Wikipedia:Reference desk/Archives/Computing/2013 February 24

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February 24[edit]

Wikipedia via text.[edit]

Hello

Would you please let me know when "Wikipedia via text" service is going to be availed in India and from when?

And please shed a little light on details on how the article is “delivered”.

Is the plan to send them the entire article, broken up into 160-character chunks? Pre-iPhone, I remember having motorola and nokia phones whose SMS clients made you back out of each message in your SMS inbox to read the next one, so if someone sent you a text while you were reading the current one, you had to hit back, down, center to read the next one.

So imagine doing that about a million times for each article.


Regards Bhushan — Preceding unsigned comment added by 116.202.5.87 (talk) 06:33, 24 February 2013 (UTC)[reply]

You might be better asking on the Village Pump, technical section for questions about Wikipedia (and mediawiki software that it runs on).
For the second part of your question, SMS have a 160 character limit (if in US-English, 140 in other European languages, and less in non-Latin languages), however most mobile phones will send larger messages as multiple texts, and the receiving phone will reassemble them back into one message for display. CS Miller (talk) 17:05, 24 February 2013 (UTC)[reply]
For the moment, if your mobile-phone is WAP capable, you can access Wikipedia via WAP on http://wapedia.mobi/; it will split articles into smaller WAP pages. This site is provided by a third-party, our page about their service is Wapedia. Or if you have a smart-phone then there is our mobile page, http://en.m.wikipedia. There are other access methods listed on Wikipedia:Mobile_access. Both these main services are read-only, and don't provided direct links to the talk: pages. CS Miller (talk) 17:14, 24 February 2013 (UTC)[reply]
Considering this is basically related to the Wikipedia Zero project [1] and there are still no wikipedia zero partners in India [2] I don't know if I'd get my hopes up about it coming to India any time soon. It's true this system would probably cost less for the telco to run then providing access to wikipedia for free via the telco's data network but I'm not sure this is the primary reason it has not been offered yet. Nil Einne (talk) 04:29, 27 February 2013 (UTC)[reply]

Default browsers[edit]

I am using Win7 with Windows Live Mail and Dropbox (service). I prefer IE9 as my browser. When I click a hotlink in an email or 'goto website' in Dropbox they open Google Chrome though. I have looked everywhere to change these to IE9 though. Are they in an .ini or .cfg file somewhere? I hate messing with those.--Canoe1967 (talk) 15:56, 24 February 2013 (UTC)[reply]

See http://windows.microsoft.com/en-US/internet-explorer/make-ie-default-browser#ie=ie-9. PrimeHunter (talk) 16:22, 24 February 2013 (UTC)[reply]
That almost worked until I re-booted and Google took over again. I finally found it in control panel from the Windows start menu. I couldn't untick Google as defaults but when I ticked IE9 boxes it removed the ticks from the Google boxes. Couldn't be done from within the browsers it seems.--Canoe1967 (talk) 19:56, 24 February 2013 (UTC)[reply]

File[edit]

Physically, what is a file? If you save a file on your computer, how is that reflected in physical terms? 203.112.82.1 (talk) 16:52, 24 February 2013 (UTC)[reply]

It is saved in binary in memory. Groups of 'mark, no mark'. Most hard drives have some fragmentation so many files are stored in pieces and kept track of with file allocation sections of the memory. They are also marked with other data such as file type, date, access, security, etc.--Canoe1967 (talk) 17:06, 24 February 2013 (UTC)[reply]
"Memory" normally refers to the temporary storage space on a computer (RAM). A file is there until it is saved, at which point it is copied to the hard disk, flash drive, CD, DVD, etc. When you "read a file" or start a program, this copies it from the hard disk (or other permanent storage media) into RAM (except for some large file, where only a portion is kept in RAM at a time). StuRat (talk) 17:08, 24 February 2013 (UTC)[reply]
(ec) There are lots of bits set for the file itself. Normally these will all be in a row somewhere on the hard disk, but, due to file fragmentation, it may be necessary to break the file up into different physical segments of bits on the hard drive. Since the hard drive doesn't allow you to have just one bit here and a couple there, you end up with one disk sector here, and a couple there, instead.
Then there's an index stored elsewhere on the disk which makes it all work. This lists some basic info on the file, like it's name, creation date, modification date, etc., along with the physical location(s) on the disk. When you delete a file, you really only delete the index entry, without which, the file becomes inaccessible, and the space on the disk will be written over at some future time, when a new file is stored there. StuRat (talk) 17:07, 24 February 2013 (UTC)[reply]
At an abstract level, a file is generally a sequence of bits (0 or 1 values), usually organized in bytes (8 bits together). The bytes may be physically in a row or spread out in pieces called sectors, with information somewhere about which sectors belong to a file. File storage media usually contain something which can be in two states, interpreted as a 0 or 1 value of a bit. For physical details of the two states in some common file storage media, see Magnetic storage (hard disks), Optical disc (CD's and DVD's), Flash memory (USB flash drives). PrimeHunter (talk) 17:26, 24 February 2013 (UTC)[reply]


One way to imagine how it works, the disc is a a ring-binder with rewritable plastic sheets. Each sheet can only hold the contents of one file; larger files need multiple sheets. The sheets can't be reordered. You can open the binder directly at any numbered sheet. The sheets correspond to disk sectors. Ideally, when writing out a file, you'd choose a contiguous block of sheets; however if you don't know what size of the file is, then you either have to pick too large a empty block of sheets (leaving a small number of empties at the end), or pick a too-small block, then pick another block when that one is filled. Either way, this leads to disk fragmentation; the first is free-space, the second is file. Each folder (directory) is just a special file, which lists all the file names, and other meta-information. There are also other special files indicating all the sheets that belong to each file, and the unused sheets. When you delete a file, the sheet is marked as being unused, however it is not wiped clean; this is how undelete programs work. CS Miller (talk) 17:37, 24 February 2013 (UTC)[reply]
The answer to this question also depends on the definition of "file." For example, the C standard library has a FILE API, and that specification defines a well-documented contractual obligation between the hardware and the program. The Windows CreateFile API specifies a different well-documented contractual obligation between the hardware and the program. Device programmers who work with low-level details of file-systems have very well-documented specifications that explain what a "file" is, and so on. Ordinary users, who interact with files through user-interfaces at the application layer are actually working with a less-well-specified, less-well-documented definition of "File." For example, if you create a document in a modern word-processing suite, you are actually creating several files. Many users treat the document - which is an application-layer abstraction - as if it is interchangeable with the file, which is a reasonably good approximation for many cases. But if we want to discuss how that file translates down to the hardware representation, we need to proceed very carefully: we need to describe all the application behaviors, fully; and we need to define the file-system, and the way that the operating system and disk drivers will commit the file-system to physical storage, and so forth. Nimur (talk) 19:37, 24 February 2013 (UTC)[reply]
I think the above explanations, while correct, may be a bit too technical.
Physically, your "file" is a series of magnetic charges on a disc. A charge one way counts as a 1, while the other counts as a zero: this is binary counting. Computers can sense the magnetic changes on the disc and, through some complicated processes, translate that from the 1s and 0s of your file into something you can see & understand on your screen.
So, your file physically exists as a magnetic field on the disc inside your hard drive. — The Hand That Feeds You:Bite 19:02, 27 February 2013 (UTC)[reply]

Using email client with free email accounts[edit]

If you use an email client you won't be seeing any ads. So, free email account will be free of income for the provider. But, why do some companies still allow you to connect this way? Where is the business? OsmanRF34 (talk) 21:52, 24 February 2013 (UTC)[reply]

Ignoring that they can read all your email, you still depend on them, and they can force any number of things (including ads) on you at any time in the future (but might be happy with just having you alter your prefs on their website for now). ¦ Reisio (talk) 22:23, 24 February 2013 (UTC)[reply]
For many providers, especially big ones like Google, Yahoo or Microsoft, free email accounts are just one part of a much broader strategy. They are willing to accept that they won't make money on all use cases. It means that they can offer a better user experience and makes you more likely to use their other services. Some of those other services or features make money, either through ads or through fees, or at least they will do so in the future. KarlLohmann (talk) 05:35, 26 February 2013 (UTC)[reply]

Some of them add adverts into the emails itself, on both incoming and outgoing messages. 92.233.64.26 (talk) 18:03, 25 February 2013 (UTC)[reply]

Sony Li ion battery terminal descriptions[edit]

What are the 'C' and 'T' terminals in the four-terminal Sony Type K Lithium Ion camera battery? 67.163.109.173 (talk) 23:32, 24 February 2013 (UTC)[reply]

This datasheet identifies the four terminals of a "standard" Li-ion battery: GND, B+, B-, and T. T is a termistor connector, allowing the charge circuit to monitor the battery temperature. I don't know about C; it may be Sony's name for B- Finlay McWalterTalk 00:04, 25 February 2013 (UTC)[reply]
On thinking about it more, are you sure the terminals aren't labelled + - T and G (G for ground, rather than C) ? -- Finlay McWalterTalk 12:01, 25 February 2013 (UTC)[reply]
Here's a picture from the Internet that looks just like mine. It's definitely a 'C'. 67.163.109.173 (talk) 12:16, 25 February 2013 (UTC)[reply]
Sometimes, the term "common" is used to refer to "ground" - especially if "ground" is actually the chassis, and not actually the ground. C may stand for "case", or "chassis," or "common." Nimur (talk) 16:41, 25 February 2013 (UTC)[reply]