Try a reboot ? StuRat (talk) 16:35, 8 February 2015 (UTC)

Gmail account (almost) broken

I have a gmail account and can sign on and view my inbox. I can also switch to my (nearly empty) spam folder. However, I am unable to send messages or switch to my Trash folder. In the first case, a box shows up at the top of the screen saying "Sending" and in the second, saying "Loading," but nothing ever happens beyond that. The account had been working fine for several years. I normally use Chrome, but ran one test on IE just in case that made a difference, and it did not. More testing: using a different gmail account on the same computer works fine and using the broken gmail account on a different computer, also with Chrome, also works fine. Also, logging onto a different Windows account on the same computer, everything works. So if there are no better ideas, I can rebuild the computer account, but I'd rather not if there is an alternative. Ma^t_chups 15:07, 8 February 2015 (UTC)

Are you using Gmail via web brower, POP3 oder IMAP? --Hans Haase (有问题吗) 15:11, 8 February 2015 (UTC)

Via web browser, in all of the tests.Ma^t_chups 15:20, 8 February 2015 (UTC)

Weird behavior from updating to Notepad++

I just updated to Notepad++ 6.7.4 (I think), and when I relaunched it "Freedom of expression is like the air we breathe, we don't feel it" started to get typed in a new tab. Is this normal or is this a virus? — Melab±1 ☎ 18:17, 8 February 2015 (UTC)

No worries. This is the Je suis Charlie edition.[4] --  Gadget850 ^talk 18:23, 8 February 2015 (UTC)

This is not a computer virus (it does not meet the definition); but I would certainly call it malware or even a trojan horse (software) - software that maliciously steals your user-interface without your approval, that was installed alongside a "useful" software application. The author of Notepad++ has created this malware on purpose to spread a political message.

Notepad++ is GPLed free software. You can download source and modify it if you wish to remove this undesired behavior. Or you can just grab the 6.7.3 version, which did not include this malware-like behavior. Keep the source handy: you may want it in case you need to modify it in the future! Alternately, you may diff source between 6.7.3 and 6.7.4 to study how to write malware that steals control of a user's interface on a popular operating system. It appears that this is the only change!

Whether we agree or disagree with any specific political messages about "freedom", it is generally accepted that good software does not take control of your computer in an undesireable way. This is even more true of free software - it is in fact a core tenet of the free software ideology: as Richard Stallman has repeatedly emphasized, freedom means you have control over your software, not the other way around. I think it's incredibly ironic that the author has released GPLed software that intentionally, literally, visually takes control of your computer to write a message about how important freedom is. Contrast this to a different text editor, say, vim - which has included an unobtrusive political message for many years - uganda.txt. At no time does vim try to steal your terminal and force you to read this message. If you disagree with the contents of that text file, you can ignore that file or even delete it. It will never pop up on your screen and start "typing itself out." You may find that vim has many other advantages over Notepad++, but that is a topic for another time.

Nimur (talk) 05:49, 9 February 2015 (UTC)

More info: http://notepad-plus-plus.org/news/hacking-npp-site.html --  Gadget850 ^talk 11:43, 9 February 2015 (UTC)

Private email (sounds like an oxymoron)

How can I get a private email? I have gmail right now, but feel uncomfortable knowing that Larry Page and Sergey Brim are reading my emails. The problem is specially Sergey, since Larry does not appear to be much of a talker.

Should I create my own mail server or what?--Senteni (talk) 19:02, 8 February 2015 (UTC)

Among the things you will need are an IMAP server, an SMTP server, and a registered domain name with an MX record. In principle, all of these can point to the same machine, which could even be your personal computer. You'll also need to spend a lot of time administering the server to keep spam out (which is pretty easy nowadays); and also to ensure that your outbound mails don't get blacklisted by popular spam filtering software (which is much harder). Many popular email services will blacklist mail that you send as "spam" anyway - simply because they choose to blacklist any anonymous SMTP server - and there is nothing you can do to stop them. Nimur (talk) 19:46, 8 February 2015 (UTC)

So, basically, creating an email server is a lot of work, right? But what if I buy a hosting plan that includes my own email, can that be private towards the hosting company? Or is this the same problem as gmail, but maybe worse, since I would be trusting a less well-known company, that has less eyes upon it?

What do people who need a certain amount of privacy do? For example, lawyers, accountants and the like? How to establish a safe communication channel with clients? Senteni (talk) 21:29, 8 February 2015 (UTC)

Email encryption --Aspro (talk) 21:55, 8 February 2015 (UTC)

If you want to set up your own email server, Ars Technica did a good multi-part series on how. [5] [6] [7] [8]

When you buy a domain name, it often includes an email account, but it's generally not hosted on your server. There are companies that specialize in email accounts to meet specific privacy requirements, like HIPPA requirements for doctors in the US. See [9]. Gmail can be HIPPA compliant if you use Google Apps (which means you need your own domain and need to pay Google) and you fill out some extra forms. But even without the extra forms, paid Google Apps doesn't have ads in Gmail, so it's more "private" than a regular free Gmail account. If you just Google "secure email" you can find other companies like Hushmail. The problem with using a smaller company is that it's harder to tell how legit they are and there might be a higher risk of downtime depending on their support levels and how many locations they have servers. Mr.Z-man 21:58, 8 February 2015 (UTC)

Aspro is right. The only way to have truly "private" email is through end-to-end strong encryption.

Even if you own your own server and keep it in your basement guarded by dragons, your emails will still be vulnerable because they have to be transmitted through at least one or two intermediary steps before reaching the other party's email server. (Which, in this day and age, is probably gmail.com anyway!)

In theory, anybody who operates those intermediary points on the network could be reading your email. The email system has evolved from a system invented in the early 70s when people didn't worry as much about computer security, because there just weren't that many people on the net. APL (talk) 23:26, 8 February 2015 (UTC)

In theory, the post office still works, and is relatively secure, at least as far as message content goes. You'll need to waste paper, buy a stamp, reveal some physical addresses and wait a while, but freedom isn't free. Google is temptingly so. But paper comes with a flammability feature, at no extra charge. InedibleHulk (talk) 23:35, February 8, 2015 (UTC)

Encryption will protect the content, but there's still the issue of snoops knowing everyone you email and everyone who emails you. I suppose you could have your email forwarded several times to make it a bit more difficult to track, but certainly not impossible. StuRat (talk) 06:19, 9 February 2015 (UTC)

"Europe won’t save you: Why e-mail is probably safer in the US" is an article that's over a year old and certainly outdated in places (the Posteo is now in English as well as German) but is still of interest. -- Hoary (talk) 10:33, 10 February 2015 (UTC)

How can I find out what's taking up all the space on this computer?

My friend has a Windows 8 HP laptop, it holds 21.5 GB of memory. That's really freaking small, I know, but I can't even figure out why it only has like 300MB of free space left. It looks brand new, no videos, no music, no documents, she seems to have installed Steam but there are no games installed (she mentioned hoping to install The Sims 3 but didn't have enough space; that's why she asked me to free up some space).

Is it normal for the laptop to be almost entirely full before she's even installed anything? How can I free up space? 50.54.55.153 (talk) 22:43, 8 February 2015 (UTC)

That is a pretty small drive by today's standards. Is it SSD? Is it the only drive? WinDirStat may be of help. --  Gadget850 ^talk 23:09, 8 February 2015 (UTC)

It's probably one of HP's mini laptops, or tablet/laptop hybrids. They're mostly designed to be iPad competitors for web-browsing and email and such, and have very little storage.

this one for example, has only 32GB. Which after a windows install is probably very little. APL (talk) 23:39, 8 February 2015 (UTC)

If by memory you mean HDD, then 21 GB for a Windows installation is not much. It's your HDD which is way too small. --Noopolo (talk) 23:23, 8 February 2015 (UTC)

According to Microsoft, 64-bit Windows 8 requires 20 GB of hard dive space. It sounds more like a netbook than a full-featured laptop. Mr.Z-man 23:32, 8 February 2015 (UTC)

It's possible that steam partially downloaded The Sims 3. So your computer has a bunch of Sims3 installation files filling up it's very tiny hard-drive. Try right-clicking on The Sims in Steam and deleting local files. See if that gives you back some space.

You could probably expand the thing's storage capacity a bit by installing the largest SD card you can find, if it has a slot for one. You could then configure steam to download games onto that card. But, ...really, if they've given it that little space, don't get your hopes up for Sims 3. It probably won't run very well. APL (talk) 23:39, 8 February 2015 (UTC)

Is it possible that your disk partition only contains a portion of the total disk space ? StuRat (talk) 06:23, 9 February 2015 (UTC)

To clarify, if you see something like "Hard Disk (C:) 21.5GB" inside My Computer (or "Computer" as it's called in Windows 7 and later), that's the partition size. If you see "Hard Disk 0 21.5GB" inside Disk Management, that's the size of the physical HDD, the drive itself. If it's substantially more than that (say, 37.5GB or more), there will be either

• a big empty space where you can make another partition and move stuff there,
• or expand the partition using a utility like gParted (backup first!)

or

• a partition without a drive letter. In the latter case, you can right-click and "assign a drive letter".

Other things you can try, even if your physical HDD size is 21.5GB:

• Search C: for large files. Some programs have their own TEMP folders, and there can be huge files left. You should check the "show hidden files" option, and/or uncheck the "hide system files" option first.
• Chkdsk the partition for errors. Some errors occupy much space, too. (This has become rare in NTFS but it can happen.)
• Reset the System Restore (make a backup first). Steam and other services handling huge EXE files can add up. (Basically, System Restore makes an in-partition backup of all EXE and DLL files, which doesn't mix well with Steam.)

- ¡Ouch! (^{hurt me} / _{more pain}) 09:14, 9 February 2015 (UTC)

Downgrading to Windows 7 or XP might be the way to go if you're stuck with 21GB; these OSes are smaller and have most features of 8.1; in fact, many find the new features of 8 / 8.1 undesirable. XP would run great on the machine if you can get the drivers, and 7 would run quite well, too. - ¡Ouch! (^{hurt me} / _{more pain}) 10:57, 9 February 2015 (UTC)

XP is an unsupported OS and is a dumb idea for an internet connected computer. 7 install size isn't much smaller than 8.1. Further for such a low speced computer, it could easily have only 1GB of RAM. Running Windows 7 on 1GB RAM isn't a fun experience. 8.1 is not excellent but it's a fair amount better. Even if it has 2GB, the CPU is probably somewhat low speced and likewise the GPU. Again 8.1 will give a fair better user experience with such a low speced computer (it's clearly designed with 8/8.1 in mind, particularly if it has 2GB RAM but such low sized storage). Probably the first thing to do would be to see if the computer has a microSD slot. I suspect it does considering how small the eMMC apparently is (and with such a small size, I'm sure it's an eMMC if it's in the past 2 or 3 years). In that case, considering adding a 32GB or mpre microSD card if you need more space. Note that although you may think running stuff on an SDcard will be slow, remember that eMMCs aren't necessarily better. (In fact, I suspect even a UHS-I card or may be even a class 10 will often be theoretically faster. Theoretically because although the card may be faster, it doesn't mean the system is capable of accessing it at that speed.) Alternatively look for a non Windows OS (may be not a simple option if you want Sims 3) or wait until Windows 10 (Windows 10 will have a method to reduce OS disk space usage). I'm not convinced Sims 3 is going to be fun to play on that computer, but if it is, your best bet is probably sticking with 8.1 and getting it working there. Nil Einne (talk) 12:08, 9 February 2015 (UTC)

XP is a security hole. Advising a different OS for a relatively new system is not the best option.

Checking my lab system

, the install sizes for Windows with updates an no other apps:

• Windows 7 Professional x64: 18.2G
• Windows 8 Professional x64: 18.8G
• Windows 8.1 Professional x64: 14.3G
• Windows 710 Technical Preview x64: 25.7G

We need feedback from the OP. --  Gadget850 ^talk 12:45, 9 February 2015 (UTC)

XP Professional: 2.3G ¡Pwned! (^{hurt me} / _{more pain}) 06:54, 10 February 2015 (UTC)

(although that's without the post-SP3 updates; it's not meant for internet anyway, so only useful for single/LAN play and not for Steam)

Crunchbang Linux, for example, would be inside 5GB. -- Hoary (talk) 10:41, 10 February 2015 (UTC)

February 9

best version Linux for a beginner, installing programs

I've been thinking of migrating from Windows to Linux for years, and have played around a bit w Ubuntu and Fedora, but still find it rather inaccessible. I have no Unix background, and often can't figure out how to install a program. (Or to get the OS to recognize it once it is installed.) Any advice for a version of Linux that's intuitive to someone who isn't a programmer and doesn't know Linux? — kwami (talk) 03:15, 9 February 2015 (UTC)

Ubuntu is already amongst the easiest to use, unfortunately. The only one that might be more friendly is Linux Mint. You don't really need to know programming to use Linux, it just opens a lot of doors. However, is there a reason why you can't just learn a flavor? --Wirbelwind(ヴィルヴェルヴィント) 03:28, 9 February 2015 (UTC)

Well, when I'm using an "easy" flavour, and install a program, and the OS doesn't recognize it as a program, and a friend of mine who's used Unix and Linux for decades can't figure out what the problem is, then it would seem there's a rather steep learning curve. I'd like it if I could install programs without line commands, as in Windows. (There are plenty of reasons to not like Windows, but at least installation's straightforward.) Thanks for the suggestion of Mint, though. I'm thinking of making my laptop dual-boot to wean myself off Windows. — kwami (talk) 03:57, 9 February 2015 (UTC)

Unetbootin is your tool. You can make a dual-boot from that, relatively pain-free, but make sure you have a partition set up to install on, otherwise it'll be bye bye Windows and files forever. Unetbootin will allow you to download and install any flavour on your partition. You can even run it from a pen drive, without installation, and any files you make can be saved on the hard-drive or pen drive - it's your choice. I use it all the time. KägeTorä - (^影_虎) (Chin Wag) 14:40, 9 February 2015 (UTC)

The main difference between installing programs on Linux vs Windows is that Linux uses a package manager rather than a standalone installer for each program. Our article has a table explaining the differences. You shouldn't have to use any command line tools to install a program - the popular distros should all include a GUI tool for their package manager, like Ubuntu Software Center. You can use that to browse and install most common programs that are available through the OS's software repository. There's also Steam for games (install Steam through Software Center, then install games through Steam).

For programs downloaded from websites, if they're Linux-friendly, they'll usually include a .deb (Ubuntu and variants) or .rpm (Fedora) download option and when you run that file it should open in the GUI for the package manager to install it. [10] goes over how to install Google Chrome this way.

This article covers all the ways to install software on Linux roughly in order from most to least common for most people. Pretty much the only time you should ever have to use a command line to install a program is if you're compiling it from the source code, which you should rarely have to do.

Most common distros are all based on 2 or 3 "base" distros all based on the Linux kernel, so "under the hood", they're pretty similar. The main differences will be in the user interface/desktop environment. Personally, I found Ubuntu's Unity to be somewhat frustrating (and glacially slow on my old laptop), so I switched to Xubuntu, which is just Ubuntu with the Xfce desktop. We have an article on Comparison of X Window System desktop environments, which is a good starting point. Since it's the same OS underneath, it's possible to switch desktop environments without reinstalling everything, but it can be somewhat complicated. So I would suggest picking an environment you like, then finding a distro that uses it. Mr.Z-man 14:56, 9 February 2015 (UTC)

Thanks for all the tips and links. They make it seem less daunting. Mint or Xubuntu look promising.

Yes, the desktop is a separate issue. I think maybe I'd like to try something rather different from Windows, so I can see what the advantages are.

• You could try reading Linux is Not Windows to be able to look at things with a new unclouded mind. Then load Mint onto a pen-drive [11] and have a little play around -without having to compromise you exiting windows installation. Enjoy. If windows was released for the first time to-day it would not stand a chance compared to Mint et al. Linux distros have evolved and is now easier to use maintain than window -but trying is believing. Linux Mint also has a forum where they love to advice to newbies .[12]--Aspro (talk) 20:00, 9 February 2015 (UTC)

• If you look around the Mint website you'll see mentions of something called Mint LMDE that make it sound rather scary. It isn't so at all, or I haven't found it so. It's Mint based on Debian rather than Ubuntu and for installation, deinstallation and upgrading of programs uses Synaptic, which is very easy. (Whether it's standard Mint or LMDE, the default color scheme is hideous IMHO; but changing it takes mere seconds, so no matter.) Actually I'm now typing this not via LMDE but via Crunchbang Linux (also based on Debian), whose website makes it sound even more scary than LMDE; it isn't, and the people on its message forums are unusually helpful even by Linux standards. I use LMDE on my newest computer as this computer has more oomph and also because the regular installation of LMDE comes with drivers I needed for wireless, drivers that didn't/don't come with Crunchbang (and I was too lazy to read up on how to get and install them). If you have an older computer, or are feeling a little brave, you might try Crunchbang. -- Hoary (talk) 09:50, 10 February 2015 (UTC)

The best answers have probably already been given, but another idea is to use something that has a good, understand and forgiving community that can help you through any problems. The Raspberry Pi is designed to introduce children and beginners to programming and Linux, and has a community very welcoming of noobs. You can either get yourself a Pi board (~$35 plus tax) and play around to your heart's content without fear of breaking anything, or you can use Debian Wheezy on your current machine. The Pi's operating system Raspbian is functionally identical to Debian, so any advice from Pi forums such as http://www.raspberrypi.org/forums/ will be applicable. - Cucumber Mike (talk) 10:09, 10 February 2015 (UTC)

Citation software

Are there any citation software, such as endnote or refworks, which will automatically create a citation if you enter a DOI? 194.66.246.99 (talk) 10:47, 9 February 2015 (UTC)

User:Citation bot is software than can do exactly this: convert a DOI into a full, standard-form citation. Its source code used to be available on the Wikimedia ToolsLab server, but the page is down. Perhaps if you contact the developers, they can help you set up a version that does not require a MediaWiki server. Nimur (talk) 15:42, 9 February 2015 (UTC)

Crossref.org [13] will take a DOI into a form, then if you click "actions" you can export as BibTex, RIS, and raw text in many citation formats (IEEE, Harvard, APA). This is fine for any small project, but might not be suited to large batch processing. SemanticMantis (talk) 17:37, 9 February 2015 (UTC)

Disk Space on Macbook Pro

Inspired by a question above, I am using a brand new Macbook Pro (with Yosemite installed). For some reason I do not have any disk space left to download Apps, and I am wondering why. I have an account on iCloud, but that seems to make no difference. How can I find out what is taking up all this valuable space? For such an expensive laptop, it ought to be usable, at least. KägeTorä - (^影_虎) (Chin Wag) 11:05, 9 February 2015 (UTC)

On the face of it, that seems very implausible, unless you've transferred a lot of media. I think the smallest MacBook now comes with 256GB SSD, and that should leave you plenty for apps - I have all kinds of crap (including a large music collection, a complete UNIX tool layer, and several movies and TV shows), and need less that the 256 GB. Can you select "Macintosh HD" and hit Command-I to get capacity and available space? I usually use the commandline and du (Unix) to find out where space goes (the -h option is useful!). --Stephan Schulz (talk) 11:21, 9 February 2015 (UTC)

You could also go to the Apple menu and select "About this Mac" and click on the Storage tab. Dismas|^(talk) 11:53, 9 February 2015 (UTC)

One lives and learns! Thanks! --Stephan Schulz (talk) 11:56, 9 February 2015 (UTC)

Thanks. Capacity is 120.11 GB, and Available is 6.2 GB. Used is 113.91 GB. I have Parallels installed, along with Windows 10 on this virtual hard drive. Could that be the problem? KägeTorä - (^影_虎) (Chin Wag) 11:32, 9 February 2015 (UTC) [Post bizarrely reverted by User:David Biddulph, who does not even appear to be in this conversation.] KägeTorä - (^影_虎) (Chin Wag) 14:48, 9 February 2015 (UTC)

Apparently OS-X Yosemite fits into 8GB for a basic install, or 16 for a generous one [14]. You seem to have a 128GB SSD (sorry, I did not know that still existed). So some 80-100GB seem to go somewhere else. I don't know how Parallels handles things, but many virtualisation solutions simulate a fixed-size disk, and reserve the full memory. Are you sure about Windows 10? It's only available as a preview, as far as I know - 8.1 is the released version. Windows alone will take up 13 GB for the 64-bit version, so that is a generous chunk. ---Stephan Schulz (talk) 15:04, 9 February 2015 (UTC)

Yep, a huge "virtual disk" is probably allocated for Windows and OSX sees it as "full" even though it probably isn't. Win 8.1 can apparently take up ~27 gigs by itself, though there are some ways to trim it down [15]. Here are some instruction to reclaim space from the windows virtual disk in Parallels [16]. SemanticMantis (talk) 17:29, 9 February 2015 (UTC)

I use the terminal command, du -h -d 3 / to produce a human-readable summary of my disk use, three folders deep, starting at the filesystem root. (This may require a long time and/or administrator permission). Another common place to look is ~ (your home directory). Massive amounts of content can accumulate in ~/Application Support, ~/Library/Logs, ~/Library/Developer/ ... and other folders in your home directory. If you find something large and don't know if it's safe to remove (or even what it is), just let us know.

The official out of disk space support is a helpful reference. It also suggests the culprit might be your email... I've seen mailbox caches that can be hundreds of gigabytes.

Nimur (talk) 15:52, 9 February 2015 (UTC)

Help recovering a crashed hard disk (stuck at ntldr is missing)

Hello. I'm hoping someone here can help me in recovering my crashed hard disk. Here's what happened:

1. My laptop fell from my office table
2. It would boot but shut down automatically within a minute
3. Went to a repair shop, had to get the graphics card replaced (apparently it wasn't working after heating up)
4. After this, the windows wouldn't boot
5. The repair shop didn't gaurantee recovery of data or windows (original)
6. Since I no longer have the windows product key (it was only on the back of the laptop and got erased) and never got a Windows Installation disk with the laptop in the first place, I got a new hard disk installed and got the old one a SATA to USB converter case to fix the thing myself
7. Tried simply plugging in the hdd as an external hard disk, only one partition showed up, and it wouldn't eject, so had to unplug it
8. Subsequent attempts at accessing it as an external hard disk got me the message that the drives needed to be formatted before they could be used
9. Then I tried windows Repair command line bootrec.exe with /fixmbr, which worked fine
10. Then I tried bootsect.exe /nt60 all /force and got the error Could not open the volume root directory. The parameter is incorrect.
11. Then I tried bootrec.exe with /rebuildbcd to get Total identified windows installations: 0
12. Then I tried GetDataBack free version which told me after showing me the contents of a partition that it wouldn't recover the partition unless I bought a license
13. Then I tried testdisk which showed all partitions except one (which might have been the partition I tried to recover using GetDataBack) and showed that the dellutility partition formatted as Fat16 and of 203miB size was bootable while the actual c drive (232giB) was only primary. Since it wasn't showing one partition, I didn't write the partition table using it.
14. Trying to boot from the hard disk showed a Missing Operating System message.
15. Today I tried diskpart and marked the actual c drive as active. Diskpart was showing a fake 242giB extended partition entry though. Disk management was showing some partitions, but I didn't look at it closely.
16. Then when I tried to boot from the disk, it showed the message Ntldr is missing. Press Ctrl + Alt + Del to restart.
17. Disk management now shows the entire hard disk as unallocated. Diskpart can no longer find any partitions.

Here are my questions:

1. Is the partition table actually gone or is it just that windows can't recognise it?
2. Does "ntldr is missing" mean windows (in some form, whether fine or damaged) is present?
3. Is it possible to repair windows without a repair disk (I can make a usb flash drive but the optical disk reader is broken)
4. If I create a bootable flash drive with windows on it and set the boot priority to usb mass storage, will it try to boot from the external hdd or the flash drive? Or go straight from the external hdd to the internal hdd?
5. If I do make a windows usb flash drive and boot from it, will it be able to repair windows on an external hard disk or will it just look at the internal one?

I hope that the windows is present and just needs to be repaired, and that repairing it will be possible without having to physically open up my laptop and reinsert it as the internal hdd.

Also, the laptop is the only computer I have right now, so I have to note down/print any methods I need to try before actually trying them.

It would be a huge help if someone can help me out in fixing this.

Best Regards --117.234.152.207 (talk) 14:59, 9 February 2015 (UTC)

I think your HDD is physically damaged. It is impossible to say whether the data can be recovered. You should find a specialized firm (repair shop) that can attempt such a recovery. Ruslik_Zero 20:18, 9 February 2015 (UTC)

@Ruslik0:: First off, thanks for responding.

I doubt if there's been any significant physical damage because GetDataBack free version showed me the contents of a 100giB partition, and TestDisk while reading the disk only got an error at one sector.

And I did go to several specialized repair shop, but the price the guys are asking is more than the cost of a new hdd. To top that, they're guaranteeing that windows will be lost, the entire hdd will be formatted, and then whatever data retrieval is possible will be done. This obviously doesn't inspire much confidence and is why I'm trying the fixing myself.

Also, since asking this question, I've tried accessing the drive using WinHex (free version). It shows my C drive correctly marked as a bootable partition. Sector 63 looks ok. However, sector 64 is missing the bootloader, and WinHex was unable to detect the other partitions (I didn't try the option to recover the partitions).

At this point, I'm thinking about creating a disk image of the entire disk (on a larger external hdd) so as to minimize data loss, then mount the disk image virtually and try to extract the data.

Could you (or anyone else reading this) recommend a FOSS software for creating a disk image for later data retrieval?

Also, answers to the perplexing questions 4 and 5 above would be highly appreciated.

Best Regards--117.225.80.204 (talk) 13:35, 10 February 2015 (UTC)

Do not turn off or unplug your computer

Whenever I'm installing a Windows update, I see the usual message of "Do not turn off or unplug your computer". Makes sense: it's updating basic system files, and turning off the computer could cause chaos. But why is unplugging it a problem? I'm using a laptop with a fully charged battery that runs for several hours. Why would there be a problem if I decided to run the update on battery power? Or is this just meant to cover people who would otherwise unplug their desktop or who have laptops with insufficient battery power? Nyttend (talk) 19:01, 9 February 2015 (UTC)

It screws up the update installation when it hibernates. My mum did that with her computer after I did factory reset and so I had to do a system restore to fix it as it kept restarting and wouldn't properly bit the OS. Sir William Matthew Flinders Petrie | ^{Say Shalom!} 20 Shevat 5775 19:04, 9 February 2015 (UTC)

Some installs can take hours. Even if you prevent the laptop from sleep/hibernate, you don't want to leave a laptop unplugged and unattended whilst mucking with the OS. Also consider that while the installer can probably technically somehow check to see if the computer is a laptop, it's easiest to just have the same instructions for installing on any box. SemanticMantis (talk) 19:44, 9 February 2015 (UTC)

Yes the same message shows on computers without battery power. Note however Windows nowadays is intentionally robust (as with most OSes). While you shouldn't kill the power during updates, in reality what will most likely happen is it will rollback updates when you turn the power back on and everything will likely work fine. This doesn't of course precluse things going wrong occasionally. Nil Einne (talk) 21:05, 9 February 2015 (UTC)

I had a laptop that was a few years old that I used as a media center connected to my television, the battery would charge to 100% and last precisely about 90 seconds if I ever unplugged the power. Vespine (talk) 21:46, 9 February 2015 (UTC)

Either this, or it's all a conspiracy by Big Computa to let them download your hard drive contents, hack your webcam, and run up your Big Electra bill. μηδείς (talk) 22:02, 9 February 2015 (UTC)

I've hibernated laptops on several occasions during a Windows update, and it has continued quite happily on resume. The problem occurs if power fails before hibernation, or if the computer is only sleeping (with data in RAM) and the power fails, but Windows usually just does a rollback in these circumstances (as Nil Einne explains above). The laptop I am using at present is like Vespine's and it would be foolish to try to run an update on a weak battery, but usually there is no problem with a good battery, especially if your system is set to perform a controlled hibernation when the battery reaches 10% power. (Disclaimer: I offer no guarantee, just an observation based on experience. ) Dbfirs 22:43, 9 February 2015 (UTC)