Wikipedia:Reference desk/Archives/Computing/2007 November 6

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November 6[edit]

Odd website[edit]

Hi all,

I recently came across this cached website: http://72.14.253.104/search?q=cache:MLQKinzVpMIJ:special.sword-desk.nl/1/50.html+%22%22&hl=en&ct=clnk&cd=16.

What on earth is the purpose of it? It looks like it has just taken random sentences/words from the internet and stuck them together, my favourite line in it has to be "You address labels. address labels adaptation of squids". Why would someone create a bot to create a page like this!?

Aaadddaaammm 04:54, 6 November 2007 (UTC)[reply]

Perhaps some form of spamdexing? --Spoon! 05:05, 6 November 2007 (UTC)[reply]
Hmm, yea it does seem to have parallels with Scraper site, but there's no advertising on the site! All the links (as far as I can tell) point to further pages whose urls are very similar to this one (although all these links seem to be dead)... any other insights? Aaadddaaammm 05:12, 6 November 2007 (UTC)[reply]
A fun experiment? That would make epic bragging rights to show your friends that you wrote some script and now your page is on the top 10 google results --ffroth 05:19, 6 November 2007 (UTC)[reply]

Firefox "restore session"[edit]

I tried to start Firefox (2.0.0.9) from a previous session, but it keeps crashing after seemingly loading all my old windows. Is there some file on my system to which Firefox saves the URLs and window configurations so I can open the pages manually and try to sniff out the bad apple? --151.200.19.209 05:05, 6 November 2007 (UTC)[reply]

Dont use session restore. If you let firefox crash to much it might delete/corrupt all saved bookmarks/history/passwords/form info. —Preceding unsigned comment added by 24.250.139.137 (talk) 09:18, 6 November 2007 (UTC)[reply]

Yes, Firefox seems prone to corrupting bookmarks etc, I've had it happen about three times although the latest version seems more stable. When you start it, it should ask if you want to restore your previous session and start a new one, if you start a new one, you should be OK. The other thing that I find Firefox doesn't like is opening PDF files. Best to download them and read them in the standalone Acrobat Reader. GaryReggae 13:03, 6 November 2007 (UTC)[reply]

But what of my old windows? There were pages I wanted to read, and I'd rather not start hunting through my history for them... --151.200.27.252 13:39, 6 November 2007 (UTC)[reply]
In my experience, if 'Restore previous session' crashes Firefox, I start a new session and my last viewed pages have been added to History - Recently Closed Tabs. 86.21.74.40 14:40, 6 November 2007 (UTC)[reply]
If you know which tab crashes Firefox, you can try to close it as soon as it begins loading. If you don't know, you are out of luck. -- ReyBrujo 04:19, 7 November 2007 (UTC)[reply]

Have you tried loading Firefox in safe mode? It might be a misbehaving add-on for all I know ... ----Kushalt 04:28, 7 November 2007 (UTC)[reply]

Haywire - a new virus?[edit]

When I log onto certain news orgs or or other "legitimate" sites (like the New York Times) and a pop up ad or message tries to popup but gets blocked a system message will come up that says a device, etc. can not be accessed. Then when I click "OK" all hell breaks loose and blank web pages start popping up until memory is filled and the computer locks up. How can I stop this? Dichotomous 05:22, 6 November 2007 (UTC)[reply]

... it would help if you told us what browser and what operating system for a start --Dacium 06:32, 6 November 2007 (UTC)[reply]
If you had any knowledge to impart you would already know which browser and OS. Dichotomous 20:53, 6 November 2007 (UTC)[reply]
How can we know which browser version and which OS and its version? You are an ungrateful moron.--Dacium 05:17, 7 November 2007 (UTC)[reply]
If you were familar with the problem then you would already have this information. Pretending like you can solve a problem you are not familar with by asking for the browser version and OS makes you the moron. Dichotomous 13:57, 7 November 2007 (UTC)[reply]
And if you are worried about a virus or malware you should first try scanning for it. Try AVG or SpyBot if you don't have virus and malware scanners. --24.147.86.187 14:28, 6 November 2007 (UTC)[reply]
Had I not already scanned for a virus, malware or spybot there would be no point in posting this question here. Dichotomous 20:53, 6 November 2007 (UTC)[reply]
I'll take a guess at your OS - Windows XP, Service Pack 2, and browser - Internet Explorer 7. If these are incorrect, could you please correct me - unfortunately, my ESP is on the blink. Do you have an example of a page which is trying to open a pop-up? On the New York Times website, for example? I haven't been able to find any pop-ups there yet. Are the pop-ups legitimate NYT content, or spam advertising? What is the exact system message you are receiving? Have you tried running a Hijack This! log to check what is running on your system? Diagnosing a problem remotely is difficult - precise information would be useful. Thanks! --Kateshortforbob 12:13, 7 November 2007 (UTC)[reply]
It's actually Winx64 SP2 IE6, but you would most likely already be familiar with this if you were aware of the problem. It appears that whenever a site is accessed IE uses 2 browser windows instead of one. I think this is done on Winx86 SP2 IE6 as well in order to keep the link open or some other similar reason. In the case of Winx64 SP1 or SP2 IE6 or IE7 the second IE browser window is not hidden or minimized. When a web site component can not find hardware it wants like a sound card maybe or uses popups and is blocked or can't find the hardware it tries again by opening another pair of browser windows and has somehow not been prevented from doing this over and over again up to about 300 new windows. Its kind of like an absence of the routine that prevents more than one instance of a link coming up beyond the first one no matter how many times you click the link after the first. The problem is caused by the web site but not prevented by the IE or OS. Dichotomous 14:09, 7 November 2007 (UTC)[reply]
I'm familiar with those symptoms. On Windows 98 with Netscape 4.51 and Gozilla (the free version, not the commercial version), certain advertising JavaScripts (most often found on pornography and illegal software sites) will make Netscape crash with the effects you report. The cause is the way Gozilla's advertising functionality interfaces with Netscape; the solution is to uninstall Gozilla. A workaround is to stop using Netscape to look at pornography. --Carnildo 00:19, 8 November 2007 (UTC)[reply]
I agree that the New York Times should be rated as a pornographic site. Aside from this whenever you click on a Google news story and it turns out to be the New York Times you get a user ID and password screen. Only a pornographic site would require this of persons wanting to read a news report. But I'm curious about something else... someone told me that the hijack this reference above leads to a download designed to wipe out your hard drive. Is that correct? If so then the other things I've heard about the lack of integrity of the Wikipedia computing desk must be true. What can you tell me about this? Dichotomous 02:49, 8 November 2007 (UTC)[reply]
HijackThis is software that records programs and processes running on your computer. You can disable or remove most entries found if you are dubious about them. You can also upload the log file it produces to a web forum, where experienced and knowledgable users will be able to analyse it for you. HijackThis is owned by Trend Micro, a reputable security firm and is generally highly thought of. However, if the problem you are having is related to a browser bug, as you imply, HijackThis won't provide a solution. You could try blocking all popups, using another browser (Firefox, perhaps) or checking out the Microsoft site for a patch. If it's a known bug, there may well be a solution already. If it hasn't been reported yet, you can do the world a service and report it yourself. If you'd like to cast any further aspersions on my intelligence or lack of integrity, perhaps my talk page would be a more appropriate venue? -- Kateshortforbob 09:42, 8 November 2007 (UTC)[reply]
(re-indent, try using a resolution above 640x480) He was referring to earlier in his comment when he said "(most often found on pornography and illegal software sites)", not to your problem with the new york times. Also nobody's impressed by your insults. --ffroth 18:36, 8 November 2007 (UTC)[reply]
Interesting that somebody who created and continued this thread with an assumed identity diff 1, diff 2 would be worried about "lack of integrity". --LarryMac | Talk 19:12, 8 November 2007 (UTC)[reply]
Heh I'm so keeping that quote. If so then the other things I've heard about the lack of integrity of the Wikipedia computing desk must be true. OK OK you caught us, hijackthis is actually a virus. The entire internet has lied to you and is laughing behind your back right now. You should go download storm right away to clean your system. -_- (don't really) --ffroth 22:11, 9 November 2007 (UTC)[reply]

HDTV mpeg2 bit rate[edit]

What is the average bitrate for HDTV (1920x1080 5.1 audio) MPEG2 compressed terrestrial TV as transmitted for example in Australia? I have some HDTV receiver cards that I want to put into older PCs to save video to harddisk. I know that PCI is limited to about 533MB/second and my IDE harddisk is limited to just 133MB/second. Each card can decode 2 channels at once, but I wonder how many MB/second a single HDTV mpeg channel would be on average?--Dacium 06:09, 6 November 2007 (UTC)[reply]

Might have found the answer: MPG2 High Level is 1920x1152x30fps, and has a bit rate of 80Mb/s (10MB/second). So it should be possible to stream multiple channels at once, I was only hoping to do 6 channel to 3 different harddrives.--Dacium 06:14, 6 November 2007 (UTC)[reply]
That figure sounds a bit high; standard definition channels in the UK are only about 3Mbit/s. -- DatRoot 15:14, 6 November 2007 (UTC)[reply]
You will find the bottleneck of disk writing comes a LOT sooner than 133MB/sec, unless you are using a very very fast RAID setup. Practical streaming is 20-30MB/sec under perfect circumstances, even with the latest IDE disks. However, the bitrate of 80Mbit for broadcast HDTV is quite high. Using Australia's DVB-T (as an example) allows for at most 30 mbit per channel, but more likely 15 mbit or lower depending on station circumstances, which translates to a more manageable 2MB/sec stream. --Jmeden2000 16:16, 6 November 2007 (UTC)[reply]

Setting up a LAN[edit]

What would be a good hardware/software system for setting up a LAN that connects to the internet for a school of about 1,000 student with around 200-300 computer access points? As well, would the type of computer-Mac or PC-matter? Thanks. 71.18.216.110 14:36, 6 November 2007 (UTC)[reply]

The type of computer doesn't matter in any way. All it needs is a network adapter. You will need a gateway with DHCP running. That will be your connection to the Internet. Every computer will contact it to get to the Internet. Then, you can run the normal spiderweb of network cables to switches and set up wireless access points. There is nothing special or abnormal about it at all. There's no "good" hardware/software system either because there are so many alternatives. Technically, you could get a $50 Linksys router and run it through a bunch of switches - but it can only handle 253 computers (at a rather slow speed due to bottlenecking). -- kainaw 14:41, 6 November 2007 (UTC)[reply]

Search & replace => keep some of the text found[edit]

Hi all,

I've got a large number of web pages that include some text wrapped in now defunct div's: <div class="decrecated class">some text</div> .

I want to remove all those divs. I could easily use search&replace to remove the first half, but then I'd be left with a lot of hanging </div>'s, which I couldn't remove using s&r (because it would remove the ones I want to keep).

I know a little bit about using regular expressions in s&r, but is there any way to delete just a part of what you find, or to replace it with a piece of what you found? I'd like to say: "Search for '<div class="decrecated class">[TEXT]</div>', replace it with '[TEXT]'". Is anything like that possible?

Thanks!

Sam, 15:29, 6 November 2007 (UTC)

Yes. Regular expressions are the way to go. You'll want to replace something like "<div[^>]*>([^<]*)</div>" with "$1". The syntax of your editor may be different. The idea is to catch the part inside the div with parenthesis and then paste it back out using the $1. -- kainaw 15:35, 6 November 2007 (UTC)[reply]
Something to bear in mind is that regular expressions do not handle nested constructs. So, the case <div class="deprecated">bla <div class="foo">bar</div> bla</div> would not remove the outer, matching close tag, but would result in: bla <div class="foo">bar bla</div>. In addition, Kainaw's expression does not allow for any other tags in between. You might want something like: <div[^>]+class="deprecated"[^>]*>(.*?)</div>, thus making use of non-greedy matching.89.205.130.59 03:25, 12 November 2007 (UTC)[reply]
If you need to support nested divs, you probably need a proper HTML parser. Fortunately, it's a pretty common problem, so someone has probably already written one for you. What language did you say you were working in, again? —Ilmari Karonen (talk) 08:59, 12 November 2007 (UTC)[reply]

Restore copied over files[edit]

Daaamn! I have just been an idiot and copied html files from a ftp server over the files it had just taken me all day to update on my hard drive. Yes I inverted my 2 windows explorer windows, yes I should have used a proper ftp client, yes I'm an idiot. Please help is there any way to get the files back? Keria 15:42, 6 November 2007 (UTC)[reply]

Nope! Sorry 'bout that. Writing over a file is one of the almost sure-fire ways to render its data unaccessible (much worse than just deleting it, as it turns out, since the latter just flags is as free data that can be overwritten in the future). But if it makes you feel better it is happened to all of us at one point or another. --24.147.86.187 15:54, 6 November 2007 (UTC)[reply]
"Writing over" can mean two different things:
  1. Opening the file for read/write access and writing new data over what's already there.
  2. Opening the file for (over)writing.
The FTP program probably did the second; it would be very strange to do the first. This is similar to deleting the file and then creating a new one with the same name. There's a good chance that the old file's contents are still on the disk somewhere, since there's no particular reason for the filesystem driver to use the old file's clusters for the new file. However, the directory entry has most likely been overwritten, which means the simplest approach to undeletion won't work. You would probably have to search through the free space of the drive for relevant phrases from the files to find them. There are various free Windows programs that can help with this (e.g. HxD). -- BenRG 19:41, 6 November 2007 (UTC)[reply]

Ah typing through the flood of tears streaming on my keyboard (not really). I loaded all those pages to test them in Opera. Is there a memory of them somewhere? Keria 16:10, 6 November 2007 (UTC)[reply]

  • I have successfully retrieved lost data under Linux by simply copying /dev/mem to a file and searching for known text. Perhaps Windows has some equivalent feature? --Sean 16:31, 6 November 2007 (UTC)[reply]

Oh, if you loaded them in a browser, maybe, MAYBE! Make a quick copy of the cache directory (before it get overwritten or cleared) and search around inside it for text you know would be in that file. --24.147.86.187 17:50, 6 November 2007 (UTC)[reply]

Certain modern versions of Windows have Shadow Copy (also called "Previous Versions"), which, if you have it enabled, just might have stored a copy of your data before it was replaced. --89.205.130.59 03:45, 12 November 2007 (UTC)[reply]

Windows 2000[edit]

Hello, i have reinstalled windows 2000, downgrading from xp, as my laptop is from 2000, I formatted, and the thing is now clean, and runs beautifully. Thanks for all the help. I now have no sound. i have tied the start,settings, contol panel, sound options, hardware says the sound is installed and running fine, however, audio, the previous tag is all unuseable, unhighlighted. i have a dell latitude cpx. Thankyou again. —Preceding unsigned comment added by 82.3.149.242 (talk) 18:44, 6 November 2007 (UTC)[reply]

Go to http://support.dell.com and ensure you've installed the proper sound driver. -- kainaw 18:49, 6 November 2007 (UTC)[reply]

Mouse droppings?[edit]

I use a hard plastic mouse pad and an optical mouse. Every few weeks I notice that there are these little hard black spots on my mouse pad that need to be scraped or cleaned off. Is it the non-stick mouse surface rubbing off? What is it caused by and is there any way to prevent them? --24.249.108.133 21:49, 6 November 2007 (UTC)[reply]

They're the same thing that clogs up non-optical mice: skin oils, dirt, and other miscellaneous crud. The advantage with the optical mouse is that they'll just create less-slippery spots on the mousepad, they won't gum up the interior workings of the mouse.
Atlant 23:37, 6 November 2007 (UTC)[reply]
Yes, I find this too, I assume it must be gunk from your hands and dust GaryReggae 08:05, 8 November 2007 (UTC)[reply]

How would I network a computer using Windows 3.1.1[edit]

I need to get a working internet browser with online access for 3.1.1. What would be the easiest way to do that? The computer is an old pentium 3 compaq. I can post more specs if need be. —Preceding unsigned comment added by 24.117.137.182 (talk) 22:21, 6 November 2007 (UTC)[reply]

You'll need a working Winsock stack, and maybe an old old copy of Mosaic. I can't remember what other browsers might have been available way back then, and I was more of an OS/2 guy anyway. Are you going to use dial-up? --LarryMac | Talk 00:13, 7 November 2007 (UTC)[reply]
Ah no, 3.11 (which was "For workgroups") has an MS produced TCP/IP stack; the first version of Windows to do so. IE was available in the "Plus Pack", but there are still versions of IE, 5.01 floating about. --Blowdart | talk 08:19, 7 November 2007 (UTC)[reply]

No im using cable, i found a browser for it but i dont really know what winsock is? what does it do? —Preceding unsigned comment added by 24.117.137.182 (talk) 00:26, 7 November 2007 (UTC)[reply]

You can try to get hold of the trumpet winsock, a TCP stack for windows. This is a shareware that may or may not still be for sale. The winsock profides an interface for programs to do TCP IP, it has a library of procedure calls to make data travel on a network. It also has to interface to the low level holes in the computer to get the data in and out, such as the modem or ethernet driver. Graeme Bartlett 00:55, 7 November 2007 (UTC)[reply]
Winsock provides the TCP/IP networking functionality; I think we can safely assume that's the kind of networking you're looking for. But if not, you might want to also see Windows for Workgroups.
Atlant 00:55, 7 November 2007 (UTC)[reply]
Offtopic but why you need Windows 3.1? Pentium 3 isn't that old and Windows 98 will run comfortably on a Pentium 500Mhz, or even a Linux distribution like Xubuntu with wine will be able to run a lot of the windows programmes, and dosbox for dos programmes. --antilivedT | C | G 04:43, 7 November 2007 (UTC)[reply]
Used computers that will run Windows XP are getting very cheap (~ $300 on Craigslist). A newer machine might preserve your peace of mind. My memory is that networking on Windows 3.1 was a pain. Be prepared to do some user-unfriendly installation and deinstallation. You may need to find some old books to walk you through the setup. If you need to replace any hardware pieces they may no longer be available, or may not come with drivers for Win 3.1. EdJohnston 05:23, 7 November 2007 (UTC)[reply]

Forcing firefox to open[edit]

I don't know if this bug anyone else, but when I click on a hyper link in Thunderbird or Messenger it automatically opens in IE, which is downright annoying. Is there anyway to get FF to open automatically? Cheers Jackacon 22:59, 6 November 2007 (UTC)[reply]

Which version of Windows? On XP (SP2) there should be an item on your start menu called "Set program access and defaults" which will let you specify default web browser, email, media player and instant messenger programs. In addition, you might want to go to the Firefox Tools/Options/Main window and use the button at the bottom to check if Firefox is your default browser. --LarryMac | Talk 00:06, 7 November 2007 (UTC)[reply]