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August 19

Difference between Torrent and BitTorrent

What's the difference between Torrent and BitTorrent? Do torrents refer to the .torrent files while BitTorrent refers to the file-sharing protocol itself? --BiT (talk) 03:35, 19 August 2009 (UTC)

I don't think either of these have dictionary definitions yet. What you are saying sounds fairly right, but I don't think it's incorrect to use them synonymously. Vespine (talk) 04:49, 19 August 2009 (UTC)

Is it maybe possible that the term "torrents" is used for the files themselves while "torrent" and "BitTorrent" may be used synonymously when referring to the protocol? The Wikipedia article doesn't mention this, so I was a bit confused after reading it. --BiT (talk) 05:18, 19 August 2009 (UTC)

BitTorrent can refer to a specific application (as well as a network application), the protocol, and a company. ···日本穣^? · 投稿 · Talk to Nihonjoe 05:29, 19 August 2009 (UTC)

What about simply torrent? Are they completely synonymous? --BiT (talk) 06:13, 19 August 2009 (UTC)

A torrent file is used with BitTorrent software, just as a DOC file is used with Microsoft Word, or an HTML file is used with a Web browser. --FOo (talk) 06:38, 19 August 2009 (UTC)

BitTorrent refers to the company, protocol, and application. Bittorrent is a general term describing the system and community. A torrent is either the individual .torrent file, the files in the swarm that the .torrent file unites, or both concepts together. Mac Davis (talk) 17:22, 21 August 2009 (UTC)

Basic Java

I was wondering if you have create an object with the following code; classA B; B = new classB(); I know that the methods would be overridden but I was wondering how much memory is allocated for object B. I thought the object decleration told the compiler to allocate space in the memory for a new object of classA so does the memory allocated for class A contain the methods in classB or classA or both? Since if both classes have a method randomMethod() and you call it the classB one will override the classA method. 66.133.202.209 (talk) 03:49, 19 August 2009 (UTC)

Let's say 'A' has two fields that are 'int's. One 'int' is four bytes, so that makes eight. There is an object header which is another 8 bytes (I'm assuming a 32-bit Sun JDK). So an 'A' object is total 8+8 = 16 bytes. If 'B' adds another 'int' field, a 'B' object will be 16 + 4 = 20 bytes in size. Methods are not copied for each object, they exist once in memory. If a method overrides another method, there will be two methods, even if you allocate a million of each kind of object. The object header I mentioned above contains a pointer to the object's methods, so the runtime will know whether to call the original method or the overridden one (something like a virtual method table). 62.78.198.48 (talk) 05:29, 19 August 2009 (UTC)

I thought the object decleration told the compiler to allocate space in the memory for a new object of classA No. You have to recognize that classA B; declares a reference (called a pointer in some languages). It does not allocate space for any objects. --Spoon! (talk) 05:58, 19 August 2009 (UTC)

WD My Passport Essential

Hi all; I just bought a Western Digital My Passport Essential external hard drive [1] and I'm wondering if anyone know what type of hard drive it is? Solid state like a USB flash drive or is it magnetic? Thanks —Preceding unsigned comment added by 99.249.132.110 (talk) 05:12, 19 August 2009 (UTC)

Based on the MSRP, I would guess it's a standard platter drive, not solid state. a 500GB solid state drive would likely be more expensive than about $150 USD. ···日本穣^? · 投稿 · Talk to Nihonjoe 05:32, 19 August 2009 (UTC)

I should note that the specifications on the page you link to do not indicate which it is. ···日本穣^? · 投稿 · Talk to Nihonjoe 05:33, 19 August 2009 (UTC)

Well a hard drive is by definition... a hard drive. If it were anything they'd call it something else. --antilived^{T | C | G} 06:20, 19 August 2009 (UTC)

Yes, you're technically correct, but whether a drive is a platter system or uses solid-state memory, people will still call it a "hard drive". Marketing people aren't known for being all that tech savvy, and consumers are even less so when it comes to nitty-gritty details like that. All they care about is if it works; not so much about how it works. ···日本穣^? · 投稿 · Talk to Nihonjoe 06:31, 19 August 2009 (UTC)

It is a laptop-style 2.5" SATA hard disk (the exact Western Digital model number shouldn't be hard to figure out) in a SATA to USB enclosure. 70.90.174.101 (talk) 09:13, 19 August 2009 (UTC)

Beating a Keylogger

The scenario is this: Your internet connection is disconnected. The library and any other publicly accessibly locations where there are computers are closed. You have only one friend.

Today is the day that the Advent Calendar on Neopets is giving out free Super Magical Faerie Double-Bladed Scimitars and hence, it is imperative that you log onto your account and obtain one of these rarities. Your friend is willing to let you use his computer, however, it is installed with a Keylogger.

He wants to steal your account. He already has your account name, but not your password.

As you go to type your password, you type a random garble of letters, then using your mouse, you highlight a portion of the letters, then write over them. You do this continually for, say, 5 minutes until you have entered in a total of several hundred letters and numbers. Your password is formed from the leftover letters that you did not erase. Since your friend does not know how long your password is, nor which letters you've erased, nor which portion of the inputted letters/numbers you have erased, will this be an effective strategy to combat a Keylogger?

Thanks. Acceptable (talk) 07:19, 19 August 2009 (UTC)

Depends if there is a mouse and screen logger as well, or an internet or browser data logger. Graeme Bartlett (talk) 07:26, 19 August 2009 (UTC)

This is a pretty artificial situation, but I'll take it at face value and suppose that there is only a keylogger and nothing else. In that case you can certainly hide your password. For example, for every possible password character in some canonical order, type that character, copy it to the clipboard, then paste it back in the appropriate location(s) using mouse actions. -- BenRG (talk) 09:17, 19 August 2009 (UTC)

There is no way to prevent your "friend" from logging every input event (keyboard, mouse, screen) that goes through the computer so he can later replay everything you saw on your screen and everything you did. If Neopets lets you log in with (say) OpenID, you could enroll beforehand with an openid service that uses one-time passwords, or otherwise lets you lock out your account (say by attempting 3 logins with the wrong password) after you have ordered your scimitar. Higher security sites like Paypal will let you enroll a hardware authentication token (keychain gizmo with an LCD display showing a number that changes every 30 seconds, that you type in instead of a re-usable password) but these aren't widely deployed. Basically your best bet for this scenario is to carry your own computer that you've somehow assured yourself is free of loggers, and also be sure that Neopets uses an encrypted (TLS) socket to receive your password, so that your friend can't sniff it from the network connection. 70.90.174.101 (talk) 09:24, 19 August 2009 (UTC)

If your friend is not around, boot into safe mode, disable the keylogger, reboot. I know, boring. --98.217.14.211 (talk) 01:39, 20 August 2009 (UTC)

What you need is to find a website with a high turnover of text...the Wikipedia "Recent changes" page for example. Open one browser window there and the other to the NeoPets site. Use the mouse/keyboard to cut/paste individual characters from the Wikipedia page into the NeoPet's password area to spell out your password. Neither keylogger nor mouse logger can store what was on the web page at the time you did your cut/paste operation - so replaying your mouse moves and keystrokes won't work because the Wikipedia page now has different text on it. I suppose you should flush the browser cache at some point...just to be really sure. SteveBaker (talk) 02:47, 20 August 2009 (UTC)

Start > Programs > Accessories > System Tools > Character map? —Preceding unsigned comment added by 148.134.37.3 (talk) 15:03, 20 August 2009 (UTC)

Float

I need an help with the float comand. In a project external to wiki but based on wiki software I need to float a table with other taables around it but it doesn't run. Is there a solution? Thank you very much.--F.noceti (talk) 12:30, 19 August 2009 (UTC)

"float" in this context is the cascading style sheets float property. That's a powerful, but often difficult to use feature (when you have more than very basic requirements). I'd recommend you work through a css-float tutorial like this one. It's not specific to Mediawiki. -- Finlay McWalter • Talk 12:33, 19 August 2009 (UTC)

You might also read Wikipedia:Reference desk/How to ask a software question to help us help you better. --Sean 15:26, 19 August 2009 (UTC)

Thank you very much. Iwrite as single person (with my real name) but i work with an equipe and I think that we've found the right way for our target. Thank you very much for your help! --F.noceti (talk) 20:14, 19 August 2009 (UTC)

Light spreadsheet tool?

Is there some kind of 'light' spreadsheet tool, focusing solely on manipulating data structurally? I mean, I only use excel and openoffice for some really basic purposes: to clean up spreadsheets, convert between formats, and visually do text-to-columns conversion. So it'd be really cool if I have something fast, and memory sparing, to do just that.--Fangz (talk) 13:29, 19 August 2009 (UTC)

Visicalc was very light and can be downloaded for free. --80.176.225.249 (talk) 20:54, 19 August 2009 (UTC)

Perhaps something in the List of spreadsheet software would be what you are looking for. 89.241.32.157 (talk) 21:37, 20 August 2009 (UTC)

I would personally recommend Google Docs:

It's fast and simple and won't consume too much resources.

custom url

In Firefox, I need a way to automatically change a specific url to another one when a page loads. So for example instead of wikipedia loading http://en.wikipedia.org/skins-1.5/chick/main.css it would load http://mysite.com/custom.css when I view the page. Any ideas how to do this? —Preceding unsigned comment added by 82.43.89.136 (talk) 13:47, 19 August 2009 (UTC)

I imagine this is the sort of a thing a greasemonkey script could do, but which would work only for you. I guess there are a range of scripting method to do this from the server. --Tagishsimon (talk) 13:57, 19 August 2009 (UTC)

I only need this for me. The problem is the website I wish to view is having trouble and it's css files aren't loading. I have a offline copy of the css file, I just need a way to implement it when I view the page. —Preceding unsigned comment added by 82.43.89.136 (talk) 14:03, 19 August 2009 (UTC)

Then greasemonkey is your friend. I've never used it so cannot offer advice on operation, but it sounds as though it'll be at the very simple end of GM's capabilities - it's just an on-the-fly string replacement in an HTML file. --Tagishsimon (talk) 14:05, 19 August 2009 (UTC)

Thanks, but I don't know how to put my .css file into greasemonkey. —Preceding unsigned comment added by 82.43.89.136 (talk) 14:27, 19 August 2009 (UTC)

I'd have thought that the CSS would stay on your drive, and you'd have a greasemoney script amend the CSS references in the incoming HTML files to point at your CSS. Here's a manual for GM which might help to orientate your thinking. --Tagishsimon (talk) 14:31, 19 August 2009 (UTC)

Here's a GM script that does what you want:

// ==UserScript==
// @name           ChangeCSS
// @namespace      http://greasemonkey-question.com/
// @include        http://the-site-you-want-to-modify/*
// ==/UserScript==

(function() {

    // The format is:
    //      "bad-URL"
    //          : "good-URL"
    var url_map = {
        "http://en.wikipedia.org/skins-1.5/chick/main.css"
            : "http://mysite.com/custom.css",

        "http://en.wikipedia.org/skins-1.5/chick/some-other.css"
            : "http://mysite.com/my-other-thing.css"
    };

    var links = document.getElementsByTagName('link');
    for (var i = 0; i < links.length; ++i)
    {
        var link = links[i];
        var new_url = url_map[link.href];
        if (new_url)
            link.href = new_url;
    }
})()

--Sean 16:03, 19 August 2009 (UTC)

You are my hero Sean! You always come along and help me with this sort of stuff! Once again, thank you :D —Preceding unsigned comment added by 82.43.89.136 (talk) 16:16, 19 August 2009 (UTC)

Thanks for the nice compliment, but I only do it because I'm supposed to be working. :) --Sean 16:37, 19 August 2009 (UTC)

Rotating PDF pages

Hi. Is there a free tool (preferably graphical) for Windows that can rotate PDFs? It only needs to do 90 degree rotations, typical use would be for portrait/landscape orientation of single page graphs. You would think this would be the most obvious task in the world, but Googling for "rotate pdf" brings up a crapload of rubbish and some expensive PDF editing software. On a second point, why don't the standard PDF readers (Adobe, Foxit etc.) support page rotation AND SAVING? The documents always open up in their original orientation even if you choose to "save as.../save a copy..." after rotating it. Regards, Zunaid 13:58, 19 August 2009 (UTC)

pdftk can rotate 90º... it's command-line but pretty easy to use.

As for why they don't support it... Adobe doesn't because they want you to buy professional. Foxit, I don't know. They ought to. I'm still waiting for the open source people to decide that a lightweight, free version of Adobe Professional is worth their while—something that would let you easily rotate pages, OCR them, move pages around in files, etc... the code to do all this is out there (e.g. pdftk), but nobody's put it into a useful GUI, as far as I know. --98.217.14.211 (talk) 14:31, 19 August 2009 (UTC)

Thanks! Got it and it's working perfectly, after a bit of tweaking and hassle. For anyone else who hates the command line and JUST wants to rotate pages (clockwise) from the comfort of Windows Explorer, follow these instructions:

1. Download pdftk.
2. Extract pdftk.exe to your favourite directory (let's call it "C:\Windows")
3. Create pdftk.bat in the same folder as above with the following contents:

@echo off
pdftk.exe %1 cat 1-endR output poknmihytfx.pdf
move /Y poknmihytfx.pdf %1

In the above code, the poknmihytfx is simply a place-holder name since pdftk doesn't allow you to overwrite files (in the next line you move poknmihytfx over the original file anyway). The %1 refers to the input file (the PDF you want to rotate), cat is the pdftk command for catenate, 1-end means "select page 1 to the last page" and R means "rotate the page RIGHT i.e. clockwise".

Now comes the tricky bit:

1. In Windows Explorer go to Tools --> Folder Options. Then click on the "File Types" tab.
2. Find you pdf file type in the list, click on "Advanced", then click on "New".
3. For "Action:" give it a descriptive name like "Rotate Clockwise".
4. Under "Application used to perform action:" enter the following: C:\Windows\pdftk.bat %1, where the C:\Windows refers to the folder you initially create pdftk.bat in.
5. Click on OK all the way out. You should now be able to right-click on any PDF file and to rotate it clockwise from the pop-up menu.
6. The above WILL NOT WORK if you are using Adobe Reader 9 as your default PDF viewer, its screws up the PDF file associations, I managed to get it working by deleting lots of PDF stuff out of the registry, but I see I've lost the PDF preview in the explorer window as a result. YMMV.

I'm leaving this open for now, would still like to know if there's a graphical tool out there. Zunaid 18:20, 19 August 2009 (UTC)

Why not just copy and paste everything (from the default pdf viewer) into another tool? Or capture the screen and paste into any number of graphical editors? Sandman30s (talk) 21:23, 20 August 2009 (UTC)

Because those approaches only work either on graphics-only PDFs or really on single-page PDFs. To try and rotate every page of a multi-page PDF in, say, Photoshop, is ridiculous, as it can only handle one page at a time, and then you still have to use some other tool to merge them together again. Editing PDFs in graphics editors is *NOT* really editing the PDF -- it's rasterizing a page of a PDF as a bitmap image, and then maybe converting that to a PDF. It is not a substitute for a program that can edit PDFs quickly and natively. (I find that the people who suggest it don't really deal with PDF manipulation on a regular basis... it is very, very impractical, which is clear if you try to do it more than once.) --98.217.14.211 (talk) 20:25, 23 August 2009 (UTC)

My forward button is no longer blue

The details of my computer are in a previous question I asked. This [2] is where the question was answered but the link to the question doesn't work now.

I clicked the back button many times since I've been doing a lot. The forward button just turned gray and wouldn't let me go back to where I was, so I had to just keep going back.Vchimpanzee · talk · contributions · 16:46, 19 August 2009 (UTC)

The "forward" button will turn gray and cease to function if you click anything on a web page other than the "back" and "forward" browser buttons. Tempshill (talk) 17:10, 19 August 2009 (UTC)

I know, but I'm pretty sure I didn't. Do you know how to find the previous, related question?Vchimpanzee · talk · contributions · 17:35, 19 August 2009 (UTC)

The two best ways are to search for "Vchimpanzee" using the search box at the top of this page, and, alternatively, to use Google and search for vchimpanzee reference desk site:en.wikipedia.org and see if that comes up with anything better (I see 104 results). I think your previous problem had been that the Back button had turned gray, which is a different problem (it occurs when a new page or tab is created, for example). Tempshill (talk) 18:06, 19 August 2009 (UTC)

There was a way to search for my questions on Wikipedia, but I made a mistake and ended up with a search engine that couldn't find the address starting with http, and then when I tried again, all it would give me was http://http://[url].

But the back button turned gray even when there was supposedly something to go back to. It's the same thing here and I'm trying to understand what happened.Vchimpanzee · talk · contributions · 19:18, 19 August 2009 (UTC)

It worked. Here is the information about my computer:[3]

Sorry, does that mean that the problem is now fixed? Tempshill (talk) 19:24, 19 August 2009 (UTC)

And here [4] is my older question on this subject.

No, I'm trying to figure out why what happened this morning happened.Vchimpanzee · talk · contributions · 19:25, 19 August 2009 (UTC)

I have to assume you clicked something within the web page (or possibly hit a key on the keyboard, which can count as a mouse click to the web designer). When working on Wikipedia or elsewhere, I try not relying on the Forward button remaining viable; it is a fragile way to work. If you need specific pages to refer to, did you know you can create a new browser window by hitting ctrl-N ...then you could copy and paste the URL from the first window to the second window, and then you can switch between the two windows as needed, and not rely on the Back and Forward browser buttons as much. Tempshill (talk) 21:05, 19 August 2009 (UTC)

Assuming you are using Internet Explorer then you could press Ctrl-H which will bring up the list of web pages viewed. Choose the "View by order visited today" option. Find the page you want and click on it. 89.241.32.157 (talk) 19:19, 20 August 2009 (UTC)

HP Notebook running Vista won't shutdown

My new HP Pavilion Notebook PC running Windows Vista Home Premium won't shutdown when on AC power. It simply restarts instead. I have found that it will shutdown normally only when on battery power. HP Tech Support seemed not to be aware of this problem, thought my OS was corrupted and had me do a complete Windows Restore. The symptom remained after the restore. Is there a fix for this? --Thomprod (talk) 16:59, 19 August 2009 (UTC)

How are you shutting down? Are you hitting the physical power button on the laptop, selecting the turn off button on the start menu, or are you specifically selecting "shut down" from the submenu by the turn off button? —Akrabbim^talk 18:20, 19 August 2009 (UTC)

I have tried the two latter options, both of which result in a restart rather than a shutdown. --Thomprod (talk) 18:24, 19 August 2009 (UTC)

Is this a brand new laptop, or has the problem just recently cropped up? System restore would only work if the restore point was set up before the problem emerged. A fresh reinstall may be necessary if that is the case. If that doesn't work, I would guess that the problem is in the hardware or bios or something, where a 'shut down' command is being interpreted as a 'restart' command. —Akrabbim^talk 18:31, 19 August 2009 (UTC)

This is a brand new laptop. --Thomprod (talk) 01:06, 20 August 2009 (UTC)

Simple Answer: Unplug the notebook before shutting down.

That's my current workaround. --Thomprod (talk) 01:06, 20 August 2009 (UTC)

Long and Complicated Answer: I have had this happen before on XP. Most likely, an HP-provided driver for some AC power management is causing Vista to crash on shutdown. If you had XP, i would tell you to go to the Control Panel>System>Advanced and click on settings under "Startup and Recovery" and uncheck the "Automatically Restart" box. However, I have no experience with Vista. Try googling "automatic restart on shutdown in Vista."  Buffered Input Output 22:27, 19 August 2009 (UTC)

Dell Startup Problem

Resolved

I have a Dell Dimension 8250 desktop computer (it's ~5 years old), and when I turn it on it displays a black screen with a command prompt cursor in the upper lefthand corner, and that's all it can do anymore. No Dell or Windows XP startup screens. What's causing the problem, and what is the solution? All the diagnostic lights are green ("no problems"), and the manual doesn't address this problem. Tried putting in a Windows XP reinstall disk but the computer doesn't run it. Bonus question: what's a fair price to sell this computer if I can't get it to work? How about if I can? Thank you very much for any help you can give. ~EdGl ★ 19:08, 19 August 2009 (UTC)

Try unplugging any USB devices you have and see if that makes any difference. Possibly it's a bad USB device, but I believe the Dell code for that is Yellow/Green/Yellow/Green which you're not seeing. As for selling it... no offence intended, but a 5 year old, non-working computer... I'd be surprised if you could even give it away :( ZX81 ^talk 19:55, 19 August 2009 (UTC)

Finally got Windows XP to reinstall, woohoo! Anyway, as for resale, I assumed at least some parts/accessories (e.g. monitor) would be worth something... ~EdGl ★ 22:04, 19 August 2009 (UTC)

You could have tried selling it on Ebay (with honest description of the problem) - I've spend some time earlier this year trying to find a replacement screen for my (4.5y old Dell Inspiron 510m) that way. Going price for a dead laptop with working screen was about £40.195.128.251.195 (talk) 22:22, 19 August 2009 (UTC)

C/C++: optimal use of fread() and fwrite()

I'm writing a program that splits huge files into suitable chunks, and a corresponding program that reassembles these. Doubtlessly, others have done this before, but there are a couple of tweaks that I want to include, and I think I'll spend less time writing my own than finding a program that does exactly what I would like it to do.

I first tried the naive approach, fputc and fgetc, thinking the compiler would take care of the buffering. The files are pretty large (40Gb and upwards). I was absolutely amazed at how long time this took - ten to twenty times as long as a simple file copy to the same USB device. The program was compiled in release mode with Microsoft Visual C++ 6.0.

So obviously, fread and fwrite are the way to go. I want the program to be as fast as absolutely possible, and did some experimentation with fread and fwrite, with encouraging results.

fread and fwrite have the syntax:

size_t fread( void *buffer, size_t size, size_t count, FILE *stream );
size_t fwrite( const void *buffer, size_t size, size_t count, FILE *stream );

I will allocate the buffer using an std::vector<char>.

I am writing here to ask for advice on what values to select for size and count in each read and write operation, in order to archive optimal results.

• Does it matter whether I ask for one block of 1048576 bytes, 1048576 blocks of one byte or 1024 blocks of 1024 bytes, and if so, which choice is preferable?
• I assume that it's a good idea to avoid that the data being read is swapped to the hard disk before it is written to the device, so I suppose the size of count * size should be smaller than the amount of available RAM. Correct?
• Is there a simple way (with the MSC++ 6.0 compiler) to determine the amount of free RAM?
• What would be sensible choices for count and size on a Windows XP PC with 520Mb RAM, 1Gb RAM and 2Gb RAM (assuming no other applications are running at the same time)?

Thanks, --NorwegianBlue ^talk 19:44, 19 August 2009 (UTC)

You might consider reading mmap(). Our article covers mmap and its Windows alternative, MapViewOfFile(). These methods will allow the compiler (rather the operating system's runtime library) to do the buffering for you. When you use low-level standard IO calls like fputc(), you are specifically requesting unbuffered reads and writes - so the compiler should not optimize those with a buffering scheme. In Java, the New IO (java.nio.*) package, (documentation) and its Channels methodology, allow you to do the same - with the VM overseeing the demand paging and swapping of buffers into and out of memory. I have yet to find a more efficient method for reading gigabyte- and terabyte- size files than Java NIO. (I attribute this to intelligent pre-buffering based on the VM's reasonably accurate assessment of when and where you will leap to in the file next). Nimur (talk) 20:17, 19 August 2009 (UTC)

[f]getc and [f]putc are buffered. I assume the speed problem comes from the constant checks to see whether the buffer is full/empty, combined with the inherent inefficiency of a byte-by-byte memcpy(). -- BenRG (talk) 20:58, 19 August 2009 (UTC)

My mistake - I was confusing the memory copy, which is single-byte-at-a-time. It seems BenRG is correct. Nimur (talk) 21:07, 19 August 2009 (UTC)

Hm - I can't find a good standard library call to determine the amount of available physical memory in C (and I don't even remember ever learning it!) In Java, you can call Runtime.getRuntime().freeMemory() - with the caveats that (a) this is an estimate, and (b) this is only the maximum memory allocatable to the JVM (not total free system memory). In C, the convention I have always used is to malloc() and check for NULL; if failed, wait-and-retry or exit. I don't know if it's good design methodology to try to allocate exactly as much memory as is reported available - so be sure to use some "margin of error". Nimur (talk) 20:30, 19 August 2009 (UTC)

In C#, or C++ .NET, you can use a PerformanceCounter - MSDN documentation and example in C#. Nimur (talk) 20:39, 19 August 2009 (UTC)

Ah - here's what you want - Win32 API GlobalMemoryStatusEx(). This is the most portable version (for Windows computers) and works at the lowest level of abstraction. Nimur (talk) 20:44, 19 August 2009 (UTC)

It seems like the standard way to get the current memory status on linux is to check the values in /proc/meminfo (which can be accessed like a file, although it is not a regular file). I'd be curious if some more expert linux systems guys have better insight - surely there's a system call? Nimur (talk) 20:55, 19 August 2009 (UTC)

You shouldn't be allocating huge buffers. The buffer just needs to be large enough that the system call overhead (some constant * file size / buffer size) is negligible. 64K should be more than large enough for that. It doesn't matter how you split it between count and size—the C library just multiplies them together. What's really important when copying between different devices is that the reading and writing happen in parallel. If they alternate it will cut your speed in half. On the read side, you want the OS to do readahead; on the write side, you want write-back caching, not write-through. There's probably nothing you can do about the write-side caching. Windows uses write-through caching on USB devices by default, because people have a tendency to yank them out as soon as Explorer says their files are copied. I seem to recall that reading large chunks can cause NT to disable readahead, so this is another reason to use small chunks (but maybe I'm thinking of Win9x). Annoyingly, there is a reason you might want to write large chunks: it will decrease fragmentation because NT will search for a large contiguous region of free space when you use large writes. You can avoid this problem by preallocating the file, but you only want to do that on NTFS: on FAT I think it will cause the whole file to be written twice (the first time with zeroes). I would stick to small chunks.

If you want to get fancy, the fastest way to do disk I/O in NT is overlapped I/O. The idea is that instead of the read/write function returning when it's done, it returns immediately and then later you get a completion callback. Between your request and the callback the OS owns your buffer and you can't touch it. The advantage is that when you have several requests pending the OS can schedule the I/O better because it knows what's coming; it doesn't have to guess. To use overlapped I/O, allocate two or three buffers (maybe a megabyte each?) and start read requests on them, then go into a wait state (using SleepEx). When you get a read completion callback you trigger the corresponding write; when you get a write completion callback you reassign the buffer to another part of the file and trigger a read. Everything is single-threaded, so you don't have to worry about synchronization. It's actually quite easy and it will perform optimally regardless of FAT/NTFS and caching and so on. The main problem is that it's NT-specific. -- BenRG (talk) 20:58, 19 August 2009 (UTC)

Java NIO also implements a platform-independent asynchronous IO: [5]. Nimur (talk) 21:03, 19 August 2009 (UTC)

If I was committed to getting the best performance out of vanilla reads and writes, I would use a binary search to get the biggest chunk of memory malloc() would give me, and then do another binary search on the best buffer size (benchmark each). The second number is probably pretty stable on a given platform, so I'd cache the result in a file somewhere. --Sean 01:47, 20 August 2009 (UTC)

Using large blocks and multiple asynchronous I/Os allows the system to do good disc scheduling. This means it may read or write the blocks in order of where they are on the disc rather than logically in the file, this cuts down seek time which is a major component of file copy times. Dmcq (talk) 08:54, 20 August 2009 (UTC)

Thanks everyone for lots of good input! I think the OS-dependent simultaneous read-and-write calls will require too work much for this job (I will need to port this to Linux afterwards), and be risky, because removable media are involved. My reason for wanting to select as large a buffer as possible, was exactly what Dmcq pointed out, but the buffer still ought to be smaller than the available RAM, no? I didn't understand Seans suggestion for using malloc to estimate free RAM, I thought malloc used virtual memory, not necessarily physical RAM. --NorwegianBlue ^talk 12:11, 20 August 2009 (UTC)

Oops, you're right of course; too much time in kernel land.  :( --Sean 14:56, 20 August 2009 (UTC)

Asynchronous I/O is not risky. If the output device is configured for write-through caching then the writes won't complete until they are done. It's no different from an ordinary synchronous write. In fact, when you do a synchronous write on NT it just does an asynchronous write and then waits for it to complete before returning. But stdio will work fine if you want to stick to plain C. You may as well try benchmarking different buffer sizes as Sean suggested, but large buffers (more than a few megabytes) are a bad idea; they won't help performance and probably will hurt it. -- BenRG (talk) 19:04, 20 August 2009 (UTC)

Boost has a cross-platform asynchronous I/O library: boost asio. --Sean 14:58, 20 August 2009 (UTC)

Thanks again. Copying 40Gb to a 64Gb memory stick using a buffer size of 512Mb took approximately 80 minutes (including calculation of MD5 sums of each chunk). The memory stick was FAT32, and empty, but the file I copied from (a file which holds a truecrypt volume, unmounted of course) was rather badly fragmented.

Regarding fragmentation, the defragger that comes with WinXP was unable to do anything about it. I defragmented the disk before allocating the 40Gb file, but the program was happy as long as the individual files were contiguous. It's not like in the olden days, when the Norton utilities defragmentation tool maximized contiguous free space. When I tried to defragment the disk after allocating the volume, it just gave up, even if 25% of the disk was still unused. I think I'll move the 40Gb file to external media, fill the disk up with moderately large dummy files (4-8Gb?), and try to defrag again.

Anyway, I strongly suspect that the limiting factor is the write speed of the memory stick. According to this review, writing 1.8 Gb took 8.45 min, which should correspond to 40Gb taking 188 min, so I beat the test in the review by a factor of 2.3. Therefore, there's probably little to be gained in attempting further improvements. I liked the boost thing, though, I think I'll have a look into it just for the fun of it. --NorwegianBlue ^talk 00:51, 21 August 2009 (UTC)

Why are you using a 512MB buffer? I told you in both my responses that large buffers would hurt performance, and you ignored me. A buffer that large will disable all of the OS's caching mechanisms, leaving one device or the other idle virtually all of the time. If your faster device is k times faster than your slower device then performance with a huge buffer will be about k/(k+1) of optimum. For equal read and write speeds that's a 50% reduction. The Fudzilla review is obviously wrong about the speed as your result demonstrates. Searching the web I find quoted figures ranging from 8 to 17 MB/sec. You're getting 8.5 MB/sec.

There's no reason to use XP's bundled defragmenter. There are free alternatives that are better, like JkDefrag. Use one of them instead of trying to coerce XP's defragmenter into doing what you want. -- BenRG (talk) 10:30, 21 August 2009 (UTC)

Boost makes heavy use of generic programming, so gird your loins for the compilation error messages, which are sadly not going away anytime soon. --Sean 12:11, 21 August 2009 (UTC)

@BenRG: I didn't ignore you. My first test was with a 512MB buffer. You and Dmcq gave conflicting advice, and Dmcq's advice was closer to my prejudices than yours was, so I tried that first. An increase from 8.5 to 17 MB/s would be most welcome. I am planning to test the performance with both a smaller and a larger buffer (it turned out that the source PC had a lot more RAM than I thought). I'll be back with more results! And thanks a lot for making me aware of JkDefrag!

@Sean: Heh,heh, I know. I've used some of the boost libraries in previous projects. Painless on linux, except for the error messages. A bit more problematic on Windows, as I stubbornly insist on using an ancient compiler. --NorwegianBlue ^talk 13:45, 21 August 2009 (UTC)

Here's why you should be differently prejudiced. When you call fwrite it has to copy all of your data somewhere else before returning since you might modify the buffer as soon as it returns. It either has to physically store it on the device or copy it to an OS-owned buffer. But no OS is going to allocate 512MB of kernel memory to store your data. At most it will allocate a few megabytes, so most of your data will have to be written during the fwrite call. When calling fread you have the same problem in reverse. It has to fill the buffer before returning, either from cache or from the device. You only read the data once, so the only way anything will be in cache is from speculative readahead. But no OS is going to read ahead 512MB. At most it'll read ahead maybe 256K, so almost all of the physical reading will have to happen during the fread call. Since there will never be an fwrite and an fread in progress at the same time in a single-threaded application, one or the other device is sitting idle for the vast majority of the overall runtime. On the other hand, if you use a 64K buffer then writes will copy the data to kernel memory and return immediately and reads will copy the data from the readahead cache and return immediately. The actual reading and writing will happen in the background, simultaneously on both devices. There are three reasons you might want to write larger chunks: to reduce seek times (not an issue when copying between devices), to reduce fragmentation (not an issue on flash drives) and to avoid redundant filesystem metadata updates (possibly an issue on flash drives). If you use overlapped I/O you're no longer relying on kernel buffering, so you can use larger buffers (where larger means, I dunno, 16MB) and get the best of both worlds. 512MB is insane. There's no need to test it because there's no situation in heaven or earth where it would be a sensible choice. Try sizes between 64K and 1MB and go with whatever's fastest. -- BenRG (talk) 14:57, 21 August 2009 (UTC)

Thanks a million for spelling it out in crystal clear detail. I understand, and am convinced. I'll modify my program, and do the tweaking in the 16-256kb range instead of the 128Gb-2048Gb range. I'll do some benchmarking. I hope to get the time in the week-end, and hope to be able to be back with the results before this thread is archived. --NorwegianBlue ^talk 16:55, 21 August 2009 (UTC)

I realise you have your program working now, but the standard utility for cutting a large file up into convenient-sized chunks is split (Unix). There will surely be versions available for Windows.-gadfium 23:07, 21 August 2009 (UTC)

Thanks. As I stated at the beginning of the thread, the reason I do this at all, is that there are a couple of tweaks that I would like to include (blockwize md5 sums being the most important). Moreover, I don't want to type a bunch of parameters, just

                mysplit SOURCEFILE DESTFILE_NO_EXTENSION
                and
                myjoin SOURCEFILE_NO_EXTENSION DESTFILE

I know, of course, that avoding command line parameters can be solved by writing a script/bat-file. I tried the the md5 checker I had available on the original 40Gb file. It was insanely slow (I don't know exactly how slow, as I didn't have the patience to wait for it finishing, but we're talking MANY hours). I'm on a different computer now, so I can't check exactly which md5 checker it was. Probably the md5 checker will behave better on the smaller chunks than on the 40Gb file. I have cygwin (which includes split) installed on my home computer, but not on the source computer for this project. I'll include split when I do the benchmarking. --NorwegianBlue ^talk 10:27, 22 August 2009 (UTC)

You can set your I/O to work unbuffered and asynchronous and then you can use multiple large buffers. This is almost equivalent to doing memory map operations. Dmcq (talk) 11:26, 22 August 2009 (UTC)

Benchmarking

I checked out the source code for Split (Unix) here. It uses a buffer size of MAXBSIZE for each write. Googling has given values for MAXBSIZE of 32k, 56k and 64k, in good agreement with BenRG's recommendations. The most time-critical part of this project, is the transfer of data from the harddisk to the USB stick. Since the write speed of the USB stick is vastly slower than the read speed of the harddisk, I reckoned it would make sense to determine the ideal block size for achieving the fastest possible write speed to the USB stick, so I wrote a program to that purpose. I did this benchmarking on a rather old (2004-2005) AMD64 XP PC with 1Gb of RAM. I killed every killable process in the task manager, stopped AVG, but kept the Visual C++ IDE alive while the program was running in a DOS box. The program wrote a 3Gb file from a RAM buffer to the USB stick. In case anyone is interested, here is the program:

Click "show" (at the right side of this box) to read the program! Please note that the program has been slightly "tidied up" before being posted, and that errors may have crept in! #include <io.h> #include <string> #include <vector> #include <iostream> typedef __int64 LongLong; typedef unsigned char Byte; typedef FILE* FILE_POINTER; const FILE_POINTER NULL_FILE = 0; const long SIXTY_FOUR_KILOBYTES = 65536L; const long TWOHUNDRED_FIFTY_SIX_KILOBYTES = 262144L; const long ONE_MEGABYTE = 1048576L; const long TWO_MEGABYTES = 2097152L; const long FOUR_MEGABYTES = 4194304L; const long SIXTEEN_MEGABYTES = 16777216L; const long SIXTY_FOUR_MEGABYTES = 67108864L; const long ONENUNDRED_TWENTY_EIGHT_MEGABYTES = 134217728L; const long TWOHUNDRED_FIFTY_SIX_MEGABYTES = 268435456L; const long HALF_A_GIGABYTE = 536870912L; const long ONE_GIGABYTE = 1073741824L; // --------------------------------------------------------------------------------- //#define BUFFER_SIZE SIXTY_FOUR_KILOBYTES //#define NUM_ITERATIONS 49152L //#define BUFFER_SIZE TWOHUNDRED_FIFTY_SIX_KILOBYTES //#define NUM_ITERATIONS 12288 //#define BUFFER_SIZE ONE_MEGABYTE //#define NUM_ITERATIONS 3072 //#define BUFFER_SIZE TWO_MEGABYTES //#define NUM_ITERATIONS 1536L //#define BUFFER_SIZE FOUR_MEGABYTES //#define NUM_INTERATIONS 768L //#define BUFFER_SIZE SIXTEEN_MEGABYTES //#define NUM_ITERATIONS 192L //#define BUFFER_SIZE SIXTY_FOUR_MEGABYTES //#define NUM_ITERATIONS 48L //#define BUFFER_SIZE ONENUNDRED_TWENTY_EIGHT_MEGABYTES //#define NUM_ITERATIONS 24L //#define BUFFER_SIZE TWOHUNDRED_FIFTY_SIX_MEGABYTES //#define NUM_ITERATIONS 12L //#define BUFFER_SIZE HALF_A_GIGABYTE //#define NUM_ITERATIONS 6L #define BUFFER_SIZE ONE_GIGABYTE #define NUM_ITERATIONS 3L // ================================================================================= // Helper class: Self-closing file // ================================================================================= class File { FILE* m_filePointer; std::string m_fileName; public: File(); ~File(); void open_for_reading(const char* name); void open_for_writing(const char* name); int fileHandle(); FILE* filePointer(); const std::string& fileName(); // Disallowed: File(const File&); // Not implemented File& operator=(const File&); // Not implemented }; File::File() : m_filePointer(NULL_FILE), m_fileName("<File has not been opened>") { m_filePointer = NULL_FILE; }; File::~File() { if (m_filePointer != NULL_FILE) { fclose(m_filePointer); } }; void File::open_for_reading(const char* name) { m_fileName = name; m_filePointer = fopen(name, "rb"); } void File::open_for_writing(const char* name) { m_fileName = name; m_filePointer = fopen(name, "wb"); } FILE* File::filePointer() { return m_filePointer; } // ================================================================================= // file_exists() // ================================================================================= bool file_exists(const std::string& name) { File f; f.open_for_reading(name.c_str()); return (f.filePointer() != NULL_FILE); } // ================================================================================= // Write Three GB. // ================================================================================= bool write_3_GigaBytes(const char* fileName, Byte* buffer) { File f; f.open_for_writing(fileName); if (f.filePointer == 0) { std::cerr << "Error opening file: " << fileName << '\n'; return false; } long j; for (j = 0; j < NUM_ITERATIONS; ++j) { int st = fwrite(buffer, BUFFER_SIZE, 1, f.filePointer()); if (st != 1) { std::cerr << "Error writing block number " << j+1 << " to file: " << fileName << '\n'; return false; } } return true; } // ================================================================================= // Write Marker file // ================================================================================= void write_dummy_file(const char* fn) { File f; f.open_for_writing(fn); } // ================================================================================= // Main // ================================================================================= int main(int argc, char* argv[]) { if (argc != 2) { std::cerr << "Syntax: write_benchmarking FILENAME\n" << argv[1]; exit(2); } if (file_exists(argv[1])) { std::cerr << "Error: file exists: " << argv[1] << '\n'; exit(2); } const char* fn_start = "F:\\just.about.to.start.writing.3GB"; // Note: For convenience, I've hard-coded the drive letter of the USB stick here const char* fn_done = "F:\\finished.writing.3GB"; // Note: For convenience, I've hard-coded the drive letter of the USB stick here Byte* buffer = (Byte*) malloc(BUFFER_SIZE); if (buffer == 0) { std::cout << "Out of memory!\n"; exit(2); } long i; for (i = 0; i < BUFFER_SIZE; ++i) { buffer[i] = (i & 0xff); // Whatever... } write_dummy_file(fn_start); // This file's time stamp is equal to the time when writing the big file starts. bool ok = write_3_GigaBytes(argv[1], buffer); if (! ok) { std::cerr << "Something went wrong when writing the 3 GB file " << argv[1] << '\n'; } write_dummy_file(fn_done); // This file's time stamp is equal to the time when writing the big file finishes. if (buffer != 0) { free(buffer); } return 0; }

I ran each combination of buffer size and number of iterations twice. The results were repoducible - with the same parameters, the results were virtually identical. Here are the results:

 64 kB buffer:   6.0 MB/sec
256 KB Buffer:   8.2 MB/sec
  1 MB buffer:  10.1 MB/sec
  4 MB buffer:  10.5 MB/sec
 16 MB buffer:  11.0 MB/sec
 64 MB buffer:  10.8 MB/sec
128 MB Buffer:  11.0 MB/sec
256 MB buffer:  10.8 MB/sec
512 MB buffer:  10.8 MB/sec
  1 GB buffer:   7.6 MB/sec

It seems as if the write speed, on this particular computer, levels out at about 16MB, but the difference between 1MB and 16 MB is tiny, and it may well be that the disadvantages that BenRG has pointed out, will make a choice of 1MB more sensible. The fact that performance doesn't drop when buffer sizes reach "insanely" high levels, indicates to me that the OS may allocate more physical RAM than what BenRG expected. I promised to compare performance to Split (Unix), but will not have time to do so before this thread is archived (benchmarking takes a lot of time). If it turns out that Split outperforms my tailor-made program, however, I will humbly be back with a post linking to this one, entitled "Reinventing the wheel", with the results. --NorwegianBlue ^talk 20:55, 23 August 2009 (UTC)

I've been checking out some internet forum such as this one. As our article also states, writing data to a flash drive, implies that a large amount of disk space has to be erased, for a large drive typically 2MB, as indicated in the external link. Hence, I conclude that 2MB is probably the ideal buffer size for the application I'm working on. Note also that performance starts to drop only at a buffer size of 1GB. To me, this indicates that no swapping to disk is going on when 512MB is malloc'ed (after all, win XP can run acceptably on the remaining 512MB).

I also tested the benchmarking on a much faster computer with 4Gb RAM today. It performed slightly poorer than the figures I have quoted above (but I was unable to disable its anti-virus software). --NorwegianBlue ^talk 18:40, 24 August 2009 (UTC) 17:45, 24 August 2009 (UTC)

GPU Clock and Memory Clock

Hello there, I want to know something graphics cards clock. what is the differences between GPU Clock and Memory clock? Which one increases the temperature of Graphics card? In order to avoid overheat issue which one should be decreased? GPU clock or memory clock or both? (Please do not ask me to use diagnostic tool to check overheating). Thank you--119.30.36.36 (talk) 20:25, 19 August 2009 (UTC)

Overclocking your GPU will cause the GPU to heat up more. Overclocking your graphics memory will cause the graphics RAM to heat up more. Since your RAM probably does not have a thermal shutdown safety, this is more likely to permanently damage your hardware. As far as which overclocking scheme will improve performance, it depends whether your graphics operations are memory- or compute-bound. This will depend very heavily on the specific game, tool, or application you are running; and the ugly nitty-gritty details like your current graphics card, GPU series and core model, current device driver; and CPU load and bus load. Nimur (talk) 20:41, 19 August 2009 (UTC)

• I dont want to overclock. My GPU Clock is 850MHz and Memory clock is 975MHz. So which one is responsible for system overheating and freeze while playing game and browsing net (I have freezing problem in both)? You said "graphics operations are memory- or compute-bound". I don't understand it. Can you please elaborate which application requires memory or computer bound? thanks--119.30.36.36 (talk) 21:06, 19 August 2009 (UTC)

What evidence is there that the graphics card is the cause of the problem? And why bother asking questions here if you refuse to use the obvious diagnostic tool to determine if it is? 87.113.69.234 (talk) 23:27, 19 August 2009 (UTC)

You haven't told us what graphics card you are using, so there is no way for us to know whether those clock speeds exceed the norm for those chips. You also haven't told us whether you have already tried to overclock the GPU or the GPU memory, or whether this is merely a concern of yours based on something you read. Tempshill (talk) 00:01, 20 August 2009 (UTC)

• My graphics card is XFX ATI Radeon 4890 1 GB. I have never tried overclocking GPU or GPU memory. I have freezing issue and tried ALL (using diagnostic tools, blowing fan, changing chasis etc. etc) the necessary steps to prevent it. Unfortunately, I have come to know that GPU Clock or Memory clock increases this heat issue which causes freezing. My other devices are ok. There is no way to get the card replaced. If I reduce GPU Clock do I also need to reduce memory clock. I am planning the following activities:

• Reduce GPU Clock from 850 MHz to 800 MHz (5%)
• Reduce Memory Clock from 975 MHz to 925 MHz (5%) (if required)

Should I only stick with GPU clock in order to get rid of overheating problem?--119.30.36.54 (talk) 15:12, 20 August 2009 (UTC)

Those are the stock frequencies according to this page. If your card can't run stable at stock frequency you should go and exchange for a new one. --antilived^{T | C | G} 20:09, 20 August 2009 (UTC)

One further question. How exactly are you certain that it is your system temperature that is causing the lockups? It's a clever idea to think of underclocking the graphics card in order to reduce the system temperature, but I have never heard of anyone doing this, and I would think it's far more likely that your unstable system is due to a software problem or some hardware problem that won't go away merely by lowering the temperature by a couple of degrees from stock. If you're certain that it's the temperature that's causing this, you'll need to run through with us all the steps you've tried so we don't lecture you about this sort of thing, sorry. Improved heat sink on the CPU? Improved fan on the heat sink of the CPU? Improved case fans? Tempshill (talk) 21:44, 20 August 2009 (UTC)

• My card can run at stock frequency. But problem is sometimes it lockups during browsing (mouse pointer and keyboard stop working for a while then work and again stop. Music gets crashed if play while browsing. All symptoms happen if system runs for several hours). I use USB Modem.

Previously, I had overheating problem. At that time system got frozen within 5 to 10 minutes during playing game. I took my card to the shop where bought it. Everything went fine there as they have air conditioned room. So I changed pc case and get full tower case with better cooling system and it almost solved system freezing while playing game. My room temperature sometime raises and sometimes lowers (since I live in warm country) which easily enter into pc case. But I can't get rid of "system locks up problem while browsing".

One more thing I can't get my graphics card exchanged unless I prove the problem to the shops technician. I have to prove it which I am facing in home, but I failed. They told me to disable system restore point but nothing happened. --119.30.36.40 (talk) 07:16, 21 August 2009 (UTC)

It sounds like the same problem you had before - which I thought was due to a serial device overheating - probably due to the overall heat levels in the machine. Would a portable air conditioner for the room be an option (should cost less than either your graphics card or cpu).

Still it doesn't make much sense that your system is ok for games, and not for browsing - games should make it hotter83.100.250.79 (talk) 10:55, 21 August 2009 (UTC)

It might not be heat hardware problem, but with a 4890 I really think you need to get the room temperature below 20C - it's not really a mass market part. (By the way do you have another graphics card, or integrated graphics on the motherboard - if so does the computer run ok with these.)83.100.250.79 (talk) 11:07, 21 August 2009 (UTC)

Also find out which chip on the motherboard handles serial devices - make sure that air flow to cool it is not being blocked by wires etc.83.100.250.79 (talk) 11:23, 21 August 2009 (UTC)

• I don't have much money to buy portable air conditioner (since I invested all of money to new hardware). I have graphics card but it is not PCI 2.0 motherboard supported. It is 5 years old. Is my USB Modem incompatible with motherboard? Is it also causing overheating? What is least option to stop this lockup problem? Reducing GPU or memory clock?

Pc case has better ventilation which provides sufficient air flow to motherboard. Wires are placed aside to mobo.--119.30.36.34 (talk) 13:34, 21 August 2009 (UTC)

Mac Apps on Windows

I like Windows the best and I"m running it on my Mac with VirtualBox. But there are some Mac apps I like. How can I run Mac apps in Windows like how one can run Windows software on a Mac with Parralell's Coherence? --Melab±1 ☎ 20:31, 19 August 2009 (UTC)

You can't, basically. Apple doesn't allow emulation of Macs on non-Apple hardware. The closest you can do is a thing called Hackintosh... but it's not the easiest thing to set up, and not really what you are asking for (which isn't "how do I install OS X on a Windows machine"). --98.217.14.211 (talk) 01:24, 20 August 2009 (UTC)

I think that OSx86 (same link as Hackintosh) will run in VirtualBox and VMware and the like, but it's probably illegal. -- BenRG (talk) 10:38, 20 August 2009 (UTC)

Archive of some sort

I might have posted something like this earlier, but i don't remember and now i have more information.

The file is named main.cat and is used by a game. No tools are given to open the file and the game is pretty much nonexistent. When opened in a hex editor (HHD Hex Editor Neo Free), the first four characters come out to be "CAT1". This is not the same as a Security Catalog header (I checked) and HHD Hex Editor Neo identified it as a possible RAR archive. But neither WinRAR nor 7Zip could open it as an archive, and Game Extractor Basic couldn't do it either.

The characters near the end of main.cat correspond to files that are used by the game (like NAPALM.WAV, TITLE.XM, and so forth) with some offset bytes between them. I am assuming that the middle section of the file is some sort of compressed data (it's gibberish, btw) but i cannot identify the compression scheme.

I've tried to extract with several programs, with no luck. If anyone with knowledge of the "CAT1" header or knows what i'm rambling about, please don't hesitate to respond! ANY help at all is appreciated! Thanks!

 Buffered Input Output 22:20, 19 August 2009 (UTC)

I gather that you are trying to get some kind of data from the file. What is your objective here? What is the name of the game? Tempshill (talk) 00:02, 20 August 2009 (UTC)

If the game authors had wanted you to get at the data, they'd have made it easy. Since they didn't, they obviously don't intend for you to mess with this file - and almost certainly made it virtually impossible by writing the file with some kind of unpublished custom tool. SteveBaker (talk) 02:35, 20 August 2009 (UTC)

I don't know why you'd call it "virtually impossible"; you must know that people routinely reverse-engineer these formats for modding purposes. This one doesn't even sound very difficult, given that the filenames are in plaintext. If it does use compression there's a good chance it's zlib, since rolling your own data compression is a lot harder than rolling your own archive format. If it uses some other compression then you might have to disassemble the game executable to figure it out. -- BenRG (talk) 10:59, 20 August 2009 (UTC)

Whoops, I spoke too soon. The data wasn't compressed, but was more or less just stored. I could have probably done it a simpler way than I did; I hex-edited the file and extracted what I wanted (and backed up the original just in case). Yayz! Thanks for your help!  Buffered Input Output 00:40, 23 August 2009 (UTC)

August 20

Midnight ana/cron job

Is there any way to ensure that a cron job, which is also checked by anacron, takes place at midnight if possible? The reason is that I need to update dynamic tables in a database that depend on the date but not on the time of day. NeonMerlin 01:23, 20 August 2009 (UTC)

Macintosh code merging tool?

Can anyone suggest a Macintosh code-merging tool, something like Emacs emerge-mode if you're familiar with that? Basically something that diffs two source files, and puts up a three-pane window, with files A and B side by side, and the merged result underneath. It highlights the diffs between A and B and lets you move through the two files choosing which side to take each diff from, copying your choice to the merge window, and eventually you save the merged result in a new file. This is for use by my officemates who use Macintoshes. I don't use Macs myself so don't have much idea what's out there but I'm pretty sure such things exist. Thanks. 70.90.174.101 (talk) 02:01, 20 August 2009 (UTC)

There are Unix tools such as tkdiff which can do this, and which should run fine on the Mac. --FOo (talk) 03:20, 20 August 2009 (UTC)

I like Meld the best. Here is a Mac package of it. --Sean 15:10, 20 August 2009 (UTC)

If you want to attack the problem before it happens, Subethaedit, a collaborative programming tool, is very good. Mac Davis (talk) 17:15, 21 August 2009 (UTC)

Tool for writing (wiki?)

I'm a bit overwhelmed by the availability of various tools and not really quite sure how to pin this down - I'm torn between thinking it should be a text editor (OpenOffice Writer, SciTE) or a wiki (MediaWiki?) or a web service (scribd?). I'd like to non-collaboratively write a story with some sort of logical break (chapter, page) but utilize a lot of wiki-esq features - versioning, and more importantly what I understand to be backlinks (?) and hopefully some form of *auto*link (so, for example, every instance of "Harry Houdini" automagically substitutes itself to (link to Harry Houdini notes page)Harry Houdini(/link), whose page has those backlinks ibid, and "diff". Setting up an Apache/MySQL/PHP stack isn't a challenge - finding the right tool is. Or even the search terms to sift through, as "authoring wiki" and vice versa conflate in meaning. Pointers would be appreciated. 69.255.26.5 (talk) 03:49, 20 August 2009 (UTC)

Perhaps you should look at using DocBook as the markup language, and keep all the files in Subversion or CVS? It has all the formatting features for writing a book, and has the ability to include links to references. -- JSBillings 11:40, 20 August 2009 (UTC)

Printing a mail with no Header

I'm trying to print a message from my Microsoft Outlook inbox, I want the print out to contain only the body of the message and none of the fields such as To, From, Name etc. Just wondering if this is Doabl? Thanks - Foz 80.88.241.94 (talk) 09:09, 20 August 2009 (UTC)

I'm guessing there's a reason you don't want to do this in another application? If you don't care you just need to highlight the text copy (Control+C) and then open up Word/Notepad/Whatever and paste it (Control+V). You can then print it with only the information you want. 09:19, 20 August 2009 (UTC)

Actually there is a good one, Copy-Paste for some reason is not working properly, it's cutting out some lines.. have tried everything i could think of to fix this, with no success. So now trying to think out of the box! Foz 80.88.241.94 (talk) 09:58, 20 August 2009 (UTC)

Perhaps rather than copy/paste you could do some kind of "save as text" (I don't have Outlook, so I'm guessing), and then edit the text file? --Sean 15:13, 20 August 2009 (UTC)

How to connect to localhost using putty ?

How to connect to localhost using putty (telnet / ssh session) in windows / cygwin environment ? thanks in advance. --V4vijayakumar (talk) 14:14, 20 August 2009 (UTC)

Same as any other host; just use "localhost" as the hostname. You'll need to have an SSH server running, of course. --Sean 15:13, 20 August 2009 (UTC)

Also consider connecting to the IP address 127.0.0.1 (or really 127.any.num.ber) in case localhost would somehow not resolve or be redirected in hosts.txt. IP addresses begining with 127 loopback to the local machine under RFC 3330. Freedomlinux (talk) 22:26, 20 August 2009 (UTC)

Using games software for animation

Some users have tweaked games software to create "3D" video animations, shown on YouTube. I do not play those kind of games, and I know nothing about animation. What software can I use to create similar animations please? 78.149.149.64 (talk) 14:56, 20 August 2009 (UTC)

See Machinima. --Sean 15:15, 20 August 2009 (UTC)

In the past (circa 2002) to hack Halo PC we used an older, differently named version of Autodesk 3ds Max. You'd create a "skin," another design for a tank or gun. This would only change how things looked, not how things acted. To actually change the functionality of something you'd open up a hex editor and tweak the parameters. This way you can get invisible characters and infinite speed rockets. To make machinima, you can just hookup your Xbox or whatnot to your PC with a video capture card and record video like that, adding voice overs and doing some light video editing to get your finished product. Mac Davis (talk) 17:12, 21 August 2009 (UTC)

Specific question about wikis

A wiki I made running Semantic MediaWiki has a page with an #ask function that creates a sortable table. The page in question is here. Now, if I choose to sort the list by the property "Debut", the Guard article is sent to the top, even though its property should place it after Zay-Kessa. This seems to be because the page its property links to does not exist. Short of creating the page, how can I stop this happening? (Note that stopping the property from creating links will not work, as I need the links.) Anthrcer (click to talk to me) 15:48, 20 August 2009 (UTC)

Unexpected restart and error log

Hello there, suddenly my system restarted automatically when I connected my usb modem to usb port. When desktop appears a message pop up which is something like "The system has recovered from a serious error. A log of this error has been created. For more information about this error, click here". I clicked on the link and following message appeared: BCCode : fe BCP1 : 00000004 BCP2 : 89B2A008 BCP3 : 8933CA74 BCP4:00000000 OSVer:5_1_2600 SP:2_0 Product : 256_1. I clicked on technical information about the error report and it showed following 2 files which will be added to the error report:

• C:\DOCUME~1\nahid\LOCALS~1\Temp\WER5eb2.dir00\Mini082009-01.dmp
• C:\DOCUME~1\nahid\LOCALS~1\Temp\WER5eb2.dir00\sysdata.xml

What was this sudden restart and what about this error report and files?--119.30.36.39 (talk) 18:41, 20 August 2009 (UTC)

It is likely that your USB modem's driver is poorly written and it crashed the computer. If you experience no further crashes and the modem is functional, I'd forget about it and go on with your life. If it continues to crash, update its driver using the manufacturer's website, and if that doesn't fix it then contact their technical support service; and if none of this helps, then return the modem and buy one from a manufacturer with better drivers. By the way, this sort of crash is more common by far under Windows XP and previous editions than it is under Windows Vista and, presumably, the upcoming Windows 7, both of which use a different driver model that makes it harder for poorly written drivers to crash the whole machine. Tempshill (talk) 21:39, 20 August 2009 (UTC)

High Resolution Settings and Browsing

I have a 1920x1200 display and while browsing the internet I notice I have to increase the text size a lot to make things legible. However when I do this the formatting of the pages tend to get screwed up and I can't see a lot of the text. What's the best way to browse full screen web pages on a high resolution display?

I use firefox if that makes a difference. TheFutureAwaits (talk) 18:45, 20 August 2009 (UTC)

Try increasing the font size(DPI) of your operating system...it's generally available in the advanced section of your display properties(os dependent)Piyushbehera25 (talk) 19:26, 20 August 2009 (UTC)

Newer versions of Firefox (I think 3 onward) have an option where instead of just increasing the text size (which throws layouts out of whack), it will zoom the entire page (so the images increase in size as well). I don't know if that is advisable but it's an easy thing to play with. --98.217.14.211 (talk) 19:34, 20 August 2009 (UTC)

For a quick and dirty fix, if there is just some small text you can't read, hold down "control" and move the mouse "scroll wheel". This does also get formatting out of whack, but it's good if you just want to make something large for a moment to read it then put it back to normal again. I think this works on most browsers. Vespine (talk) 05:35, 21 August 2009 (UTC)

Right, but this is actually the problem. I keep having to press control and scroll to increase website sizes since at their native size they only take up the middle third of my screen. But then when I zoom in I lose a lot of the information contained on the bottom of the page. Is there some way I can just expanded the horizontal size of the page to fill up my screen? TheFutureAwaits (talk) 08:46, 21 August 2009 (UTC)

Research Issues in Routing

Hi,

I'm a final year B-Tech(undergrad degree) student in Computer Science...i'm intrested in carrying out research in the Computer Networks field(esp in Routing). As i'm from a small college there isn't much exposure to currently undergoing research in the above said topic. If any one can suggest me any research issues(in routing) to work on I would be very grateful to them...Also it would be very helpful if you could point out any sites or other resources which are related to the Routing...Thanking you in advance...Piyushbehera25 (talk) 19:22, 20 August 2009 (UTC)

I can't suggest anything specific, but if no one responds with any good ideas, here's what I'd suggest: search for Routing on Google Scholar. As an undergrad, you may find some of the papers there overwhelming, but if you dig around, you'll probably find some things that look interesting. That'll give you a starting point; you can look up papers that that one references, or you can also look at the authors' faculty web pages, where they usually talk some about their current research programs. Cbogart2 (talk) 09:43, 24 August 2009 (UTC)

Privacy when using a PC

I'm currently using an XP computer attached to an old CRT monitor. I'm in the UK - not sure if this means the monitor works using PAL like UK non-digital tvs, or NTSC like old US tvs, or something else. But my question is - could someone in the next room with little or no equipment pick up the image from the monitor or elsewhere, even if a very noisy image? Years ago I think I remember I could get the ghost of an image from my computer on a nearby tv if I fiddled with the tuning - not sure if that still holds. 89.241.32.157 (talk) 21:22, 20 August 2009 (UTC)

You are using neither NTSC nor PAL, which as you know are television standards and not computer monitor standards. Your CRT monitor is using a variety of the VGA standard. I have never seen the ghost of a CRT image on a nearby CRT or TV. If you're paranoid about spies, you may become more so when you read our TEMPEST article, which concerns shielding such electronic equipment to prevent nearby snoopers with special equipment from spying on what's on your monitor. Tempshill (talk) 21:31, 20 August 2009 (UTC)

Also Van Eck phreaking to freak you out even more. Vespine (talk) 01:40, 21 August 2009 (UTC)

In general the answer is no. I think - the signal will leak a little, but there will be so much electronic noise they'd definitely need specialist expensive equipment.

However as you note - it does sometimes happen that the 'moons align' and a weak signal can be amplified, and appear fairly clearly elsewhere - the problem is probably more pronounced with analogue signals

However with an directional aerial (built for VGA frequency communications) connected to a high frequency amplifier connected to a monitor it may well be possible to pick your signal - however the limit here is knowledge, not cost. And they'd still need some specialist equipment. Maybe someone else could verify the validity of this listening method?83.100.250.79 (talk) 21:04, 21 August 2009 (UTC)

August 21

When was the first Whitehouse email?

I'm trying to figure out when the first "email" was sent or received by the Whitehouse. I've found lots of other milestones (first email, SMTP history, whitehouse website history, etc.) but not the actual date that a president, or their whitehouse staff, had access to email in the building. Ronabop (talk) 06:13, 28 August 2009 (UTC)

Looking for a nutrition web site

I originally posted this Q on the Science Desk: Wikipedia:Reference_desk/Science#Looking_for_a_nutrition_web_site. It was suggested I cross-post to here.

I'm looking for a site which will list foods which are good for diabetics, those with high blood pressure, those with kidney failure, etc. No big deal ? Well, I want it to recommend foods for those with multiple medical conditions. (Note that I'm not asking anyone here to recommend any foods, just a site where I can look it up myself.) Ideally you should be able to weight the medical conditions, say if you only have slightly high blood pressure but have severe diabetes. In that case avoiding foods with a high glycemic index would be more important than avoiding salt. It should also list foods from best to worst, for the given medical conditions and weighting factors.

The Best Buy web site can do something similar with appliances right now. You give it some parameters, like the size of monitor, it's resolution, and cost range, and they give you a list of monitors that match, then they can sort by, say, the current price. The same thing could easily be done with foods, where the parameters become low glycemic index, low salt, etc. The site nutritiondata.com already has this info, I just need it to be made "searchable" and "sortable". So, does such a site exist, or must I create it myself ? If so, is there a way to extract the data from an existing site and add searchable and sortable columns to it ? StuRat (talk) 00:44, 21 August 2009 (UTC)

Categorization tool/bot

I want to add several categories to existing articles on a major scale. For instance, adding [[Category:Gram positive bacteria]] to all Staphylococcus articles. Is there a tool or bot that can help? I've searched WP:BOTS, WP:TOOLS, and the searchable archives for this talk page to no avail. - Draeco (talk) 07:22, 21 August 2009 (UTC)

WP:AWB. ---— Gadget850 (Ed) ^talk 12:50, 21 August 2009 (UTC)

Mediawiki error

So I have been getting this annoy error, it first popped up when I tried to use the Social Profile with Mediawiki 1.15.1, then in a desperate attempt to see if it was because the software was incompatible due to age or something I updated to 1.16 and then when that failed I did a shits and giggles attempt and installed 1.16WMF (which comes with the most recent version of the extension). The error is "Warning: Parameter 1 to incEditCount() expected to be a reference, value given in ****\w\includes\Hooks.php on line 132"

The extensions I used can be found here.

This error happens with ANY AND EVERY extensions that has to use Hooks.php. Please note that I have deleted the Hooks.php and replaced it a number of times and the error makes editing impossible by happening after an attempt to confirm an edit is made.Rgoodermote  07:28, 21 August 2009 (UTC)

Is there a search engine or program that can manipulate row/column arrays?

Many web sites have tables of numeric row coumn data. For example, imagine a nutrition table with rows of foods and columns of nutrient contents for each food. Does anyone know of a program that could manipulate any recognizable website data array like a spreadsheet, so that you could sort the rows by the values in a specific column? alteripse (talk) 11:50, 21 August 2009 (UTC)

Note that this is related to my nutrition Q, 3 questions up. StuRat (talk) 12:04, 21 August 2009 (UTC)

It sounds a bit fiddly or problematic without <td id="???"> or <td name="???"> tags - is it possible to assume that it uses tags such as these (ie the standard HTML Document object model)?83.100.250.79 (talk) 12:54, 21 August 2009 (UTC)

It would be trivial to write a greasemonkey script to do this with the tags, less so, but still possible without83.100.250.79 (talk) 12:56, 21 August 2009 (UTC)

If you are writing the web page from scratch then it should be easy to use javascript to create a sortable table using the tags described above.83.100.250.79 (talk) 15:48, 22 August 2009 (UTC)

Unfortunately, the idea is to extract the info from an existing web site, and we can't rely on them having those tags there, either. StuRat (talk) 19:39, 22 August 2009 (UTC)

MySQL -- from scratch to database in how long?

I know this is highly subjective, but I'm just looking for a rough estimate.

My personal background: master's degree in science, HTML literate, learned CSS this past Spring without difficulty, comfortable in Dreamweaver CS4, no real programming language experience, maintained a personal website as a hobby for years

My goal: Add a searchable, sortable, expandable post-launch database with upwards of 200+ binary (yes/no) variables for each entry to my existing website.

Tools at hand: Learning PHP, MySQL, and JavaScript: A Step-by-Step Guide to Creating Dynamic Websites by Robin Nixon + whatever info I can find online.

Basically, this dbase has been a dream project of mine for a few years and I've finally got time to pursue it. Hosting is a non-issue, as I've already got a lovely plan with all the extras I need. I'm here to ask about time. Not knowing a lick of MySQL, I am wholly unable to estimate how long it will take me to get up to speed and how simple/complex my dbase idea is compared to other MySQL applications (I'm guessing "not very")... the upside of the project is that daydreaming about it for several years has resulted in a rock-solid task list, with no possibility of feature creep.

Anyone out there wanna take a shot at this? 100 manhours? More?

Thank you, 61.189.63.183 (talk) 12:03, 21 August 2009 (UTC)

If you want an accurate estimate, you need to give us that rock-solid task list. For example, how does the data get entered, updated, and accessed ? All through the web site ? And how much data is there ? StuRat (talk) 12:09, 21 August 2009 (UTC)

Yes, more info needed. The hardest part about a database is getting the data in it. If, for example, you already have the tables filled out in Excel spreadsheets, turning that into a functional database takes not very long at all. If you have to put together complicated data entry tools, though, that takes 90% of the time. MySQL itself is generally dead easy, because you aren't doing that much with it (add a row, get a row, compare value X to value Y, etc.). It's the PHP, Javascript, etc., that you are making work with the MySQL that takes time. The database is the easy part—it's just a bunch of values in a table—the application is the time-consuming part. --98.217.14.211 (talk) 12:40, 21 August 2009 (UTC)

OP here. I was planning on having the data updated via a form on the website, but could certainly do it via Excel spreadsheets. This is the part of the plan that I can't speculate on because I don't have any experience with anything other than HTML & CSS. As far as data structure, each entry is a unique name and then a simple has/hasn't checkbox for a LOT of variables. I'm guesstimating 200+ right now, but each actual entry will probably never have more than ~40 checked boxes (yeses). Because the data entry will be brutal no matter how you slice it, I was hoping to make that available online for multiple people to input together. So I guess the database would have 2 access methods - browsing & editing/updating. As for searches, I just want visitors to be able to check as few or as many of the same variables as they wish, and then have the dbase spit out every entry that contains those variables. (chocolate AND vanilla AND nuts AND low-fat...) Because everything will be binary (yes/no), I'm imagining this aspect being relatively simple. Please ignore any urges to get sidetracked about the usability of the system - that can come later! Right now I'm just looking for a rough estimate. More info, if necessary, can be provided. 216.93.191.240 (talk) 13:14, 21 August 2009 (UTC)

In my experience, unless you have a bunch of slaves who are happy to do the data entry no matter how you set it up, you will be best served by spending some time thinking about what an intuitive way to enter all that data in would be. Hint: clicking on Yes/No checkboxes is NOT a good way to do it -- it is time consuming and much more difficult than, say, keyboard-based approaches. Coming up with a good interface is a MUCH harder programming and design task than the database.

Your database structure is pretty simple (though there are a few different ways you could do it—depending on the specifics of the data, which I can't tell from your description). Setting up a MySQL database can be done very quickly if you get a GUI program for it, like phpMyAdmin. You could probably have the basic data structure up and running in a few hours. Setting up the PHP to access the database is pretty straightforward if you follow the instructions in your book (and don't try to just guess your way through it—there are specific ways things are done and orders things should be done it). So I would say, setting up a bare-bones proof-of-concept probably would take, oh, maybe 20 hours total, assuming you are able to learn and debug your work at a modest pace. (For someone more familiar with the tools, it would take maybe 1-2 hours, but there's a learning curve in this as in everything). Developing something more user-friendly, that would take maybe 100 hours, assuming you are not a Javascript whiz already (Javascript is your friend for creating good interfaces, but it takes a little time to learn how to use it appropriately as well). --98.217.14.211 (talk) 16:42, 21 August 2009 (UTC)

Thank you for taking the time to post, everyone. 216.93.191.240 (talk) 23:02, 21 August 2009 (UTC)

Word Processing - half a line

In the usual suspects, is there a way to easily insert half a line feed. eg between two paragraphs to have a blank line that is only half the standard blank line. Specifically I'm thinking is there a way to make it easy to insert as well eg CTRL+Enter = Line feed 1.5 ? 83.100.250.79 (talk) 12:10, 21 August 2009 (UTC)

In MS Word, the way you'd generally do this is select the paragraph in question, then go to Format > Paragraph. There is a section that says "Spacing"; set the "After" to whatever the equivalent of 1.5 lines is at your font size (it is in points; so if it is 12pt, try 18pt). --98.217.14.211 (talk) 12:44, 21 August 2009 (UTC)

Thanks, I can't find an equivalent in open office - is setting "spacing below paragraph" to be >0cm the way to do it? Or have I missed a better option?83.100.250.79 (talk) 12:51, 21 August 2009 (UTC)

Yes, it is probably that. --98.217.14.211 (talk) 17:02, 21 August 2009 (UTC)

Directly below the "Below paragraph" is "Line Spacing" and a drop box where you can choose 1.5 lines. -- kainaw™ 14:32, 21 August 2009 (UTC)

I want extra lines after the paragraph, not in it.83.100.250.79 (talk) 14:35,

Then, increase the spacing either "Before paragraph" or "Below paragraph" as mentioned. You can alter the style itself so you don't have to manually do it to each paragraph. -- kainaw™ 21:07, 21 August 2009 (UTC)

21 August 2009 (UTC)

More:line feed without carriage return

A way to do this ?83.100.250.79 (talk) 12:51, 21 August 2009 (UTC)

Vertical proportional printing/justification

Is this possible (eg within a text box), does it have a proper name?83.100.250.79 (talk) 12:51, 21 August 2009 (UTC)

HDR

How do High dynamic range imaging and High dynamic range rendering work? The respective articles are a bit too heavy on the jargon for me. 69.77.202.90 (talk) 13:23, 21 August 2009 (UTC)

The short version is that HDR combines three images taken at different exposure settings. Using photos as an example, most digital cameras have a range of five stops - which means that you can have detail in the dark areas or detail in the light ones, but not both at once. Thus the camera normally picks something in the middle, allowing the mid range to look good, but not the two extremes. You normally see it with dark areas where you can't really make out what's in them and a "blown out" sky that just looks like an expanse of white. With HDR you take three pictures, one with a short exposure showing the light areas, one with a long exposure showing the detail in the dark areas, and one in between (the photo you would normally take). Then you combine the three, giving a picture that shows detail throughout. - Bilby (talk) 13:44, 21 August 2009 (UTC)

The rendering (of three photos into one) takes place by comparing the three photos pixel by pixel, this is why the three must be EXACTLY the same shot, at various exposures. The minimums in the short exposure (the too dark shot) and the maximums in the long exposure (the too bright shot) are thrown away and replaced with a more balanced value from one of the other two shots. The process is deceptively simple, but obtaining a good balance of what is 'too dark' or 'too bright' is sometimes difficult, leading to advantages in certain applications that use more complex algorithms. This is why HDR is most often used as a silly effect filter as opposed to a serious technique to improve a scene. --66.195.232.121 (talk) 13:54, 21 August 2009 (UTC)

(This is the answer for High dynamic range rendering, the first sort is different and given above.)

A typical computer monitor has ~256 scales of grey going from 0 black to 255 white.

In the real world light intensities vary much more eg the light in the sun is 1000 times brighter than indoors light (eg a lightbulb looks very dim when turned on during the day)

High dynamic range rendering calculates the light intensities at the higher scale (ie a big range of numbers typically with a intensity range of greater than 1 to 1billion actually even more)

However though the computer can stored these numbers (ie the calculated light intensities) for each pixel, a computer monitor can't display them.

To get round this the values are scaled back to fit inside the 0-255 range. (basically divide by a big number so that the most intense lights match 255)

(The scaling isn't always linear - can be logarthymic.) - in fact the way the big light intensity values are scaled is an important part of making computer HDR work well.

Ask if you require more expansion.83.100.250.79 (talk) 13:49, 21 August 2009 (UTC)

Windows mail password prototection?

My wife and I both use the same login profile for windows vista. When I (or she) click on 'Windows mail' my inbox automatically comes up. She logs into her hotmail email via the web. Is there any way I can put a password on windows mail so she can't get into my email. I love her dearly but I need a little privacy for the next few weeks. I don't want to give her a whole new vista profile to log into (that might make her suspicious) but I would like to stop here accidentally getting at my mail.58.170.109.8 (talk) 13:55, 21 August 2009 (UTC)

Sorry, but as far as I know you can't. Because Vista (and XP for that matter) are setup with the ability for people to make their own Windows user profile this is why the option doesn't exist in Windows Live Mail as it's expecting the security to be handled by the login itself (i.e. password protect the Windows account). ZX81 ^talk 14:16, 21 August 2009 (UTC)

Just remove the account info from Windows Mail (if possible) and use webmail for the next weeks? Or start a Gmail account to get all the info about the super-secret surprise anniversary vacation (or whatever your secrets are) sent there instead? Jørgen (talk) 17:45, 21 August 2009 (UTC)

Install Windows Live Mail. It's an upgrade for Windows Mail, and you can set it so that a a password is required everytime. Warrior4321 19:18, 21 August 2009 (UTC)

Another alternative might be to move windowsmail.exe (or whatever it's called) from wherever it lives now to C:\super\secret\location. Then clicking the icon won't work, but you can still go and manually start it. --Sean 19:32, 21 August 2009 (UTC)

The path is "C:\Program Files\Windows Mail\WinMail.exe". But moving the file might not work (you can try, though). However, my personal opinion is that every person using a computer should have her own user account. Always. --Andreas Rejbrand (talk) 20:38, 21 August 2009 (UTC)

I agree - it's not really even about privacy, it's about accuracy. If the computer says "Joe has mail", you won't know whether Joe or Joe's wife, daughter, cat, or sentient robot (who share the same account) actually need attention. The computer has no way to distinguish individual users, except in the form of login-accounts. If you want to make data shareable between different users, that can be arranged on most modern operating systems (including Windows); but the computer can still treat accounts separately. The sentient robot part isn't so far from the truth. This actually happened to me this morning - cron, which was incorrectly running in a user-account on spacenimur was sending email to nwmoussa (me, the human), when it should have been sending it to the ntp-daemon - just this morning! Unfortunately, I didn't know what to do with that email and it was written in a language that only the NTP-daemon would speak, and NTP-daemon wasn't getting the update requests, so disaster ensued and the system-clock was way out of whack! Point is, even automated tasks that are being done FOR you should properly be run under a separate login authorization - this is best practice for security. Nimur (talk) 21:13, 21 August 2009 (UTC)

Controlling google results

I am in desperate need of help. Someone posted my full name and other identifying information in the comments section of a video on xtube, an amateur pornography site. I have no idea why this happened. I got the site to remove my name and information, and after a lot of difficulty I got google to remove the page from a search for my name.

It is now 4 months later, and the same page suddenly started appearing on my results again, with the comment visible, even though when you actually go to the page the comment is gone. I don't know if this is a cached page or what. I don't know anything about search technology. I requested that google remove the result again but they keep denying the request. I contacted xtube but haven't gotten any response.

Anyone with a knowledge of search technology, please tell me what steps I can take or who I can contact to fix this. I can't even figure out why it is happening, so if you can tell me that I would also be grateful. Isn't it ridiculous that wikipedia is the only place I am pretty sure someone might respond to this question?

Thank you! Gohome00 (talk) 17:11, 21 August 2009 (UTC)

If by "my results" you mean "the page google returns when I search for my name", then the problem is still Google - they've not removed it from all of the places they had it, and you need to yell at them again. Unfortunately tech companies are particularly bad at responding to electronic communications, so it might be time to write to their legal department at their HQ in Mountain View, California. -- Finlay McWalter • Talk 18:06, 21 August 2009 (UTC)

I would like to not do that but I understand I might have to.... thanks!Gohome00 (talk) 20:50, 21 August 2009 (UTC)

Google can help remove personally identifiable information. There is a link to the website removal request information. Ironically, you must have a Google Account, and submit information to them, if you wish them to remove information about you. [6]. Nimur (talk) 20:20, 21 August 2009 (UTC)

I tried this 3 times. It's an automated form, and if there is some part of the request that doesn't work, all you get is a message that says "denied" with a link to a list of vague possible explanations, none of which apply to me. That's why I'm so frustrated. Gohome00 (talk) 20:50, 21 August 2009 (UTC)

Google books - copyright

Can someone help me out on this google books/copyright thing - I'm a bit confused. The impression I've got is that google has scanned (and used optical recognition to convert to 'text') books; some of which are still under copyright, and then offered them as electronic versions, but doesn't make any effort to observe any original copyright rights due to the author(s)unless they come along and claim them in which case it gives them $60. Have I got this wrong - or does something happen to the copyright when the book is scanned. eg from the Google Book Search article

publishers maintain that Google has no right to copy full text of books with copyrights and save them, in large amounts, into its own database

ok on the surface it seems a no-brainer to me that what is being described is obvious copyright violation (without a prior agreement). What's going on here? Thanks.83.100.250.79 (talk) 20:17, 21 August 2009 (UTC)

Yes, it was blatant and obvious copyright violation; the result was that Google Books stalled for nearly two years in a pitched legal battle (first in 2005), and again in a new legal fight which was recently resolved out of court (despite much continued opposition). After a re-think of the business model, Google Books now partners with advertisers, publishers, and online booksellers; they offer their service as a sort of "advertisement." Nimur (talk) 20:23, 21 August 2009 (UTC)

Any point asking "what were they thinking" (also perhaps even what happened to "do no evil" - hardly saintly anyway)

Can I ask for a second opinion (not that I don't trust your word Nimur - it's just that it seems so blatant as to be almost unbelievable) - is there no explanation for it (excluding economic boldness?) 83.100.250.79 (talk) 20:49, 21 August 2009 (UTC)

My curmudgeonly answer is that a lot of people at google really think that they are changing the world and it is their responsibility to drag everyone else along with them, even at the expense of currently accepted notions of copyright, privacy, etc. Gohome00 (talk) 20:53, 21 August 2009 (UTC)

A bit like WP:BOLD perhaps. Nobody is suggesting a legal excuse though - not even tentative ????83.100.250.79 (talk) 20:57, 21 August 2009 (UTC)

Presumably, one of the things rethought is that you will find sets of a few consecuetive pages missing from the scanned books. I have on occasion found the google books service useful, but of course the bit you want to read is always in the missing bit. Astronaut (talk) 21:37, 21 August 2009 (UTC)

If you look at the McGraw-Hill complaint found here (near the bottom) you can see some screenshots of Google Print as it existed at the time of the complaint. Public domain books were viewable in full. Copyrighted books were only viewable as a few lines surrounding the highlighted search terms (like the current fragment view), unless the publisher had explicitly authorized Google to show more. It's no different from their web search service, which also shows short excepts from each returned page with search terms in context, again without the explicit permission of the page owner in most cases. They weren't serving the full text of copyrighted works. It wasn't blatant and obvious infringement. The copyright code is very unclear regarding this sort of thing, to everyone's detriment. The result of the Authors Guild settlement was an increase in the number of full pages that are viewable, not a decrease, as far as I know. -- BenRG (talk) 00:47, 22 August 2009 (UTC)

Someone said "what happened to 'don't be evil?'" To me it sounds like Google Books did what they did staying true to the mantra. How evil would it be to withhold vast quantities of knowledge from being absolutely free to the human population? Pretty fuckin evil if you ask me. Mac Davis (talk) 01:52, 22 August 2009 (UTC)

I think you should ask authors who depend for their livelihood on their material NOT being free what they think about who is "evil" in this situation. As far as I'm concerned, unilaterally deciding that they know best IS being evil, no matter what the specifics of each situation and initiative may be. Gohome00 (talk) 17:25, 22 August 2009 (UTC)

"Don't Be Evil" is a useless slogan if evil is not well defined. Evil has a huge span of contradictory interpretations. Specifically in the case you mentioned, not everybody agrees that all information should be free - just because you and I think it should be does not make the opposite "evil." I can think of at least a few cases where information privacy might outweigh the "goodness" of information proliferation. Take a look at the unfortunate situation brought up by the previous question - this isn't a matter of copyright, but proliferating personal information, in the guise of "free expression", doesn't sound too good to me. Nimur (talk) 07:56, 22 August 2009 (UTC)

Thanks. I got the impression that they were serving up entire copyrighted books to everyone, rather than just indexing them (and displaying parts in search results). That's more understandable.83.100.250.79 (talk) 09:41, 22 August 2009 (UTC)

Resolved

Blender Fade

How can I fade objects in Blender? --81.227.67.213 (talk) 21:52, 21 August 2009 (UTC)

This was a mystery to me as well, but I experimented a bit and managed it. (I assume you mean "fade over time" rather than just making an object transparent, or transparent at one end.)

My first step was to look at the IPO Curve Editor window. On the right of this window are a list of variables you can vary over time. One of these, helpfully, is "ColA", which is to say the alpha transparency of the object's colour. To insert a keyframe, you go to the 3D view, choose a frame from the timeline and press I. The menu that pops up does not have an alpha option (or red, green or blue, for that matter). So I picked a different option, because I just wanted to get a curve of some kind into the IPO window. You should know that curves in this window can be manipulated like an object's mesh - you can press tab and select and move the vertexes around in the same way (though not in the Z dimension, since there isn't one). I therefore copied my curve to the buffer (press the icon with an arrow pointing downwards towards an orange area - apparently buffers are orange, don't ask me), deleted it (delete key), clicked on ColA on the right hand side, and pasted it. I adjusted it so that over the desired time period it went from 1 to 0, and set the interpolation to linear.

This didn't work at all. It didn't vary the object's alpha. Eventually I found out what it was varying, which was another alpha variable located on a panel called "draw" among the "object" buttons in the buttons window. Just above this is a patch of red colour: the object apparently has a secondary colour as well as a secondary alpha. The tooltip says that these are "used when faces have the ObCol mode enabled". I found that button, ObCol, among the object's material buttons, just above the sliders where you set its ordinary colour. Clicking it made the alpha fade work (and also turned it red). Hope this is what you wanted. 81.131.36.121 (talk) 01:02, 28 August 2009 (UTC)

August 22

How to really search for an exact phrase on the internet

I just searched for the phrases "Made in China (E)" and "Made in China (W)" (with quotes, as in http://www.google.com/search?q="Made+in+China+(E)"), and both Yahoo and Google just take the parenthesis out and seem to take neither the space nor the characters literal, so they'll match such strings as "made in China,e.g." or "MADE IN CHINA è un marchio di fabbrica". Is there any way to really only get the pages that contain this exact phrase? — Sebastian 01:28, 22 August 2009 (UTC)

Unfortunately, I don't think it is possible to do that (if anyone else knows a way to do so, please let us know). What you can do, though, is tell Google not to include certain phrases, such as http://www.google.com/search?q="Made+in+China+(E)" - "e.g." - "fabbrica". I did this when I was searching for info on the mathematical term "matrix" and kept getting hits for the movies. A "matrix" - "keanu" - "film" - "movie" search did a much better job for me. StuRat (talk) 13:20, 22 August 2009 (UTC)

Apparently you're only allowed _ and &. See http://www.marketingshift.com/2006/3/google-special-character-search-string.cfm 81.131.6.207 (talk) 17:32, 22 August 2009 (UTC)

Thank you, that's interesting! — Sebastian 18:51, 22 August 2009 (UTC)

The replies provide two links: http://www.google.com/apis/reference.html, which is generally interesting, but doesn't say anything about this particular issue, and http://www.google.com/support/websearch/bin/answer.py?answer=430 which is 404 now. But it's not just Google: Yahoo seems to have the same problem. — Sebastian 19:06, 22 August 2009 (UTC)

• Simply search "Made In China (E)", including speech marks. 84.92.105.93 (talk) 11:42, 24 August 2009 (UTC)

  That's what I did - it's what I meant by "with quotes" above. Yes, it should work, but it doesn't. — Sebastian 15:05, 24 August 2009 (UTC)

Download an entire YouTube channel

I want to download all of somebody's videos. There are 435. What is the most efficient way to do this? Mac Davis (talk) 01:35, 22 August 2009 (UTC)

I'm afraid you'll have to download each one seperately using a youtube video downloader. Do you use firefox? Warrior4321 04:18, 22 August 2009 (UTC)

I know enough ways to download an individual video. I was hoping there was a batch tool of some sort. Mac Davis (talk) 05:39, 22 August 2009 (UTC)

Here is a command line youtube video downloader. Here is a youtube channel's URL:

http://www.youtube.com/profile?user=BarackObamadotcom&view=videos&start=0

Here is what each video link looks like in that channel page:

href="/watch?v=R3XW5XQLnk8&feature=channel_page"

so to get the whole channel, just do something like:

#!/usr/bin/perl -w

$max_batch = ceil(435 / 20);

for $batch (0 .. $max_batch) {
  $batch_url = "http://www.youtube.com/profile?user=BarackObamadotcom&view=videos&start=$batch";
  $page = `wget -O - '$batch_url'`;
  while ($page =~ /href="(/watch?v=(\w+))&feature=channel_page"/g) {
    $vid_url = $1;
    $vid_id = $2;
    system "youtube-dl -a -o '$vid_id.avi' '$vid_url'";
  }
}

Untested! --Sean 12:49, 22 August 2009 (UTC)

Microsoft Word keyboard thing

So, what’s happened is that at work, I got a new (used) computer, but in Microsoft Word, some of the keyboard shortcuts (Control + whatever) have gotten changed around. Instead of Ctrl+c giving me the copy function it prints the character “ç” for some reason. It’s the same for Ctrl+a, instead of selecting everything, it prints “à,” and Ctrl+ gives “î” instead of italics. There are probably some other ones. It’s really annoying. Anyway, how can I stop this and bring everything back to normal? I’ve looked in the help file and online, but apparently I haven’t typed in the right words or something. Anyway, any help you have will be greatly appreciated. Thanks. 169.231.32.17 (talk) 08:07, 22 August 2009 (UTC)

It sounds like your Ctrl key now has the function of an AltGr key. Have you installed the computer from scratch, or did you take someone else's installation? If the latter, then maybe that person messed around with the keyboard layout. There are programs, such as Microsoft Keyboard Layout Creator and Wyrdplay, with which you can change the individual key settings. Maybe you can reset it by going into Control Panel -> Regional and Language Options -> Languages tab -> Details -> under "Installed services", select "English" -> click Add button -> check "Keyboard layout/IME" -> in the dropdown, select another layout (presumably one of the "United Kingdom" or "United States" settings, depending on your preference). — Sebastian 19:23, 22 August 2009 (UTC)

Oh, I overlooked that you wrote "Microsoft Word". Do the keys behave as expected in other programs? In that case, it seems as if the settings in Word have been changed. Go to Tools -> Customize -> Keyboard button -> Reset All. (Before you reset all, it may be wise to check if the keys are really reassigned in word by testing them. Do that as follows: Select the box under "Press new shortcut key" and check what it says below after "currently assigned to". If that's the correct function, then the key has not been reassigned in Word. — Sebastian 19:29, 22 August 2009 (UTC)

I'm pretty sure it's the second one, but in either cse, I now know what to do. Thanks so much. 169.231.32.17 (talk) 19:35, 22 August 2009 (UTC)

Adobe's code signing cert revoked?

Hi, I'm trying to install Flash on XP. The installer downloaded wouldn't run, saying "You must unblock this publisher". Digging further, I found that the code signing cert issued to Adobe Systems Incorporated serial ‎76 57 f9 cb ca c1 ea 95 04 83 8e 3e d9 35 5d 2d is "revoked by its certification authority". Anyone know why? Should I just remove the revocation and install it anyway? 121.72.171.75 (talk) 10:30, 22 August 2009 (UTC)

FWIW, I can't reproduce this under Windows 7. The installer runs fine. — Matt Eason ^{(Talk &#149; Contribs)} 01:45, 23 August 2009 (UTC)

OK this is weird, Youtube works fine now, no need to reinstall Flash. Thanks. 121.72.171.75 (talk) 09:14, 23 August 2009 (UTC)

How to reinstall Windows XP - where can I get CDs?

I have MS Windows XP which I have a license for. I have no install CDs - either I lost them or I suspect I never had any. How can I get them - will MS give them to me? Thanks. —Preceding unsigned comment added by 62.49.27.114 (talk) 11:31, 22 August 2009 (UTC)

Contact whoever you bought the computer from (assuming it came with XP?) - They may be able to sell you a "media kit" for a small fee. ZX81 ^talk 11:53, 22 August 2009 (UTC)

Check first whether there is a recovery partition. 121.72.171.75 (talk) 12:16, 22 August 2009 (UTC)

Download them —Preceding unsigned comment added by 82.43.89.136 (talk) 05:34, 23 August 2009 (UTC)

I removed a direct link to a probable copyright violation above which is against policy Nil Einne (talk) 18:11, 23 August 2009 (UTC)

I linked to a search engine, not any copyright works directly. My link was no more of a copyright violation than linking to a google search string.

That's a highly inaccurate description of what you did and your link was most definitely a link to a probable copyright violation. In any case, this is clearly OT here so I won't discuss it anymore here Nil Einne (talk) 19:05, 23 August 2009 (UTC)

My link was to a page on mininova.org, a simple html page with text and a few images. There is zero copyright work in that page. —Preceding unsigned comment added by 82.43.89.136 (talk) 19:19, 23 August 2009 (UTC)

Thanks, but we're not up for any sort of pointer to a copyright violation. --Tagishsimon (talk) 20:09, 23 August 2009 (UTC)

[7] may be of use Nil Einne (talk) 20:50, 23 August 2009 (UTC)

To clarify the "recovery partition" mention by 121 above — HP, for example, does this; the hard disk is partitioned so C: is most of the drive, and D: is the "recovery partition". You are supposed to get 3 DVD+R discs when you open up your computer, and run a utility that ships on the HP's hard disk which will use the data on the D: drive to create boot discs you can use to start from scratch, erasing everything on the hard disk and returning it to the way it was when you first opened the box. (They make you burn these discs rather than ship the discs in the box, because, like all computer manufacturers, HP is trying to shave every cent off of the cost of the computer.) I think you can boot from the D: drive, too, though I'm unsure whether HP's recovery partition lets you. Anyway, look to see if your computer has a similar D: (or other letter) drive that looks like it might be a recovery partition, and you may be able to boot from it or otherwise recover the C: drive with it — check the website of your computer manufacturer. Tempshill (talk) 05:27, 24 August 2009 (UTC)

Testing a web based software Vs testing a conventional software

Its not about comparing two types of softwares that do the same. It is about differences in testing methodologies. Can you please say the differences in testing a web based software (say a pixlr) and its software counterpart (say gimp)?. —Preceding unsigned comment added by 131.220.46.25 (talk) 13:06, 22 August 2009 (UTC)

With any web-based software, I would expect the performance to vary dramatically based on the current connection speed. Therefore, you'd need to test to see how it handles that. For example, Netflix streaming videos dynamically adjust the image quality based on the current connection speed. Software that doesn't do that may become unusable if the speed drops dramatically, as it often does. Netflix also has an example of how not to do things, on their queue on their website. When you select the widget to move a movie to the top of the queue, it appears to move it up one position in the queue, refresh the page, then move it up another position, refresh the page, etc., until it gets to the top. This type of inefficient programming may work fine on a dedicated computer, but not when dealing with web connections of suspect speed. Instead, the obvious solution is to move the movie to the top of the queue and only refresh the page once, instead of up to 500 times.

So, any web-based testing should be run with both high-speed and low-speed connections. I'd even test on dial-up, to see what happens. StuRat (talk) 22:43, 22 August 2009 (UTC)

I'd add that testing should not only be high-bandwidth vs. low-bandwidth, but also high-latency vs. low-latency. Another awful area of testing is that you do not control what browser your users are using. There will be bugs viewing the web-based software in Internet Explorer 6 that do not exist when using Mozilla Firefox 2, and probably vice versa. Tempshill (talk) 03:42, 23 August 2009 (UTC)

Not just bugs, but varying levels of implementation of javascript and the document object model amongst others.

A related question came up a few moons ago about how to find what language a user is using within a browser - the actual implementation of this is more complex that might be thought see [8] - in this case the way the navigator. object works depends on what browser is being used - I imagine there are many more (I'd call this a bug). Assuming you are aware of these issues it should be a design problem rather than testing..83.100.250.79 (talk) 18:44, 23 August 2009 (UTC)

glDeleteTextures

I've been doing some OpenGL programming (in C, no garbage collection). Will I be leaking graphics card texture memory if I don't call this function at the end of my program? The examples I've been working from don't use it, and the GL redbook only mentions it as useful for freeing up memory to put more textures in. 81.131.6.207 (talk) 17:10, 22 August 2009 (UTC)

You won't be leaking memory. The gpu driver will get informed when your program terminates and free (if it's not buggy) all resources allocated by you. --194.197.235.63 (talk) 18:10, 22 August 2009 (UTC)

Excellent! Thank you. 81.131.6.207 (talk) 18:36, 22 August 2009 (UTC)

chess script programming

is there any way to change the script for the chess game that comes with apple computers? I want to tinker a bit but can't find it's programming... Thanks for any help 81.34.109.174 (talk) 17:41, 22 August 2009 (UTC)

It's a compiled program, not a script. You can get the source code here. --Sean 18:51, 22 August 2009 (UTC)

Specifically, here — Matt Eason ^{(Talk &#149; Contribs)} 01:43, 23 August 2009 (UTC)

August 23

chroot and graphical apps: is it possible?

is it possible to set-up a chroot and use graphical apps? I don't want them in a xnest window or similar, I want them to be displayed on my normal desktop, like all other apps. Is this possible? How can I do it? (I already have the chroot prepared) - SF007 - 05:07, 23 August 2009 (UTC)

Yes; but I think you might be confused about what chroot does. Which graphical application do you plan to use? I think anything which uses any dynamically linked libraries is going to complain if you chroot it and deny access to your library paths... are you writing the graphical applications yourself and statically linking them? Nimur (talk) 06:57, 23 August 2009 (UTC)

You could always copy the libraries your app needs into the chroot. The debian debootstrap package might be useful. --194.197.235.54 (talk) 11:13, 23 August 2009 (UTC)

Mediawiki Error - Still

Not writing this againRgoodermote  06:20, 23 August 2009 (UTC)

Chances are, everyone who looked at your question earlier was unable to answer it. Reposting probably won't help. If you can rephrase or elaborate on what the problem is, we might be able to help; but just reposting (especially when the original post is still on the desk) is not going to get you any more answers. Nimur (talk) 06:54, 23 August 2009 (UTC)

Well that is as elaborate as I can actually make it, I can tell you that it seems to have something to do with my version of PHP. As I never noticed it before till today that the PHP number was 5.1.37 not 5.1.33 and some Google searching turned up a lot of people complaining..but of course getting no answers..about this problem. When I updated my version of PHP is beyond me. I also got this little doozy recently "Warning: Parameter 1 to ConfirmEditHooks::confirmEditMerged() expected to be a reference, value given in ***\w\includes\Hooks.php on line 132". Second, I find it unlikely that there is not one single person on Wikipedia who can't answer this question. Rgoodermote  07:20, 23 August 2009 (UTC)

The obvious thing to try is to go to an earlier version of PHP, hopefully without the bug. StuRat (talk) 08:23, 23 August 2009 (UTC)

The Reference Desk is only read by a tiny fraction of Wikipedia users. I promise we're not holding out on you; nobody here seems to know the answer. Perhaps you should contact the developers of the software? --Sean 14:08, 23 August 2009 (UTC)

It sounds like a legitimate software bug (with MediaWiki); try contacting the developers. The message means that a wrong variable type is being passed to a function, which is the sort of thing they are probably interested in knowing about. --98.217.14.211 (talk) 16:45, 23 August 2009 (UTC)

(undent) Thank you to the above, as for downgrading PHP, I tried that, however it's nigh impossible, it for some reason will render Apache unstartable and the error does appear to be related to PHP, however it is most likely related to a variable that was probably removed from the latest PHP release that the software relied on..so yeah a bug. I looked around and it would appear that I am not the only one who is having this issue. Rgoodermote  22:59, 23 August 2009 (UTC)

I filed a bugzilla report. So I'd say this is resolved if anyone else wants to comment. Rgoodermote  23:13, 23 August 2009 (UTC)

To me, this does not look remotely like a bug with PHP. This looks like your extension is not for the version of MediaWiki that you are running. Each extension will state which version of MediaWiki it was designed for (and some work with multiple versions). -- kainaw™ 23:15, 23 August 2009 (UTC)

It ran fine before updating PHP, I used 1.16WMF for some time before and used only the software bundled with it. This only happened when setting up a wiki on the latest version of Xampp/Lampp (those two continually get misspelled by me by the way) which had the latest version of Apache, PHP and MYSQL. On earlier version of the Xampp/Lampp software the mediawiki software worked like a charm. Rgoodermote  00:11, 24 August 2009 (UTC)

I want to clarify that when I said it looked like a bug, it is with the software (e.g. the extension or MediaWiki or whatever), not PHP. --98.217.14.211 (talk) 02:19, 24 August 2009 (UTC)

To those who guessed software bug with Mediawiki, you would be correct. Rgoodermote  03:20, 24 August 2009 (UTC)

"This was fixed yesterday." Love it. Tempshill (talk) 05:30, 24 August 2009 (UTC)

Resolved

Practical measures to preserve privacy and security when computer is stolen

What can I do to preserve my privacy on the assumption that my computer will be stolen one day? I dont just mean keeping credit card details safe, but keeping correspondence encoded or otherwise private? Log-in and other passwords too. (A version of OpenOffice that works with encoded word-processing files would be a good idea.) Something good enough for the average computer -burglar or -fence not to bother with decoding it rather than just deleting it. This is a seperate issue from backing up files. 78.149.186.253 (talk) 13:14, 23 August 2009 (UTC)

The easiest way would be to just encrypt the whole hard-drive or at least the user directory. Most operating systems have ways to do this built into them (e.g. FileVault for Macs). If you want to encrypt the whole thing, TrueCrypt can do this. Doing it on a file-by-file basis is not terribly practical—that's a lot of passwords to type in, and makes it quite difficult to send you files to others, and there are cryptologic problems with encrypting lots of small files. --98.217.14.211 (talk) 13:42, 23 August 2009 (UTC)

I partially agree with 98. Although I've never done this, TrueCrypt can encrypt the entire hard disk, so it will be unusable to anyone who does not know (and can't guess) the password. BitLocker is Microsoft's full-disk encryption system, which comes with some versions of Windows Vista and Windows 7. Alternatively, you could use TrueCrypt to create a single "container" file on your hard disk that is encrypted, and store all your sensitive data in that container file. But it sounds like you want a little more certainty than that in the case of Outlook's .pst files being stored somewhere else, maybe temporary files on the hard disk will have sensitive data — whole-disk encryption avoids all those problems. Tempshill (talk) 17:26, 23 August 2009 (UTC)

Windows Movie Maker

Is it possible to download windows moviemaker to XP without downloading service packs? —Preceding unsigned comment added by 81.197.87.181 (talk) 13:54, 23 August 2009 (UTC)

Windows Live Movie Maker requires at least Windows XP with Service Pack 2 to run, so it's either install the service pack or don't install Movie Maker. (Is there any particular reason you don't want to install a service pack? I can't think of any.) Xenon54 (talk) 17:58, 23 August 2009 (UTC)

Well I can't imagine installing SP2 on a fresh Windows XP over dialup is a fun experience, particularly if you pay by the minute. For that matter installing over a GPRS connection. However the IP looks up to a Finnish ADSL connection which doesn't exactly speak 'slow connection' Nil Einne (talk) 18:09, 23 August 2009 (UTC)

A LOT of things require at least SP2 nowadays; in a developed country like Finland there is very little reason to use vanilla XP (not to mention the security vulnerabilities). --antilived^{T | C | G} 09:50, 24 August 2009 (UTC)

Java: loading only the objects you need

Hello! I'm working on a Java program that randomly creates simple sentences one-at-a-time from a bank of Word objects. Each word object will contain significant fields such as a string representation of the word, gender, part of speech, etc. The only way I know how to do something like this is declaring and constructing every Word into memory:

Word word1 = new Word("dog", Gender.MALE_AND_FEMALE, PartOfSpeech.NOUN);
Word word2 = new Word("man", Gender.MALE, PartOfSpeech.NOUN);
Word word3 = new Word("she", Gender.FEMALE, PartOfSpeech.PRONOUN);
//...

But each randomly generated sentence will only contain a few Words, and declaring all the Words the program can draw from uses memory way too inefficiently. I need a way to have the program load only the words needed for a sentence then dispose them and get new ones for another sentence. So, my question is, what is the most efficient way of accomplishing this? I was thinking about creating a file full of all the Words (or separate files full of related words, like noun file and verb file), and the program just randomly streams in all the objects it needs for each sentence, but I'm not sure how to do this or if this is the best way. Thank you for any advice!--el Aprel (^facta-_facienda) 21:28, 23 August 2009 (UTC)

If each instance of Word only contains a String and a couple of enums, that's really not using very much memory, so even tens of thousands of them won't take up that much storage. It sounds like you should have an array of Word objects (whether initialised from a file or from a static initialiser is up to you). But if you really are very hard-up for memory, and are sure that you only want a few Word objects in memory at once, then you'd need to load them from some randomly-accessible store (accessed by something like java.io.RandomAccessFile.seek) - but doing that will take some kind of index or a standard layout (which means it's a bit of work organising things). -- Finlay McWalter • Talk 21:39, 23 August 2009 (UTC)

What you have is a database, in the generic sense. There are many ways to store data in files for efficient retrieval. For your purposes a sorted CSV file may be suitable:

"dog","MALE_AND_FEMALE","NOUN"
"she","FEMALE","PRONOUN"

etc. More sophisticated requirements might make using a relational database sensible. For anything beyond a toy program or school assignment keeping the data in the program -- and recompiling when it changes -- is going to be a pain. --Sean 21:47, 23 August 2009 (UTC)

Help getting rid of horrible trojan

Hello. I few weeks ago I posted here about a virus horribly infecting my computer—"System Security 4.52". I got good advice to download Malwarebytes, which I did. It was successful in removing part of the virus but not all of it. Specifically, I was able to download it in safe mode with networking, and then ran it, and once downloaded, ran it in safe mode, where it found some of the files, which I deleted. Then I restarted and ran it again (now that I was able to open up the program, which the virus theretofore blocked) and it found more of the virus which I deleted. And everything looked fine—for a time, until the virus came back! I went through the same procedure again, and it came back again, and I've just done it for a third time in order to get online to write this post. Obviously, the virus is leaving something on my computer that is downloading itself back to my computer. I am running Avira Antivirus. Windows XP. Dell Dimension 8400. Thanks in advance.--141.155.22.185 (talk) 23:21, 23 August 2009 (UTC)

If I was you I would backup all my important data, reinstall OS, install antivirus, and scan the backupped data for viruses before starting to use it again, or better yet just dump it and be safe for sure. --194.197.235.54 (talk) 23:53, 23 August 2009 (UTC)

I don't know how to do that. If I could I would do a system restore but when I try it just doesn't work.--70.19.34.166 (talk) 00:21, 24 August 2009 (UTC)

Reinstalling windows should be an easy solution - did the computer come with an XP disc (CD)?83.100.250.79 (talk) 00:37, 24 August 2009 (UTC)

I agree with 194, I'd back up everything, format, reinstall, and start from scratch. You'll need your Windows disc. Tempshill (talk) 02:59, 24 August 2009 (UTC)

I heartily recommend AVG Free, Superantispyware Free and ComboFix.[9] ---— Gadget850 (Ed) ^talk 03:15, 24 August 2009 (UTC)

August 24

all website links

Resolved

I need to way to scan an entire website and list the url of every html page, image, and file in a plain text —Preceding unsigned comment added by 82.43.89.136 (talk) 08:13, 24 August 2009 (UTC)

• Sorry but the only way to do this is to manually visit and get the url for every page

Alex (talk) 11:54, 24 August 2009 (UTC)

bullshit. sorry but web crawlers do exactly what I'm asking, they just download files instead of generate a list of links. I'm looking for something similar to a web crawler, that will scan the site and list every link, file and image. —Preceding unsigned comment added by 82.43.89.136 (talk) 12:52, 24 August 2009 (UTC)

I imagine greasemonkey would allow you to do this, though you'd have to write a script to make it so. --Tagishsimon (talk) 12:55, 24 August 2009 (UTC)

I have a greasemonkey script that can extract links from a single page, but that's not what I need. I need a program to scan an entire website, possibly hundreds of pages, and list every .html .jpg .exe etc etc link it finds. —Preceding unsigned comment added by 82.43.89.136 (talk) 13:08, 24 August 2009 (UTC)

Use wget to get all .htm or .html files (with its "recursive" parameter), then process the files with a Perl script using regular expressions to get the names on all the links? (I don't know the details of this, but it should be possible to learn with some effort) Jørgen (talk) 14:06, 24 August 2009 (UTC)

:( I was hoping for an easy way. I found this program called URL Extractor which does exactly what I want but it's limited on a free trial. I've searched for free open source alternatives but can't find anything. Ah well, thanks for trying :) —Preceding unsigned comment added by 82.43.89.136 (talk) 14:30, 24 August 2009 (UTC)

Try Xenu - it has some save/report options that probably do what you want. Unilynx (talk) 21:26, 24 August 2009 (UTC)

holy shit that's perfect, THANK YOU!

With wget, you can just run wget -m --delete-after -nv http://yoursite.com and it'll do pretty much exactly what you want, although it'll download every file on the website, so it can take a lot of bandwidth/time. If you use this on a site that you don't own, it would be considerate to use a wait interval, like -w 10. This will take a lot more time, but cause less load on the server. Also, keep in mind that using recursion won't show you files which aren't connected to your starting point through some path of links. But other than that, it's an easy solution. Indeterminate (talk) 22:40, 24 August 2009 (UTC)

You can tweak that command in various to make it faster and friendlier, like excluding everything but HTML files and so on. There are many reasons this won't get all links though, as web sites are very dynamic these days. --Sean 23:58, 24 August 2009 (UTC)

Using Nokia AD54 remote control as an extension cord

I'm trying to use the Nokia AD54 remote control as an extension cord for my earphones on my laptop since the cords on my earphones are extremely short. It works well on my Nokia phone and on my stereo but on my laptop (a Dell Vostro) when fully pushed in gives something like a poorly designed vocal removal effect, which I suspect is because it's sending signal L-R to both channels of my earphones. If I pull it out a bit I get left channel on both earphones. The connector on the remote is a standard 3.5mm TRS connector with an extra ring above the right channel. Does anyone know why does it not work on my laptop while it works on my stereo and desktop? Is there anything I can do to fix it? --antilived^{T | C | G} 11:13, 24 August 2009 (UTC)

problem in Excel: left and right buttons navigate bar instead of going from one cell to another

Hello there, everyone:

I have a problem with Excel which is small but considerably annoying. I rely on using the left and right buttons to go from one Cell to another, as it makes putting in a bunch of data much easier than constantly clicking. Suddenly, it stopped doing this and now it only goes moves the navigation bar without going from one cell to another - does anyone know how to fix it?

All the best —Preceding unsigned comment added by 81.202.202.14 (talk) 12:50, 24 August 2009 (UTC)

This is usually because you have your Scroll Lock on. ny156uk (talk) 13:27, 24 August 2009 (UTC)

Anyone an expert on DOS game history?

Please see Wikipedia:Reference_desk/Entertainment#Game 83.100.250.79 (talk) 14:38, 24 August 2009 (UTC)

Unblocking a downloaded file in Windows Vista

I have downloaded an executable file from the Internet, and I am positive that it is not malicious. However, Windows Vista has blocked it, so I have to confirm the execution of the program, everytime I try to run it. This is very annoying. And worse yet: In the file properties dialog box, there is a "Unblock" button, but it does not work! (Apparently this is a bug in Windows - even if Microsoft for some reason really do not want me to be able to unblock the application, the button should not be enabled if it has no effect. I have SP2.) I have tried to run "explorer.exe" as administrator, and opened the file properties dialog from there, but that did not work either. How to unblock the file? --Andreas Rejbrand (talk) 18:42, 24 August 2009 (UTC)

Apparently the zone information about where the executable came from is kept in an alternate data stream associated with the file. One way to supposedly clear up the problem is to download this command-line program. If you put streams.exe in the same folder as your executable, then open a command prompt, cd to that folder and type "streams -d (yourexecutablefilename).exe", it'll delete the associated data streams. Hopefully that should clear it up. If you want to disable the feature altogether, try option 3 on this page to disable it through local policy. Indeterminate (talk) 22:13, 24 August 2009 (UTC)

He can also do it an easy way and right click go to properties and there should be an option to unlock it. Rgoodermote  06:54, 25 August 2009 (UTC)

If you had read my original post three paragraphs above, you would have noticed that this was the first thing I tried, but it didn't work! :) --Andreas Rejbrand (talk) 11:52, 25 August 2009 (UTC)

Thank you very much, Indeterminate! It really worked! --Andreas Rejbrand (talk) 11:56, 25 August 2009 (UTC)

Resolved

Why does the fan stay on after switching off?

I have read that the leading contributor to eventual failutre of electronic components is the constant warming up and cooling down, and that it is better for the components to warm up slowly and cool down slowly. Why then, would a fan continue turning (both my laptop and PC PSU do this) after the power goes off? Surely this is unecessary at best and at worst, damaging by cooling component down more quickly that would otherwise be the case? ----Seans Potato Business 18:54, 24 August 2009 (UTC)

If you have a hot object, that's being continually kept cool-ish with a fan, and you turn off the power to both it and the fan at once, it will be at the same temperature (for a while) but without the fan cooling it will stew in its own heat. Keeping the fan on for a while after lets its temperature coast down to ambient at a more gradual pace. Remember that you're not really "cooling" something with a fan, just controlling the extent to which it heats its environment. -- Finlay McWalter • Talk 19:47, 24 August 2009 (UTC)

Also, while thermal-cycling is probably a leading cause of failure for certain components, (e.g. wirebonds with different thermal expansion coefficients); other components (like semiconductors) are probably more sensitive to number-of-hours-exposed-at-temperature. Migration of dopant is proportional to number of hours endured at high-temperature. Failure analysis is a tough problem; letting the fan run seems like an "engineering approximation" to the optimal thermal profile, given the constraint that it's hard to really estimate the likely cause of failure, and even harder to actually control the temperature in an ideal way. Nimur (talk) 21:23, 24 August 2009 (UTC)

FWIW integrated circuits don't fail because of doapnt migration - much higher temperatures are needed for that that you will ever get running hot (typically 800 to 1200 degrees celcius). They fail for a variety of other reasons, but one classic failure mode was "electromigration", where aluminium atoms are pushed along by electrons and we end up with voids in the conductor tracks. That, like most other failure modes, is temperature sensitive. Of course, if you get the chip hot enough, the aluminium will just melt :-) --Phil Holmes (talk) 08:31, 25 August 2009 (UTC)

I have never seen a computer PSU keep the fan running after turning the power off. Slide projectors do let you leave the fan running after the lamp is turned off, and a myth evolved that cooling the bulb down faster (by running the fan) makes it last longer. The real reason for that feature is that if a bulb burns out, you want to cool it off quickly so you can change it without burning your fingers, minimizing the length of interruption to your slide show. 70.90.174.101 (talk) 07:52, 25 August 2009 (UTC)

I own a "Be Quiet 1200W Dark Power Pro Modular" PSU and it does this by design. There are 4 special ports designed specifically for fans to be connected to them and they keep those 4 fans spinning for 2 minutes after the machine has powered down. I don't have the manual to hand, but the reason was literally something like because it keeps cooling the components down rather than just leaving them hot like a normal PSU would. ZX81 ^talk 12:30, 25 August 2009 (UTC)

August 25

Zipped folders

In Windows XP... is the compression algorithm used by zipped folders lossy or lossless? --72.197.202.36 (talk) 00:51, 25 August 2009 (UTC)

Lossless. -- Finlay McWalter • Talk 00:55, 25 August 2009 (UTC)

Lossy file compression wouldn't work that well. Lossy compression is generally used for things that have analog analogues (hmm)—images, video, sound. The human brain patches together the lost bits or ignores them. For things that are wholly digital—text, for example—lossy compression would totally corrupt it and not be recoverable. I'm willing to wager that NO practical folder compression algorithms are lossy. --68.50.54.144 (talk) 02:16, 25 August 2009 (UTC)

Fair point... Thanks! --72.197.202.36 (talk) 21:39, 25 August 2009 (UTC)

Well spoken, 68... sorry to nitpick (but this is the refdesk!) "Wholly-digital" is probably a poor choice of words, since lossy compression is also "wholly digital" (and ascii text does have an analog equivalent). I think your meaning comes across, though. Lossy compression works better on multimedia data like images, movies, and audio. Our lossy compression article does talk about applications to text, and includes a fairly complicated published algorithm. The simplest one I can think of is simple vowel removal (lvng mst txt stll rdabl to mny rdrs). In general, though, this is not applied by standard file compression. The original poster can be assumed to be describing the pkzip format, which uses a lossless LZ77/Huffman coding algorithm; or gzip (which uses the same lossless technique). But, in general, a folder could be serialized and compressed by any algorithm (with potentially catastrophic results and unrecoverable files). There's no reason JPEG couldn't be applied to an arbitrary input file (we could pretend the bits represented a grayscale image, for example; zero-padding and a suitable spoofed header might be needed to stuff the file in to a standard tool). The result might be fun! Nimur (talk) 03:12, 25 August 2009 (UTC)

Wiki markup

This may be a dumb question, seeing that I barely understand even one other question posted on this desk -- I notice wacky things in Wikipedia that I never knew could exist, in terms of: formatting mathematical equations, colored bands and bars and boxes, large font-almost cartoonish quotation marks, and lots of things I can't remember, but basically, things that are way more sophisticated that just plain text. Is all of it programmed in to be able to work, or do you just play with the markup and things happen (that's sort of the dumb part :) If it is all programmed in, how does everyone know how to do it? Is it listed somewhere? The way I do it is I have to wait until I see something crazy and then I click "edit this page" and try to figure out the HTML (I think that's what it's called) -- but obviously, that's not the way to do it properly, or else the first time never would have happened. DRosenbach ^{(Talk | Contribs)} 02:05, 25 August 2009 (UTC)

Some of it is in HTML, some of it is in CSS, and some of it (the equations) are in a specialized language called TeX. People who do science or math know TeX because it is basically required if you do anything with equations these days in an academic setting (even science papers that don't have equation are usually written in TeX). TeX is powerful but not user-friendly—it's one of those, "once you know it, you know it and can use it a lot, but if you don't know it, it might as well be Chinese" sort of things. Wikipedia has special TeX interpreters that render the code as graphics—it's a plug-in or something like that.

As for HTML and CSS, they are just standard web markup. If you do any web programming you know them. Wikipedia doesn't do anything special with them, other than not filter them out. --68.50.54.144 (talk) 02:19, 25 August 2009 (UTC)

How did we learn them? Some of us have been here a while; you pick up on details and learn how to navigate the (somewhat disorganized and scattered) help pages. First, you might want to read Wikipedia:Template messages to learn about the basic syntax of templates. Next, you might want to read Help:Displaying a formula, Template:Cquote, and Wikipedia:COLOR - since you specifically asked about those things. Then, to broaden your understanding overall about how the wiki works, you can start learning about wikisyntax in general. Technically, the correct term is wiki markup or wikitext, (not HTML). One of the primary roles of the MediaWiki software (which runs on the Wikipedia servers) is to convert wikitext into renderable HTML and CSS (which your browser then uses to actually draw the fonts and images to your screen). Wikipedia / MediaWiki does this with server-side scripting (in php). Technically, you can manually add a lot of HTML into the wikitext area, but this is frowned upon for a variety of reasons. You can read Help:HTML in wikitext for details. Finally, you can read the Help:Contents for a general overview. Some subtle things, like the difference between WP:Project namespace and WP:Article namespace never really get "explained" to newcomers - you either pick up on the detail, or ignore it. If you install your own copy of MediaWiki on your own server, you'll have the opportunity to muck around with more of the under-the-hood implementation details; that insight will help you understand the interplay of all the different components of the wiki. Nimur (talk) 03:20, 25 August 2009 (UTC)

IGGP site missing!

Hello, I am the chair of the Steering Committee of the International Grape Genome Program (http://www.vitaceae.org/index.php/International_Grape_Genome_Program). This page has been operational recently (at least a couple of weeks ago). I checked the page today and it won't open. I don't know what to do. Has it been deleted? Has the link been damaged? Any advice on what I must do would be most helpful.76.193.49.119 (talk) 04:04, 25 August 2009 (UTC)

I can't even access the main page, let alone the subpage you linked. (Though, I can ping the machine, so it's alive). It seems like the web-server has been disabled or is no longer reachable through that alias; possibly, some new firewall is responsible. Your best bet is to contact your web administrator or IT specialist. Tell them the web server at 169.237.195.13, or its network, needs maintenance. If it is managed (as I suspect) by UC Davis, your IT guys can be found here or by phone (530-754-HELP (4357)). Nimur (talk) 06:38, 25 August 2009 (UTC)

CD copyright information

Is copyright information on CDs, DVDs, and BluRay discs, regulated in a way, so that the information may be found, in the same way, in the same format, so that programs may check any copyright info without problems?

For example, Copyright (C), TradeMark (TM), and RightsRestricted (RR) symbols are regulated, so they may always be found in the bottom right corner of the image, name, logo, etc. —Preceding unsigned comment added by HitmanNumber86 (talk • contribs) 05:24, 25 August 2009 (UTC)

Nope. You can safely assume that everything recent is copyrighted. If the author has granted you particular rights (such as under a Creative Commons license), they'll make that obvious by including the license or a reference to it. And no, those symbols are not "regulated" in the manner you suggest. --FOo (talk) 08:08, 25 August 2009 (UTC)

Driver update

Hello there, recently I have upgraded my system. I found a driver update link in ATI catalyst control center (My graphics card is XFX 4890 1 GB). After clicking on "update driver" link, this page appeared and showed that driver update for XP, Vista and windows 7 (both 32 and 64 bit) are available. I already have CD for my graphics card provided by manufacturer. Both XP and Vista showed that G. Card driver is up to date. Should I stick with CD or go for up date to that link? (though 4890 1 GB released on April 2, 2009. It's not so backdated)if I download and install that driver update should I uninstall my previous one, though they are same driver software?

One more thing, if you go to that page you'll see three box. First One is for Operating system second one is for product family and third one is for product series. There I found that two series are available for updating. One is Redeaon 4890 series and another one is Radeon 4800 series. I checked both them and they showed same driver software. If they are same then why they are representing two separate series? Which series I should pick up? Thank you--119.30.36.45 (talk) 08:31, 25 August 2009 (UTC)

Language changes in Microsoft Word (resolved)

Whenever I type the following in Microsoft Word, the set language changes to Russian and the characters are replaced with what I assume are the ones in the same keyboard position on a Russian keyboard:

5. R = 5.5 cm; Q = 20.5 nC; R_in = 10.5 cm

changes into

5ю К = 5ю5 сьж Й = 20ю5 тСж К_шт = 10ю5 сь

Why does it do this and how do I stop it? --superioridad ^(discusión) 09:16, 25 August 2009 (UTC)

Never mind, I figured it out. Incidentally, the 'detect language automatically' feature is incredibly annoying. --superioridad ^(discusión) 09:21, 25 August 2009 (UTC)

Project management software

Is anyone able to identify the program that has been used to create this image (before I removed most of the text in an image editor)? Could anyone recommend open-source software that runs on Windows, suitable for creating such graphs, and for project management in general (single-user programs are ok)? Thanks, --NorwegianBlue ^talk 09:32, 25 August 2009 (UTC)

It looks somewhat like a Gantt chart. If so, there are some OS options on comparison of project management software. --Sean 13:08, 25 August 2009 (UTC)

Definitely. I've been looking through the list and its quite a mixed bag. I realize that my question should be more focused.

1. I need to insert tasks on a time axis, with their estimated duration
2. I need to insert deadlines/milestones
3. I need to put the tasks into different categories, that are reflected in the graphical output (e.g. with different colors).
4. I want reasonably visually pleasing output (I liked the output in the image I linked to).
5. Ability to indicate the interdependencies of tasks would be nice, but is not a must.

I do not need

• document management or version control
• issue tracking
• allocation of manpower.

Although I asked for recommendations for windows-based programs, a php+mysql web-based program would also be of interest. I installed Planner now on a linux machine, to try it out (it appears to have a Windows version too). Unfortunately, it does not satisfy my requirements number 3 and 4. --NorwegianBlue ^talk 14:32, 25 August 2009 (UTC)

My experience is with Microsoft Project, but pretty much any Project management software should be able to do what you want. Unfortunately, the list suggests to me that not all packages are equal. From the Open Source products, I would suggest taking a look at Project.net, eGroupWare and GanttProject. Project.net requires Oracle (definitely not open source and not free either), eGroupWare has web interface and requires PHP and a database like MySQL, and GanttProject could be limited in what you can do (but it does create Gantt charts). One hint might be to consider resource management as a means to separate the tasks into categories. Astronaut (talk) 22:06, 25 August 2009 (UTC)

Game not compatible with vista?

Hi I just bought age of mythology and the titans expansion pack from ebay and at the time I didn't realise that the items advert said the game not compatible with windows vista. I was wondering why this is. If it is compatible with XP why not with vista? RichYPE (talk) 09:47, 25 August 2009 (UTC)

Can you not tell vista to run it in XP mode? I vaguely recall this is an option ... indeed, after right-clicking on an exe, one can select properties, compatibility. Not sure if it'll work for you but... --Tagishsimon (talk) 13:14, 25 August 2009 (UTC)

[Obligatory Vista-hating message] 67.243.4.208 (talk) 16:20, 25 August 2009 (UTC)

hmm I am in a bit of a dilemma now... The game is new and still in its packaging. If I open it and try and run it in XP mode and it doesn't work I can't return it. Someone please help! Thanks RichYPE (talk) 21:14, 25 August 2009 (UTC)

Googling "age of mythology vista" seems to return a lot of people having problems with it so unfortunately I'm afraid there probably isn't going to be a yes/no answer, but it doesn't look good. It might work, it might not. As you know it didnt' say it supports Vista, but this isn't just because the game was released before Vista's launch, it's officially not supported even with patches. Sorry I haven't been able to be of much help. ZX81 ^talk 21:41, 25 August 2009 (UTC)

Current in mac mini

I have a mac mini that seems to be discharging a constant current through it... It gets stronger at the back to the point of not being able to touch it... It's giving off at least a few volts of electricity but definitely more than that... If anyone knows anything about this some advice would be muchly appreciated... Thanks 81.35.161.99 (talk) 10:00, 25 August 2009 (UTC)

Well, I know you should unplug that computer right now and have an actual technician look at it, since clearly you aren't one yourself. -- Captain Disdain (talk) 11:02, 25 August 2009 (UTC)

IMAP: Loading all messages simultaneously

I am using a slow internet connection, which causes Thunderbird to take a long time to download each message. It loads each message individually: I click on a message, it loads, and appears in the viewing panel below. On hitting the down arrow, it may take 10sec to load the next one.

Is there a way in which Thunderbird can download them altogether, so I can do something else while they all load? My name is anetta (talk) 10:42, 25 August 2009 (UTC)

Rightclick the account (in the left-hand bar), hit properties, go to the "offline and disc space" section for that account, and hit the "make the messages in my inbox available when I am working offline". It should then download all the messages. -- Finlay McWalter • Talk 12:17, 25 August 2009 (UTC)

DTMF

Why the telephone has to sound the DTMF coding at every telephone call?--Mikespedia (talk) 10:55, 25 August 2009 (UTC)

I don't really understand your question. If you are asking "why does my phone continue to issue DTMF tones after I've dialled", then there are two reasons. Firstly normal phones can't tell if a call has completed - they'd dumb, and just send DTMF tones whenever you push buttons, and it's the exchange's problem to figure out call state. Secondly, even when phone systems are smart (like mobile telephony and VoIP) and do know if a call has been dialled okay, DTMF is used by IVR systems, voicemail, etc., so the handsets have to continue to send them as needed. Indeed, systems which don't use DTMF for call setup (e.g. VoIP systems like Skype) still have to have little DTMF-emitting virtual keypads, so IVR and voicemail apps still work. -- Finlay McWalter • Talk 12:23, 25 August 2009 (UTC)

Phone keyboard

strange symbol on the one key

Why the number 1 on the phone keypad (mostly on mobile phones) has a "o_o" sign? What is it and how does it come from?--Mikespedia (talk) 11:16, 25 August 2009 (UTC)

It's been there on every mobile I've ever owned and on a press-and-hold always connects me to my voice mail box. Since it looks like a stylised tape, I would suggest that. It doesn't seem to be part of any international standard such as E.161. Nanonic (talk) 11:29, 25 August 2009 (UTC)

voicemail —Preceding unsigned comment added by 82.43.89.136 (talk) 12:25, 25 August 2009 (UTC)

voice mail recorder for fixed phones also uses tapes. I have seen in English movies. --V4vijayakumar (talk) 14:28, 25 August 2009 (UTC)

It's funny that we still use the "tape" metaphor when it's incredibly unlikely that tape will be all that useful in the future. Then again, the floppy disk as a universal "save" icon is pretty similar, in that respect. --68.50.54.144 (talk) 21:53, 25 August 2009 (UTC)

Sleepy Hard Drive

You know when you leave an external hard drive inactive for about 5 mins it goes into power save mode? How can I make it do that on command? —Preceding unsigned comment added by 82.43.89.136 (talk) 12:22, 25 August 2009 (UTC)

On Linux you can say "hdparm -Y /dev/yourdrive". More options here. --Sean 13:14, 25 August 2009 (UTC)

In windows go to "control panel", and look for something called "power options" or similar - there you will find various options to control when stuff turns off, and how long before it does that.83.100.250.79 (talk) 13:44, 25 August 2009 (UTC)

How do I get songs off of my iTouch iPod onto my new laptop for free?

I created a new iTunes on my new laptop and burned some CD's onto it so there is about 50 songs on my iTunes. However, there are 500 songs on my old iTouch that I want to download onto my laptop but it keeps asking me to erase everything on my iTouch. How do I avoid this? --Reticuli88 (talk) 13:53, 25 August 2009 (UTC)

Try iRepo; you can use if for free (you just have to repossess each song one by one) or you can pay something along $19.99 to do them all at once. I used the free for 600 songs, just because money is tight. It took like thirty minutes. It was really easy to use, though. Hubydane (talk) 15:56, 25 August 2009 (UTC)

How to add to file to a zip file?

How to replace a file (/dir1/file1) to a zip file (/dir2/zip), without renaming the zip file; without adding any directory hierarchy like, 'dir1/file1' to zip file; and without '.zip' file extension. I tried all options like, 'rjufmTb' and combination, but none of them are working. --V4vijayakumar (talk) 14:09, 25 August 2009 (UTC)

I assume you're using linux, since you're using a forward slash as a directory separator. If I understand your question correctly, this achieves what you want to (Tested on my Debian box, in a directory which initially is empty):

     mkdir dir1
     mkdir dir2
     echo "First version of file1." > dir1/file1.txt
     echo "This is another file in directory dir1." > dir1/another_file.txt
     zip -r dir2/foo.zip dir1
     # ********** Now wait three seconds... **********
     sleep 3s
     echo "NOTE: file1.txt is now updated to second version." >> dir1/file1.txt
     zip -u dir2/foo.zip dir1/file1.txt

I had to add sleep 3s to make zip understand that the file actually had changed, otherwise things were happening too quickly for the time-stamp to change, and therefore, the file wasn't updated in the zip file. --NorwegianBlue ^talk 20:01, 25 August 2009 (UTC)

Retaining leading quote in Excel

As many will know if you insert a leading quote ' in an Excel cell it will display the following text as entered without the quote, e.g., '01 will display the cell contents as 01. If I want to keep that leading quote I can't find how to do so (have tried many different Number Cell Formats and they don't seem to work).

The issue is I'm trying to get a Concatenate formula to work correctly but am hitting this issue. Abbreviated form of formula showing key part is:

CONCATENATE("*[[:",B4,"|",D4,"]]")

Now say cell B4 contains text with a leading quote, my concatenate formula loses the quote, when I want to keep it in the formula result. I can solve the problem by using two quotes instead of one (so that the first one is 'lost', and the second one becomes the de facto required first quote), but that's not my preferred solution. Any ideas? --jjron (talk) 14:14, 25 August 2009 (UTC)

CONCATENATE("*[[:'",B4,"|'",D4,"]]")? (Your formula plus a couple of added apostrophes.) Now you get an apostrophe every time, irrespective of the source. I'm struggling to understand why you wish to retain the apostrophe when it looks as if you are constructing some wikimarkup. Meanwhile I have checked that IF statements appear unable to recognise the leading apostrophe, which seems to rule out that approach. --Tagishsimon (talk) 14:48, 25 August 2009 (UTC)

Yeah, right on the wikimarkup, but the solution doesn't work. The reason I want to keep the apostrophes (but not hard code into the formula), is because sometimes I want italics (e.g., for species names) but usually not - to get the italics I want to enter ''Homo sapiens'' into B4 and have it work in my concatenate formula when I join it with some non-italicised text. As I say I can just enter '''Homo sapiens'' and it works, but it annoys me that I can't get Excel to do exactly what I want it to! :-) --jjron (talk) 14:55, 25 August 2009 (UTC)

I share your annoyance in this instance. You could enter all of your italic data as '''Foo'', although in the long term this might result in apoplexy. You could enter your species as plain text, have another column indicate it is a species, and then use a conditional formula to construct the wikimarkup. It does look to me as if you'll have to use some sort of workaround. --Tagishsimon (talk) 15:18, 25 August 2009 (UTC)

Hmm. You could attack the problem with visual basic. Interesting read. --Tagishsimon (talk) 20:53, 25 August 2009 (UTC)

My Roller Coaster Tycoon 3 has an error!

I loads fine, but there is this annoying box in the upper left hand corner that has the games logo, and it wont go away.Accdude92 (talk) (sign) 14:29, 25 August 2009 (UTC)

A screenshot would be nice if you could link it (but, for obvious reasons, don't upload it here). — neuro^(talk) 20:49, 25 August 2009 (UTC)

Windows Live

So I asked on here and the answer worked... But then evidently something changed, because my email address ***@email.lmc.edu now only receives messages. When I try to send messages I get a server error message. Help, please! Hubydane (talk) 15:54, 25 August 2009 (UTC)

What error are you getting? "Server error" sounds like HTTP 500 (which you can't do anything about) or a misconfiguration of settings in your client. Make sure the server is set to "smtp.live.com", port 25, SSL, and check that the username is set to your e-mail address. Xenon54 (talk) 20:42, 25 August 2009 (UTC)

multi-audio, multi-subtitle MKV file

Dear Wikipedians:

I am looking for a small, sample MKV file that contains multiple audio streams and multiple subtitles. I want to test it out in Windows Media Player to see how I could switch between the audio and subtitle tracks.

BTW, are there any MKV files out there that contain multiple video streams? So that I could switch between multiple videos, perhaps even have a picture-in-picture?

Thanks.

70.29.26.86 (talk) 16:17, 25 August 2009 (UTC)

http://dl.eve-files.com/media/0906/test.mkv is the only one I could find. 30 seconds of some MMORPG, but only one video track. At least you will be able to tell if WMP can play them or not. No problems with playing it for me under Ubuntu. I can tell you that VLC media player (free for just about every OS in existence) has a "Audio" menu and a "Video" menu to switch between different tracks, but there is only one track on this file. I'm sure WMP has a similar mechanism. This forum thread might be of interest to you as well. Xenon54 (talk) 20:53, 25 August 2009 (UTC)

For how long will Google retain its advantage?

Various companies have thrown and will continue to throw tons of money at research into search engines so long as Google enjoys its profit margin. Academic research will continue as well. How hard is it, how long will it take before someone figures out the magic behind Google? 67.243.4.208 (talk) 16:22, 25 August 2009 (UTC)

Even if a search engine of equal quality came along, google still holds it's ground because of its name. Everyone knows google. —Preceding unsigned comment added by 82.43.89.136 (talk) 16:25, 25 August 2009 (UTC)

They also have a lot of invested capital. One of the hallmarks of current state-of-the-art web search is that it requires enterprise computing - that is, enormous data centers. These aren't cheap. Even if some new technology came around, it would be hard to ramp up to the same magnitude - a ten-thousand server datacenter will cost millions of dollars, and barely scratch the surface of what a large organization can deliver in terms of performance and availability. When Google got its start in the 1990s, it was possible to host a competitive, mainstream website on three or five computers (and later, a few hundred systems); today's internet volume is much higher and requires a more entrenched technology solution. However, I am not surprised to see Google's market share eroding[10] as the concept of "internet search" falls from "high-tech" to "commodity". This sort of categorical change in the technology will result in different business strategies as various companies vie for the internet audience. Nimur (talk) 17:14, 25 August 2009 (UTC)

Unknown hard error

I like to play Age of Kings on my Windows 2000 PC. It's a ropey old thing, prone once every couple of months to spates of hanging or crashing, and it's very bad at running Age of Kings - it tends to freeze once in a while and spin the CD for ages. Just now I had a spectacular crash, which dumped me into the desktop with an alert box that just said "unknown hard error" and an "OK" button. Nothing else on the screen would respond to clicks, and when I pressed ctrl-alt-delete, instead of task manager the PC just restarted. It then couldn't find my boot disk. Fortunately when I turned it off and on again it was in a better mood and everything was fine.

I think this is my favourite error message ever, so terse and baffling. What does it mean? 81.131.41.17 (talk) 20:54, 25 August 2009 (UTC)

Mobile phone comparison matrix

What websites or tools can I use to drill down the mass amount of mobile phones being offered by the manufacturers?

I'm looking for something similar to http://www.wikimatrix.org/. i.e.: Being able to select phones from a range of criterias, then being able to compare them side by side.

Thanks! --jcmaco (talk) 22:17, 25 August 2009 (UTC)