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Wikipedia:Reference desk/Archives/Computing/2009 October 18

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October 18

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Making a binary file from hex data in the command line...

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If I have a binary file that I want to print it out as hex data in a terminal, you can just use the "od -h" command. Is there any way you can do the reverse, that is, have a bunch of hex data and assemble it into a binary file? 83.250.228.169 (talk) 00:44, 18 October 2009 (UTC)[reply]

xxd can do hexdumps and reverse. --194.197.235.240 (talk) 00:49, 18 October 2009 (UTC)[reply]
Just echo -e '\x##\x##' >file should work, if it's not a problem to put the data on the command line in that format. If you'd rather, perl -e 'while(read STDIN,$_,2) {print chr hex;}' will read a solid block of hex from stdin (no spaces or newlines) and write the corresponding data on stdout. Variations could easily be made to handle different input formats. --Tardis (talk) 01:08, 18 October 2009 (UTC)[reply]
Similarly in Python, strings have .encode and .decode methods for translating them into specific encodings, one of which is hex. So "foo".encode("hex") returns "666f6f", and "666f6f".decode("hex") returns "foo". --FOo (talk) 04:28, 18 October 2009 (UTC)[reply]

ref tag in html?

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Is there such a thing similar to the ref tag in wikipedia? I know that you can use an anchor to duplicate it, but when you add an anchor link in between two others, you have to change the ones after it and if you have like 100 references, you have to do a ton of work. So does anyone know if there is a way similar to the ref tag in wikipedia in html or something else (cascading style sheets etc). —Preceding unsigned comment added by Renassault (talkcontribs) 04:05, 18 October 2009 (UTC)[reply]

We have this - Template:Anchor. Nimur (talk) 04:40, 18 October 2009 (UTC)[reply]
sorry, I don't understand what that says (I think it talks about how to do it on a template). Is it saying you can't do it with <a name="x">? (also, sorry, I dont know how to sign my name). —Preceding unsigned comment added by Renassault (talkcontribs) 04:53, 18 October 2009 (UTC)[reply]

Here you go. I just made one up for you:

<html>
	<head>
		<script type='text/javascript'>
			function setRefs()
			{
				for (i=0; i < document.getElementsByTagName("span").length; i++)
				{
					document.getElementsByTagName("span")[i].innerHTML = '<sup><a href="#references">' + (i+1) + '</a></sup>';
				}
			}
		</script>
	</head>
	<body onload="setRefs()">
		Lorem ipsum dolor sit amet,<span></span> consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et 
		dolore magna aliqua.<span></span> Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex
		ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat
		nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim
		id est laborum
	</body>
</html>

Once the page is loaded, the "setRefs" JavaScript function runs. All of the generated links point to a section called 'references'. Feel free to rename either the function or the section name. You could also do it using the document.getElementsByName method, if you wanted to. The body above is just boilerplate text. You add a span tag wherever you want a citation. I don't know how Wikipedia does it, but I like to keep my code as simple as possible.--Drknkn (talk) 06:43, 18 October 2009 (UTC)[reply]

Thanks a lot man, you're the best--renassault

Google search has changed

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I just noticed, when I go to use Google to search for something, the "search" and "I feel lucky" buttons have disappeared. Is it just me, or has Google made their front page like this for everyone? Astronaut (talk) 05:51, 18 October 2009 (UTC)[reply]

They're there, no doubt about it. Wanna screenshot? --Ouro (blah blah) 06:32, 18 October 2009 (UTC)[reply]
No, I believe you. Does Google now have a fade-in effect? Astronaut (talk) 06:40, 18 October 2009 (UTC)[reply]
It's a feature they've been testing out. Indeterminate (talk) 08:31, 18 October 2009 (UTC)[reply]
Looking around, I came across this forum page and I agree with many others - the fade effect and missing buttons is something that Google should ditch (or at least make it a selectable option in their preferences page). Astronaut (talk) 10:30, 18 October 2009 (UTC)[reply]

Either Google's experiment has finished, or my deleting all cookies has fixed it. Google's now back to how it was, with both buttons and no annoying fade effect. Astronaut (talk) 04:24, 19 October 2009 (UTC)[reply]

hdmi monitor

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Hello there. I have an hp 15.4" laptop to which i would like to connect an LCD monitor. It's gonna be a 22-23 inches one with an hdmi input and my lap too has an hdmi output, so I thought would there be no problem trying to hook it up throu hdmi to a monitor that has that input? I just supposed that an hdmi output on laps is usually used for projecting the signal to a big HD tv or something similar , do you think itd be okay if i do that? —Preceding unsigned comment added by 77.35.46.140 (talk) 14:39, 18 October 2009 (UTC)[reply]

For your purposes, there really isn't a difference between a modern LCD TV and a modern LCD monitor, so I don't believe you'll have any problems. -- Finlay McWalterTalk 14:51, 18 October 2009 (UTC)[reply]
The only consideration is whether the graphics card on your laptop can handle your monitor's native resolution. Any other resolution could look fuzzy if either your monitor or laptop doesn't come with auto-correcting software. Sandman30s (talk) 19:31, 18 October 2009 (UTC)[reply]
Sandman30s is correct. (I would go further and forget about auto-correcting software; you must get a graphics card that can support the native resolution of the monitor.) See our article native resolution for details. Tempshill (talk) 20:52, 18 October 2009 (UTC)[reply]
Based on my experience, you should not have big problems - if your laptop manufacturer fitted a HDMI port, I would be very surprised if the laptop's graphics card didn't support it at a range of resolutions to suit your new monitor. All the same, I wouldn't invest many $ in a HDMI cable until you are sure it works well.
That said, my TV has a feature which crops the image by some pixels all round, so I don't see odd things flickering at the screen edge such as Teletext, closed captioning etc. I can switch this feature off on my TV and get all 1920x1080 pixels displayed, but I'm unsure about other TVs (eg. I don't think my sister's Philips TV can switch off this feature). A few pixels is not important with TV, but when I tested it at my sister's house I could only see the top half of Vista's start button and with maximised program windows the "Window close" button had almost disappeared. Astronaut (talk) 01:12, 19 October 2009 (UTC)[reply]
Not that you shouldn't really have to invest many $ in a HDMI cable period. Most cables particularly from retail stores are way overpriced. If you live in the US I believe monoprice.com are great. Also in the US, in the unlikely event your cable really does cause problems at the current time you can even send it to the HDMI organisation for a replacement [1]. Outside of the US, either check local auction sites or just buy it from something like dealextreme.com (which ships from China so you will have to wait). If it really does cause problems, you should be able to RMA it. Nil Einne (talk) 13:22, 20 October 2009 (UTC)[reply]

Error message @ 6pm every day

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Hi! Every evening, at 6pm precisely (by my Windows XP computer clock), I get this error-message. I once installed a trial version of that program, and then uninstalled it very soon afterwards, and the folder listed (Pareto.....) doesn't exist. Does anybody know what I can do about this? Thanks! ╟─TreasuryTagsheriff─╢ 17:14, 18 October 2009 (UTC)[reply]

I would guess that the software set up a Windows Scheduled Task to run at 6pm every day, and it didn't bother tidying up that loose end in the uninstallation process. There are instructions here for removing it which might be helpful to get rid of it. --Kateshortforbob talk 17:24, 18 October 2009 (UTC)[reply]
The trial program may have installed a task-schedule event (to run some routine task, like updating itself) at 6pm. Its uninstaller should have removed that too, but it maybe it hasn't. The program to manage these tasks is called "Scheduled Tasks" - on XP it's in start->accessories->system tools; I think it's in the control panel on Vista. It shows a list of tasks and when they run; I think you'll find a 6pm listing that tries to do something with Pareto; if you delete that, it should fix your problem. But be careful in there deleting stuff you don't recognise, as some important (if routine) system functions may be listed too. -- Finlay McWalterTalk 17:23, 18 October 2009 (UTC)[reply]
Brilliant. Thank-you very much indeed! ╟─TreasuryTagCaptain-Regent─╢ 17:26, 18 October 2009 (UTC)[reply]

Hard disk problem?

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I've just installed a new graphics card (Sapphire Radeon HD4670), motherboard (ECS GeForce 6100pm-m2) and processor (AMD Athlon II x4 620) on a 3 year-old computer. The hard drives (SATA, one with Vista installed, one for data) remained the same. When starting up, I'm getting a STOP 0x0000007b (0x80399BB0, 0xC0000034, 0x00000000, 0x00000000) every time I switch on, either after a few seconds of the progress bar (when I start Windows normally), or after loading a couple of screens of drivers (in safe mode). Running startup repair from the DVD reports all tests completed successfully, and suggests an unidentified change to the system configuration (!). System restore doesn't make a difference. I suspect the problem could be driver-related or possibly disk corruption, as the machine kept shutting itself off before I put in the new parts. Is it worthwhile re-installing Vista, or is there another option I'm missing here (very possibly)? I've already tried chkdsk. Something slightly odd, which may be unrelated: the BIOS, American Trends (which seems a little quirky) shows my hard drives as 3rd and 4th master when booting, instead of 1st and 2nd, as I would expect. Of course, possibly that's completely normal. --Kateshortforbob talk 17:16, 18 October 2009 (UTC)[reply]

Making a change of this magnitude normally means that Windows will no longer run - it won't have the drivers for the motherboard, the processor or the graphics card. Unless anyone else can suggest a magic cure, installing Vista from scratch may be the best option.--Phil Holmes (talk) 18:20, 18 October 2009 (UTC)[reply]
Thanks, Phil Holmes. I thought that might be the case, but I was hoping I would get away with it! I should have curbed my amibiton and stopped with the graphics card. Of course, the really annoying part is that if I'd been patient and waited a week, I'd have had Windows 7 and a new HDD, and would have avoided this whole problem :-/ --Kateshortforbob talk 20:30, 18 October 2009 (UTC)[reply]
It has been my experience that unless you are installing the EXACT same make & model of motherboard, you will always need to reinstall Windows. 218.25.32.210 (talk) 05:40, 19 October 2009 (UTC)[reply]
I've had this problem before with XP. Haven't had it since I upgrade to Vista. However unless things have changed there are various ways to fix it particularly if you considered this before upgrading. Now that you have upgraded the simplest thing is probably a repair install. There should be many guides on the internet if you need further help. (E.g. from MS themselves although for XP [2]) Also you don't need the exact same make & model simply the same chipset & it will usually be fine Nil Einne (talk) 13:27, 20 October 2009 (UTC)[reply]
218.25, I had generally thought that to be the case, certainly up to XP, but I thought Vista might be a bit more flexible about these things.
Thanks for the interesting link, Nil Enne - i didn't realise that would work. Sadly, I didn't put much forethought into the process, so I've resigned myself to waiting a few days and going straight to the new OS when it arrives (possibly early). Still, it's given me the chance to upgrade a few other bits and pieces while I'm at it (including a new chipset!) --Kateshortforbob talk 11:00, 21 October 2009 (UTC)[reply]

How do I install Rebol/view on Win XP?

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The website for Rebol says that installing it is very easy, but does not actually tell you how to do it. I've downloaded it, run the program, filled in some details, clicked the Console icon and got a Rebol window to appear. But when I close this window, Rebol appears to disapear completely - in other words it has not been installed. What is the proceedure to follow to get a Rebol shortcut on the Programs menu and hopefully an icon on the desktop as well please? I'm also wondering where the user programs would be stored - I thought it was supposed to ask me where I wanted them, but has not done so. By bitter experience I know that its a point of honour among language creators to Never Never Never tell the public the most obviously needed information, but could someone break the code of silence please? 78.151.108.233 (talk) 17:56, 18 October 2009 (UTC)[reply]

Have you followed the quick start instructions from their website? -- kainaw 20:21, 18 October 2009 (UTC)[reply]
I feel that it is appropriate to restate my earlier comment about this (since this appears to be a question by the same OP). "Rebol is far less common (than python), so you will have a harder time tracking down references, resources, and fellow humans who can help you with conceptual and technical issues. Python has an enormous user-base." You might want to keep this in mind as you begin to invest time learning the language. It looks like the official Rebol Documentation is available online, but in my opinion it looks like there's a few orders of magnitude less information available than other common languages. ~ 70,000 Rebol Tutorial web hits vs. ~ ~ 5 Million Python tutorials vs. ~ 70 million C tutorials. By sheer statistical likelihood, your best bet of finding help with a specific problem goes up if you use a more common language. Nimur (talk) 00:38, 19 October 2009 (UTC)[reply]

I had not seen the Quick Start page linked to above, but it still does not say anything about getting Rebol on your start/programs menu. I shall run though it when I have more time.

If with Rebol I can program more quickly and (as a beginner/casual user/dilletante) do more things than with Python because they are not too difficult for me, then I'm for Rebol. That is all that matters. If everyone stuck with programs having the largest amount of users then we'd still all be using GWBasic, or assembler. 78.151.114.229 (talk) 09:41, 19 October 2009 (UTC)[reply]

I feel you are underestimating yourself with the "too difficult for me". Scripting (with python) isn't black magic in 2009, everything becomes easy once you read the documentation. But of course _the best_ is a matter of opinion. --194.197.235.240 (talk) 11:46, 19 October 2009 (UTC)[reply]
The Windows start menu belongs to Windows. It does not belong to Rebol. Therefore, I find it a bit silly to demand Rebol to explain how to use the Windows start menu. That is something that Microsoft should do. And, not surprisingly, it isn't hard to do. -- kainaw 12:12, 19 October 2009 (UTC)[reply]

System32 corrupt/missing

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The other day I saw this message:

“Windows could not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SYSTEM – You can attempt to repair this file by starting Windows Setup using the original Setup CD-ROM. Select "r" at the first screen to start repair."

The computer was perfectly fine in the morning; there was construction being done in the house during the day, and the power had to be shut off briefly, and when it was turned back on, that's the message that came up on the computer. I don't know if that has anything to do with it, but nothing else changed. Why would system32 just suddenly become corrupt? (This is in XP Professional, by the way).

The CD-ROM doesn't do anything, since Windows can't load up in order to read it. Is there another way to fix this? More importantly, is there a way to fix this without losing all the files on the computer? And should I not attempt to do so myself, since I know nothing, but rather have a professional do it? Adam Bishop (talk) 18:27, 18 October 2009 (UTC)[reply]

They want to you to boot with the install CD (rather than the broken windows install); you may need to change the boot-device-order in the BIOS to get this to work. -- Finlay McWalterTalk 18:30, 18 October 2009 (UTC)[reply]
Ah...how do I do that? And if I manage to repair the file, what will happen to everything on the computer? Adam Bishop (talk) 18:39, 18 October 2009 (UTC)[reply]
When your computer starts up, there should be a screen that tells you what key to press to access setup (i.e., BIOS) or a boot menu. It's the first screen that appears when your computer starts. The key you press depends entirely on the model of your computer.--Drknkn (talk) 19:11, 18 October 2009 (UTC)[reply]
Maybe normally, but the first screen that appears now is this "missing or corrupt" message... Adam Bishop (talk) 15:49, 19 October 2009 (UTC)[reply]
Before that screen appears, there should be a quick flash of a blue (or black) screen which gives you the opportunity to go into BIOS setup. (I assume you have already tried switching on with the original CD-ROM in place.) If this screen has been suppressed, you need to try holding down the different possible keys as you switch on. Do you know anyone with the same model of computer? The key to use varies according to manufacturer. It is usually F1, F2, or DEL, but sometimes ESC or F10. Dbfirs 17:16, 19 October 2009 (UTC)[reply]
Aha, thanks, it was F1, so I was able to change the boot order and now I can access the recovery system on the CD-Rom. I'm still reluctant to do anything though...this will just repair the corrupt file and leave everything else alone? It won't delete everything else on my computer? For some reason I'm paranoid that this is akin to formatting the hard drive. Adam Bishop (talk) 02:14, 20 October 2009 (UTC)[reply]
I'm still wondering what brand of computer you have. It'd save us a lot of typing if we knew. Also, is this CD made by the manufacturer? I've seen those format hard drives. If it's from Microsoft (without any mention of the manufacturer), it won't do anything of the sort (unless you select the option to format).--Drknkn (talk) 02:19, 20 October 2009 (UTC)[reply]
I don't remember what brand; it's made in Canada so probably MDG, but I'll check (I'm not at home at the moment). Otherwise it's just a regular PC. The CD is from Microsoft. Adam Bishop (talk) 02:25, 20 October 2009 (UTC)[reply]
Here are the instructions: [3]. If the screen you see upon booting from the CD doesn't look like the screen in the video, then the CD is not from Microsoft.--Drknkn (talk) 03:39, 20 October 2009 (UTC)[reply]
Same screen. The computer (at least the shell of it) predates XP anyway, so we couldn't have got it from the manufacturer. Adam Bishop (talk) 04:22, 20 October 2009 (UTC)[reply]

IE8 tab colours?

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Our machines at work have just been upgraded to IE8, and I've noticed that the tabs now change colour - sometimes they're yellow, sometimes they're blue, sometimes they're green, sometimes they're the standard plain grey. This may be an obvious question, but what do the colours mean? There doesn't appear to be any correlation between the colour and the nature of the page being displayed, that I can deduce, at least. Tevildo (talk) 20:05, 18 October 2009 (UTC)[reply]

Tabs of the same color are in a "group". What can you do with a group? All I know is close all tabs of a group at once. As for individual tabs, you can add them to a group or remove them from a group if you like. -- kainaw 20:18, 18 October 2009 (UTC)[reply]
I think they just indicate that one page opened the other page. For example, if you click a link on one page and a tab opens, the color indicates this happened.--Drknkn (talk) 20:20, 18 October 2009 (UTC)[reply]
See IE8 Tab Grouping from Microsoft's MSDN blogs page. Nimur (talk) 00:41, 19 October 2009 (UTC)[reply]

Thanks for the info. Tevildo (talk) 18:11, 19 October 2009 (UTC)[reply]

Screen flicker

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I was reading the article Life Story on Firefox when I realized that the Firefox window was flickering. It only flickered when my mouse pointer was in the actual article, not when it was pointing at a tab or the address bar. It also didn't flicker in any other tab. I couldn't reproduce the phenomenon upon closing and reopening Firefox.

What's responsible for this glitch? I realize that I'll probably never know, but I'm asking just in case anybody here experienced something similar. --99.237.234.104 (talk) 20:56, 18 October 2009 (UTC)[reply]

Sounds like typical Firefox flakiness. If it happens again try turning off Javascript. 66.127.54.181 (talk) 23:26, 18 October 2009 (UTC)[reply]
I use Firefox, and I've never had that sort of problem. If this was the only time it has happened, and it never happens again, it's tough (and perhaps unnecessary) to figure out and cause. If it recurs, you might want to think about the add-ons you have installed and enabled. And it always makes sense to use the latest stable release (for Windows, 3.5.3 if I'm not mistaken). By the way, when you post this kind of issue, it's good to mention things like the version you're running, what OS, etc. –RHolton00:37, 19 October 2009 (UTC)[reply]

DNS problems

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For some reason I've been having persistent DNS trouble, heavily for the past few days, but intermittently over a much longer period. Basically my existing connections will stay active, but DNS lookups will go very slowly or time out, with the outages lasting for a minute or so at a time. My ISP is AT&T; is this a familiar problem? Is it likely to be a configuration problem at my end? I'm thinking of installing a caching DNS proxy like Pdnsd -- does that sound like a good countermeasure? I'm mostly just web surfing and mostly just a handful of sites. 66.127.54.181 (talk) 23:24, 18 October 2009 (UTC)[reply]

The very first thing I'd try is to start using OpenDNS. If you really are having problems with your ISPs DNS server, that should solve it. It's very easy to configure your computer to use it (you don't have to install anything), and their website have very good guides on how to do it. 83.250.228.169 (talk) 00:29, 19 October 2009 (UTC)[reply]
I second OpenDNS —Preceding unsigned comment added by .isika (talkcontribs) 14:13, 19 October 2009 (UTC)[reply]

Both the above suggestions are shockingly bad advice. You should contact your ISP's help-desk if you believe this is a service issue (as it could be affecting other users). More likely this will be due to some issue with your computer (or local area network), which your ISP's help-desk may be in a better position to assist you with. The first questions which spring to mind are: Have you replicated this problem on another computer? What firewall / anti-virus software are you using? Do you use a router, and if so what make, model and firmware version? On an unrelated note: make sure to check out the Privacy and Terms of Service documents for OpenDNS if you consider using it.