Wikipedia:Reference desk/Archives/Computing/2009 July 13

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July 13[edit]

Internet Explorer opacity support[edit]

Is there any way I can get IE7 to render opacity like <div style="opacity: 0.5"> or doubly -moz-opacity?

In a proper browser,

this text

is 50% transparent. Is there any possible way to get IE6 or IE7 to render that properly?-- penubag  (talk) 08:49, 13 July 2009 (UTC)[reply]

See http://www.quirksmode.org/css/opacity.html , which lists two different ways for two different ranges of IE versions. 87.114.25.180 (talk) 10:45, 13 July 2009 (UTC)[reply]
Thanks for that link, it help a lot! -- penubag  (talk) 20:38, 13 July 2009 (UTC)[reply]

Open source Flash[edit]

1st: Is there any advantage for the end-users to use open source Flash instead of Adobe Flash? 2nd: If I develop a .swf using the Open source approach, but the client needs a .fla file. How can I get this .fla file? Would decompiling my open source .swf work?--Quest09 (talk) 11:10, 13 July 2009 (UTC)[reply]

1. no. 2. probably not very well. --98.217.14.211 (talk) 18:28, 13 July 2009 (UTC)[reply]
There are advantages of free SWF players. Both Gnash and SWFdec support non-x86 machines and SWFdec supports saving media files used by Flash (e.g. movies from YouTube or similar sites). MTM (talk) 18:01, 17 July 2009 (UTC)[reply]

doubt!![edit]

The first programmed unix was written in which programming language?? —Preceding unsigned comment added by 122.164.109.75 (talk) 13:15, 13 July 2009 (UTC)[reply]

Ken Thompson and Dennis Ritchie were assembly language programmers. After getting the basics of Unix running, and after Ritchie had developed the C programming language, C was used to write Unix. -- kainaw 13:32, 13 July 2009 (UTC)[reply]

Thanks .... a dumb friend of mine told me it was cobol !!! —Preceding unsigned comment added by Sushil shenoy (talkcontribs) 13:43, 16 July 2009 (UTC)[reply]

First computer language[edit]

In what computer language was the compiler of the first computer language written?--Quest09 (talk) 15:47, 13 July 2009 (UTC)[reply]

Perhaps A-0 programming language? I'm no computer history buff but the article suggests it was the first Compiler ever developed for an electronic computer. ny156uk (talk) 15:51, 13 July 2009 (UTC)[reply]

You may also be interested in History of compiler writing which is linked within that article. ny156uk (talk) 15:52, 13 July 2009 (UTC)[reply]

The first compiler would have been written in assembler - before we had compilers - that was pretty much it. SteveBaker (talk) 02:41, 14 July 2009 (UTC)[reply]
Unless anybody wants to start a messy debate about blurry definitions of "compiled code" on antique computer architectures, let's just all agree with Steve and move on with our lives... Nimur (talk) 05:02, 14 July 2009 (UTC)[reply]
Do you have any evidence that it was written in assembler? The article Assembly language says assembly language was developed in the 50s, while A-0 dates back to 1951, but there's not much information about the implementation of A-0. Before assembly languages, programs were entered in numeric machine codes, and programmers would have to know the code corresponding to each instruction. --Boris straight (talk) 17:11, 15 July 2009 (UTC)[reply]

Hard drive failure?[edit]

One of my desktop PCs has suddenly started reporting "missing system disk". The problem is that the disk is either found at POST or it is not found at POST. If it is found, then the PC boots into Windows XP with no problem. Re-seating the IDE and power cables seems to have fixed the problem for the time being and I have managed to retrieve important documents. I am considering buying a new disk and reinstalling Windows, but I would like to be sure it is the disk at fault and not something else like wobbly cables. Is there a way of telling if the disk is actually faulty? Astronaut (talk) 16:40, 13 July 2009 (UTC)[reply]

I've had badly kinked IDE cables that lead to intermittent connections (leading to weird behaviour), so swapping that is a first measure. Secondly make sure you're really getting enough power on the power rails running the drive (with a multimeter into a spare molex connector); new hardware (like more disks, or a fancier graphics card) can cause the power rail to be a tad low, which means things sometimes work and sometimes don't. 87.114.25.180 (talk) 16:46, 13 July 2009 (UTC)[reply]
But, apart from the cables, the disk could be starting to lose the boot record sector, which means one day it won't be recognised at all, and that's that. So rescue what you want from it right away. (Though I used one for 6 months like this before it finally totally died). If replacing the cables etc then stops the problem, you can feel safe using it.- KoolerStill (talk) 18:15, 13 July 2009 (UTC)[reply]
A bad boot sector won't prevent the machine from seeing the drive at post, just from booting from it. It's perfectly simple to wipe the boot sector off a drive (e.g. with dd) and the drive shows up in BIOS fine. 87.114.25.180 (talk) 18:22, 13 July 2009 (UTC)[reply]

How to enter comands in Linux Ubuntu[edit]

After a lot of internet research I eventually found out that you use the "Terminal" to enter computer commands. (I hope I'm not breaking any Linux rules by revealing this closely-kept secret. Of course nobody actually wrote anywhere on the internet that you use the Terminal - that would make it too easy - but I deduced it by implication). But, when I click on Terminal on my Ubuntu computer, all I get is a blank white rectangle. It is just pure white - no text, no graphics, nothing. Is there any other way of entering commands please? 78.146.166.2 (talk) 16:53, 13 July 2009 (UTC)[reply]

Here are some beginning tutorials for using the linux command line: [1], [2], and [3] 87.114.25.180 (talk) 17:01, 13 July 2009 (UTC)[reply]

Thanks. Upon restarting the monitor now has a higher resolution and I can see the "Terminal", so its no longer a problem. 78.146.166.2 (talk) 18:05, 13 July 2009 (UTC)[reply]

You can also get a console by hitting ctrl-alt-f1 (f2, f3...). Hit ctrl-alt-f7 to return to the X gui. 87.114.25.180 (talk) 18:13, 13 July 2009 (UTC)[reply]

HP laptop quick buttons with VLC media player[edit]

I have an HP Pavilion dv4 laptop which has quick buttons for play/pause, stop, forward, backward. They work with Windows Media Player and Windows Media Center but not on any other program. Is there a way to make them work for VLC media player, iTunes, Real Player and others? I'm mainly interested in using the buttons with VLC but others would be nice. 95.84.64.174 (talk) 17:00, 13 July 2009 (UTC)[reply]

Why was download so slow?[edit]

This is the information about my computer.[4]

Over the weekend, I got one of these messages at the bottom of the screen saying I should download an update. I did, and while it slowed down all the web sites I went to (ESPECIALLY Wikipedia, but you were having a problem of your own), I continued to use the Internet during the process anyway. When I was ready to sign off the computer, it was still doing the second part of the process. So I clicked on the red X for the other stuff I had been doing and left the computer for a few hours. When I came back, nothing had changed (except I now got a "Welcome to Internet Explorer 8" message), and the screen that I thought I had clicked on the red X for was still sort of there. Parts of it were there. When I clicked on the red X again I got "not responding". A few minutes later, though, everything looked normal, and the downloading process appeared finished, and I felt confident shutting down. I knew that downloading new software requires restarting the computer, so I did that, and the third phase of the process was completed after I did that, so I shut down.

The next time I used the computer, I got a message saying I had new updates, and when I clicked, it showed "Internet Explorer 8", but it said "Failed". Now I have had that message appear, but the next time I signed on the computer, after a very, very slow download, the download went very quickly and was completed. I haven't had any such message this time. I don't know what slowed down the computer so much in phase 2 or why I haven't been told what to do for phase 4.Vchimpanzee · talk · contributions · 17:21, 13 July 2009 (UTC)[reply]

Sometimes Windows Update goes wrong, and doesn't seem to work. As you have found trying a second time (after a few hours) usually fixes the problem .
Question - is your computer ok now?
One thing to try is go to windows update (you can eaily find it by searching the internet), and make sure that there are no outstanding downloads (you only need the ones it automatically selects - the others are optional, and most people won't need them)
It sounds like the first download failed for some reason - when you restarted the computer it recognised this, and tried again - and by the sounds of it - worked.
Assuming the computer is working I'd put it down to experience - just a unidentified fault the first time. If there still is a problem please expand.83.100.250.79 (talk) 18:20, 13 July 2009 (UTC)[reply]


The windows update that includes internet explorer 8 is not an unattended install. A message about IE8 (for which you have to click 'next' 'next' 'ok/apply') failed to properly display (or opened in the background.) This hung-up the installation, which was manually aborted. Your computer successfully recovered from this error by error checking its first download against the server source (which is why the second download was fast, there wasn't much of one) and re-installing the patch. You can manually check for updates again, but it sounds like windows took care of itself. Taggart.BBS (talk) 18:22, 13 July 2009 (UTC)[reply]

Yes that sounds far more likely than my above comment about a 'bad download' - though I still maintain that windows update has issues periodically.83.100.250.79 (talk) 18:29, 13 July 2009 (UTC)[reply]
I don't know if there was a "second download". But that comment about needing to say "OK" makes sense. It may be I was supposed to click on that second message, which wasn't there hours earlier. It still says "Failed" on the update history.
Other than that, the computer has been working fine today and so has Wikipedia.Vchimpanzee · talk · contributions · 18:54, 13 July 2009 (UTC)[reply]
Wait, there was another update today, and it says the same thing as the other one about Internet Explorer 8. It's just waiting for me to restart.Vchimpanzee · talk · contributions · 18:57, 13 July 2009 (UTC)[reply]
What does it say ? Does it say that IE 8 successfully installed, and you need to restart for it to initialise, or something else?83.100.250.79 (talk) 19:25, 13 July 2009 (UTC)[reply]

Sorry, I got busy and never got around to posting this. I have restarted the computer and I got a special welcome inviting me to see all the features of Internet Explorer 8. It's done.Vchimpanzee · talk · contributions · 13:38, 14 July 2009 (UTC)[reply]

Recognising wireless cards by "noise"[edit]

Tin foil hat man changes his mac address very frequently, but he is worried if it's possible for the black helicopters to identify him by using a big antenna to listen to some unique background noise/errors in the signal/something you can listen to with an antenna his laptop with wifi generates? --194.197.235.56 (talk) 17:33, 13 July 2009 (UTC)[reply]

It would be very difficult. If someone tried very hard, they could probably distinguish between one 801.11x transmitter and another from tiny variances in the performance of analog components in the transmit circuitry, or drift rate of the transmitter's internal clock. But it's likely that these will vary over time, and due to external factors like temperature, making this a very difficult process. In practice anyone with equipment that sensitive can just sniff your screen with Van Eck phreaking and identify you 'cos you've always got the same Cindy Crawford desktop wallpaper. 87.114.25.180 (talk) 17:53, 13 July 2009 (UTC)[reply]
It's a lot more practical to distinguish between one model of card and another. Cards with different firmware will take slightly different times to respond to signals, which may be enough to distinguish them. The same analog electronic components mentioned above, which will be fixed for fairly long production runs, subtly shape the output waveforms generated, and different models will use different circuits. To use this in practice the snooper would have to have a very extensive library of signal traces from every card (and each time the factory specifies a different component the trace will change) - that's a huge amount of trivial work, but such is the lot of forensic scientists already, with their massive collection of shoe prints and button designs and bat eyelashes. 87.114.25.180 (talk) 18:02, 13 July 2009 (UTC)[reply]
They probably just look for people who's MAC address changes suspiciously frequently! SteveBaker (talk) 02:39, 14 July 2009 (UTC)[reply]

perl script[edit]

I'm trying to run [wakaba.c3.cx/ this script] on XAMPP server but I keep getting this error message:

Server error!

The server encountered an internal error and was unable to complete your request.

Error message:
Can't locate config.pl in @INC (@INC contains: . C:/xampp/perl/site/lib/ C:/xampp/perl/lib C:/xampp/perl/site/lib C:/xampp/apache) at C:/xampp/htdocs/img/wakaba.pl line 16. BEGIN failed--compilation aborted at C:/xampp/htdocs/img/wakaba.pl line 16. ,

If you think this is a server error, please contact the webmaster.
Error 500
localhost
13/07/2009 06:55:30 PM
Apache/2.2.11 (Win32) DAV/2 mod_ssl/2.2.11 OpenSSL/0.9.8i PHP/5.2.9 mod_perl/2.0.4 Perl/v5.10.0

What do I have to do to fix this? —Preceding unsigned comment added by Onesevensix 77 (talkcontribs) 17:57, 13 July 2009 (UTC)[reply]

You must put a file called "config.pl" in C:\xampp\perl\site\lib\ or one of the other directories listed. The installation instructions will probably tell you how to find or create that file. --Sean 21:00, 13 July 2009 (UTC)[reply]

MS Excell (also star/open office)[edit]

Probably the ultimate dumbo question : Once a value has been entered into a cell I can't find a way to edit the value except by going up to the 'equation editor' - clearly this is inefficient as I have to move my hand at least 1" to move the mouse cursor there - is there a way to change a value in a cell once it has been entered into the cell.? 83.100.250.79 (talk) 18:14, 13 July 2009 (UTC)[reply]

At least in OpenOffice Calc, I move the "cursor" box around with arrow keys, and anything I type goes into the cell. If I move the box elsewhere, then back and type then that just overwrites the cell contents. I never have to go to the text field at the top. I'm pretty sure Excel works the same. 87.114.25.180 (talk) 18:18, 13 July 2009 (UTC)[reply]
Click in the cell and overtype it??? To change only part of the content you need to use the top field, unless you look in tools or preferences for a setting that lets you "edit in the cell". - KoolerStill (talk) 18:23, 13 July 2009 (UTC)[reply]
Yes overtyping is a right royal pain in the, I just want to edit one digit of many - you can imagine my frustration... I'll have a look and see if I can find a setting (I think I tried that before and couldn't find it) 83.100.250.79 (talk) 18:26, 13 July 2009 (UTC)[reply]
In Excel it's Tools > Options > Edit > Edit directly in cell. I don't have OpenOffice. - KoolerStill (talk) 18:45, 13 July 2009 (UTC)[reply]
In Excel, you can press F2 or double-click a cell to edit it directly. 95.84.64.174 (talk) 19:07, 13 July 2009 (UTC)[reply]
I'm sure I tried double click, and it didn't work - will try it again. 83.100.250.79 (talk) 19:23, 13 July 2009 (UTC)[reply]

You're all right - I think I was getting confused because I expected it to work like a browser box input window - one click to select all, arrow to move cursor inside box - that is of course impossible if the arrow keys are to navigate through cells as well.. It's official - I'm stupid..

Resolved
(Don't be so hard on yourself -- after all, you /are/ dealing with a Microsoft product! --DaHorsesMouth (talk) 23:34, 13 July 2009 (UTC))[reply]

DIV with relative position still taking space[edit]

Hi Wikipedians,

I'm about to go nuts, I cant figure out how to make the extra space disappear! Oh yeah, here's whats happend. I had to use relative positioning to get a search bar where I needed it, and I declared this div above a table, and got it to show up in the right place, but I'm peeved to discover this has forced the table rendering lower than it should be (I suspect the height of the div is still being rendered on top of the table despite that the div being repositioned). I know its the positioned div 'cause when I comment it out the space goes away. I guess looking at it would make more sense: my frankenstein.

heres what I have for the div:

 <div class="pSearchBar">
    <form action="/SearchResults.asp" method="get" name="SearchBoxForm">
    	<span style="color: white; font-size: 18px;">Search <input style="width: 200px;" type="text" maxlength="30" value="" name="Search"/>
        	<img src="vspfiles/templates/Prince/myimages/images/gobutton.png" border="0" style="cursor: pointer; vertical-align: middle" onclick="document.forms['SearchBoxForm'].submit();" />
        </span>
    </form>  	
 </div>

 ... table goes here ...

Here's the CSS:

.pSearchBar {
	position:relative;
	width: 300px;
	left: 670px;
	top: 94px;
	height: 50px;
}


Any suggestions how I can keep the search bar there while removing the extra space on top?

TIA PrinzPH (talk) 21:29, 13 July 2009 (UTC)[reply]

Have you tried it without the FORM element? FORM elements add space if I recall (though you can probably get rid of it by playing with its CSS). When debugging weird DIV things, always try it without the content of the DIV to see if that is causing the problem. (Obviously the only way to tell if that is the case is to add a temporary border to the DIV, but that is easy enough). --98.217.14.211 (talk) 00:03, 14 July 2009 (UTC)[reply]
You might try nested div span elements like:
        <div style="position:relative;">
          <div style="position:absolute; left: 400px; top: 50px; border:solid; background-color:yellow;">
            Sample text.
          </div>
        </div>
The outer div defines an empty box relative to the surrounding content, which serves as a reference to which the inner box is positioned. (You may not need this if you already have a suitable container such as a table cell or if you want the inner element to be positioned relative to the entire page.) The position:absolute attribute of the inner div removes its content from the normal flow, so it will not take up space. If you change the outer element to a span instead of a div, no break occurs and the inner box is positioned both vertically and horizontally relative to the surrounding content. There may be a better way, but this is what I came up with through experimentation. I would verify expected results across multiple browsers, and of course all of the style attributes can be moved to a CSS file. -- Tcncv (talk) 01:08, 14 July 2009 (UTC)[reply]
Off topic but why do you need to define the position in the first place? Can't you just pop it in pScarletUpper2 next to your buttons? Your code is a strange mix of table and CSS based layout and is littered with <br> tags later on. Are you using a WYSIWIG editor? Also, naming your styles after its colour is bad practice as it will make no sense at all when the styles/colour change later on; name it after its purpose instead. --antilivedT | C | G 01:25, 14 July 2009 (UTC)[reply]
Thanks for the inputs! :) @Tcncv - will try it out. @Antilived It's a mess I agree. I eventually want to learn to use pure CSS, I guess im still 'transitional' having to fallback to tables when I'm too dizzy with CSS. Eventually I'll man-up and pull it off! But seriously, thanks for the input, am beginning to learn a lot! :D PrinzPH (talk) 23:15, 14 July 2009 (UTC)[reply]

Trojan[edit]

Anyone got some info on Trojan.Win32.Vapsup.uxx came across it on my system today thanks. BigDunc 21:56, 13 July 2009 (UTC)[reply]

McAfee's virus library is pretty good resource for these things. This page (http://vil.nai.com/vil/content/v_150856.htm) has the closest match I can find but not sure how much use it is info-wise. ny156uk (talk) 22:18, 13 July 2009 (UTC)[reply]

This page (http://www.pctools.com/mrc/infections/id/Trojan.Vapsup/) may also be of use. There is an e-how page on this but Wikipedia is stopping me linking (Something about blacklisted, but a google search term of 'Trojan.win32.vapsup' should return the e-how article ny156uk (talk) 22:21, 13 July 2009 (UTC)[reply]