Wikipedia:Reference desk/Archives/Computing/2012 August 30

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Computing desk
< August 29 << Jul | August | Sep >> August 31 >
Welcome to the Wikipedia Computing Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

August 30[edit]

Smart TV software updates[edit]

Hi, on a Samsung "Smart TV", one of the software update options is called "By Channel", described as downloading the update "over broadcast signal" (other options being over the Internet and from USB). What kind of "broadcast signal" would that be referring to? I am in the UK if that matters. (talk) 01:31, 30 August 2012 (UTC)

Freeview (UK) carries TV software updates on one of its channels. I nearly fell off my sofa when my Sony TV first announced that it had received a software update and was intent on installing it. See, for instance, this schedule. --Tagishsimon (talk) 01:37, 30 August 2012 (UTC)
(OP) Really, I didn't know that... Thanks for the quick reply. (talk) 01:57, 30 August 2012 (UTC)


I have a website which should be advert free. Occasionally a pop up screen appears. How do I stop it so it doesnt appear for other people? Kittybrewster 11:42, 30 August 2012 (UTC)

I had a poke around your website, but didn't get any popups or popunders. Then again, I have fairly robust popup blockers. It might help us to know where you are having the problem, and what steps can reproduce it. It's always possible that it's not something on your website at all - if it occurs when navigating from an external site, that site could be using an 'exit popup' - that is, a window that only appears when you navigate away from it. - Cucumber Mike (talk) 11:52, 30 August 2012 (UTC)
Or it could be malware on your own machine causing the popups. --Mr.98 (talk) 12:25, 30 August 2012 (UTC)
Carefully consider any third-party code you have added to your page (for statistics, counters, and so on). For example, this 2005 thread on the Straight Dope Message Board suggests a image causes a pop-up the first time a visitor loads it, but sets a cookie to prevent the pop-up from re-appearing. If any of your visitors are using browsers from 2005, maybe they're experiencing something similar. --Bavi H (talk) 02:55, 31 August 2012 (UTC)

iOS's Safari cannot upload files[edit]

Why does the Safari web browser built into iOS cannot upload files? (talk) 13:00, 30 August 2012 (UTC)

Is a hard disk drive a type of RAM?[edit]

Hard disk drive states in second paragraph that "Hard drives are classified as non-volatile, random access, ....." but Random-access memory says "In contrast, other data storage media such as hard disks, CDs, DVDs and magnetic tape read and write data only in a predetermined order....."--Gauravjuvekar (talk) 16:07, 30 August 2012 (UTC)

I think hard disks and CDs/DVDs are always classified as random access, but they aren't classified as memory. "Memory" only covers RAM and ROM. Of course, ROM is random-access and it is memory, but it isn't RAM. And data CDs are called CD-ROMs but they aren't ROM and aren't memory. Basically the definitions make no sense. I'll try to fix the lede of the RAM article at some point if no one else does. -- BenRG (talk) 16:49, 30 August 2012 (UTC)
This is another case of "standard terminology" not being so standard. "Random access" is being used in two different ways: in the hard disk drive article, to mean all data is addressable; and in the random-access memory article, to mean all data access takes equal time.
Nearly all file APIs provide some method for byte- or word- addressability - especially if they present the files as though they are mapped to memory. However, internal to the disk controller driver, or the file system implementation, nearly all hard disks addressed by sector; and many file-systems are paged into RAM. The details vary between each product, driver, file system, and operating system. So, every byte is accessible ("random access", according to the first meaning). But, spatial locality dictates that some bytes can be accessed faster than others (not "random access", according to the second meaning). Nimur (talk) 17:02, 30 August 2012 (UTC)
Modern DRAM is organized into rows and there is a delay in switching from one row to another. It's really a difference of degree, not kind. For RAM the random access penalty is a few nanoseconds, for a hard disk it's a few milliseconds, for CDs it's a few tenths of a second, and for tape it's a few minutes. It's somewhat arbitrary where you draw the line, but I think CDs are always considered random access media and tapes usually aren't. -- BenRG (talk) 19:47, 30 August 2012 (UTC)
Surely the reason for this is that, with tape you have to read through all the data between where you are and where you want to be, so it's purely serial. With disks, you can skip across unwanted data, so it's not serial and is traditionally called random. --Phil Holmes (talk) 08:58, 31 August 2012 (UTC)
I like Phil's definition: if it's serial it's not random-access. that's how I always understood the phrase. But I suspect there's no good consensus about what the term exactly means. I'd be glad if someone proved me wrong on that point. Shadowjams (talk) 19:14, 31 August 2012 (UTC)
Is that even correct though? Our [1] while somewhat confusing seems to suggest it is not with most modern tapes. You can normally just quickly wind to the correct position even if quickly here is still quite a while. (I.E. You don't have to read all the data in between.) It's still true you have to wind the tape, unlike with optical media and hard disks or even floppy disks where you just have to reposition the head (with the discs constantly moving) but I don't know whether you can really say this makes it purely serial. If we imagine a 'tape' system where instead of in a casette the tape is stretched along a very long line and head head has to move along the tape, with not moving at all, is this really that different from the disc systems (yes the tape isn't moving unlike with discs, but I don't see why that makes it more 'serial'.) P.S. I'm not sure whether you find the exact right position of a tape straight away but I don't think you can with most optical media either. P.P.S. I'm not saying tapes should be considered random access, rather saying BenRG seems to be correct. It's an arbitary line. While the tape article is somewhat unclear as I mentioned, my impression is that's basically what it's saying. With a tape, the difference between sequential and random access is so great that they normally aren't considered random access. Nil Einne (talk)

Google Doesn't Work[edit]

No matter what I enter or where I enter it, either in the Google homepage or in the bar at the top of the screen, all I get is a blank page with "done" at the bottom. I've scanned thouroughly for viruses and waited a long time but still nothing. What can be done? If I switch to Bing at the top of the screen it works. — Preceding unsigned comment added by (talk) 17:02, 30 August 2012 (UTC)

There are a number things which may be causing this. You didn't say what browser or OS you are using, but from the information you have given I would guess a version of Internet Explorer. Do you have any other browsers on your system, such as Firefox or Opera with which to test? This would help determine whether the problem is being caused by the browser or something else, so that we can concentrate our troubleshooting efforts more effectively. If not, with the blank "done" page loaded in Internet Explorer, go to "View" -> "Source" to display the html code of the page. If you see a mostly empty page with "<META HTTP-EQUIV="Refresh" CONTENT=" this is an issue with Internet Explorers meta refresh settings and you will need to change them by going to "Tools" -> "Internet options" -> "Security" -> "Custom level", scroll down to the "Allow META REFRESH" setting at change it to "Enable". Clearing the browser cache/history at this point would probably be a good idea too. If this didn't solve the issue, then we should check that your internet connection is routing traffic properly to googles servers. Do this by opening the command prompt and type
You will then see the route your connection takes to the google server, and the result should end at a hop named "" If you don't see this, then there is something wrong with the connection, perhaps a routing issue on your ISP, or your host file has been altered (possibly by a virus or malware). The host file article explains where to locate the file on your system. Open it with notepad and if there are any entries for google, remove them (do not remove or add anything else though). If none of this solved the issue, please post back with more information about which browser, version, and operating system you are using AvrillirvA (talk) 20:07, 30 August 2012 (UTC)

Dear AvrillirvA, Thank you so much for your detailed reply. My Google hadn't been working for a week. I have two PCs connected to the same line, so I knew it wasn't the internet connection routing traffic improperly because the other one worked. I just now turned on my PC and went straight to this page, printed it, and then went to the Google homepage. I keyed in "Mitt Romney" and before I could even hit enter the page was filled. I hadn't changed anything since it didn't work. I did check out the "<META HTTP-EQUIV="Refresh" CONTENT=", page was full. I also checked META REFRESH and it was already on enable. I can't explain why this problem healed itself but now, thanks to you, I'll know what to do if this problem ever comes back. Thank you again. — Preceding unsigned comment added by (talk) 16:50, 31 August 2012 (UTC)