Wikipedia:Reference desk/Archives/Computing/2010 February 24

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February 24[edit]

Color of computer case[edit]

When did the standard color for a computer case change from beige to black? Why? F (talk) 00:49, 24 February 2010 (UTC)

Alas, our Beige box article has not much on when and why it changed. My feeling on "when" is not earlier than 1999, and not later than 2003, just judging on computers I have had. As for why, it is just marketing, I am sure. --Mr.98 (talk) 01:47, 24 February 2010 (UTC)
Dell has predominantly used black computer cases for at least 8 years. Why? I don't know. From memory, Dell was the first computers we started getting at the hospital/university I worked at that weren't beige. Gateway was still beige for a while. It then switched to a choice of white or black. From my personal experience, I attribute the majority of the switch to Dell. -- kainaw 03:50, 24 February 2010 (UTC)
I believe one reason was when PCs were touted as being an all purpose media device that could interface with your TV and audio equipment (perhaps around the time that Windows Media Center was introduced in late 2002), people were reluctant to put a beige box in their living room. A black box was more in keeping with a piece of entertainment equipment.
It is worth noting, audio and video equipment seems to alternate between black and silver finishes every few years. I've always though that it was to do with marketing, promoting the idea that people could boast they have the latest and greatest equipment ... "you can tell its new 'cause it has this year's black finish rather than the old model's silver finish", then in a few years "you can tell its new 'cause it has this year's silver finish rather than the old model's black finish". Astronaut (talk) 04:42, 24 February 2010 (UTC)

Here in the Uk the switch from Beige to black seemed to happen around the same time that PCs changed from being simply boxes that hold components to being boxes that had a bit of design/style applied to them (not necessarily good style but nonetheless). This seemed to coincide with the (media) success of the original Apple iMacs which were in those bright colours and made PCs look 'dated'. I suspect that this was also in part linked to the point where PCs became 100% mainstream and that every home in the land had one - rather than being more the preserve of businesses and enthusiasts. 194.221.133.226 (talk) 09:50, 24 February 2010 (UTC)

Definately around 2000 (same period as the PS1(cream-grey) >> PS2(slate) switch) - reason - It makes them go faster [1] ! 87.102.67.84 (talk) 11:34, 24 February 2010 (UTC)

LOL! Did they test beige cases that were painted black? Was there a placebo effect? I think a more scientific approach is warranted. Er. Um. Nevermind. --144.191.148.3 (talk) 14:22, 24 February 2010 (UTC)

Also blue LED+beige box = fashion disaster...87.102.67.84 (talk) 11:41, 24 February 2010 (UTC)

I agree that 2000 is probably the best guess. The first black box I recall seeing was for an Aptiva, which was discontinued in 2001 (though note that the photo in the article is of a beige box). Normally, I wouldn't be able to recall a detail like this, but the commercial was also distinctive because it ended with the computer saying "Hello, I'm Aptiva" in such a way that viewers were supposed to think that the computer was literally greeting them rather than simply playing a sound file of a pseudo- computer generated voice. And... it was black and therefore modern and capable of such things as sentience. Matt Deres (talk) 17:32, 24 February 2010 (UTC)
You can't beat the Apple aluminium MacBook Pro case!--88.109.166.197 (talk) 08:46, 25 February 2010 (UTC)

PC is running on battery but it's still plugged in[edit]

Well, what the title says. But it's plugged in on both ends, yet the battery icon is present. And the battery is running out faaaaaaast. Can anyone tell me why is that so? And what do I do about it? 24.189.90.68 (talk) 05:55, 24 February 2010 (UTC)

When this happens to me, it is always because the cord from the wall has fallen out of the power brick. What model laptop is this? Does it have some sort of LED next to the power plug indicating that it is plugged in? Is the 'battery icon' a light near the computer keyboard, or do you mean it is on the screen? Comet Tuttle (talk) 06:01, 24 February 2010 (UTC)

It's a Dell Inspiron 6000, yes there's a light in the plug indicating that it's plugged in, and the battery icon is on the screen. I've got less than half an hour left before it shuts down on me (don't worry, I'm typing this on another computer, though). 24.189.90.68 (talk) 06:12, 24 February 2010 (UTC)

I just figured out the problem is with the adapter, because I switched it with another, and it charges fine. 24.189.90.68 (talk) 06:16, 24 February 2010 (UTC)

Do they sell Dell adapters in stores or must you order them? 24.189.90.68 (talk) 06:45, 24 February 2010 (UTC)

I think dell will sell their own (via their website - try customer support > spares), or you can get an equivalent one usually very easily - you would need a match for the plug, voltage and current/wattage. (I just had a look on Dell's website and it will be a lot cheaper to buy elsewhere.87.102.67.84 (talk) 11:23, 24 February 2010 (UTC)

Database integration[edit]

what is the effectiveness of databse intergration in hospitals? —Preceding unsigned comment added by 41.203.179.235 (talk) 09:41, 24 February 2010 (UTC)

The effectiveness depends on the implementation - I'm guessing you meant "why use a database in a hospital"? -- the answer is the same for the use of databases in other applications - for discussions of why see:
[2] , [3] , [4] 87.102.67.84 (talk) 12:49, 24 February 2010 (UTC)
It is highly possible that this is asking about integrating clinic data with hospital data. The clinic data is stored in an outpatient clinic system. The hospital data is stored in a hospital system. When you see your outpatient doctor, he will have access to your hospital data. When you go to the hospital, the doctor there will have access to your outpatient data. The benefit is more health information used to make better decisions.

Issue with debootstrap and preseeding wrt/ non-us keyboard layouts?[edit]

Hi,

I installed a minimal Linux system using debootstrap and chrooted into it. In the chroot, I run:

debconf-set-selections <preseed.txt && apt-get dselect-upgrade -d -y && apt-get dselect-upgrade -y

The problem I'm facing is that even though preseed.txt contains all the necessary info to preseed console-setup and console-data, the keyboard layout remains the standard US one, even after logging out and back in again. This happens in Debian Lenny as well as in the Ubuntu releases I had at hand for testing.

dpkg-reconfigure -fnoninteractive -pcritical console-setup && dpkg-reconfigure -fnoninteractive -pcritical console-data doesn't change the situation either, so the system seems to firmly believe it is doing the right thing with keeping the US layout. Only when I run dpkg-reconfigure manually on those two packages I am prompted with the options to change the keyboard layout (with the default options being the US settings, again), and the changes are finally taking place.

Surely there must be a way to preseed keyboard settings for an unattended install? What is the proper, "Debian" way of doing this? -- 78.43.60.58 (talk) 12:16, 24 February 2010 (UTC)

Internet 1995[edit]

How many internet user in 1995 —Preceding unsigned comment added by 203.82.92.31 (talk) 12:30, 24 February 2010 (UTC)

[5] or search google for "internet use 1995" , "historical internet use" "internet use statistics" etc.87.102.67.84 (talk) 12:40, 24 February 2010 (UTC)

ISO image...[edit]

A friend gave me an ISO image which is apparently of a software CD. However, when I burn the image to a disc, it only has the individual folders and files, which obviously are of little use without the software package itself. Any hints or tips? Thanks! ╟─TreasuryTagsundries─╢ 14:14, 24 February 2010 (UTC)

How are you burning the disc? You need to use a specific tool for ISOs. --LarryMac | Talk 14:22, 24 February 2010 (UTC)
I used the Roxio "burn image to disc" tool... ╟─TreasuryTagquaestor─╢ 14:58, 24 February 2010 (UTC)
It is possible that your friend didn't understand what he was doing and just did a drag/drop from his C:Program Files/ folder - thinking that would copy the whole program. You can show him how to rip a CD and then burn it so he can do it correctly in the future.

Curious google result[edit]

I was checking to see if anyone had a blog about the city in which I live - so I did this search http://www.google.co.uk/search?q=kingston+upon+hull+blog&btnG=Search&hl=en&rlz=1C1CHMA_en-GBGB367GB367&sa=2 (the answer seems to be no - non of any note..) - but the first result returned is one http://schizomuslim.blogspot.com/ ?? Looking at that page I can't find any reference to the location - can someone explain why this is the very first result google turns up>87.102.67.84 (talk) 18:34, 24 February 2010 (UTC)

Not clicking the link but just reading the name of the blog I think it looks like one of those hate-monger sites and probably it is first on google because some people do some trickery, like guiding other people to this site. 95.115.158.3 (talk) 19:07, 24 February 2010 (UTC)
No. The blog is very moderate and peaceful, it's also via google's own blogger software which I would guess limits any misrepresentation by meta-data spamming.87.102.67.84 (talk) 19:19, 24 February 2010 (UTC)
Just to clarify for those who don't want to click the blog link - the blogger has only ~4 follows and barely a page of posts - and nothing about kingston about hull in it - so wtf is it doing at the top of my search results??87.102.67.84 (talk) 19:52, 24 February 2010 (UTC)
Viewing the page's source, there aren't any relevant meta tags. Comet Tuttle (talk) 19:56, 24 February 2010 (UTC)
It looks like the blogger (or someone else, perhaps without his knowledge) has registered this blog as a "business" at that address, using the Google Local Business Center system. Note, incidentally, that if you zoom in on that specific address, it resolves exactly to the offices of Humberside Police. -- Finlay McWalterTalk 19:59, 24 February 2010 (UTC)
Thanks - didn't notice that. I though the map was appearing because I typed a city name - didn't notice the marker or give it a second thought. very very strange (and quite funny looking at it obtusely enough). So some joking around has got this site onto the search results by the sound of things.87.102.67.84 (talk) 20:28, 24 February 2010 (UTC)

java.lang.IllegalStateException: getOutputStream() has already been called for this response[edit]

I'm building a web application that runs on tomcat. At a point, I need to generate a zip-file (containing many individual files) and send it to the user's browser for download. It works (file can be downloaded and unziped) but whatever I try I get the above error message. I do a outs = response.getOutputStream(); and use this stream to create a final ZipOutputStream zout = new ZipOutputStream(outs); . Obviously the framework has some built-in jealousy on other people calling getOutputStream(). How can I avoid this?

And yes, I did a google search. And yes, I found many answers. And yes, I have tried them. And no, none of it worked. And again no, I can't use the JspWriter out that is availabe in the response-Object because I have to write bytes, not chars.

95.115.158.3 (talk) 18:53, 24 February 2010 (UTC)

Is this in the context of a servlet? Or is there something else that might be trying to create (say) a Writer that would call getOutputStream() ahead of you? Moreover, what do you mean that "it works" but "whatever I try I get the above error message"? Surely if an exception is being thrown in your servlet before you actually compress and send the files, then they aren't being sent and you can't download and unzip the result. Are you saying that message just somehow appears on the console without a backtrace or anything? Or that it somehow gets transmitted to the client (along with the file, perhaps)? Is it (to your knowledge) associated with one of the two lines of code you quoted? --Tardis (talk) 23:55, 24 February 2010 (UTC)
Somewhat after posting the question I realised that I probably have a double problem. On a jsp-generated page the user selects options and on pressing ok a post-request is sent to that page but forwarded to a servlet that does part of the processing. The resulting zip-file is transmitted to the user's browser correctly, can be unziped and contains no garbage. The error message looks quite like any java error written by printStackTrace() and appears either in the tomcat logfile or (if called from eclipse) on the console. As far as I can debug the last line of source code it passes is "_jspxFactory.releasePageContext(_jspx_page_context);" within the generated *_jsp.java before it drops out of sight in the framework. Lately I tried response.reset() at the beginning and end of the doPost() of the servlet: now the error message is doubled and origines from those response.reset() lines in the servlet, somehow without breaking the flow. It gets me crazy and I really wonder how other people are doing this. 95.115.141.196 (talk) 06:11, 25 February 2010 (UTC)
It's gone! There where new line chars in the first jsp between the <%@page ..> tags. But this is no real solution because whenever the jsp is automatically formated the error will be back again. 95.115.141.196 (talk) 06:56, 25 February 2010 (UTC)
My guess is that it is because you are writing to the output stream (the new line) before using it for the zip output. Try doing a reset on the output stream
outs.reset();
before passing it to the ZipOutputStream. -- Q Chris (talk) 08:19, 25 February 2010 (UTC)
As far as I can see neither the class OutputStream nor ServletOutputStream has such a method. 95.115.141.196 (talk) 08:55, 25 February 2010 (UTC)
You could try reset or resetBuffer on the HttpServletResponse —Preceding unsigned comment added by 213.38.213.226 (talk) 11:11, 25 February 2010 (UTC)
Done that, see above. No use. 95.115.141.196 (talk) 11:20, 25 February 2010 (UTC)
It sounds as though formatting without newlines is the only way to go in .jsps; see [6]. You could use s servlet instead of a .jsp, I think this is more usual when dealing with non character based data. -- 213.38.213.226 (talk) 13:49, 25 February 2010 (UTC)
Thank you for the link. Actually, as stated above, I am using a servlet but also a jsp which initiates and forwards to the servlet. I belive this is the main source of trouble. 95.115.141.196 (talk) 13:58, 25 February 2010 (UTC)
Can you use response.sendRedirect() from the JSP page? I know that this has limitations, i.e. not working with POST, but if you can use it then the sevlet will have a completely new request and be unaffected by the JSP. -- Q Chris (talk) 20:40, 25 February 2010 (UTC)

Three copy/paste problems[edit]

Problem no. 1: Narrow emails

I used a different email address than usual at a library to copy and paste the text of several newspaper articles, intending to print them out in a long email later. This morning, I discovered that the email I sent myself was narrow, meaning that I had to waste time using the delete key at the end of each line. I normally use Hotmail but only after copying and pasting from a notepad. The quirks of Firefox explain why that's my normal procedure, but I have numerous email addresses and need to use them all. Yahoo and Gmail have the same problem with narrow emails, both those received and those sent. Lycos has announced changes that I hope won't affect its ideal behavior where this is concerned. Full-width emails in the printable version will use less paper, and these can only be produced from full-width emails that I have sent myself.

Problem no. 2: Looks blue but isn't?

It looks blue, so I copy and paste. I get either nothing or something I already copied and pasted. Why does it look blue if I can't use it?

Problem no. 3: How did it turn blue? I didn't do anything

I deleted an email and then when the next one came up it was completely blue as if I was copying and pasting not just the text, but all the headings, lists, ads, etc. The same strange phenomenon happened in another situation where I merely clicked the mouse without doing anything to make the text turn blue.Vchimpanzee · talk · contributions · 20:01, 24 February 2010 (UTC)

Problem #1 is a "word wrap" problem. Somewhere along the line, most likely when sending the e-mail, your e-mail client decided to insert newline characters in your e-mail in order to (it thought) make it more readable. You are having to use the delete key to get rid of the newline characters so that the text will flow like a normal paragraph. I just did a little testing to send e-mail back and forth to a Yahoo Mail account, and found the following: (a) no newlines were added when sending a "Rich Text" e-mail (that's what Yahoo Mail calls it) from Yahoo Mail to Microsoft Outlook 2007; (b) no newlines were added when sending a "Plain Text" e-mail from Yahoo Mail to Outlook; (c) no newlines were added when I used Outlook to reply to the "Rich Text" e-mail; (d) newlines were added when I used Outlook to reply to the "Plain Text" e-mail. You might want to test Yahoo Mail a little more, and make sure you're set to "Rich Text" if possible; it looked to me like Yahoo's e-mail client is not the culprit. Comet Tuttle (talk) 20:23, 24 February 2010 (UTC)
On the subject of wasting time, you can get a better text editor than Notepad and then you'll have less trouble when something like that happens. For instance, in Emacs, to re-wrap a paragraph of text is just M-q. (Meta is often the same thing as Alt.) You can choose the width to which to wrap it with a few more keys; setting a very large value for that will cause all the newlines to be deleted at a stroke. --Tardis (talk) 20:56, 24 February 2010 (UTC)
Based on VChimpanzee's previous posts, I would say he or she is as likely to use emacs as to win the gold in snowboarding on Saturday. Comet Tuttle (talk) 21:36, 24 February 2010 (UTC)
Emacs is just an example of how much easier it can be. Perhaps I should have linked list of text editors; I hear (from this desk) that people like Metapad, for instance, which is supposed to be a Notepad replacement and might be more appropriate in this case than Emacs. --Tardis (talk) 23:48, 24 February 2010 (UTC)
I use plain text for most of my emails to myself. As I said, I'm trying to save space. Plus there are numerous problems with not using plain text to copy newspaper articles. Such as photos I don't want and even video, which causes serious problems. I don't even use an email client. Yesterday I used AOL because I can use a pop-up screen for what I type. Not that I would have to. But at the library where I'm on Firefox, it's a requirement. Excite is what I use there. Not Notepad software, but Excite in this situation is no better than a notepad. But when I copy and paste to Hotmail, I get the result I want.Vchimpanzee · talk · contributions · 21:16, 24 February 2010 (UTC)
(a) It sounds like you've found a solution, so you don't need any further info on #1; is that correct? (b) You might want to re-evaluate whether you really need to 'save space' — GMail, for example, gives every user over 7.4GB of storage, "and counting"; and you're never going to fill that up with photo thumbnails inadvertently copied from news websites. I agree that the extra junk is annoying when attempting to copy and paste many web sites' text. Comet Tuttle (talk) 21:36, 24 February 2010 (UTC)
I'm not referring to a solution. I'm wondering why these things happen. As for "saving space", it costs money to print pages. I don't have a printer at home because it took me long enough to have the courage to just use a computer on my own. Not to mention the expense and problems a printer would add. Actually, I just realized a printer would be cheaper than all these printouts. But having a printer would produce its own new problems.Vchimpanzee · talk · contributions · 22:00, 24 February 2010 (UTC)
No.1 Bit fiddly - I see why you need to use plain text - to get rid of 'stuff' - it sounds like (from the experiments above), that if you then copy the plain text into wordpad (or whatever) and save it as richtext (.rtf) - it can be sent without adding newlines, definately fussy to do - maybe theirs an option in the e-mail client to fix this - though I definately can't find one in hotmail - maybe another mail client will do better.
No.2 You were using an unfamiliar computer - did you use a method that definately copies the text - or a keyboard shortcut - sometimes different pieces of software use different keyboard shortcut for copy. Maybe that's why it didn't work.
No.3 Just a bug by the sounds of things - can't think of a proper reason why this would happen. (all these problems are on the library computer ? not your home one?)87.102.67.84 (talk) 22:29, 24 February 2010 (UTC)
Normally, I use plain text with Excite email and copy to rich text Hotmail. This is done at a library and works fine.
At home inbox.com does the same thing, but after problems with rich text I began using Yahoo plain text as a notepad. The original question explains why I can't just send Yahoo plain text. Actually, inbox.com does have a plain text option I keep forgetting about, but I don't know whether I'd end up with the narrow text. Why not use hotmail at home? Well, I haven't yet. And hotmail is a pain these days. I just happen to have my inbox username and password saved at home.
No. 2 would more than likely be at a library, but if the nearest one is closed and I wouldn't have been driving anywhere, I do it at home. With Internet access 3 times dial-up speed, looking at newspapers is fun. No. 3 is at home.
I doubt I could use emacs at a library, and I certainly won't at home.Vchimpanzee · talk · contributions · 17:57, 25 February 2010 (UTC)
On #2, this happens to me sometimes, often when copying and pasting graphics, and I find it incredibly annoying, too. Occasionally it's because I hit ctrl-C to copy when my window is not actually the selected window — some other app has made Windows de-select my window, which you can only tell because the window's title bar dims and changes its color gradient a little; so when I hit ctrl-C, I'm sending that keypress to some other app. But sometimes it's for reasons I don't know. Sometimes ctrl-C won't do anything even on repeated presses when the window is clearly selected, which I attribute to a bug in the program I am using. My workaround has been to use the "Copy" and "Paste" items in the "Edit" menu when this occurs. I know this isn't a very rigorous paragraph and if I cared deeply about it I would have narrowed down the circumstances of the bug and reported it to someone. Comet Tuttle (talk) 17:59, 25 February 2010 (UTC)
This phenomenon usually causes the color to change to gray. I find I can use Ctrl-C after time has passed, but it's frustrating because I have to back and fix what I pasted, and sometimes the blue area isn't even the same area it was.Vchimpanzee · talk · contributions · 21:54, 25 February 2010 (UTC)

can one iPhone concurrently run apps from different App store account users?[edit]

Say I log in on my account on somebody's iPhone, download an App after paying for it, then log out again. Can they then proceed to log in to their own App Store account, which will not include the purchase, while coninuing to enjoy the Use of the app I bought them (unless or until they delete it of course). THank you. 84.153.235.131 (talk) 22:26, 24 February 2010 (UTC)

Like all great plans this seems to be flawed - bought apps are tied to a user account (using Fairplay DRM I think) - so no, unless...you're married 87.102.67.84 (talk) 23:36, 24 February 2010 (UTC)