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September 27

Linksys WAP54G wireless access point help

This question concerns a Linksys WAP54G wireless access point. (Note that this is a simple access point, not a router.) I was attempting to set an access password (taking my leave from the legions of unsecured Linksys access points :-) ), but I ran into difficulties. I have two questions:

1. I had temporarily made a direct wired ethernet connection between my Mac and the access point. I had succeeded in accessing the configuration screens at http://192.168.1.245/. Confused about what it wanted for WEP keys, I clicked a "Help" button. It tried to open a new browser window (also on 192.168.1.245, presumably to display the help in), but the connection timed out. After that, the main configuration screen was also displaying a "can't connect" message. After that, no matter what I did, I could never never connect to 192.168.1.245, no matter what I did. (I tried resetting the access point, and everything.) Is there anything else I could try? Did the thing break, just when I hit the Help link?
2. After giving up on setting a password, I reconnected everything the normal way, and went back to browsing the net wirelessly (and unsecuredly). I idly tried hitting http://192.168.1.245/ again. To my dismay, it worked! And I was able to set a password, so my access point is now secured! But does this mean that anybody driving by could have taken control of my access point away from me, by setting passwords I didn't know? (Or did maybe the same thing that broke under #1 cause 192.168.1.245 to be accessible wirelessly only as it wrongly became inaccessible wiredly?)

I'm glad to have finally secured the thing, but I'm bothered that its default security model might have been even worse (much worse!) than I had thought... —Steve Summit (talk) 04:08, 27 September 2010 (UTC)

My Linksys router has a setting under Administration --> Management called, "Wireless Access Web" that lets you set whether people can administer the router wirelessly. I have it disabled. Check that to see if it's enabled. But if you were able to set the password wirelessly, then the answer to your question about wireless administration is obviously, "yes."

As for a password, it sounds like you set a password for the web interface, but haven't set a WEP or WPA key for connecting to the network? Bad move. People can still use your wireless connection and therefore intercept the password needed to login into the AP. WEP and WPA encrypt wireless traffic and prevent unauthorized people from joining your network. My router, by default, is accessed using HTTP instead of HTTPS, meaning the password is sent in the clear if WPA or WEP are disabled. Also, preferably, set a WPA2 key (not WPA or WEP). WEP is weak. WPA is better, but WPA2 is the best.--Best Dog Ever (talk) 04:30, 27 September 2010 (UTC)

Don't worry, I set both an admin and an access password. Thanks. (Still wondering about the suden lack of wired admin access, though.) —Steve Summit (talk) 12:05, 27 September 2010 (UTC)

How to Run Emacs Org Mode Commands From the Terminal?

I have a file, foo.org. When I open it in emacs, I can run C-c C-e b and get an html exported file, foo.html. Is there anyway to do this without opening emacs? I'm imagining something from the shell that looks like this:

emacs -orgmode -export -html foo.org > foo.html

Thanks if anyone knows the answer —Preceding unsigned comment added by CGPGrey (talk • contribs) 08:36, 27 September 2010 (UTC)

Short answer: Yes. It's Emacs! Longer answer: I know no simple way off-hand, but see the options --batch and --script in the Manual. --Stephan Schulz (talk) 09:15, 27 September 2010 (UTC)

I've gotten closer with this bit of script:

emacs -batch --eval '(progn (find-file "test.org.txt") (org-export-as-html "test.org.html"))'

But I'm still running into problems. The output "test.html" is blank, every time. I there is a problem with the 'find-file' part. How do I tell 'find-file' exactly where the source file is? --CGPGrey (talk) 10:15, 27 September 2010 (UTC)

I see two small problems: First, you export as" test.org.html", but you say "test.html" is empty. Secondly, I think it should be --batch (note two dashes). Moreover, do you possibly need to switch to orgmode? --Stephan Schulz (talk) 10:53, 27 September 2010 (UTC)

You were right about the single vs. double dash, thank you. The other bit was just my typo. Here's what happens now. I enter this command:

emacs --batch --eval '(progn (find-file "test.org") (org-export-as-html "test.html"))'

Emacs then spits out a .html file that looks like this:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
               "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"
lang="en" xml:lang="en"> 
<head> 
<title>test</title> 
<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/> 
<meta name="generator" content="Org-mode"/> 
<meta name="generated" content="2010-09-27 14:43:09 BST"/> 
<meta name="author" content="Grey"/> 
<style type="text/css"> 
 <!--/*--><![CDATA[/*><!--*/
  html { font-family: Times, serif; font-size: 12pt; }
  .title  { text-align: center; }
  .todo   { color: red; }
  .done   { color: green; }
  .tag    { background-color:lightblue; font-weight:normal }
  .target { }
  .timestamp { color: grey }
  .timestamp-kwd { color: CadetBlue }
  p.verse { margin-left: 3% }
  pre {
	border: 1pt solid #AEBDCC;
	background-color: #F3F5F7;
	padding: 5pt;
	font-family: courier, monospace;
        font-size: 90%;
        overflow:auto;
  }
  table { border-collapse: collapse; }
  td, th { vertical-align: top; }
  dt { font-weight: bold; }
  div.figure { padding: 0.5em; }
  div.figure p { text-align: center; }
  .linenr { font-size:smaller }
  .code-highlighted {background-color:#ffff00;}
  .org-info-js_info-navigation { border-style:none; }
  #org-info-js_console-label { font-size:10px; font-weight:bold;
                               white-space:nowrap; }
  .org-info-js_search-highlight {background-color:#ffff00; color:#000000;
                                 font-weight:bold; }
  /*]]>*/-->
</style> 
<script type="text/javascript"> 
<!--/*--><![CDATA[/*><!--*/
 function CodeHighlightOn(elem, id)
 {
   var target = document.getElementById(id);
   if(null != target) {
     elem.cacheClassElem = elem.className;
     elem.cacheClassTarget = target.className;
     target.className = "code-highlighted";
     elem.className   = "code-highlighted";
   }
 }
 function CodeHighlightOff(elem, id)
 {
   var target = document.getElementById(id);
   if(elem.cacheClassElem)
     elem.className = elem.cacheClassElem;
   if(elem.cacheClassTarget)
     target.className = elem.cacheClassTarget;
 }
/*]]>*/-->
</script> 
</head><body> 
<h1 class="title">test</h1> 
 
<div id="postamble"><p class="author"> Author: Grey
<a href="mailto:grey@Cobalt.local">&lt;grey@Cobalt.local&gt;</a> 
</p> 
<p class="date"> Date: 2010-09-27 14:43:09 BST</p> 
<p>HTML generated by org-mode 6.21b in emacs 23</p> 
</div></body> 
</html>

That is what I would get if I was exporting to HTML a blank org mode file. It turns out that no matter what I write in the (find-file "test.org") I'll get an HTML file the same as above, even if the stated org file does not exist. So clearly, the "find-file" part of the above is not working, but I can't figure out how to fix it. --CGPGrey (talk) 13:47, 27 September 2010 (UTC)

(-batch and --batch are equivalent, BTW.) If you write it like this, the file should be in the current directory, otherwise you have to specify the path. I don't have org mode installed to test it, but emacs -batch -eval '(progn (find-file "test.txt") (write-file "test2.txt"))' works as expected; you could try something like that to verify whether the problem is really with find-file.—Emil J. 13:54, 27 September 2010 (UTC)

tsql:sqlserver=plsql:oracle=?:mysql

t.i.a. --217.194.34.103 (talk) 13:31, 27 September 2010 (UTC)

It doesn't appear to have a name beyond "the extensions to, and subset of, SQL supported by MySQL". Not enough marketing types, I guess. --Sean 15:54, 27 September 2010 (UTC)

mac safari won't submit form

I do not have a mac, so I cannot easily figure this out. This page looks like a perfectly legitimate form to me, but mac safari will not submit it. Clicking the submit appears to do nothing at all (from what I've been told). Is there anyone with mac safari that can try it and, hopefully, see why the submit button is being completely ignored? -- kainaw™ 17:35, 27 September 2010 (UTC)

I tested it with Mobile Safari on an iPod touch, and that form has no submit box when viewed with it (it does in Firefox, so it does seem to be a browser issue). -- Finlay McWalter ☻ Talk 17:51, 27 September 2010 (UTC)

I suspect it's a browser compatibility problem because it's using <button type="submit">Submit</button> rather than <input type="submit" value="Submit"> If that's your website then changing it to the latter should work regardless of the browser (with the same visual appearance)  ZX81  ^talk 18:06, 27 September 2010 (UTC)

I have searched and I cannot find any reference that Safari won't handle <button type='submit>. There is a cross-browser issue with <input type='submit'> in the css area. You can style a button, but you can't style input-submit separately from the general submit on all browsers. -- kainaw™ 18:08, 27 September 2010 (UTC)

That's correct about the CSS styling, but the page in question isn't doing that hence my reply about it'll look exactly the same, but will work across all browsers (I don't know about Safari, but IE6 has problems with <button>) Given what Mr.98 has just written below though, moving the <form></form> and the initial <input> outside the would probably fix the problem regardless of whether input/button is being used.  ZX81  ^talk 18:27, 27 September 2010 (UTC)

Safari 5.02's error console throws the following when it loads the page:

*<form> cannot act as a container inside <table> without disrupting the table.  The children of the <form> will be placed inside the <table> instead.   contact.html:171
*<input> is not allowed inside <tbody>. Inserting <input> before the <table> instead.  contact.html:173

I don't know if that helps or not. It seems to submit on my Mac (the Submit button is there, and when I put in a nonsense name and no e-mail, it told me, after submitting, that it wanted an e-mail address, which I assume means it worked). --Mr.98 (talk) 18:18, 27 September 2010 (UTC)

That was the problem. Placed the table inside the form instead of the form inside the table and it works now. -- kainaw™ 18:41, 27 September 2010 (UTC)

I can confirm that Mobile Safari now sees the submit button and that it works okay. -- Finlay McWalter ☻ Talk 18:49, 27 September 2010 (UTC)

Thanks. I will have to keep in mind that some browsers don't like forms inside of tables. -- kainaw™ 18:53, 27 September 2010 (UTC)

Loose lines in LaTeX

Resolved

How (beyond \sloppy, which is often insufficient) does one persuade LaTeX to allow lines looser than it normally would so as to avoid overfull hboxes? (That is, persuade it to break the line before the offending word and justify the remainder, even when the result risks making rivers, rather than break it after and produce an overlong line even at the tightest spacing.) --Tardis (talk) 17:58, 27 September 2010 (UTC)

\sloppy works by setting \tolerance=9999, \emergencystretch=3em, and \hfuzz=\vfuzz=.5pt. You may try to make it even sloppier by manually setting bigger \emergencystretch. If you just need to tweak a particular piece of text by hand, you can insert \break at the desired break point.—Emil J. 18:07, 27 September 2010 (UTC)

Whilst this doesn't directly address your problem, it will probably do the job. Iff you're using pdflatex (it doesn't work for dvilatex), type \usepackage{microtype} in the top-matter of your document. It subtly adjusts font widths and other parameters such as to improve the appearance and readability of your documents, usually alleviating all your overfull boxes.--Leon (talk) 18:09, 27 September 2010 (UTC)

Interesting — looking forward to trying this.

Now, what I have often wished for is a way to convince LaTeX to break before the long word and not justify the remainder. In other words, tell it that I would rather have the text not get to the right margin rather than go past it. I don't mean putting \\ at the end of particular lines — I mean telling the algorithm "prefer underfull hboxes to overfull ones, and don't go stretching them beyond reason". Is there any way to do that? --Trovatore (talk) 08:20, 28 September 2010 (UTC)

The algorithm does prefer underfull lines to overfull ones, in fact, it treats all overfull lines as infinitely bad. "Stretching beyond reason" is what underfull means. What you describe is a sort of ragged right typesetting, whose basic form can be done in LaTeX with \raggedright. It works by making \rightskip infinitely stretchable; if it's too ragged for you, you can instead give this parameter small finite stretchability, such as \rightskip=0pt plus 5pt. However, I don't think there is a way to tell the algorithm to right-justify as usual when possible, and only rag lines that would be too bad otherwise.—Emil J. 11:35, 28 September 2010 (UTC)

That's too bad. That last thing is exactly what I was looking for. --Trovatore (talk) 17:39, 28 September 2010 (UTC)

But wait, if ovrfull lines are infinitely bad, does that apply even to lines that contain an \mbox? It wasn't really a word that I wanted it to put on the next line, leaving the previous line ragged. It was something in an \mbox. I never did figure out how to do it. --Trovatore (talk) 17:40, 28 September 2010 (UTC)

That doesn't make a difference, I'm afraid. The algorithm treats words and boxes pretty much the same (except that words can be hyphenated). However, the way you describe it it sounds like a one-off thing, why can't you use \\ then?—Emil J. 11:26, 29 September 2010 (UTC)

Well, that particular example was years ago, but if I had changed text above that line, it might have become wrong. I wanted a solution robust against such change.

But if boxes are the same, then I don't understand why it ran over the right margin, rather than putting the box on the next line even at the cost of absurdly stretching text in the current line. --Trovatore (talk) 17:58, 29 September 2010 (UTC)

Because stretching text too absurdly will also make its badness infinite (or at least exceed the \tolerance), and then it's all equal to TeX (or rather, then the decision whether to prefer one intolerable solution to another will be based solely on minimizing the badness of other lines in the given paragraph).—Emil J. 18:36, 29 September 2010 (UTC)

I see. Thanks for explaining that; I had wondered. --Trovatore (talk) 21:07, 29 September 2010 (UTC)

Unfortunately, I'm using normal LaTeX, with a long tradition of EPS figures. --Tardis (talk) 18:45, 27 September 2010 (UTC)

If you ever want to switch (I effectively did a small couple of years ago), ImageMagick supports convert Science.eps Science.pdf and mostly works well. --Stephan Schulz (talk) 07:40, 28 September 2010 (UTC)

Chances are that your TeX distribution comes with epstopdf.—Emil J. 12:09, 28 September 2010 (UTC)

Ah, I was being silly -- \sloppy was actually sufficient in this case, but I forgot to apply it to the \par in question. Thanks anyway for its internal details that might be useful later. Also thanks for \break; I had tried \newline and just \\, but they don't cause stretching. I wonder what the difference is between \linebreak and just \break? --Tardis (talk) 18:45, 27 September 2010 (UTC)

\newline and \\ basically do \hfil\break, so they will not right-justify the text, similarly to the end of paragraph. \linebreak is more or less a fancy LaTeX wrapper around \break (or actually around the \penalty primitive), the primary practical difference being that \break in vertical mode (i.e., outside paragraph) does a page break.—Emil J. 19:03, 27 September 2010 (UTC)

Safari Autofill data stealing

Does this:link removed currently work on Google Chrome? --Belchman (talk) 19:15, 27 September 2010 (UTC)

I imagine you are trying to indicate the Safari autofill exploit? (The proof of concept site demonstrating it that you linked to was apparently too much for Ludwig2, and maybe he is right. Anyway it is linked to from the blog I mentioned; proceed at your own risk.) It sounds like it only works with Safari. Googling "Chrome autofill exploit" seems to indicate that it does not suffer from this bug. --Mr.98 (talk) 19:36, 27 September 2010 (UTC)

It wasn't too much, but I thought it better to remove it until I'd had a chance to examine the code. do you disagree with that? --Ludwigs2 19:38, 27 September 2010 (UTC)

Are you done examining it? It took me about ten seconds to find out that it's harmless. It doesn't send the data anywhere.--Best Dog Ever (talk) 20:15, 27 September 2010 (UTC)

No. It doesn't. By the way, you can always test stuff like this in VMware Workstation or VirtualBox if it's too risky to try on your main system.--Best Dog Ever (talk) 20:11, 27 September 2010 (UTC)

Yes, I'm done. thanks for asking. --Ludwigs2 20:20, 27 September 2010 (UTC)

Thanks to everyone but Ludwigs2, of course. --Belchman (talk) 21:09, 27 September 2010 (UTC)

You need to apologize to Ludwigs2 for that, mate. Comet Tuttle (talk) 21:21, 27 September 2010 (UTC)

Er.. what? That was in no way a personal attack. At all. He/she doesn't have to apologize for not thanking a user who didn't help answer their question 82.44.55.25 (talk) 22:48, 27 September 2010 (UTC)

No apology needed, so long as he doesn't continue. I've warned him on his talk page. --Ludwigs2 21:27, 27 September 2010 (UTC)

Access 2007 and too many fields

I have somewhere around 116-ish fields in a table. I went into design view to change some of them from integer to decimal (about 50 of them). Now that I want to leave design view, Access claims I have too many fields and it won't let me save. What's wrong? 138.192.58.227 (talk) 23:02, 27 September 2010 (UTC)

Here are Access 2007's vital statistics. Maximum fields per table: 255. So the problem is somewhere else. --Tagishsimon (talk) 00:29, 28 September 2010 (UTC)

The only other options it has for what could be causing the problem is too many locks (I have no locks) or a setting about indexing that I have not used. 184.97.159.46 (talk) 01:25, 28 September 2010 (UTC)

Not a helpful answer, but: this sounds like exactly the kind of finicky and annoying buggy thing that Access is very prone to. It seems to get internally corrupted pretty easily in very subtle and strange ways. It may not have anything logical related to what you did. I know: this isn't helpful. But you may have to just close without saving, reopen it, and try again. I write this not as an anti-Access person, but as someone who has struggled with its deficiencies and inherent bugginess for over a decade. --Mr.98 (talk) 02:15, 28 September 2010 (UTC)

Thanks for the suggestion. I ended up having to split it into a few different tables, which fixed it. I'm just not sure how. 184.97.159.46 (talk) 02:36, 28 September 2010 (UTC)

That's pretty much how it goes with Access a lot of the time. I've been using it for ages, it's always been like this, from Access 97 through Access 2007. I don't expect it will change anytime soon... --Mr.98 (talk) 15:36, 28 September 2010 (UTC)

September 28

ISP big brother?

Does my internet service provider know all the sites I visit, dirty or otherwise? Can it follow what I am doing, peering over my shoulder seeing what Wikipedia articles I visit and which natural titty model I'm leering over? And if so, do they have any public policy on purging my browsing history, or, say, if I was running for U.S. Senator could a bit of well slipped cash allow someone to get dirt on me? I find the prospect that they can see what I'm doing kind of scary.--162.83.168.103 (talk) 03:37, 28 September 2010 (UTC)

It is technologically easy trivial for them to monitor all of your unencrypted communications. As long as your encrypted communications links are not tampered with (man in the middle attack), and are otherwise done properly, those are not viewable. There are laws, federal and state, that protect against blatant monitoring without consent, however you need to review the terms of your service to know what you've consented to. There are also exceptions in the law for monitoring used for some maintenance and of course court orders, but I know of no large ISP in the U.S. that openly monitors their user's ingress/egress data as a general rule. They do store some information for limited times, and websites you visit may store information as well, but again, as a general surveillance, I doubt any large ISPs do. Shadowjams (talk) 03:45, 28 September 2010 (UTC)

Note that even if your communication with the website is encrypted, they can still probably guess what sites you're visiting by your DNS lookups. One option would be run some sort of programme which randomly visits sites, I think those exist. If done properly, it may be hard for them to guess which sites you're actually visiting. Another is of course to ensure your lookups themselves are encrypted and use a DNS service you trust or alternatively use something like Tor (but if you do, bear in mind exit nodes have far less qualms abount monitoring what you do, and depending on how careless you are i.e. how much unencrypted traffic you do and whether you give away details which can identify you in said unencrypted traffic they may be able to work out who you are.) Nil Einne (talk) 03:57, 28 September 2010 (UTC)

Well that sucks! I guess it's pretty paranoid and maybe a bit daft to think anyone really cares what I am doing in particular being random internet guy, but still I don't like it. But I'm not very tech savvy. I wouldnlt kno where to begin with setting up a randomizer or a "tor" Also, I don't think a randomizer would fool anyone if they were actually looking because what they'd see is random, random, random, random, and then twenty related sites that are linked by topic because that's what I'm doing so they'd know that was really me.--162.83.168.103 (talk) 04:01, 28 September 2010 (UTC)

Your ISP publishes their privacy policy, which should contain all the details about what they do and don't monitor. Usually it's available on their website. My ISP sent me a copy with one of my bills. It said they do not log any websites I visit, but then there was a whole section on all the stuff they can do if they get a government subpoena. Read yours and plan your Internet-security measures appropriately.--el Aprel (^facta-_facienda) 04:28, 28 September 2010 (UTC)

You could also only visit sites you don't want to be tracked visiting via access points owned by others, such as the wireless network of a coffee shop, or McDonalds, or even some public libraries. You may find disagreeable content filters though. The Masked Booby (talk) 04:45, 28 September 2010 (UTC)

Anonymity is a hard technological problem. The tor project talks about this quite a bit, which may be of some interest to you. Bruce Schneier has a good blog post about the distinction between anonymity and privacy. The former is not at all private, but the identity is hard to link to you. The latter is secure, but who you're talking to is clear. Think about interactions with random strangers... you buy a cup of coffee in an airport. You're anonymous, but you're not private... it's clear to everyone around you bought a cup of coffee. The internet's a little bit like that. Shadowjams (talk) 06:07, 28 September 2010 (UTC)

Well I'm not going to do anything. I'm not important enough for anyone to really want to follow or log or bribe or expose through my ISP. It's just the principal I don't like. Thanks for the info.--162.83.168.103 (talk) 08:48, 28 September 2010 (UTC)

You could use a VPN or some other secure Tunneling protocol...but otherwise, yes, your ISP can "see" all the sites you go to...and depending on your ISP, this gets logged for up to a few years. There are plenty of other programs designed to monitor you including Perfect Citizen, Echelon, the Information Awareness Office, ADVISE, Carnivore (FBI)...not to mention more recent efforts.Smallman12q (talk) 00:14, 29 September 2010 (UTC)

submask

how doesa submask work????????please explain with an example...... —Preceding unsigned comment added by Naveenkumarrocks (talk • contribs) 12:16, 28 September 2010 (UTC)

I assume you are referring to a "subnet mask" by merging the two words into "submask". Subnet is short for subnetwork. It is a part of a network. In most cases, the network is all of the addressable internet. Using IPv4, every node on the internet is addressed with four numbers in the form 1.2.3.4. Each number can be up to 8 bits long (00000000 to 11111111, which is 0 to 255). There are reserved addresses, but that isn't important here. Due to the organization of the internet, addresses with sequential numbers are often on the same local network. All of the computers on a local network are considered a subnet. A subnet mask is a way of identifying which binary digits of the address are used to define the subnet. Lets assume that all of the first three numbers are requires. So, we need 1.2.3.* since every node on our local network has the address 1.2.3.something. The last number has 8 bits, but the first two never change for our local network. That means that the digits that never change for our local network are 11111111.111111111.11111111.11000000. The 1's never change. The 0's do change depending on which node you are addressing on our local network. That is the subnet mask. Converting binary to decimal you get 255.255.255.192. Now, by doing a simple masking operation on an address, I can see that 1.2.3.16 is on the same local network as 1.2.3.4. I can also see that 1.2.3.49 is not. -- kainaw™ 14:05, 28 September 2010 (UTC)

And the point of subnet masks is that networking devices (e.g. PCs) know that they can reach other PCs on the same subnetwork using (normally) Ethernet addressing. So they perform an ARP function to find the Ethernet (MAC) address and send the frame direct to that address, rather than sending it to their local gateway for forwarding to the wider world. --Phil Holmes (talk) 16:36, 28 September 2010 (UTC)

If your subnet mask is 255.255.255.192, then 1.2.3.49 is going to be on the same local network as 1.2.3.4 and 1.2.3.16. However, 1.2.3.149 (for example) is not. JIP | Talk 16:55, 28 September 2010 (UTC)

Correct. I was sure I had at least one major typo, but I didn't catch it on a read-through. -- kainaw™ 17:02, 28 September 2010 (UTC)

Article CIDR has more information on this. --antilived^{T | C | G} 03:35, 29 September 2010 (UTC)

More on facebook login

I asked a question a few days ago. Since then I've worked out that href="http://www.facebook.com/login.php?email=myname%40mydomain.com" gets halfway to doing a login. I tried adding &password=abcdefgh but that didn't fill in the password field. Anyone know how to achieve that? -- SGBailey (talk) 13:00, 28 September 2010 (UTC)

That can only answered by people who know about how that page is implemented; there's no way to see what parameters a particular page can take. My bet is that no such parameter exists because there's no secure way to use it. Publishing such a link would involve publishing the account's password. Using such a link without publishing it is probably unsafe, too, since the contents of URLs are not treated with as much care as form variables in POSTed forms, and for that, there's the "remember me" option and browser-saved passwords. I bet there are browser extensions for people who want to juggle multiple saved passwords. Paul (Stansifer) 13:49, 28 September 2010 (UTC)

If it has to be a HTTP POST, you could take this code and wrap it into a bookmarklet. --Sean 15:27, 28 September 2010 (UTC)

I'll try that. Thanks. -- SGBailey (talk) 21:53, 28 September 2010 (UTC)

DPI in Irfanview

I've been looking at some jpg images in Irfanview and pressing the 'I' key for information. I've noticed that they have different values for DPI, which I assume is dots per inch. After changing the DPI, the image does not appear to change in size. Why do images have different DPI, what is its significance? Does this mean that images with high values for DPI could be enlarged yet still have the same amount detail compared with low DPI images? Thanks

Supplementary question - how do I get images to open by default in Iranview rather than in the "Windows Picture And Fax Viewer"? I use WinXP. Thanks again. 92.28.249.130 (talk) 14:16, 28 September 2010 (UTC)

DPI is used primarily for printing (I can't think of any other use). It is printing size preference. Do you prefer the image to be printed at 30 DPI or 300 DPI? For print media, DPI is important. When sending images around in JPG format, DPI is used to quickly decide how large an image can be before it gets pixelized. If you aren't in print media, you can ignore it since it doesn't affect the image on the computer screen. As for the default application in XP, I remember it being: hold down shift and right-click on the file. You will see the new option "open with". Find the program in the open with dialog and check the "always open with this program" box when doing so. -- kainaw™ 14:42, 28 September 2010 (UTC)

DPI in the sense that you are seeing there is an internal value that relates only to a calculation of what you'd ideally want the output size of a given set of pixel dimensions to be. There are lots of attempts to explain it in more practical terms in the Reference Desk archives, other than the Dots per inch article we have. Explaining it can be a little tricky if you are not used to thinking about images for the purposes of printing quality (which you presumably are not, since you are asking about DPI in the first place).

The short story is that metadata DPI settings don't have anything to do with the pixel dimensions of the image. They have to do with how it is rendered on an output device. Monitors generally reproduce images at a 1:1 pixel ratio (which can vary in real-world DPI, but 72 and 96 dpi are usually the values you use in estimating), so changing the DPI setting won't change how it looks on screen. What matters in the end is the purpose of your output image. If you have a 300 pixel by 300 pixel image, and you print it out on something that requires 300 DPI to look "good", it will only print out "good" at 1" by 1". If you try to print it out at 2" by 2" it will be twice a poor (150 dpi). What you need to do to figure out how much "detail" an image would have when printed out, you first figure out how big you'd want the printout to be (e.g. 5 inches across), then figure out backwards what an ideal DPI would be for the device (300 dpi is pretty standard as a minimum threshold for things looking OK, so that would mean your image would need to be at least 1500 pixels across. Depending on your output device, you might want many more pixels than that). You can set the internal DPI of an image to any arbitrary amount, but it doesn't affect the total pixels. So our 300 pixel by 300 pixel image might have an internal DPI setting that says it is meant to be 150 dpi (and thus could be printed out at 2 inches by 2 inches), or it could have an internal DPI setting that says it is meant to be 3000 dpi (and thus could be printed out at a maximum length of .1 inches on each side). None of that would change the amount of pixels in the image, just how it is processed by a printer. The value of the DPI setting of a particular image does not, by itself, tell you anything about the amount of detail in the image; that's still always going to be in the pixel count. --Mr.98 (talk) 17:39, 28 September 2010 (UTC)

So in short, the DPI figure only affects the image when printed, and is not used when displayed on a computer screen? 92.24.188.89 (talk) 18:10, 28 September 2010 (UTC)

Basically... except it doesn't really affect anything. It's the number you get when you say, "I have this many pixels, and I want to print it out at this size." It's just an expression of that ratio. --Mr.98 (talk) 18:58, 28 September 2010 (UTC)

The DPI setting could be used for screen display. Modern versions of Windows, Linux and Mac OS are aware of the physical size of screen pixels and will report it to any application that asks. If your image says it's sampled at 300 DPI and your screen has 100 pixels per inch (a typical value), then scaling the image down by a factor of three horizontally and vertically will cause it to appear at the correct size. For the most part, image viewing software doesn't do this. I'm not sure why, but I think it just isn't seen as an especially desirable feature. Rescaling degrades the image quality, and most images don't have a "correct" size anyway. It's more useful to display them pixel for pixel, or scaled to fit on the screen with a minimum of wasted space. -- BenRG (talk) 20:10, 28 September 2010 (UTC)

mshome.net

What is mshome.net? The remote desktop program is connected to that site, but there doesn't seem to be anything there when I browse to it 82.44.55.25 (talk) 18:35, 28 September 2010 (UTC)

A whois lookup shows that Microsoft owns the domain, for what it's worth. You can grab it yourself if Microsoft forgets to renew it by the expiry date of May 8, 2012. Comet Tuttle (talk) 20:39, 28 September 2010 (UTC)

Word count in Publisher 2010

Hi there. Does anyone know how to get a word count in Microsoft Publisher 2010? Or if there's an add-on for this? the wub "?!" 19:31, 28 September 2010 (UTC)

See the following pages.

• Text analysis, wordcount, keyword density analyzer, prominence analysis
• Free Online Word Count Tool and Online Character Count Calculator

—Wavelength (talk) 19:39, 28 September 2010 (UTC)

Well yes, there's loads of word counters about (heck, I could roll my own in Python easily enough), but I'm really after something that can be used in-program. I should add that it's not for me but a customer, I wouldn't touch Publisher with a ten-foot pole. the wub "?!" 19:58, 28 September 2010 (UTC)

Googling around, it seems there is no built-in function. Apparently you have to do an Edit > Select All > Edit Story in Microsoft Word. Which is about the same as just copying and pasting it. Not very impressive, Microsoft... --Mr.98 (talk) 22:30, 28 September 2010 (UTC)

Matlab Array Column Misalignment - Help!

Hi there,

I recently asked the following matlab question - http://en.wikipedia.org/wiki/Wikipedia:Reference_desk/Archives/Computing/2010_August_22#Matlab_-_simple_column_vector_formatting_question - about formatting my column vectors in order to get them to display in a row of different length columns without trailing zeros. The solution given has worked in that sense, but unfortunately Matlab is making my output misaligned when it finishes, because the top row contains some 1 and some 2-digit numbers, whereas the second, third etc. rows contain only single digits - for example, I end up with something like

1   0   3   5   7   11   13   17   19   23   29   31   37   41   43   47   53   59   61   67   71   73   79   83   89   97
2   0   0   2   0   0   2   2   0   0   2   0   2   2   0   0   2   0   2   0   0   2   0   0   2   2
        1       1   1           1   1       1           1   1       1       1   1       1   1        

that, rather than having all 3-element columns aligned - the second and third rows are all correct, but because the top row has 2-digit numbers it goes wrong. Despite this, if I copy the string into any text-editor/web browser etc, or even into the Wiki editing box, it displays properly, in fixed columns - so it's clearly -storing- the string right, just not displaying it as I want. Is there any way to solve this problem at all? I've tried outputting the data as a matrix, adding column by column (with trailing zeros to make the vectors the right length), but this comes up with exactly the same problem.

Ordinarily I would just copy the output across to MS Word or something, but unfortunately this is for a project where we have to display the output of our programs by printscreening Matlab, so I have to get it displaying correctly in-program, if possible. Could anyone suggest anything? Perhaps it's not a matter of fixing the program but actually changing the Matlab settings themselves, but I have no idea after searching for a solution. Many thanks, Typeships17 (talk) 23:41, 28 September 2010 (UTC)

Disclaimer - I've never used Matlab. Having said that, if your maximum value is 99 can't you just zerofill your single digits to always be 01, 02, 03, etc? That way they'll line up in your viewer. Zerofill is a pretty basic function, and every programming language should have it. The Masked Booby (talk) 00:47, 29 September 2010 (UTC)

I too am not a Matlab user, but taking a quick look at the documentation, the fprintf function may serve your needs. For example, the statement fprintf('%5d', A); should (if I understand the documentation correctly) format all of the numbers in the array A as decimal integers right justified in a 5 character string. if A contains floating point values instead of integers, you might need to try fprintf('%5d', round(A)); to convert the matrix to integers. I hope this helps. -- Tom N (tcncv) talk/contrib 05:30, 29 September 2010 (UTC)

Follow up. Looking at the example referenced above, your solution may be to replace the num2str with sprintf. Try changing A = num2str(V); to A = sprintf('%5d', V); or A = sprintf('%5d', round(V));

September 29

Two hardware questions

Hello Refdeskers! I have two separate but related questions:

1. As you may be able to tell from my userpage, my computer is a piece of junk that can barely run more than one application at a time. So I've been planning a major motherboard upgrade to the following components: AMD Athlon II x3 440, 3.1 GHz, tri-core CPU; 2 GB of RAM; and the integrated ATI Radeon HD 4200 graphics chip all on an Asus M4A785-M motherboard. (Of course other components will be upgraded, but they are irrelevant to this question.) The power supply is rated at 250 W; I plan to keep that as is. My question is: does the Reference Desk, in its infinite wisdom, think this is enough power to watch and record HD video? I was told on another forum that a 2 GHz dual-core Pentium would probably be enough, but I would like to make absolutely sure before I buy anything (and this particular CPU is on sale!).
2. I recently appeared on a local TV show. This particular show is only broadcast on a local station in my area, but there are family in other parts of the U.S. that would like to see my appearance. I plan to record the show in Windows Media Center using an HDHomeRun, but then there is the problem of actually getting the recording to the relatives. Right now I plan to burn the show to DVDs and mail them out (obviously ignoring the potential copyright issues) but since that is a bit cumbersome and involves cost on my part, is there a better, preferably free way that someone in the same situation has tried before? The show is 30 minutes long and produced and broadcast in 1080i HD, so we're talking very large (~2 GB) file sizes here. Xenon54 (talk) 01:39, 29 September 2010 (UTC)

For (2), you can use Dropsend [1] or a similar service to send fairly large files (up to 2 GB, in Dropsend's case). This is only feasible if you and the recipient have reasonably speedy internet connections. Buddy431 (talk) 02:10, 29 September 2010 (UTC)

For (2), why not just ask the show's producers for several copies of that particular episode? I've been on a few local programs in my time and the staff was always happy to provide copies for myself and some relatives. That's a very common request. You may have to pay a small fee for their trouble, but to me that seems the easiest solution and you won't run afoul of any legal restrictions. Just give em a call and ask! The Masked Booby (talk) 03:21, 29 September 2010 (UTC)

Yes that is more than enough CPU power to watch and record HD video, although you should probably look at getting 4GB (2×2GB) of RAM instead. The power supply seems woefully inadequate - even my old computer bought in 2002 had a 300W PSU! 250W means it's either very old or proprietary for small form factor (or both) and I doubt you can even use it on modern hardware at all. Pick a modest (eg. 400W) PSU from a reputable brand, they aren't that expensive anyway.

As for (2), you can also host the files on your computer and get your relatives to download it directly from you (use a VPN like Hamachi if you want a little bit more privacy), but that'd require you leaving your computer on most of the time. If they don't have fast internet access you could perhaps use a flash drive as a medium instead of DVDs to reduce costs and transfer times, maybe establish a family sneakernet or something. --antilived^{T | C | G} 03:32, 29 September 2010 (UTC)

If it's a quality and real 250W ATX2.0 (i.e. decent 12V) PSU I suspect it could power a modern hardware. See for example what some 300W can power [2]. I'm not saying I recommend it Nil Einne (talk) 11:13, 29 September 2010 (UTC)

See also the second last post here [3] of a system running a picoPSU-160-XT which is a DC-DC converter which takes 12V and outputs the other necessary voltages (3.3V, 5V) and rated at 160W typical, 200W peak. You may also be interested in looking at real world (i.e. not theoretical) measured usage of various systems under maximum possible power usage load that people can achieve. Nil Einne (talk) 12:15, 29 September 2010 (UTC)

OK, so I found a 380W power supply for $20 from Newegg and I'll upgrade that. What would you say the lowest I can go is in terms of CPU? In order to save money I'm looking at a 3.0 GHz dual-core Athlon II instead of the tri-core. Would that be enough power? Xenon54 (talk) 22:13, 29 September 2010 (UTC)

I don't know what PSU you are looking at but that sounds rather cheap and looking at PSUs at that price on Newegg I didn't see anything that particularly inspires confidence. I did find [4] which should be a decent enough PSU. I'm not saying it's the cheapest decent PSU you can find, I didn't look that well and I'm not familiar enough with all I saw anyway (I come from NZ where there's less choice).

Cheap crap PSUs have a tendency to die much sooner then better quality ones. Far worse though is they can kill hardware when they die. Well I suspect all PSUs have a chance of doing so even if technically the ATX standards say they shouldn't, but cheap crap PSUs tend to do it a lot more then better ones. Since you're buying a relatively cheap system, this perhaps isn't quite as big a deal as those who buy super expensive systems then use crap PSUs but worth considering. Another important thing is cheap crap PSUs can also have problems giving a reliable supply leading to stability problems (whether from the beginning or as they die). Cheap crap PSUs also tend to be overated, so often you might as well get a decent but lower rated better PSU (380W isn't that high but I saw some 300W which would potentially be better then a cheap crap 380W).

You may also want to consider efficiency. You can get a 80 PLUS certified PSU (not the earlier linked one I think although its efficiency probably isn't to bad) for example the Antec Earthwatts 80 PLUS [5] or the Corsair 430CX [6] (not certified but the manufacturer says it's primarily because they have submitted it and it should meet the standards [7]). Note again I'm not saying these are the cheapest high efficiency PSUs they're just ones I came across (the Antec I looked for since it's one of the cheapest 80 PLUS PSUs here in NZ).

I'm not sure what the efficiency of the cheap crap PSUs are but it wouldn't surprise me if they are around 70% or even less at certain ranges especially the lower ranges e.g. 20-50% (where your computer is likely to be most of the time) which means more heat and more power used (i.e. more cost to you). [8] says 72% for one cheap PSU but doesn't specify at what output. The efficiency savings are unlikely to be enough to make up for the difference but the price may difference may not be as big as you think over time. For example if your power supply is 70% efficient at 100W it's drawing 142.86W vs one that is 82% efficient at 100W that's drawing 121.95W or 20.91W difference. If you take 8 hours per day of that, that means a saving of 167.25Wh a day or 61.087kWh a year. I don't know how much you pay for power but since you live in the US from [9] 11 cents/kWh is probably not unresonable so a savings of $6.72 per year on your power. 100W is probably a little high, I suspect your computer will be close to idle most of the time it's on but even so a few dollars savings per year is probably not unresonable.

In terms of the CPU and HD playback (which I think is primarily what interests you? Recording is largely irrelevant of course presuming your are referring to recording digital broadcast TV), you haven't specified what sort of HD content you are talking about. If you are talking about terrestrial HD broadcasts in the US, AFAIK most well probably all of these are MPEG2 which isn't really that demanding even in HD. In any case, but particular for H264 it's IMHO worth using the GPU instead of the CPU. The HD4200 does hardware decoding for H264, MPEG2 and VC-1 so it should be fine if set up properly and with the right codec. From memory, the HD4200 needs a hypertransport 3 (well greater then 1400mhz hyper transport I think) CPU for all the PureVideo goodies to work at their best although I think that's primarily an issue for stuff like quality deinterlacing rather then hardware decoding and AFAIK all Athlon II CPUs have HT3.

In any case, a decent dual core should also be fine even if you do use CPU decoding provided it's an efficient codec and although as I've said that wouldn't be my recommendation anyway. One instance where you may need CPU decoding is with likely copyright infringing downloads, as these may occasionally be encoded with settings the GPU doesn't support (although nowdays I think most are avoiding that especially given playback on game consoles where you have no option). Bear in mind certain programs like VLC on Windows don't support multithreading anyway so there's no advantage to a triple core over a dual core at the same speed in that sense or even a single core really (well some minor advantage due to background processes perhaps).

Nil Einne (talk) 07:35, 1 October 2010 (UTC)

Microsoft Windows update frequency

My PC is about 3 years old and runs Windows Vista. I like to know what is installed, so pretty much as soon as I got it I configured Windows update to download and let me know about updates (I know that's not Microsoft's recommendation, but I like it like that). When I first got the PC the updates came often, almost every day in fact. Recently I've noticed the updates have become much rarer (perhaps every 2 weeks) but there's usually several updates to be done at the same time. My PC is still reporting it is up to date, so has Microsoft changed the way in which Windows update works to reduce the frequency of updates? Astronaut (talk) 04:10, 29 September 2010 (UTC)

see Patch_Tuesday 194.39.218.10 (talk) 05:17, 29 September 2010 (UTC)

As the article says, Microsoft issues patches for Windows every second Tuesday of every month. However, some days there may be less updates that other days, so maybe that's whats happened to you. Chevymontecarlo - alt 06:45, 29 September 2010 (UTC)

No, I don't think it's that - Patch Tuesday was introduced in 2003. When I said recently I meant with the last few months. Indeed, if I look at the history of updates on my PC I can see for example in April 2008 I got updates on the following dates: 2, 3, 6, 10, 13, 15, 16, 18, 23, and 24. Updates continued in this fashion until March 2010 (which had updates on 2, 6, 10, 12, 14, 15, 25, and 31). Since then, updates have only been received twice a month so last month I got 1 update on 3 August and 17 updates on 13 August. Astronaut (talk) 09:57, 29 September 2010 (UTC)

I've noticed the same with my updates of Vista (which I do manually for connectivity reasons). I'd assumed that Microsoft were losing interest in Vista. Dbfirs 07:30, 30 September 2010 (UTC)

Remember, though, that there's much less to patch when it comes to Vista. Service Pack 1 was 434 MB! And then they had SP2, which was another 348 MB. Windows XP's SP2, in comparison, was 266 MB. I'd imagine there's not much left to patch.--Best Dog Ever (talk) 07:44, 30 September 2010 (UTC)

Agreed. When an operating system first comes out there are lots of things to fix, but it's been 4 years since Vista came out so I think it's not unreasonable to assume that the fact the patches are less often is literally because there are less things left to fix. Remember the updates don't (generally) add new features, they usually require you to upgrade to a newer version of Windows for that, the updates are just to fix problems with the existing software.  ZX81  ^talk 17:25, 30 September 2010 (UTC)

There might be something in this, but I would have expected a gradual tailing off of updates rather then a sudden reduction to a couple of days a month. Then again, the change in frequency reduction seems to have started 6 months after the retail release of Windows 7 in October 2009 - one could speculate 6 months might be a significant time step in Microsoft's update/support policy. Astronaut (talk) 07:05, 1 October 2010 (UTC)

Video WB correction

Hi,

I want to perform some white balance correction on some video footage and am wondering if anyone had any software recommendations?

Thanks! —Preceding unsigned comment added by 58.175.33.162 (talk) 07:54, 29 September 2010 (UTC)

I'm not sure, but you could probably try Adobe Premiere or a similar, lower-budget program. --Belchman (talk) 12:36, 30 September 2010 (UTC)

Can't access a certain website

Hello wikipedians, I see to have problems accessing one particular website - www.monash.edu.au and anything under that domain. It's a rather large university so i doubt it would be down constantly and http://downforeveryoneorjustme.com/www.monash.edu.au/ says it is up for everyone else. I'm at a loss to why this one particular website doesn't work, when i go on it or any other pages under that domain i get the "Unable to connect" page in firefox.

I've checked the hosts file and thats all fine. I'm an administrator on this computer, no viruses that im aware of (why would they target that site anyway), i checked my MTU was 1500.

I recently (~3 months ago) upgraded to ADSL2+ and got a new router, not sure if i had problems before then.

I checked the router settings and there doesn't seem to be any blocking on this website.

I tried a laptop connected to the same home network im on and it had the same problems, this is a fairly new laptop so i doubt it is my singular computer.

Any ideas? —Preceding unsigned comment added by 121.219.139.24 (talk) 08:51, 29 September 2010 (UTC)

Have you tried accessing it from a proxy? Sir Stupidity (talk) 09:05, 29 September 2010 (UTC)

Yes i have, i thought i put that in the post but i forgot to hit edit i guess ((using a proxy such as http://www.proxyforall.com/ makes the website work, i just checked. I'm not sure if this because it encrypts the URL names in some fashion or because it has a different IP or something totally different)) —Preceding unsigned comment added by 121.219.139.24 (talk) 09:11, 29 September 2010 (UTC)

Try flushing the DNS. Also try a traceroute to see if there's a problem somewhere between your computer and the host. Assuming you're on windows here's how or use this 82.44.55.25 (talk) 10:13, 29 September 2010 (UTC)

Try http://130.194.11.149. As with many webhosts, they use some sort of virtual server so this won't lead you to the main page but I think it should work even without any DNS. If that does work, then it may be some sort of DNS issue. While testing this, I also found Monash has an AAAA record for their website. If you have a misconfigured IPv6 setup then this could also be the cause as many browsers default to the AAAA. Try turning off IPv6 for the network adapter and see if this helps. Nil Einne (talk) 12:21, 29 September 2010 (UTC)

Yes, that worked more than it has been working, the IP address. I could actually see the title in firefox and the page but it was text only, no images. As far as im aware i dont use IPv6(Except with utorrent but thats tunneled through something i think). Flushing the DNS did nothing, thanks for the idea though. Here are the trace-route outputs Monash , google(as reference) wikipedia(reference)

Sorry but if uTorrent is using IPv6 then IPv6 is enabled. Whether it's using Teredo tunneling or whatever is somewhat irrelevant since uTorrent still I'm pretty sure relies on the IPv6 stack of your OS. While I don't think it's a problem in this case from the traceroutes, it's likely worth disabling it for the network adapter when troubleshooting.

Anyway from the traceroutes, the problem may be because your trying to connect to the server 32.1.3.136. This is odd since from a lookup both locally and via a public web nslookup services it appears that the correct address is 130.194.11.149. It's possible I think that there may be some reason for this, e.g. they use a different server or some sort of cache for your ISP but I wonder if it's a problem with your ISP. I find some discussion of 32.1.3.136 primarily related to Ubuntu servers in Australia perhaps with Telstra. I also see some suggestion that disabling IPv6 may help in a few cases although this appears to be with Ubuntu, but you may want to try it just in case (I don't really see why it's relevant here since you seem to be getting an A record).

I would suggest you try setting your network adapter (or router) to use some other DNS server like Google Public DNS. Once you've done so make sure you flush your DNS cache etc as suggested above. If the problem goes away, and then returns when you use your ISPs DNS server again, it seems likely there's a problem with your ISPs DNS servers (they're giving you a IP for the server which either isn't the proper one or isn't working). Therefore in that case and if the problem remains after a few days, I would contact your ISP and tell them. Even if the problem isn't technically their fault but is caused by the Monash or some other NS server providing their NS server strange records, it's likely easier for them to work out what's wrong. (If your up to it, you could try querying Monash's NS server yourself and if it works, see what A record they give you for www.monash.edu.au.)

If the problem doesn't go away when you use a different DNS server, are you sure you haven't set a funny IP for Monash in your hosts file?

Nil Einne (talk) 22:52, 30 September 2010 (UTC)

World daylight map - free screensaver?

Where could I find a free screensaver that shows which part of the world is in daylight, like this image http://wwlln.net/TOGA_network_global_maps.htm Thanks 92.15.9.254 (talk) 13:12, 29 September 2010 (UTC)

This is not necessarily a screensaver, but possibly a preferable set of images: http://www.fourmilab.ch/earthview/.

—Wavelength (talk) 14:41, 29 September 2010 (UTC)

Something like EarthView or else play with this google search. --Tagishsimon (talk) 18:10, 29 September 2010 (UTC)

I've followed this tutorial to get daylight background map with clouds on my FreeBSD GNOME desktop with Xplanet. --Dereckson (talk) 23:51, 29 September 2010 (UTC)

hard drive

Is this hard drive about to fail [IMG]http://imgur.com/wZy7X.gif[/IMG] —Preceding unsigned comment added by 174.139.74.140 (talk) 14:45, 29 September 2010 (UTC)

That is a symptom, but not necessarily a guarantee, of "imminent" hard-disk failure. See our article's list of S.M.A.R.T. attributes for some context. The long answer is that statistical analysis of hard-disk failures indicates that these SMART attributes are weak indicators of potential failure - many times, their data is not a very good predictor of failure. Nimur (talk) 21:02, 29 September 2010 (UTC)

The indicators tell you if something is abnormal, but with the robustness in modern hard drives the question becomes "will that little problem ever become a big problem?" and the answer may be no. I have had several hard drives fail while giving off SMART warnings, and in all cases I was able to recover the data gracefully and have them returned for warranty. Ignoring the SMART errors probably would have put the data in jeopardy if I simply waited until the drives completely failed. If the disk is under warranty by all means get it replaced when *any* SMART error comes up, that's why drive makers offer such long warranty periods (3 to 5 years is typical.) With all that being said, I have had a drive give off the exact SMART error you are seeing; I took it out of primary service and use it as a temporary bulk storage drive and have not had it deteriorate in about 2 years of use. It does exhibit occasional 'hiccups' due to the spin problem whereby it will not transfer data for a few seconds, but it doesn't lose or corrupt data. So, ask yourself what your definition of "fail" is... --144.191.148.3 (talk) 15:34, 30 September 2010 (UTC)

IMHO, if the data on the HDD is valuable to you, either replace the HDD or make regular data backups. If the HDD is still under warranty, exchange the failing harddisk for a new one. Waiting until the harddisk actually fails can cost you money or the loss of valuable data. Rocketshiporion♫ 03:11, 3 October 2010 (UTC)

I think both of you guys are over-exaggerating. How old is this drive? I have five HDDs in my PC -- some of them a few months old -- and HD Tune Pro gives the spin-retry count on each one as "100." I saw another screen shot in the manual of a drive with a retry count of 249. Also, you don't have any re-allocated sectors. I've seen screen shots with a high number of re-allocated sectors. But, then again, there is nothing in the data column for any of my drives. Nor does it say "warning." Instead, it says, "ok" for the status. Do you get any more info when you click on "Log"? It should tell you in plain English that you have a damaged HDD if that's the case. Nevertheless, I would recommend backing up your hard drive. In fact, I recommend that everyone backs up up their hard drive. You don't have to replace it, though.--Best Dog Ever (talk) 22:39, 3 October 2010 (UTC)

Ping Localhost

When I try and ping localhost I get this:

Pinging Unknown-PC [127.0.0.1] with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 127.0.0.1:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

The internet is working fine. I started Apache and browsing to localhost in Firefox works fine too. What is going on here? 82.44.55.25 (talk) 15:32, 29 September 2010 (UTC)

All that means is your computer isn't responding to ping. No big deal. -- kainaw™ 15:43, 29 September 2010 (UTC)

I know the computer isn't responding to ping; I want to know why, and how to fix it. 82.44.55.25 (talk) 15:53, 29 September 2010 (UTC)

What is your operating system? Do you have a firewall running? Do you have SELinux running? -- kainaw™ 15:58, 29 September 2010 (UTC)

The computer is Windows 7. The standard Windows firewall is running, and I haven't changed any settings there recently. I tried disabling the firewall but ping still doesn't work. I don't know what SELinux is, but I'm pretty sure I don't have it. 82.44.55.25 (talk) 16:01, 29 September 2010 (UTC)

In Windows 7 it is almost always the firewall. See here. -- kainaw™ 17:01, 29 September 2010 (UTC)

I tried disabling the firewall but ping still doesn't work. I added a new "Inbound Rule" as the guide you linked to suggested, but again ping still doesn't work. I can ping everything BUT localhost - pinging google.com works as normal for example. 82.44.55.25 (talk) 17:19, 29 September 2010 (UTC)

Why do you want to ping 127.0.0.1, anyway? It's pretty pointless. You already know that the machine is up.—Emil J. 10:26, 30 September 2010 (UTC)

Pinging localhost should work. The fact that it doesn't indicates a problem with the computer. I want to resolve it in case it leads to something else which does effect the computer in a more serious way. 82.44.55.25 (talk) 10:46, 30 September 2010 (UTC)

Microsoft considers responding to a ping to be a security flaw. So, it is disabled. It should NOT work on Windows 7. If it does, you have done something to the computer that Microsoft considers to be weakening the computer. -- kainaw™ 12:08, 30 September 2010 (UTC)

Is this right? We ping Windows 2003 servers all the time to see if they are up. Has the default changed? If so its something we will have to take into account when we upgrade (and change from the default setting or find some other way of testing for a server's presence). -- Q Chris (talk) 13:16, 30 September 2010 (UTC)

Ok, so how do I enable it then? From the first time I installed Windows 7 2 years ago I've been able to ping localhost without altering any settings whatsoever. This problem has only started in the last few days. 82.44.55.25 (talk) 13:28, 30 September 2010 (UTC)

The server is being delivered with a bit different default settings than Win7 for home users. It is assumed that home users will be inherently unsafe with their computers. So, ping is disabled in many areas of the computer. The firewall blocks it by default. Many other services block it, such as the AGN filter interface. Further, if you stop the firewall, it disables the network interface by default (that took a long time to figure out). You have to keep the firewall running, but set it to disabled. We simply don't try to ping Win7 on desktop machines. It isn't worth the trouble to get them to respond. -- kainaw™ 13:28, 30 September 2010 (UTC)

I don't understand. If ping is disabled by default, then how can I still ping everything except localhost? I can ping google.com, en.wikipedia.org etc and they all respond as normal. I've completely disabled the firewall (here is a picture) and it's still not working so it can't be the firewall causing this. 82.44.55.25 (talk) 13:42, 30 September 2010 (UTC)

google.com, en.wikipedia.org etc have not disabled ping on their servers. This has nothing to do with settings on your computer.—Emil J. 13:51, 30 September 2010 (UTC)

I haven't disabled ping on my computer either. It was working until yesterday 82.44.55.25 (talk) 14:04, 30 September 2010 (UTC)

(outdent) Don't confuse a ping host with a ping server. When you run the ping program to check on another computer, you are running the ping host. The other computer has a ping server that responds. When you ping localhost, you are having the ping host on your computer try to talk to the ping server on your computer. In Win7 set up for homes, Microsoft has gone to great lengths to stop the ping server from responding. They block it with the firewall. They block it with network filters. They renamed it to "echo server" so people won't find it. They don't have it running by default, so you have to go into network services and start the echo server. Even after all of that, every update seems to find another way to stop the server from responding. -- kainaw™ 13:50, 30 September 2010 (UTC)

Can you help me enable it again then? I don't know what has turned it off, I have windows update disabled and I haven't changed or run any new programs in the last few days. Disabling the firewall hasn't worked, and adding the rule exception you linked to earlier didn't work either. What are network filters? How do I start the echo server? 82.44.55.25 (talk) 13:53, 30 September 2010 (UTC)

Kainaw I think you are wrong. Surely Windows 7 would enable a user to ping their own computers loopback device, even if it blocked all incoming ping requests from external sources. Indeed, Microsoft themselves recommend pinging localhost as a way to test TCP/IP connectivity. 109.193.227.56 (talk) 14:57, 30 September 2010 (UTC)

Two things.

1) That article is for Windows XP. If you visit it with Windows 7 or Windows Vista or some other OS you will get "This article applies to a different version of Windows than the one you are using. Content in this article may not be relevant to you.Visit the Windows...". Microsoft can of course change their minds about how to do stuff.

2) While I don't know if Kainaw is correct, it sounds like Kainaw is saying Microsoft is wanting to make it difficult to enable responding to echo requests, by doing various things including disabling the actual server. This isn't possible if you want to be selective. Microsoft may also be concerned about possible bugs in their implementation of localhost only so prefer not to try (in particular, by disabling the server by default, it's one less server which could have bugs and which could be exploited). Microsoft may also be concerned that by enabling it for local host, people may get confused (I can ping myself, why can't others ping me). In other words, there are several reasons why Microsoft would want to disable it for everyone including local host.

Nil Einne (talk) 21:52, 30 September 2010 (UTC)

So how do I enable pinging localhost again? And what has caused pinging localhost to be disabled after 2 years of working? 82.44.55.25 (talk) 22:01, 30 September 2010 (UTC)

Why? Possibly a program accessing the the internet decided that it could not allow you to ping your computer. Or an Windows update has also in the process stopped you to ping it. Sir Stupidity (talk) 07:56, 1 October 2010 (UTC)

I don't run any Windows updates, and I haven't run any new programs recently. How do I enable pinging localhost again? 82.44.55.25 (talk) 10:02, 1 October 2010 (UTC)

Perhaps you should re ask the question again as everyone thinks this issue has been resolved. Sir Stupidity (talk) 07:42, 3 October 2010 (UTC)

I don't know if we think this issue has been resolved. I didn't but I wasn't sure how to help. Nil Einne (talk) 06:16, 4 October 2010 (UTC)

My laptop runs Windows 7 and it responds to pings directed at 127.0.0.1. The Windows firewall is turned on, too. Usually, when I can't ping 127.0.0.1, the computer won't connect to the Internet. In such a case, I usually re-install TCP/IP. (See this article for more information.) However, as the OP said, his connection is working. So, if it isn't broke, I wouldn't try to fix it. They could break something else while trying to fix the ping issue.--Best Dog Ever (talk) 07:23, 4 October 2010 (UTC)

free touchscreen software like a whiteboard to save handwritten documents

hey, i wanted to use my laptop like a notebook in uni lectures, but it doesn't seem t ohave software already instlled to do that. in school we used to have interactive whiteboards at the front of the class and the teacher would digitally write on that and be able to save each virtual sheet. and many sheets could be open at one time, and the each sheet could be scrolled down to the bottom and extended. the software they had is exactly what i want, but i think it came with the interactive whiteboards and i want somthing that's free... or i don't mind downloading illegally if it's easy to find to download. thanks for any help! 192.150.181.62 (talk) 18:40, 29 September 2010 (UTC)

What kind of laptop do you have? Is it a tablet? Looie496 (talk) 18:48, 29 September 2010 (UTC)

Yeah, a HP TouchSmart tm2 which is a tablet - it's like a normal laptop but the screen turns and folds to make it a tablet. 192.150.181.62 (talk) 19:32, 29 September 2010 (UTC)

To make sure we're all on the same page: you know, I take it, that your computer came with a digital pen and an application that allows you to write handwritten notes and save them. (I haven't used one, but this is my understanding.) What you want is a better note-taking application. Is that correct? Looie496 (talk) 00:30, 30 September 2010 (UTC)

I might be missing the point here, but what's wrong with a notepad and pen? Both are considerably cheaper and lighter than a tablet PC, require no electricity, are resistant to rough handling, and very flexible for notetaking in university lectures. Astronaut (talk) 11:27, 30 September 2010 (UTC)

"Windows:Tablet Edition" is supposed to come with "Windows Journal" which does exactly what you describe. It's quite handy.

http://www.microsoft.com/windowsxp/using/tabletpc/russel_03january20.mspx APL (talk) 16:05, 30 September 2010 (UTC)

I couldn't find any application on my laptop to do this. Windows Journal is EXACTLY what I wanted, thank you, it's not in the list of all programs in Start Menu oddly, but I searched it and it came up. Thank you so much. THe problem with a notepad an pen is that I lose all my notes, and they're ont organised or anything,cwhereas this does it all, and the notes can be duplicated and transmitted in seconds. Thanks again! 192.150.181.62 (talk) 20:48, 30 September 2010 (UTC)

computer

what is the name of the first computer used? —Preceding unsigned comment added by 199.93.81.1 (talk) 22:57, 29 September 2010 (UTC)

Not the easiest question to answer, for it depends on your definition of computer. History of computing explains the difficulties, and would probably answer "a piece of string with 12 knots". History of computing hardware takes you through the various epochs of hardware development. But I suspect something like the table in ENIAC is probably what you're after. --Tagishsimon (talk) 23:18, 29 September 2010 (UTC)

"The first working von Neumann machine was the Manchester "Baby" or Small-Scale Experimental Machine, developed by Frederic C. Williams and Tom Kilburn at the University of Manchester in 1948" according to the article linked above. 92.29.120.195 (talk) 19:45, 30 September 2010 (UTC)

On a related note, what was the hostname of the first computer where that parameter would have been relevant? I'm guessing it would have been an early private network, and I'd bet that the hostnames were "terminal" and "computer," respectively... but can't find this in our history of the internet or related articles. Nimur (talk) 09:52, 30 September 2010 (UTC)

Networking and server-host systems existed before ARPANet/Internet. So, it would precede the history of the Internet. If you are specifically looking for Internet usage, I'd check with Iowa State University because I figure they had one of the first computers on the network. -- kainaw™ 13:32, 30 September 2010 (UTC)

Used how? The first modern computer (to be publicly known) is considered to be the Z3 completed in 1941.Smallman12q (talk) 22:14, 1 October 2010 (UTC)

What regulatory issues have to be considered when exporting or building products that heavily use cryptography?

What federal laws do you have to be aware of when implementing software that incorporates cryptographic protocols? This question is for the US as well as internationally. Procrastinatus (talk) 23:48, 29 September 2010 (UTC)

Our article section Cryptography#Legal issues and our article Export of cryptography in the United States have some information that will be useful. Unfortunately our general article Export of cryptography is a stub. Comet Tuttle (talk) 23:54, 29 September 2010 (UTC)

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

---

None if you do it anonymously. ¦ Reisio (talk) 04:58, 30 September 2010 (UTC)

This is false. Just because you don't put your name on something doesn't mean it can't be traced back to you, and certainly doesn't mean you can ignore legal requirements. "Do it illegally" is both bad legal advice, and bad advice anyway. --Mr.98 (talk) 13:00, 30 September 2010 (UTC)

If it can be traced back to you, you didn't do it anonymously. Doing things in accordance with laws (that apply to you or do not) won't keep you out of trouble, either. The only way to be sure is to be anonymous. Also, I'll thank you to leave my comments alone. ¦ Reisio (talk) 04:37, 1 October 2010 (UTC)

We strike on the Reference Desk when really bad advice is being given. This is not article space and it is not talk space. Anyway, "do it illegally, but don't get caught" is both legal advice and bad advice. If you disagree with my striking it out, please feel free to complain on the talk page, but I think you'll find you're in the minority on this one.--Mr.98 (talk) 02:14, 3 October 2010 (UTC)

Not that you seem to care at all, but see second paragraph. ¦ Reisio (talk) 18:45, 3 October 2010 (UTC)

Note that the Reference desk is not supposed to give legal advice.—Emil J. 10:23, 30 September 2010 (UTC)

So far I have only seen one instance of "legal advice" above (which I removed; it was not informed, anyway, just suggesting that they "do it anonymously" and could therefore ignore the law, so there is no loss) — the rest is just pointing in a general direction towards resources for further information, which is completely valid. --Mr.98 (talk) 11:29, 30 September 2010 (UTC)

I would get in touch with the Electronic Freedom Foundationif you want a really comprehensive and probably accurate answer that has real legal analysis behind it. --Mr.98 (talk) 11:29, 30 September 2010 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

September 30

Hack firefox to reenable saving passwords

My Firefox has password saving disabled; how can I reenable it? Do I edit something in about:config? The Hero of This Nation (talk) 12:54, 30 September 2010 (UTC)

• On Windows, I think you just need to check the box at Tools -> Options -> Security -> Remember passwords for sites. --59.95.97.116 (talk) 14:20, 30 September 2010 (UTC)

• Sorry for not being more clear in my initial question, but that option is disabled in my Firefox options. Meaning greyed out, can't click it. I am in Firefox 3.6.6 for Windows. The Hero of This Nation (talk) 15:46, 30 September 2010 (UTC)

I don't know why it has been disabled, but perhaps going to about:config and setting signon.rememberSignons to true will do the trick? --Sean 16:48, 30 September 2010 (UTC)

Protocol for electrical signals going from computer to monitor.

What is the protocol for the graphical information about what to put on the screen at the very lowest level where the electrical signals are going through the wire to the monitor? This must be a standard since I can connect a different manufacturer's monitor to my computer and still have it work. Thanks. 20.137.18.50 (talk) 13:39, 30 September 2010 (UTC)

Much of this is specified, or at least standardised, by VESA; see the articles linked from there, and from Computer display standard. See also the VGA connector article. -- Finlay McWalter ☻ Talk 13:48, 30 September 2010 (UTC)

Eskimo Question

what is the differnces between the eskimo and aboriginal people and why? i need every detail please and thank you —Preceding unsigned comment added by 68.179.16.89 (talk) 14:53, 30 September 2010 (UTC)

"Aboriginal" is a general word that can refer to any indigenous people. (Australian Aboriginals, Native Americans, Eskimos, etc.)

"Eskimo" is more specific. It refers mostly just to Yupik and Inuit people.

(Incidentally, if you know which group of people you're talking about, nowadays it's often considered more polite to say "Yupik" or "Inuit".) APL (talk) 15:57, 30 September 2010 (UTC)

I think this should be in the Humanities reference desk. And the difference is that they live in different areas of the worldSir Stupidity (talk) 07:51, 1 October 2010 (UTC)

http status codes

I need a program for Windows that can monitor many urls http status code ever 10 mins or so. Similar to this site http://www.404checker.com/404-checker but offline version —Preceding unsigned comment added by 174.139.74.140 (talk) 18:07, 30 September 2010 (UTC)

This is probably something cURL could do, if you put it in a shell script.--el Aprel (^facta-_facienda) 20:08, 30 September 2010 (UTC)

I would strongly suggest that you learn a programming language for this kind of thing (one of the widely used "scripting languages"—Python is probably a good choice). Then you can (for example) do a Google search for "python http", which turns up this page, at the bottom of which is this example:

     >>> import httplib
     >>> conn = httplib.HTTPConnection("www.python.org")
     >>> conn.request("HEAD","/index.html")
     >>> res = conn.getresponse()
     >>> print res.status, res.reason
     200 OK

Once you know the basics of Python programming, you can easily turn this into a script that will loop over many pages, repeat every ten minutes and do whatever you want with the status codes. The entire process will probably take less time than you would need to read the documentation for curl's many command-line options. The up-front cost of learning Python will repay itself unless you never expect to need to do a task like this again. -- BenRG (talk) 21:05, 30 September 2010 (UTC)

Well said, BenRG. The exact purpose of a high-level scripting language, like Python, is to allow a power user to define a complex custom task, like "repeat this operation every 2 minutes." The OP should not be intimidated by the learning curve - scripting is easy and straightforward (and does not require as much sophisticated formal training as general purpose computer programming). Besides, as BenRG has pointed out, any specialized program that could provide the level of customizability that the OP has requested would essentially be a scripting language; so it would really serve the OP best to choose a general purpose tool so the learned skills are re-usable. Python has the advantages of being platform-portable, generally "easy to read", and has an enormous user base, so it is easy to find information on the web or ask for help. Other good languages to know are perl, bash scripting, and PHP; all are capable of accomplishing the same tasks, but each has unique capabilities targeted at solving particular styles of problems. Nimur (talk) 22:49, 30 September 2010 (UTC)

MS Zone.com online games in WinXP

Zone.com is part of Microsoft. I often play these games using the Programs/Games/ menu in WinXP. No logging on or user name is required, an anonymous nameless opponent is rapidly found and you play.

How do these games link up with others? What is the protocol used? I often play these games, including just a few seconds ago, so the information from Microsoft saying that they were retired in 2006 cannot be true, or must refer to something else. Nor am I using as far as I know a Live Messenger version of the games, as I do not need any user name etc. Thanks 92.29.120.195 (talk) 20:16, 30 September 2010 (UTC)

Some are Flash, some are Java applets, some appear to be Active X. Each of these can open their own connections back to the server from which they came; to minimise problems with firewalls etc. they probably do that over HTTP. -- Finlay McWalter ☻ Talk 21:53, 30 September 2010 (UTC)

These games probably use the Internet Games Core component.Smallman12q (talk) 01:04, 1 October 2010 (UTC)

This http://forums.techarena.in/windows-xp-games/752409.htm seems to relate to what I use, I think. I do not understand it. I ask because in recent weeks when I try to have a game there has often been no responce from the server, according to an error message. I've been wondering if the protocol is something to do with Windows Messenger. The current version of Windows Messenger is fourteen, but my installed version is only version four. I do not like Messenger and do not want any more annoying spam pop-ups, but if I updated Messenger would it reduce the proportion of times I get no responce from the server? 92.28.254.154 (talk) 21:27, 2 October 2010 (UTC)

Who physically made the first Apple Computers

I mean who physically made them once the number of orders exceeded what Steve Wozniak could do by hand? 76.27.175.80 (talk) 21:10, 30 September 2010 (UTC)

I suppose you're looking for the manufacturer of the Apple II, But the original Apple I kits were assembled by Steve Jobs, Steve Wozniak, and Ronald Wayne. (I'm pretty sure Wozniak was doing the difficult technical work. ) They only sold about about two hundred of them in over a year, so it wouldn't surprise me if they didn't need outside help.APL (talk) 21:55, 30 September 2010 (UTC)

Please see our Apple I article for more info. There are a few references there on this issue. Hope it helps. - 220.101 talk^\Contribs 04:24, 1 October 2010 (UTC)

From woz.org/letters/general/13.html, "WOZ:First, the Apple I (and Apple ][) computers were entirely designed and tested and debugged in my Cupertino apartment (not the garage) and in my cubicle at Hewlett Packard in Cupertino (that 'calculator' division is now in Corvallis, Oregon). The PC boards of the Apple I were made in Santa Clara. As soon as they came off the production line (only 200 total were manufactured) components and chip sockets were inserted by workers and the board were wave soldered there. This was the major manufacturing step. We'd drive down and pick up a batch of boards and then drive them to the garage. We'd pay Patti Jobs and other friends $1 per board to insert all the chips from boxes of chips that we had. The garage had a single engineering workbench with a mylar top and a shelf. A monitor and transformers and keyboard, the other 3 pieces of an Apple I, were on it, as well as an oscilloscope of mine and maybe a soldering iron. I'd hook up a PC board and try it out. If it seemed to work, it would go in the 'good' stack. If it was bad I'd look at the microprocessor data and address pins with the oscilloscope. If I saw a missing signal it meant that a chip had a pin out of a socket. If a signal seemed like two fighting signals (halfway between high and low) it meant that two traces were shorted on the PC board. About half of the boards had such problems. " So it was another company who physically made the boards and soldered the sockets in, then Jobs's sister Patti and some others did the remaining physical work. 20.137.18.50 (talk) 13:50, 1 October 2010 (UTC)

October 1

Long delay after first right click

The first time I right click something after initial booting up, the big hour glass comes up and it takes a looooong time for the menu to drop down--as much as 3 minutes. After that first right click everything is back to normal; the menu drops down immediately. What causes this delay?

I use XP.

Thanks,

Norm Strong —Preceding unsigned comment added by 71.231.141.223 (talk) 04:03, 1 October 2010 (UTC)

If it's the first right-click on the desktop or a file-explorer window, then I'd suspect a Shell Extension is being loaded. These are programs that add items to the context (right-click) menu of explorer. Explorer also provides the desktop (and the taskbar). However, I'm not sure about that best way to temporarily disabling an program from the menu, to help track down what is causing it. Have you installed a program recently? —Preceding unsigned comment added by Csmiller (talk • contribs) 06:05, 1 October 2010 (UTC)

I would be cautious; it could be malware infecting a shell extension, and was probably installed recently. Run virus scans, check for malware with a malwate scanner like Malwarebytes' Anti-Malware and maybe run Autoruns to check what is loaded at startup. Astronaut (talk) 07:22, 1 October 2010 (UTC)

I have seen this happen due to bad drive mappings causing all sorts of incredible slowness including when using the rightclick menu anywhere in the system. If you have any drives mapped try removing them and see if it speeds up. The other big culprit I have had do this is WinZip (or similar file archive tools) that use shell extensions for all files; if the program is misbehaving (not uncommon for WinZip) it can cause slowness. I once had it fail so bad that every right click caused the WinZip installer to try to start up, which took a fair bit of time and eventually exited with an error message. I had to manually delete all the references from the hard drive and registry before it would go away. Now, I use 7-zip and while slower to do file operations the shell integration works without issue. --144.191.148.3 (talk) 14:41, 1 October 2010 (UTC)

Spanish Accents

Right, this is going to be a tester. To get Spanish accents I usually hold down Ctrl and Alt at the the time, and while holding them I press the vowel of my choice. That results in á, é, í, ó and ú. I get ñ by holding down Alt and typing 0241 on the number pad. That's all well and good when I'm using a QWERTY keyboard and Windows. I'm in France at the moment and am using an AZERTY keyboard and Ubuntu. The Ctrl + Alt method doesn't work and nor does Ctrl + 0241. Does any one have any idea - except for cutting and pasting - how to get these accents? — Fly by Night (talk) 08:01, 1 October 2010 (UTC)

See our Compose key page. Basically, press Shift+AltGr (press AltGr last, release first), release both keys, press and release ', press and release the vowel. CS Miller (talk) 08:06, 1 October 2010 (UTC)

I've just tried that and I got 'e as the output. I did the following:

• Press and hold Shift
• Press and hold Alt Gr
• Release Alt Gr
• Release Shift
• Press '
• Press e

Are you sure it works on Ubuntu? — Fly by Night (talk) 08:18, 1 October 2010 (UTC)

Odd. It works for QWERTY keyboards on Ubuntu, but not on AZERTY. Apologies. CS Miller (talk) 08:37, 1 October 2010 (UTC)

Add a keyboard layout (System --> Preferences --> Keyboard --> Layouts --> Add). Then click on Layout Options --> Layout switching to create a keyboard shortcut for changing layouts. This is also the better way to type Spanish words in Windows, by the way. In Windows, I created keyboard shortcuts for switching to Spanish, Greek, and Russian keyboards by going to Start --> Control Panel --> Regional and Language Options --> Languages -> Details... --> Add.... The semicolon key types an N with a tilde. The left-bracket key adds an accute accent to any vowel you type afterward.--Best Dog Ever (talk) 08:32, 1 October 2010 (UTC)

Great, thanks for that! — Fly by Night (talk) 09:13, 1 October 2010 (UTC)

I always use charmap instead of key combinations. Comet Tuttle (talk) 16:29, 1 October 2010 (UTC)

But Ubuntu is a Linux based operating system and doesn't have anything to do with MS Windows. — Fly by Night (talk) 19:59, 1 October 2010 (UTC)

in Ubuntu, hold alt gr, then press #. Release both keys then press a. Do you get à? For me, ñ is alt gr and ], then n, and I can get most accented characters simlarly. 129.67.37.143 (talk) 22:36, 1 October 2010 (UTC)

Recursively Search a Directory to Find and Replace Contents of Files Using the Command Line

I'm trying to write a small shell script on OS X that will recursively search through a directory and replace all the instances of 'foo' in files with 'bar'. I assume that grep and sed are the best way to do this, but I can't quite figure out the syntax to make them work together.

Thanks for any help. --CGPGrey (talk) 08:20, 1 October 2010 (UTC)

grep -rl foo . | xargs sed -i backup s/foo/bar/

This will also create backups of the files it modifies (the original filename, plus a .backup extension) —Obeattie (talk) 12:42, 1 October 2010 (UTC)

Thanks for that, unfortunately, I'm on OS X, which does not allow the use of the -i switch. Is there another way? --CGPGrey (talk) 13:10, 1 October 2010 (UTC)

I too am on OS X, which seems to allow -i, I just tried it. What OS version are you using? —Obeattie (talk) 13:16, 1 October 2010 (UTC)

Perhaps you have installed the GNU utilities? This page says GNU sed supports -i but that the BSD one that ships with OS-X does not. -- Finlay McWalter ☻ Talk 13:27, 1 October 2010 (UTC)

Anyway, this isn't quite so nice, but it can be done faily easily just using a for loop. This removes the dependency on the -i flag:

for f in $(grep -rl foo .); do mv $f $f.backup; sed s/foo/bar/ $f.backup >| $f; done

—Obeattie (talk) 13:24, 1 October 2010 (UTC)

This looks to be getting me the closest, but I'm getting a ton of 'no such file or directory' errors when I run it and it produces lots of empty files in the directory that I run it from. Perhaps it's because I have spaces in the names of my folders and files? --CGPGrey (talk) 15:05, 1 October 2010 (UTC)

Yes, that's the reason. I would respectfully suggest that if you are planning to perform more scripting jobs like this, you rethink the naming conventions of your files so that they do not involve spaces. As you can see, it is nothing but a constant source of headaches. You can try

grep -rl foo . | while read f; do mv "$f" "$f.backup"; sed s/foo/bar/ "$f.backup" > "$f"; done

(inspired by Tardis' answer to your previous question).—Emil J. 16:08, 1 October 2010 (UTC)

Actually, there is one more subtle problem: all the sed commands above will fail to work properly if there are more occurrences of foo on the same line. You should use sed s/foo/bar/g.—Emil J. 16:25, 1 October 2010 (UTC)

(e/c) This suggests an explicit -e might fix it: sed -i backup -e s/foo/bar.—Emil J. 13:26, 1 October 2010 (UTC)

I find it preferable to just backup the whole directory tree, rather than individual files. Then you don't have to write another script to restore things back to the way they were. --Sean 14:22, 1 October 2010 (UTC)

"A programmer had a problem and decided to work on it by using regular expressions. Then the programmer had two problems." Comet Tuttle (talk) 18:57, 1 October 2010 (UTC)

Regular expressions are the crack of programming. Shadowjams (talk) 20:21, 2 October 2010 (UTC)

Avoiding Javascript timeouts.

I have a complicated JavaScript program and in Firefox, I get a popup that says: "A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete." I know you can have users set: dom.max_script_run_time to make this timeout longer - but this is for general use. I'm putting a 'progress meter' into the script so people can tell when it's going to finish.

Does anyone know what criteria Firefox is using to calculate this timeout? Is there something I could do in my script to reset the timer periodically? (eg Is it enough to stop running - but with a timerevent set that would set things running again a few milliseconds later?) 70.112.128.105 (talk) 17:37, 1 October 2010 (UTC)

Every so often (say every N loops around your main loop) you a) schedule a timer event (setTimeout) to call yourself, and then b) call yield() -- Finlay McWalter ☻ Talk 17:45, 1 October 2010 (UTC)

To phrase it another way: Redesign your algorithm so it does a little work and then goes to sleep. Put the work done in a function. If the function finishes and there is more work to do, use the setTimeout to call the function again. This way, the web browser will see each function call as a separate script running and not one never-ending script. -- kainaw™ 19:22, 1 October 2010 (UTC)

Actually you don't need (js1.7) keyword (my bad, not a function) yield; you just store state in a global variable and return. Here's a simple example that calculates fibonacci numbers without jamming the processor for too long. The key is that it only goes through its main loop itercount times before yielding back to the main event loop (in practice itercount would be a much larger value, probably tens or hundreds of thousands).

javascript source

function main(){ var n = 49; console.log("looking for fib(" +n+")..."); get_fib(n); } var FIB_GLOBALS={}; // a single global to store our persistent state // action to take once the calculation is complete function report_fib(n){ console.log("the fib you asked for is ", n); } function get_fib(n){ if (n==0 || n==1) report_fib(0); else if(n==2) report_fib(1); else { FIB_GLOBALS.alpha=1; FIB_GLOBALS.beta=1; FIB_GLOBALS.count=n-2; calc_fib(); } } function calc_fib(){ var itercount = 3; // absurdly small value for demo purposes while (itercount-- > 0) { total = FIB_GLOBALS.alpha + FIB_GLOBALS.beta; if (--FIB_GLOBALS.count==0) { report_fib(total); return; // success } FIB_GLOBALS.alpha = FIB_GLOBALS.beta; FIB_GLOBALS.beta = total; } setTimeout(calc_fib,0); // yield }

This is a slightly poor example, as we overflow ints long before running into the timeout problem. Can someone think of a very simple algorithm that we can use instead of fib(), that will take a modern computer a few tens of seconds to do, and that won't require bignums or too much code? -- Finlay McWalter ☻ Talk 19:48, 1 October 2010 (UTC)

Thanks! I get the idea. 70.112.128.105 (talk) 00:32, 2 October 2010 (UTC)

VLOOKUP in Excel

I'm working with Excel 2007 (on Windows Server 2003, if that matters...). I'm performing a series of VLOOKUP functions using a formula like this: =VLOOKUP($A3,mattd!$A:$U,16,FALSE) Nothing too unusual there and it works just fine as it's written. What I would like to do is, instead of typing in "mattd" there (the title of one of the worksheets), I'd prefer to lookup that name in a cell. For example, if cell A1 was "mattd" =VLOOKUP($A3,A1!$A:$U,16,FALSE) would lookup the relevant data on the mattd worksheet and if cell A1 was "barts", that same formula would look up the relevant data on the barts worksheet. When I do that, though, Excel is not expecting it and opens a search for another file to look in. Is there a way I can make Excel read the text of a cell and treat it as part of a formula in this way? Matt Deres (talk) 18:10, 1 October 2010 (UTC)

You need the INDIRECT function: VLOOKUP($A3,INDIRECT(A1&"!$A:$U"),16,FALSE), or with A$1 if you intend to copy the formula down the sheet. Bear in mind that as this is an indirect reference, the link will break if you move the lookup table away from the $A:$U range. AspidistraBaby (talk) 19:19, 1 October 2010 (UTC)

Great! That's exactly what I need. Thanks very much! Matt Deres (talk) 20:10, 1 October 2010 (UTC)

Third and fourth hardware questions

This question is slightly related to the two questions I asked above. I switched from the Asus motherboard that I planned to purchase to this one from ASRock. The only problem is that the computer has two PATA/IDE devices -- a hard drive and CD/DVD drive -- and only one port. Yet everything I've read said the one port supports two devices, but nowhere can I find something that tells me how I can plug two devices into the one port. Any suggestions? I thought of ignoring this and buying a $10 IDE-to-SATA bridge. If I did that, would I need to buy an extra length of SATA cable? Please excuse my n00biness, Xenon54 (talk) 23:41, 1 October 2010 (UTC)

All PATA ports support two PATA devices. Make sure you get a PATA cable with three connectors (one for motherboard, one each for the two devices). Typically you use jumpers on the devices to designate one "master" and one "slave" (you can often just use cable select, but some older devices don't do this properly). Plug em in, power up, make the BIOS search for them, then you'd done. -- Finlay McWalter ☻ Talk 23:49, 1 October 2010 (UTC)

October 2

GIS for Newbies

Can someone explain how GIS works in a much simpler way than the article? I find the lead is rather nonspecific whereas the remaining body is overly inaccessible to someone with no knowledge on the topic, at least in my personal opinion. Is it a computer program that stores data based on coordinates or locations on the map? I am not really sure. Are there any good non-Wikipedia websites that offer an intro to what GIS is? Thanks. --128.54.231.9 (talk) 09:06, 2 October 2010 (UTC)

GIS is a field of study. It covers the maths for describing (and converting) geographical locations and relationships, the data formats to store geographical info, and the software to process, change, render, and edit geographical information. -- Finlay McWalter ☻ Talk 10:58, 2 October 2010 (UTC)

Any authoritative, yet simpler introduction to the subject other than wikipedia? --128.54.231.9 (talk) 05:46, 3 October 2010 (UTC)

There's this book, which I haven't read, but which gets a couple of decent customer reviews. I have no idea whether it's simpler than our article. Even if you don't buy the book, the publisher's description might be of interest, as it gives an overview of the subject. --NorwegianBlue ^talk 12:26, 3 October 2010 (UTC)

Uninterruptible power supply

I want to build a UPS. I have an old car battery, would that in combination with a dc-ac inverter be enough to power one desktop computer with lcd screen? How long would it run for? 82.44.55.25 (talk) 16:16, 2 October 2010 (UTC)

Car batteries are not designed to be deeply discharged, or to remain discharged for any length of time because this shortens their life. It would be better to keep you car battery charged with a charger that supplies power at about the same rate as your computer uses it, and rely on the battery only when the mains supply fails. (This is how a purpose-built UPS works, with a circuit that cuts the charging to a trickle when no current is being drawn.) Your dc-ac inverter uses switch-mode circuitry, and there can sometimes be a problem when this is connected to another switch-mode power supply in your computer. My laptop goes "haywire" when I try this, but your desktop might be OK if you have a good quality inverter. Dbfirs 16:49, 2 October 2010 (UTC)

How long would a standard car battery be able to run a desktop computer with lcd screen for? 82.44.55.25 (talk) 10:10, 3 October 2010 (UTC)

Odds

what are the odds of matching any 3 cards drawn from a deck of 52 playing cards with a single card drawn from a separate deck of 52 playing cards —Preceding unsigned comment added by 70.68.31.151 (talk) 17:34, 2 October 2010 (UTC)

There are 52 possible cards and 3 of them have the possibility of matching the original 3. So, 3 in 52 is your odds of getting one of those cards out of the deck of 52. -- kainaw™ 18:29, 2 October 2010 (UTC)

... though, being pedantic, 3/52 is the probability (which was probably what was being asked!) The "odds" are 49 to 3 against. Dbfirs 19:36, 2 October 2010 (UTC)

actually, that's not correct. drawing three cards is drawing without replacement, so your odds probability is 1/52 + 1/51 + 1/50 or .058839 (not the .057692 that 3/52 would suggest). Or so it seems to me... --Ludwigs2 04:50, 3 October 2010 (UTC)

No, Kainaw was right. That second term of 1/51 only applies when there was no match on the first card, so it needs to be multiplied by the probability of that, which is 51/52, giving 1/52. Similarly 1/50 needs to be multiplied by 50/51 and 51/52, again giving 1/52, so this method also produces a probability of 3/52. By the way, the RD/Math#Math desk would have been a better place for this question. --Anonymous, 05:06 UTC, October 3, 2010.

Ah, you're right (on both counts, actually). fair enough. --Ludwigs2 06:41, 3 October 2010 (UTC)

Mac database interface

I'm going to be putting together a rather simple document database, with a fairly small (e.g. probably less than a thousand records) dataset, for a rather elderly person soon, one that runs on a Mac. I haven't looked at the commercial-off-the-shelf database software lately, and wondered if anyone had any opinions as to what would be a good fit.

Requirements:

• Runs on a Mac.
• Pretty straightforward interface for a non-tech savvy person. (Note that I am tech savvy, so it doesn't have to be dumbed down to set up. It just needs to allow me to make a GUI for navigating the data that will be simple for this rather elderly person.)
• Needs to be able to handle PDFs natively. How this might work probably will depend on what is out there. Ideally it'd be nice if they could be viewed from within the database, but if they were externally linked (so they'd open up with Adobe Reader or something), that might be fine.

Free is nice but not required. I could of course labor to create something in MySQL/PHP and then install a MAMP on this guy's machine... but that's probably the most labor-intensive solution and it'd be nice to not have to re-invent the wheel. And it would also make it harder for future people to use, as they'd have set up the MAMP, which is just an extra pain in the neck I'd love to avoid.

Any thoughts? I have not played with OO.org Base for a long time but when I did the interface was clunky and it was pretty slow. I've been thinking about Bento but I've never used it and can't seem to find anything about its PDF capabilities (though I see it has a trial period, so maybe I'll give that a shot first). In a fix, bibliographic software like EndNote might work, though my past experience with them was that they were a pain to use and more complicated than I'd want this to be, but again it has been awhile. Any thoughts? --Mr.98 (talk) 17:35, 2 October 2010 (UTC)

If document management specifically is your goal, perhaps a document management system would be more appropriate than a naked database. I haven't personally used it (but then the for-money DMSes that I have used have been fairly unimpressive) but perhaps OpenKM will meet your goals. It will index a variety of documents, including PDFs. -- Finlay McWalter ☻ Talk 17:40, 2 October 2010 (UTC)

I haven't really looked at DMSes, I'll definitely check them out. Thanks. It looks like the OpenKMS GUI is a bit too scary for my target audience (this guy is not tech savvy), but maybe DMSes in general are a fruitful thing to investigate. --Mr.98 (talk) 01:56, 3 October 2010 (UTC)

Can you give more details about the way this database will be used (e.g., what are the kinds of data that need to be entered, how complex are the operations that need to be run on it, does it need to act as a server or is it a simple one-client db...?). A combination of Spotlight, metadata keys and smart folders can satisfy most simple file-oriented database requirements with minimal effort and an intuitive GUI. --Ludwigs2 18:29, 2 October 2010 (UTC)

FileMaker is popular with Mac users because of its ease of use.--Best Dog Ever (talk) 19:07, 2 October 2010 (UTC)

For mac, FileMaker is most likely what you're after as their isn't a mac version of Microsoft Access.Smallman12q (talk) 00:51, 3 October 2010 (UTC)

All of the FileMaker databases I've looked at in the past are basically big card file stacks. I find that kind of hard to deal with as an interface, personally, being more or less limited to looking at one piece of data at a time. Access is too far on the "pain in the neck" side of things even if it did have a Mac version. (Hence OO.org Base isn't really very appealing to me.) I say this as a very long-time Access programmer. :-) --Mr.98 (talk) 01:56, 3 October 2010 (UTC)

What I'm imagining is a pretty easy database scheme — titles, dates, authors, keywords, some notes, etc. And of course the documents themselves. The whole thing has to be pretty easily searchable. It'd be nice if the interface was something like a search box that then gave you a list of matching records, which could then be clicked on for the information about the record, and a link to the document itself. Pretty basic stuff. One could again whip it up with MySQL/PHP, but only with a great investment of time... It's a very simple model, nothing fancy, nothing even relational. What I'm looking for is more something that will allow me to make something with an easy-yet-powerful interface (not just searching through a stack) with a minimal amount of effort/time investment in setting it up. --Mr.98 (talk) 01:56, 3 October 2010 (UTC)

again, most of this is covered by Spotlight metadata - for instance, I can open a find window in the Finder and search for all PDF documents whose author is X and whose title contains Y, use Quicklook to choose the correct one, open it in Preview for viewing or to make annotations and add spotlight keywords. I can't really see why you need a relational database beyond what the system already offers you. You might need a metadata editor to fix pdf files that lack or have misinformation in their metadata if you're getting your pdfs from sketchy sources, but if you have well-formed files the system is already doing what you seem to want. --Ludwigs2 03:34, 3 October 2010 (UTC)

noindex

My facebook profile used to be within the top 10 for a search for my full name plus the City, State I live in. This concerned me greatly, so into my facebook profile I copied the text
<html> <head> <meta name="robots" content="noindex" /> <title>Don't index this page</title> </head>
hoping that it would remove my facebook profile from google searches. I did this quite some time ago (around 8 months to 1.5 years ago), and when I recently checked for it in search engines I couldn't find it. The only thing is that in the "page info" for my facebook profile url, the only robot orders it states are "noodp" and "noydir". Does one of these work in the same way as "noindex", or am I just lucky that my facebook profile isn't showing up in Google (I notice that other people with my same name's facebook profiles show up in google, but mine doesn't)? Ks0stm ^(T•C•G) 19:44, 2 October 2010 (UTC)

I don't know if Facebook sterilizes user profile content... I would guess they do... however you'd probably be better suited (even if your current approach works now) to change the privacy settings in Facebook itself. One of those allows you to not be listed in public search engines. There are other privacy settings you may be interested in as well. Shadowjams (talk) 20:18, 2 October 2010 (UTC)

Aha, found what you were talking about. This seems to explain why. Now, how do I get it to where I still don't show up in public searches once I turn 18 in a month? Ks0stm ^(T•C•G) 20:23, 2 October 2010 (UTC)

To make your Facebook account not show up on Google: Facebook > Account > Privacy Settings > Applications and Websites > Public Search > Edit Settings > Disable Public Search. They've hidden it good, no? --Mr.98 (talk) 02:07, 3 October 2010 (UTC)

AppleMac 12" laptop, White

The above is running system 9 and the ability to 'drag and drop' has been lost. Any ideas as to how this might be restored please?--85.211.193.110 (talk) 21:08, 2 October 2010 (UTC)

What does it do when you try? I suspect it is a hardware problem (an issue with the mouse or trackpad) and not the operation system. Try hooking an external mouse up to it and seeing if that changes anything. The hardware must be ancient by computer standards if it is running 9. --Mr.98 (talk) 02:11, 3 October 2010 (UTC)

also, which generation Mac is it. a 12" white laptop is most likely an iBook g3 or ibook g4 - if the latter, you could upgrade it to Leopard Tiger relatively cheaply. in os 9 (If I remember correctly) drag and drop was added via a system extension - you could be seeing a corrupt extension or an extension conflict. have you added any new extensions or control panels recently, or added modules to existing extensions? --Ludwigs2 04:45, 3 October 2010 (UTC)

Yes it is an iBook, yes, it is, like me, OLD, but otherwise still useful. I don't use a mouse, just the trackpad. Nothing happens when I try to move an icon, it just stays put and don't move. I have not added any new extensions or control panels.--Artjo (talk) 06:42, 3 October 2010 (UTC)

You forgot to indent using colons. see wp:cheatsheet.

this is kind of hard to diagnose. if you can click on icons then it's probably not a mechanical problem, but you don't normally get random software failures - usually they happen just after you did something or changed something in the system (added a program, changed a setting, etc...). what were you doing just before this problem started happening? --Ludwigs2 06:47, 3 October 2010 (UTC)

Do you own a mouse your could try it with? The point is to try to figure out if there's something wrong with the touchpad (dragging will work with mouse.) or if a software setting has become screwed up somehow. (dragging won't work with mouse either.) APL (talk) 08:00, 3 October 2010 (UTC)

Problem SORTED. Fiddled with extension settings and all well now. Many thanks for your input, much appreciated. --Artjo (talk) 09:29, 3 October 2010 (UTC)

What controls this?

I have a desktop system at home, WinXP on a Dell box, and a similar system at the office, also WinXP but on a different Dellbox. From time to time I decide to clean the junk out of My Recent Documents, usually by exploring to C:\D&S\User\Recent and deleting away.

However, it's also possible to do this with popup menus, and here the two systems operate differently. I assume there's a configuration parameter that drives this, but don't have a clue what to call it or look for.

At Home	At Office
1) Click Start	Click Start
2) Hover to My Recent Documents	Hover to My Recent Documents
3) Slide to a document	Slide to a document
4) RIGHT-click	RIGHT-click
5) Popup menu appears	Popup menu appears
6) Click on Delete	Click on Delete
7) "Are You Sure" dialog appears; click OK	"Are You Sure" dialog appears; click OK
8) "Deleting" dialog appears, then closes	"Deleting" dialog appears, then closes
9) AYS closes	AYS closes
10) Start and Recent menus close	Start and Recent menus stay open
Begin at step 1 for the next file	Begin at step 3 for the next file

Naturally, the sequence of events where the Start menu does not close and needs not be renavigated is preferable. Anybody know what controls this behaviour, and how it can be configured on my home system?

Many Thanks, 97.116.127.118 (talk) 21:45, 2 October 2010 (UTC)

Hmmph. Failed to notice I wasn't logged in, sorry... DaHorsesMouth (talk) 21:49, 2 October 2010 (UTC)

October 3

vids

i need a program that will download vids from sites like metacafe ect. but will preserve the quality. i have the free firefox one but it only works on youtube ( i think)? —Preceding unsigned comment added by Kj650 (talk • contribs) 06:17, 3 October 2010 (UTC)

Try Flashgot. It works with most video sites. I just tried it with metacafe and it worked fine. APL (talk) 07:57, 3 October 2010 (UTC)

Looking up unicode character names from glyphs

I've just seen a series of peculiar glyphs used on a messageboard. Is there a site somewhere with an input box which I can paste a glyph into, which will tell me its unicode name so I can get some idea why it exists? Wurstgeist (talk) 13:11, 3 October 2010 (UTC)