Wikipedia:Reference desk/Archives/Computing/2009 July 28

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July 28

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downloading all torrents with wget

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So I want to download all of the torrents on The Pirate Bay with wget. I thought this would be a good command:

wget -N -r -l inf --no-remove-listing -A torrent http://thepiratebay.org

also equivalent to

wget -m -A torrent http://thepiratebay.org

It only gives me this:

--18:03:43-- http://thepiratebay.org/index.html => `thepiratebay.org/index.html' Resolving thepiratebay.org... 192.121.86.15 Connecting to thepiratebay.org|192.121.86.15|:80... connected. HTTP request sent, awaiting response... 404 Not Found 18:03:44 ERROR 404: Not Found.

Removing thepiratebay.org/index.html since it should be rejected. unlink: No such file or directory

FINISHED --18:03:44-- Downloaded: 0 bytes in 0 files

Is this because TPB has blocked wget? Why won't it work? :( Mac Davis (talk) 00:43, 28 July 2009 (UTC)[reply]

TPB, like many sites written using PHP, uses index.php, not index.html. Indeterminate (talk) 01:14, 28 July 2009 (UTC)[reply]
Are you sure this is a good idea? If I'm reading the front page correctly, there are over 2 million torrents on the site. Exxolon (talk) 01:22, 28 July 2009 (UTC)[reply]
Yes, after your HDD gets overfilled, catches on fire, and a skull-and-crossbones flashes on your screen, come tell us how it went. ;) [flaminglawyer] 01:34, 28 July 2009 (UTC)[reply]
Further... wget will not download the data. It will download the torrent file - a file which you use with a torrent program to download the data. In other words, you will end up with millions of torrent files. By the time you attempt to use them, most will be stale and worthless. -- kainaw 01:55, 28 July 2009 (UTC)[reply]
He probably wishes to make a competing tracker site and jump-start it by ripping TPB's entire database. APL (talk) 15:37, 28 July 2009 (UTC)[reply]

Problems with MSN Audio

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I live in Toronto, and used to have video calls with relatives in China with MSN Messenger. Despite the long distance involved, it worked perfectly. However, for apparently no reason whatsoever, the audio stopped getting through two weeks ago; MSN Messenger would take one-second recordings from my relatives' computer and repeat them over and over again. If they say the sentence "It's a lovely day today", I might hear the word "it" repeated several times before hearing the same thing with "today".

Both me and my relatives are able to have video calls with friends in the same city with no problem. Neither of us use Windows XP (which is known to cause choppy audio), and as far as I can tell, there have no changes in the speed of our Internet connection. What might be the problem? --Bowlhover (talk) 03:04, 28 July 2009 (UTC)[reply]

Problem with CLASSPATH

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  Resolved

Hello! I've been working on a Java swing program with NetBeans that uses several ImageIcons that I have created with the NetBeans GUI builder. When I run the program in NetBeans, it works fine, but now I want to distribute it as a .jar file and am having a lot of trouble. I get a java.lang.ExceptionInInitializerError-->NullPointerException that, according to the stacktrace, seems to be caused by not being able to load the files for the ImageIcons. Here's how my project looks:

My NetBeans project/.jar file:
|-->Map (package with all my .class files)
|-->images (package with half of my files for ImageIcons)
|-->photos (package with the other half)

Can I fix this problem by altering the MANIFEST file? What exactly do I put for the argument after the "class-path:"? Is there a better way to do this? I'm going to distribute it to people who have little experience with computing, so I need the execution of the program for them to be as simple as a double-click. I'll appreciate any help or suggestions. Thank you!--el Aprel (facta-facienda) 03:35, 28 July 2009 (UTC)[reply]

Boy, do I feel stupid! After several hours wasted, I fixed my own problem, and it turns out that I had saved my images as .JPG files, not .jpg files, which doesn't mean anything different to any computer running any OS...but does make a difference for the JVM. Java's case sensitivity applies even to its getResource() method. It hadn't occurred to me that that could have been causing the problem because I thought I had done file I/O and that wasn't case sensitive. Guess the java.io classes call the OS to do the work and get the file, and the OS isn't case sensitive, but Java must handle getting its own resource and uphold case sensitivity. Learn something every day.... I still don't understand why it ran fine in NetBeans even with the wrong case, but at this point, I'm just happy I got the .jar to work.--el Aprel (facta-facienda) 22:38, 28 July 2009 (UTC)[reply]
It is certainly possible to put the images in the JAR file. JAR files are intended for both .class binary and resource (e.g. images, audio) distribution. Can you printStackTrace() on the error, and post the results? (That might actually hint you in the right direction anyway). Probably the issue stems from some relative path issue; also look at Sun's Java guide for accessing resources in JAR files. Nimur (talk) 22:37, 28 July 2009 (UTC)[reply]
Specifically - here's the Retrieving Resources from JAR files guide. Nimur (talk) 22:39, 28 July 2009 (UTC)[reply]
Some operating systems do use case-sensitive file names. NetBeans uses the operating system's file handler (because the development SDK is not running entirely inside the JVM), but the deployed program by necessity must use the Java JAR resource manager (because it must do so from the bytecode and be platform portable). Case-sensitive filenames (especially extensions) are a common source of "lost" resources and mysterious "it worked over there five seconds ago!" bugs. Nimur (talk) 16:43, 29 July 2009 (UTC)[reply]
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hi,

i need MO/MT call related information as i am preparing for interview.please help me in this regard. —Preceding unsigned comment added by Sudcool2009 (talkcontribs) 07:15, 28 July 2009 (UTC)[reply]

java programming

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a program implementing an atm to help security of an institution sign students laptops into and out of the school compound —Preceding unsigned comment added by Qcush (talkcontribs) 12:21, 28 July 2009 (UTC)[reply]

When would you like that done by? --Sean 13:36, 28 July 2009 (UTC)[reply]
How could an ATM sign laptops out of a compound? What exactly is your question? Do you need help finding such a program, or designing such a program? Nimur (talk) 22:15, 28 July 2009 (UTC)[reply]
This program will "sign students laptops into and out of the school compound". I hope this is what you wanted. « Aaron Rotenberg « Talk « 16:03, 29 July 2009 (UTC)[reply]
Ask a stupid question, get a stupid answer
package ar.tools;

import java.io.UnsupportedEncodingException;
import java.security.*;

import javax.crypto.*;

import sun.misc.BASE64Encoder;

/**
 * This program will create a digital signature for the literal string
 * "students laptops into and out of the school compound".
 */
public final class DigitalSignature {
	private DigitalSignature() {
	}

	private static final String MESSAGE =
			"students laptops into and out of the school compound";

	public static void main(String[] args) throws NoSuchAlgorithmException,
			UnsupportedEncodingException, NoSuchPaddingException,
			InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
		System.out.println("Message:");
		System.out.println(MESSAGE);
		System.out.println();
		
		BASE64Encoder encoder = new BASE64Encoder();

		KeyPairGenerator asymmetricKeyGenerator =
				KeyPairGenerator.getInstance("RSA");
		asymmetricKeyGenerator.initialize(512);
		KeyPair keyPair = asymmetricKeyGenerator.generateKeyPair();

		System.out.println("Public key:");
		System.out.println(encoder.encode(keyPair.getPublic().getEncoded()));
		System.out.println();

		byte[] rawMessage = MESSAGE.getBytes("utf8");
		MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
		messageDigest.update(rawMessage);
		byte[] messageHash = messageDigest.digest();

		System.out.println("Message hash:");
		System.out.println(encoder.encode(messageHash));
		System.out.println();

		Cipher messageHashCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
		messageHashCipher.init(Cipher.ENCRYPT_MODE, keyPair.getPrivate());
		byte[] messageHashCiphertext = messageHashCipher.doFinal(messageHash);

		System.out.println("Digital signature:");
		System.out.println(encoder.encode(messageHashCiphertext));
		System.out.println();
	}
}

XP SP 2 OR SP 3 (SP2 is not updating)

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I have just upgraded my pc but confused with XP SP 2 and 3. Which one I should I choose? Another thing is XP SP 2 (version 2002) is not taking any update (Though update is on) in my new system. But it took lot of updates in my old system. Why this is happening? —Preceding unsigned comment added by 119.30.36.53 (talk) 12:29, 28 July 2009 (UTC)[reply]

I think you need SP2 before you can get SP3, as far as I know you should get all, since they include bug fixes.
Start here http://support.microsoft.com/kb/936929 (check the prerequisites section for issues)
Just to save you time - if windows update is not working for you , you can get SP3 via a direct download here http://support.microsoft.com/kb/322389
Question - what's going wrong with 'windows update' is it not starting at all? does it go to the web page, or further than that? Have you checked that it is set to update at a time the computer is on etc? Have you already got SP2 installed.83.100.250.79 (talk) 12:51, 28 July 2009 (UTC)[reply]
You should definitely update to Windows XP SP3. There are many bug fixes, security updates, and feature updates involving Windows Firewall, among other things. The reason that on your system, Windows Update completed its cycle and said that your system is up to date even though it didn't download any fixes is that all of the Windows Update updates that have been created by Microsoft for the last couple of years have required SP3. Tempshill (talk) 14:34, 28 July 2009 (UTC)[reply]
Actually windows update should automatically install SP3 as well - which makes me think that windows update is going wrong - as it often does to me.
Curiously I just tried windows update and 'hey presto' I find that there is a high priority update to download and instal - which windows update has not told be about either - makes me even more suspicious that something might be (temporarily) wrong with windows update itself
To the OP - if the update gets stuck on the update page, just try again in 5 mins, and try pressing refresh (F5) as well - I would guess that providing updates to x billion computers occasionally causes server issues...
If that's not happening/working please tell how far you can get when trying to update eg when you visit http://windowsupdate.microsoft.com/ what happens?83.100.250.79 (talk) 17:19, 28 July 2009 (UTC)[reply]
They're separate and individual. One is not 'better' than the other. In order to use 3, you have to have either 1a or 2 already installed. There's no reason not to have all three; 3 is not an improved version of 2, they are completely different programs. HalfShadow 22:11, 28 July 2009 (UTC)[reply]

Answers: [1][2] also look at http://www.google.co.uk/search?q=does+sp3+improve+performance&hl=en&start=10&sa=N for more results.83.100.250.79 (talk) 13:38, 29 July 2009 (UTC)[reply]

Fujitsu laptop...possibly dead

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My laptop has had a tendency of late of only working when plugged in to the mains, which is fine. Except last night when I loaded up as normal only to be greeted with my desktop full of "interference" and broken imagery. In a state of mild panic I unplugged the battery from the latop, following which the laptop duly died.

From last night onwards, I can turn the machine on - the on light is functioning and the DVD drive "clicks" to suggest it is being checked as per a normal process. From this point the thing doesn't go any further - no screen activity, no futher boot-up activity, no encouraging whirring noises, nothing.

Has my laptop passed on to the great customer advice centre in the sky, or is there something (anything?) I can do to solve what's gone wrong?

Many thanks in advance.....80.193.130.5 (talk) 13:41, 28 July 2009 (UTC)[reply]

It's most likely the motherboard or video card that's died. If you know how, or if you take it to a computer shop, you can probably get the data recovered from the hard drive. But if it's more than a year or two old, fixing the laptop itself might cost more than a new one. Indeterminate (talk) 01:53, 30 July 2009 (UTC)[reply]

Programming mouse buttons

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How can I program my extra mouse buttons so taht pressing them will be the same as pressing a couple of keyboard buttons one after the other? So instead of pressing say, 2-b-b-1, I can just press the extra mouse button and it will be as if I pressed those buttons in that order? —Preceding unsigned comment added by 92.251.255.11 (talk) 15:42, 28 July 2009 (UTC)[reply]

Some mice with programmable buttons come with software to do that and manage other settings. See if your mouse came with a CD containing this software, or check the vendor's website for a download. Xenon54 (talk) 22:34, 28 July 2009 (UTC)[reply]
You didn't mention an OS, but for Windows AutoHotkey is a useful free program that can reprogram your mouse buttons do practically anything. -- BenRG (talk) 17:00, 29 July 2009 (UTC)[reply]

Plucker and Ebook readers

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After the sad demise of Avantgo, I use Plucker and Sunrise to move online news articles and other content onto my Palm Tungsten E2. It takes a little effort, but generally works out. Can anyone tell me whether or not, and how (easily) Plucker-Sunrise content can be rendered and uploaded to a Sony PRS 505, or 700. My favorite app on the Ereader, I think, would be nytimes.com, economist.com, nameyourepublication.com...but I can't quite make out how those kinds of docs get onto that device. Thanks if you can advise. —Preceding unsigned comment added by 83.98.238.113 (talk) 18:11, 28 July 2009 (UTC)[reply]

Proxy

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I was just wondering if there is any website from where i can get free live proxies... or is there anyother way to change the ip address ... as there are some sites where i cant enter because of my location , so i was like if i get some proxies of other locations and i use them for my explorer ?? And could you guys please guide me too , how to use proxy IN a proper right way ? Thanks in advance —Preceding unsigned comment added by 202.147.172.236 (talk) 21:44, 28 July 2009 (UTC)[reply]

How about Tor? It seems like that would simplify things a bit. --98.217.14.211 (talk) 22:10, 28 July 2009 (UTC)[reply]
Surely the original poster is not seeking to circumvent an impending IP block for his numerous vandalism efforts? Several warnings on the talk page seem to have had no effect. If you continue to vandalize Wikipedia as you did this morning, and on other earlier occasions, you can be blocked; and we're pretty good at figuring out you've come back with a new IP. Nimur (talk) 22:19, 28 July 2009 (UTC)[reply]
Tor is the standard for this, and, as Nimur is probably right, I'll note that Wikipedia doesn't allow editing from Tor proxies, or any other open proxies ... so I wouldn't waste your time, OP. Tempshill (talk) 23:53, 28 July 2009 (UTC)[reply]

I didnt get u guys.. what is Tor ?? is it also some form of proxy or what ? —Preceding unsigned comment added by 202.147.172.236 (talk) 15:13, 30 July 2009 (UTC)

If you read Tor like the first reply suggested, you will see all. Technicalities aside, it works like a proxy. You install the Vidalia software, and you can get a plugin for firefox to help you use it. 86.17.139.211 (talk) 22:51, 30 July 2009 (UTC)[reply]

I'm sorry, 98 was right. I mean Tor (anonymity network), not Tor, which is obviously the wrong article.86.17.139.211 (talk) 11:07, 31 July 2009 (UTC)[reply]

When a computer was first activated

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Is there any way to tell from your PC's files alone what date your computer was first activated? I checked the dates for the HDD and keyboard drivers, and both said 6/21/2006, which seems mostly accurate to me. However, I did this on another computer (bought about 8 months ago) and got the same results.--The Ninth Bright Shiner 22:36, 28 July 2009 (UTC)[reply]

That's unfortunately when the file system claims the file was created or modified. It does not mean that the computer that the file now resides on was active at that time. File-systems have varying conventions about reporting create-, modified-, and last-accessed- times. Many of the system files on my Windows XP machine all show create-times from before my computer ever existed (because when those files were copied from the install CD, they carried over the create- and access- times from the Microsoft developer's environment where they were actually compiled). Even if the file shows an access time for the true, correct date and time it was put on to the hard-drive, that only tells you when the hard disk drive was active - it tells you nothing about the motherboard, CPU, RAM, etc. Your harddrive could have been programmed by an OEM in a separate machine designed for pre-loading disk images, and then placed into your current system. Nimur (talk) 22:44, 28 July 2009 (UTC)[reply]
There may be a install date buried somewhere deep in the registry. I know, for instance, that there's a reboot counter, which might provide some interesting background. But I would suggest looking at user creation dates, most of all for the administrator user, but also for any non-admin users (most people won't delete the original account), and use that in connection with other created dates on the computer to get a pretty good idea of the first install. Also, you might be able to dump the NTFS headers and see when the filesystem was created. I don't remember for sure, but I think NTFS stores this information somewhere. There are other quirky ways you could probably figure this out, but try those few things and let me know if it works. Shadowjams (talk) 07:12, 29 July 2009 (UTC)[reply]
If you want to know when the operating system was installed, I think you can look at the creation time of certain folders. For example, on my Windows XP computer, the Windows, Documents and Settings, and Program Files folders in the C: drive all have very similar creation times which seem to correspond to when the OS was installed. --Bavi H (talk) 00:34, 30 July 2009 (UTC)[reply]
If you run systeminfo, one of the things it'll tell you is "Original Install Date". Handy little tool. Comes with everything since XP by default. Indeterminate (talk) 01:45, 30 July 2009 (UTC)[reply]
I'm not so good at command prompt, so I could use just a teensy bit more help. >_< I did run systeminfo, but the only relevant date I could pull was 8/20/2007, which does happen to be when I installed Vista. A clean install, by the way. Would a clean install prevent me from learning the true date?--The Ninth Bright Shiner 19:39, 30 July 2009 (UTC)[reply]
Ah, yes, you did it right, but if you did a clean install, then all the previous dates and things on your hard drive would have been erased. There's not generally any way to find out when previously installed versions of Windows were activated. :) If you bought it from an OEM like Dell or something, you could probably call tech support and ask them. They could probably at least tell you when it was put together. Indeterminate (talk) 01:45, 31 July 2009 (UTC)[reply]
I thought as much. :-( Well, 21 June 2006 sounds accurate enough, but I guess I'll never quite know the truth. Systeminfo does seem interesting though, so thanks anyway!--The Ninth Bright Shiner 23:43, 31 July 2009 (UTC)[reply]
  Resolved...kind of.