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April 5

Working on many files in unix

I need to write a bash script to run a program against all the files in a directory tree. The program takes two arguments, the input filename and the output filename where the output filename should be the same as the input filename but with a suffix added. So, for one file it works something like this: program -i filename -o filename.suffix. For many files I thought about using the find command, but can't get either the -exec action of find or xargs to work with the filename appearing twice or with a shell function. So that is something like:

find . -type f -exec program {} {}.suffix ;

or

afunc()
{
   program $1 $1.suffix
}
 
find . -type f -exec afunc {} ;

The first reports "find: missing argument to `-exec'". The second reports "find: `afunc': No such file or directory".

I am also looking for a way to avoid processing a file which has already been processed (and ending up with 2 suffixes) and for a way to report and act on any error messages the program might produce, but without stopping the script. Astronaut (talk) 09:26, 5 April 2013 (UTC)

The first case should end in ;\ so

    find . -type f -exec program {} {}.suffix ;\

The second case can't work because afunc is a name inside this bash script, and program is a subprocess of a subprocess of that shell. You can create another script and have find's exec call that. Personally my bash scripting is weak and I devolve anything but simple tasks to a Python script (where os.walk does the hard work). -- Finlay McWalterჷTalk 10:53, 5 April 2013 (UTC)

Shouldn't it be \; rather than ;\ ? (That is, you want to escape the semicolon argument required by find from being misinterpreted by the shell as a command separator.)—Emil J. 14:11, 5 April 2013 (UTC)

Oops, yes, it should. -- Finlay McWalterჷTalk 14:12, 5 April 2013 (UTC)

• I've written probably thousands of scripts that do things like that (neuroscience data analysis), and I recommend using a "for" loop. You can probably use $(ls -r) or something similar to generate a list of files. I have always used C shell because I know it better, so I can't be very helpful about the specific syntax, but I've always been able to make that method work pretty easily. Looie496 (talk) 15:32, 5 April 2013 (UTC)

If you make your afunc into a shell script (a file, rather than a shell function in memory — sad that it's a redlink, since shell functions are quite useful; we do discuss them a bit at alias (command)), find will be able to invoke it (perhaps as ./afunc.sh). If you write the script as

#!/bin/bash
for t; do
  program "$t" "$t".suffix
done

you will be able to pass multiple files to it (as with most commands), and then you can use find -type f | xargs ./afunc.sh (or, to properly handle unusual file names, find -type f -print0 | xargs -0 ./afunc.sh). (When the actual command, rather than a wrapper script, accepts multiple arguments, using xargs is also more efficient.) There is likely also a syntax -exec ./afunc.sh {} + that is similar to using xargs, including that you cannot do {} {}.suffix this way.

As for not double-processing, you can ask find to exclude files whose names match a pattern: find -type f \! -name \*.suffix .... (The ! and * are like ; in that they are special to the shell and so must be escaped to be delivered intact to find.)

As for error messages, by default they appear on stderr, and it can be a bit of a pain to intercept and interpret that. However, any properly-designed program will have an exit status you can use. Just like -type f specifies a condition, -exec ... \; does too: it "passes" if the command reports that it is successful. In this fashion you can make a sort of "find script" that does things for each file for which processing succeeded or failed:

find -type f -exec program {} {}.suffix \; -print # name the files that worked
find -type f \! -exec program {} {}.suffix \; -print # name the files that failed
# Complicated example: run additional programs on each success/failure:
find -type f \( -exec program {} {}.suffix \; \( -exec success {} \; , -true \) -o -exec failure {} \; \) \)

Alternatively (and more powerfully), you can do this in your shell script (whether it supports multiple files or not):

#!/bin/bash
program "$t" "$t".suffix && echo "$t" # name file that worked
program "$t" "$t".suffix || echo "$t" # name file that failed
# Complicated example: run additional program depending on success/failure:
if program "$t" "$t".suffix; then
  success "$t"
else
  failure "$t"
fi

The shell is also capable of doing things like checking for preexisting suffixes, checking for preexisting files you might not want to overwrite, and capturing stderr if that turns out to be necessary. --Tardis (talk) 16:02, 5 April 2013 (UTC)

online shop stuff

The trouble with selling stuff online is that you can either pay to use various services, such as amazon, ebay, paypal and so on, or it works out cheaper and easier to sell through your own website, but they cost so much more and take more time and effort to set up to start with. So, I had this idea of setting up a website where people pay a small fee for a subdomain and a template to sell through, in particular it gives them a platform through which to automate the use of various payment services, particularly accepting debit and credit card payments and such like. But the question is, this being my website but with other people using it to sell their stuff, would they use my merchant payment accounts, or would each person need to set up their own to arrange these transactions separately?

And in general, would this idea work, or is there something else that I haven't thought of?

Kitutal (talk) 19:35, 5 April 2013 (UTC)

I’m not sure I see how it would differ from existing services of the type you already mentioned. ¦ Reisio (talk) 19:44, 5 April 2013 (UTC)

There already exist services like you describe. Shopify is a big one, but there are a number of others.

So it's certainly possible. APL (talk) 19:45, 5 April 2013 (UTC)

Yahoo also offers a similar service : SmallBusiness.yahoo.com/ecommerce.

APL (talk) 19:49, 5 April 2013 (UTC)

April 6

Check HD for errors

Carbonite says that my HD (on a Windows 8 system, NTFS) has a lot of errors when trying to read. Spinrite is supposed to test the HD and map out bad areas. Are there alternatives that do that (TestDisk may be one)? Bubba73 ^{You talkin' to me?} 01:13, 6 April 2013 (UTC)

Is CHKDSK still on Windows 8 ? It works, but it does take forever, so run it overnight (maybe one night for each disk). StuRat (talk) 01:57, 6 April 2013 (UTC)

Yes, it is still there. At first I ran it without the /R parameter, which it should have. But I ran it again. I had to tell it to do it when it reboots, and it only gives a % done, so I didn't get a report of errors. Bubba73 ^{You talkin' to me?} 13:33, 6 April 2013 (UTC)

What exactly is the error you're getting from Carbonite? If it's complaining about I/O errors, you need to get a new hard drive. If it's complaining that, say, it can't read a particular file, that probably just means the file is open in another program. Either way, chkdsk and Spinrite are unlikely to help. -- BenRG 04:35, 7 April 2013 (UTC)

Antivirus companies creating viruses

I read some time ago that an antivirus software company (or companies) had been caught creating viruses in order to boost or drive sales of their software. I can't remember much more detail than that. I'm looking for articles (on Wikipedia or news sources) that detail these actions or allegations. Thank you ahead of time. Vidtharr (talk) 18:40, 6 April 2013 (UTC)

There's evidence of that happening in China, as this story details. (The Epoch Times is not a very trustworthy source, but that story looks legit to me.) In spite of widespread rumors, that's unlikely to have happened in the US to any significant degree -- a company that did it would be risking its existence for a rather small gain. Looie496 (talk) 19:42, 6 April 2013 (UTC)

Not to mention, US companies could face lawsuits, damages, and maybe even criminal charges (IANAL). --Wirbelwind(ヴィルヴェルヴィント) 00:21, 7 April 2013 (UTC)

Not quite what you're talking about, but related: Rogue security software 38.111.64.107 (talk) 14:23, 9 April 2013 (UTC)

Problem with uninstalling Plustek USB scanner

I have a strange problem to solve: there is a PC with Windows XP, which has a Plustek USB scanner drivers and utilities installed. The files have timestamps from 1995–2000, directories were created in January 2008.

The hardware stopped functioning about 3 years ago and went to trash. Now I tried to cleanup the software, and ...the uninstaller refuses to work! It says:

Setup requires a different version of Windows. Check to ensure that you are running Setup on the Windows platform for which it is intended.

Error 102.

Possibly the Service Pack 3 has changed something in the system, so that the uninstaller no longer recognizes it. What can I do to properly remove the scanner software? --CiaPan (talk) 23:29, 6 April 2013 (UTC)

I've used the free version of Revo Uninstaller when a program's own uninstaller fails. -- Finlay McWalterჷTalk 23:30, 6 April 2013 (UTC)

April 7

Download

Hi all,

Could you please answer this question about IT (I don't know much about it). If I download a file and then put it on a USB stick, does the file have any "print" of my computer? I mean, can anyone know this file was downloaded to my computer before being transferred to the stick? Thanks a lot!

92.97.154.11 (talk) 02:05, 7 April 2013 (UTC)

Assuming you meant "Does it leave any trace ?", then, probably, yes. To be certain to avoid this, you'd probably need a read-only operating system, which can't possibly save any info, or you'd need to reformat the entire hard disk, after. Otherwise, some kind of tracker program running on the computer could keep a record, no matter how hard you try to prevent it.

However, saving directly onto the USB stick instead of first to the hard drive might minimize the trace, such that only the names of the files and times of downloads are stored on the hard disk, assuming nobody has installed a tracker program. StuRat (talk) 02:42, 7 April 2013 (UTC)

To remove any trace of your download:

Do as StuRat said and delete your browsing history for that time period so it doesn't look suspicious.

RunningUranium (talk) 02:59, 7 April 2013 (UTC)

The OP actually seems to be asking whether the file on the USB stick can be traced back to his computer, and the answer is almost certainly no. The file should be passed untouched from the download to your hard drive to the stick, and won't have anything added by your computer. Rojomoke (talk) 04:38, 7 April 2013 (UTC)

It will depend on the file though, some things like Microsoft Office documents tag the 'author' of the document - so if it was created on the PC and transferred to the USB it may still include the name of the computer (not necessarily something that will make it easy/realistically possible to track down the PC though). E.g. at work our laptops get a unique number as their 'name', any Word documents I create on it show that number in the author field in the properties. ny156uk (talk) 08:02, 7 April 2013 (UTC)

True, but the possibility of that will be much reduced if you don't open the file (with Word or whatever program it comes from) before passing it on. If the OP could tell us what kind of file it is, we could give a more definitive answer. Rojomoke (talk) 08:41, 7 April 2013 (UTC)

HD tune results

I'm running HD Tune (see above) and at this point the results show

HD Tune Pro: ST32000641AS Health

ID                                  Current  Worst    ThresholdData         Status   
(01) Raw Read Error Rate            118      99       6        189990865    ok       
(03) Spin Up Time                   100      100      0        0            ok       
(04) Start/Stop Count               100      100      20       119          ok       
(05) Reallocated Sector Count       100      100      36       0            ok       
(07) Seek Error Rate                87       60       30       469998064    ok       
(09) Power On Hours Count           82       82       0        16046        ok       
(0A) Spin Retry Count               100      100      97       0            ok       
(0C) Power Cycle Count              100      100      20       118          ok       
(B7) (unknown attribute)            100      100      0        0            ok       
(B8) End To End Error Detection     100      100      99       0            ok       
(BB) Reported Uncorrectable Errors  100      100      0        0            ok       
(BC) Command Timeout                100      99       0        1            ok       
(BD) (unknown attribute)            100      100      0        0            ok       
(BE) Airflow Temperature            60       57       45       689831976    ok       
(BF) G-sense Error Rate             100      100      0        1            ok       
(C0) Unsafe Shutdown Count          100      100      0        46           ok       
(C1) Load Cycle Count               100      100      0        119          ok       
(C2) Temperature                    40       43       0        40           ok       
(C3) Hardware ECC Recovered         54       27       0        189990865    ok       
(C5) Current Pending Sector         100      100      0        0            ok       
(C6) Offline Uncorrectable          100      100      0        0            ok       
(C7) Ultra DMA CRC Error Count      200      200      0        0            ok       
(F0) Head Flying Hours              100      253      0        16368        ok       
(F1) LifeTime Writes from Host      100      253      0        -1989403685  ok       
(F2) LifeTime Reads from Host       100      253      0        -1902847635  ok       

Health Status         : ok

Looks like almost 190 million raw read errors. But it says OK. Do these error numbers seem reasonable? Bubba73 ^{You talkin' to me?} 03:24, 7 April 2013 (UTC)

From what I understand from [1], threshold is not the number of errors, but rather the limit. Your current test has 118 read errors, and before that the most number of errors was 99. The link I found doesn't show two values for Threshold. Maybe the program's help is more current or explains it better. RudolfRed (talk) 03:38, 7 April 2013 (UTC)

No, the "current", "worst", and "threshold" values are not counts of anything; they are abstract health values where higher is better and 100 (or sometimes 200 or 253) is normal. "Threshold" is a manufacturer-chosen constant value that's supposed to indicate the point at which you should think about replacing the drive. The "data" value is sometimes an actual count (as in "Power On Hours Count" and "Power Cycle Count").

The most relevant statistics here are the ones related to bad sectors: "Reallocated Sector Count", "Reported Uncorrectable Errors", "Current Pending Sector", and "Offline Uncorrectable". All of them are zero. That means the drive has never reported an I/O error to the operating system, so whatever error you're getting from Carbonite is not a drive hardware problem. -- BenRG 04:53, 7 April 2013 (UTC)

The HDTune test finished and those still show zero. You asked what error I was getting from Carbonite - it is a long story. I bought Carbonite HomePlus because one thing it does is make a mirror image of the HD to an external HD (which is a USB3 in my case). The docs say that it will take several hours to make the initial mirror image. It was taking a very long time. It was getting < 1% of the CPU and usually < 1% of the disc bandwidth. It was usually 0.1-0.2 MB/sec. Sometimes it would jump up to a few MB/sec and sometimes to 20-25 MB/sec. It was going to take several days at this rate, and I have only 300GB on the drive. I talked to Carbonite tier 1 and tier 2 tech support a few times, and some said that it just takes that long and others said that something is wrong. It finally finished after almost 6.5 days (155 hours). I think this is unacceptable because the mirror image is useless until it gets a complete image. (I had to reformat the external HD to do it, and had wiped a Microsoft drive image in the process, thinking that it would only take a few hours to do the new one. The MS one had taken only 3 hours.)

Anyhow, they bumped me up to tier 3 support, but it took more than a week for us to find a good mutual time. By that time the initial mirror image had completed. Tier 3 said that I had way too many HD errors. He said that my HD is so bad that the minuscule amount of processing that Carbonite is doing on it (about 0.1% of its capacity) is putting too much stress on it (which I don't believe). He said that the mirror image was useless because if my HD crashed and I replaced it and restored from the mirror image, what ever is wrong would cause the new drive to crash. And if I put in another new drive after that and restored, whatever is wrong would cause it to crash. (I don't believe this either, since if I have a H crash, it will be a head crash or other physical breakdown.) He wanted me to quit using the mirror image feature and refund part of my money and downgrade me to carbonite w/o the mirror image. I didn't want to do that, because I didn't really understand how it could cause a replacement drive to crash. He did turn off the daily updates of the mirror image.

So Carbonite software never gave me an error message, it just took a very long time for the initial mirror image. THe tech support people were all very nice, but they told me conflicting things and things I find hard to believe. Bubba73 ^{You talkin' to me?} 23:55, 7 April 2013 (UTC)

You should talk to a different support person, since that one has no idea what he's talking about.

Did HD Tune finish scanning the disk a few hours, or did it take days? If I understand correctly, you are not actually getting an error from Carbonite, it's just running slowly. Possibilities: 1. Another program may have been trying to access other files on one of the drives during the backup, causing a lot of back-and-forth seeking which can slow everything to a crawl. 2. There are a couple of SMART parameters above that do seem to show significant degradation: "Seek Error Rate" and "Hardware ECC Recovered". Both of those could conceivably slow things down. The next time you have this problem, you could look at the data values for those parameters in real time and see if they're increasing. 3. Maybe it's the backup drive that's failing; have you checked its SMART values? 4. There could be something wrong with the USB connection causing it to fall back to USB 1 speed. -- BenRG 05:32, 8 April 2013 (UTC)

HTTP Cookie

When a website is visited generally a cookie file is created at the server side then sent and stored in the client side.Is it possible for a human user to manually decrypt this cookie file with or without the help of some software tool.If so how?Will some Wikipedian elaborately expain this by giving an example? — Preceding unsigned comment added by Ichgab (talk • contribs) 07:17, 7 April 2013 (UTC)

You can view the contents of a cookie easily; most browsers have a simple function to do that. In Firefox it's rightclick -> viewPageInfo -> security -> viewCookies. But most cookies you'll see have a value that's just some random letters (or maybe a few labelled sequences of random letters). This isn't encrypted, so there's no decrypting to be done. Mostly cookies are like railway tickets: they have some numbers in them, and the important one may be a ticket number - but (unless you're a serious trainspotter) all the numbers are, from your perspective, essentially inscrutable. -- Finlay McWalterჷTalk 08:31, 7 April 2013 (UTC)

Not just one cookie either. Wikipedia has 14 cookies on my PC.--Shantavira|^{feed me} 14:36, 7 April 2013 (UTC)

Cookies aren't encrypted, although the values inside the cookie can be encrypted. For example, on the web site I work with, we store a session ID in the cookie, but encrypt it for security purposes. If the session ID wasn't encrypted, it may be possible for a hacker to hijack someone else's session. A Quest For Knowledge (talk) 14:50, 7 April 2013 (UTC)

android ≠ / = android

I bought my first android tablet (a cheap Ainol Novo7 Mars), that has a lot of chinese programs among with english ones and does not have my native language installed. It has now 4.0.3 system from manufacture's update. Can I install another android 4.0.3 or 4.0.4 system in it or even higher like 4.1.x or 4.2.x?--RicHard-59 (talk) 12:50, 7 April 2013 (UTC)

This video shows how to change the OS interface to English. Mostly you can only get OS updates from the manufacturer; the Android distribution from Google is intended for manufacturers, who configure it for their specific machine and add in stuff like device drivers for that particular platform. In a few cases you can get homebrew builds from enthusiasts, working to replicate the manufacturer's work. Looking at the NOVO7 article, it links to two CyanogenMod based firmware builds for the NOVO7; you should look into those, or in general check the CyanogenMod forums. -- Finlay McWalterჷTalk 13:12, 7 April 2013 (UTC)

I have the slightly older Novo 7 Basic and got useful advice from the forums at tabletrepublic. Their Novo 7 Mars forum doesn't have much content at present but would be a good place to ask for help. Flash my android is a forum with slightly more content, and has details of a 4.0.4 rom. I have no idea myself how good this rom might be.-gadfium 23:38, 7 April 2013 (UTC)

How old to learn Java?

When is the general upper limit, age-wise, for learning how to program in various code languages such as Java? Neuroplasticity degrades with age, so learning how to do it younger, I would image, would be best. If someone is in there mid-twenties, is it too late to learn how to program in Java well enough to make small Android apps? Acceptable (talk) 15:17, 7 April 2013 (UTC)

People tend not to go on degree courses once they get past 90 so I'd say somewhere around there is where one should perhaps give it a second thought. Dmcq (talk) 16:45, 7 April 2013 (UTC)

It’d probably be best to learn as much as early as you can, but there’s no particular reason to not learn it later in life if you have an interest. One might rethink learning Java™ for some other language that’ll have a better future, though. :p ¦ Reisio (talk) 17:30, 7 April 2013 (UTC)

I'm fairly sure that I pick up new programming languages now as fast as when I was 16 or 25 (and I have a lot more "experience" now ;-). I think Dmcq is spot-on. As long as you can hit the right key, you should be able to learn to program. --Stephan Schulz (talk) 19:56, 7 April 2013 (UTC)

There is a big difference, I might add, from learning Java as one of many programming languages you already know and learning Java as your first programming language. If you already more or less know how to program, especially OO languages, then adding Java can be done practically at any age over the course of a few weekends. If you're learning to program Java from nothing, that involves quite a lot more brain-stretching. In any case, I don't think mid-twenties is any kind of cutoff date whatsoever. I know people who have learned significantly new computing skills well into their 40s and I really don't see why there should be any significant cutoff well until one is very old indeed. To make an analogy, there are many people who learn how to play piano very late in life. Do any of them become brilliant virtuosos? Probably very few. But there is quite a lot of gulf between "enjoys playing piano" and "plays sold-out concert halls." I doubt someone coming to programming very late in life is likely to be the next genius programmer, but that doesn't mean they can't make apps or many other things. --Mr.98 (talk) 20:08, 7 April 2013 (UTC)

Linux Firefox download of .webm vs .flv

I downloaded a video from youtube using the plugin Flash Video Downloader, and selected the .webm file. The 306MB file took about three minutes to download. Just for a laugh, I decided to download the .flv version of the file and the 262MB took 29 minutes. Why should this take 10 times as long? --TrogWoolley (talk) 15:50, 7 April 2013 (UTC)

I'm not familiar with that particular extension (and the reviews for it don't persuade me that installing it is a good idea), but that performance hasn't been my experience, with similar extensions. FLVs, from YouTube or elsewhere, download many times faster than real-time for me, on a normal ADSL connection. It may be that your particular extension (documentation for which I failed to find) has code to deliberately choke FLV download speeds so it resembles the pattern of an actual Flash player (so as to thwart anti-download measures some cites may implement). If that's the cause, one would hope there was an option to disable that behaviour for sites, like YouTube, that don't care. -- Finlay McWalterჷTalk 16:04, 7 April 2013 (UTC)

You’d probably already watched the .webm version, and therefore already had it all cached somewhere, so the download was more of a move. ¦ Reisio (talk) 17:32, 7 April 2013 (UTC)

In my experience, different display resolutions will download at different speeds from YouTube. I don't know anything about the webm format, but what might be happening is that the FLV is at a smaller resolution than the webm file, which will download slower. With my downloading plugin for Firefox, when I choose 240p, I get ~50KB/sec. With 480p I get 150+ KB/sec, and with 720p I can get over 1MB/sec. -- 143.85.199.242 (talk) 15:43, 8 April 2013 (UTC)

April 8

Firefox prevent accidental quit

Because command-Q is sitting right there between command-W and command-Tab, it sometimes happens that I accidentally tell Firefox to Quit when all I really wanted to do was close a tab or a window, or switch to another app. And this is a problem, because I always have lots and lots of tabs and windows open (I'm not gonna say how many), all containing important state.

Once upon a time I had Firefox configured to warn me when I did this, but it seems to have disappeared with an upgrade somewhere along the way, and I can't find the option anywhere; now it just quits. Fortunately there's a workaround, of sorts: all I have to do is open $HOME/Library/Application Support/Firefox/Profiles/xyz.default/sessionstore.js, jump to the end of the 2 meg of JSON gobbledegook, find the string that says "state":"stopped", change "stopped" to "running", and restart Firefox, whereupon it graciously offers to restore all my tabs and windows for me. But I'd really like to find the old option, to automate or obviate this. Is there a low-level "every option ever" screen hiding somewhere, or do I need a separate plug-in for that, or what? —Steve Summit (talk) 02:51, 8 April 2013 (UTC)

In the location bar, go to about:config, search for “quit”. There’s another option for altering how the session/crash restore functionality behaves, and the keyconfig extension could disable CTRL+Q altogether for you. ¦ Reisio (talk) 05:04, 8 April 2013 (UTC)

You can apparently change the quit key to command-shift-Q by typing defaults write NSGlobalDomain NSUserKeyEquivalents '{"Quit Firefox" = "@$Q";}' in a terminal, or use the always-ask addon (both suggestions found here, not tested). -- BenRG 05:06, 8 April 2013 (UTC)

I don't know why you need to go into about:config when there's an option for this in the preferences. On my version of FF, it's under Preferences > Tabs > Warn me before closing multiple tabs. Dismas|^(talk) 07:50, 8 April 2013 (UTC)

Besides that he specifically asked for about:config, and that its location and usage has always been more reliable than the ordinary preferences, I don’t either. ¦ Reisio (talk) 09:09, 8 April 2013 (UTC)

Thanks, Reisio. In about:config, browser.showQuitWarning seems to have the desired effect. With that set to true, command-Q now pops up the dialog I had in mind, asking "Do you want Firefox to save your tabs and windows for the next time it starts?" and offering 'Quit', 'Cancel', and 'Save and Quit' buttons.

Dismas: I don't know why I have to go into an advanced, warranty-voiding configuration screen to achieve this functionality, either, but on this version of Firefox (5.01 on a Mac), the checkbox you mentioned under "Preferences > Tabs > Warn me before closing multiple tabs" seems only to affect the behavior when closing a window containing multiple tabs, not when quitting a session containing multiple windows or tabs. —Steve Summit (talk) 10:25, 8 April 2013 (UTC)

There is of course no warranty to void. :p They haven’t changed how about:config works in ages, so again, more reliable. ¦ Reisio (talk) 15:39, 8 April 2013 (UTC)

Also note that you can do History->Recently Closed Windows to get a bunch of old tabs back. --Sean 15:43, 9 April 2013 (UTC)

USB sound card

With an external USB sound card, does sound that would normally go to the 3.5mm speaker jacks go to the USB sound card? Bubba73 ^{You talkin' to me?} 03:41, 8 April 2013 (UTC)

If it has its own input & output, you can no doubt use those, but with the right software you should be able to use whatever audio input & output you please, too. ¦ Reisio (talk) 05:06, 8 April 2013 (UTC)

The one I'm considering has a USB input. If I play iTunes, YouTube, a website, or other sound files, the sound would normally go to the 3.5mm speaker jacks. The card should have software that would make these things go to it instead, over the USB input? Bubba73 ^{You talkin' to me?} 05:16, 8 April 2013 (UTC)

If you mean the “card” is a USB dongle that resembles a USB stick but is an audio device instead of a storage device, without audio jacks of its own, obviously it (or rather the audio output it produces) would depend on the computer’s existing audio jacks. This is how most such things work, to my understanding. There’s no particular reason a USB device can’t work just like a PCI card. OS sees hardware, OS utilizes hardware.
If you can link to or otherwise specify the particular device you’re talking about, a lot more could be explained more clearly. ¦ Reisio (talk) 05:26, 8 April 2013 (UTC)

There's no way to send analog audio over USB or PCI. PCI sound cards either have audio jacks on them or have to be separately wired to the audio jacks. -- BenRG 05:51, 8 April 2013 (UTC)

Ok, this card I should be able to just put it in a slot and the sound that would normally go to the speakers would go to its phono jacks, I think. But I'd rather have one like this, if it will work as I want. It plugs into USB, has phono jack outputs and a headphone output with a volume control. I would like for the computer sound to go to it. Bubba73 ^{You talkin' to me?} 05:36, 8 April 2013 (UTC)

The USB sound card should show up as an additional audio device. Many audio players allow you to choose a non-default output device, and if not, you can set it as the default. -- BenRG 05:51, 8 April 2013 (UTC)

Thank you

Resolved

Bubba73 ^{You talkin' to me?} 20:21, 8 April 2013 (UTC)

How do we make a GIF?

Am I the only one around here who doesn't know how? (Particularly, the moving gifs?)

Also, what are the time-limits to how much footage can be put in a gif?

Moreover, if I decide to print it out physically, what frame will show on said print-out? (Beginning? Middle? End?) Thanks. --129.130.237.131 (talk) 04:20, 8 April 2013 (UTC)

It's pretty easy to create an animated GIF using GIMP -- you just have to create a multi-layer image and then save it in the right way, and each layer becomes a frame. There is no time limit in principle, but each frame increases the memory size of the GIF file. The results of printing one depend on which print utility you use. In most cases you just see the first frame. Looie496 (talk) 04:43, 8 April 2013 (UTC)

I found this it seems to be a very easy to use software. Just saying, there is no time limit but it is best not to exceed say 20 frames (but thats just my opinion). This is also because the more frames means bigger file sizes (and if your going to upload it onto a website they usually have size limits).  RunningUranium  07:11, 8 April 2013 (UTC)

To clarify, do you want to create animated GIFs from a utility, like GIMP, or from a program you write ? If you want help with the later, I can make some suggestions. (See the bottom of my home page for some animated GIFs I created with my own program.) One limitation to keep in mind is that each frame of an animated GIF can only have 256 colors. This pretty much eliminates full color shading, but you can do 2-color shading (like red to blue). StuRat (talk) 02:52, 9 April 2013 (UTC)

The other two questions you asked:- No you were not the only one who doesn't know how. ;-) And for a gif displayed without a special player the first frame is the one printed or displayed if there is no animation - the format itself does not support any standard way of specifying any other frame. Dmcq (talk) 09:11, 9 April 2013 (UTC)

Terminology for error-message reduction

Many years ago, when mainframe computers became commonplace, there was a "programming paradigm" for end-user documentation to list a complete set of so-called "error messages" which were typically listed in a document explaining the meaning of each error message, often coded with an error-message id number. However, I am looking for a term that means programming in a style of "error-message reduction" where invalid data is just echoed back to the user, rather than flagged with a numbered error message. For example, in writing a span-tag:

• Old style result: <spann xx> <--ERROR G45-H78P: Unrecognized keyword "spann" at line 345 column 27
• New style result: <spann xx>

In the newer style of programming, it just echoes back the invalid input text, "<spann xx>" when an unrecognized keyword "spann" is used in the markup language, and there is no error message displayed, and no error id number, and no document to list all error messages. Sometimes that is easier, but sometimes the lack of error messages can be confusing. Question: what is that programming paradigm called, to not show a bunch of error messages, but only echo back the data, when a problem is detected? -Wikid77 (talk) 07:49, 8 April 2013 (UTC)

“Bad programming”. ¦ Reisio (talk) 15:42, 8 April 2013 (UTC)

Firefox crashes more unexpectedly than before

I run Firefox (latest version, it upgrades automatically) on a Windows XP computer. I have had problems for years with Firefox either crashing or freezing (and necessitating me to do a forced close through the Task Manager) when it is doing something: when I try to open a webpage with lots of content, especially scripts or media, or when I try to close one or many tabs or pages.

Lately, I have had the problem with Firefox just quitting unexpectedly without any such obvious cause (and no signs of previous distress such as slowing down) when I'm not really doing anything except reading content on an already open page. Is this something others have experienced with later versions of Firefox, or is it just that my computer is getting old or needs more memory? --Hegvald (talk) 10:21, 8 April 2013 (UTC)

I think it’s probably more that your computer is getting old and needs more memory (and that its OS/version is incredibly out of date and more insecure than ever). ¦ Reisio (talk) 15:41, 8 April 2013 (UTC)

Up until a month ago, I used to use Firefox 1.5 on an XP machine from 2006 (2 GhZ, 1 GB of RAM) for nearly all my browsing as I preferred it over later versions, with Firefox 12.0 also installed to support any pages that 1.5 didn't (e.g., HTML5). (I upgraded my machine because of increasing gaming/video speed/lag issues with my seven-year-old hardware, not anything else. And Reisio, I never had any issues with XP itself or insecurity -- only hardware issues.) I noticed that 1.5 would freeze on certain pages as well, especially ones with Javascript. I kept Javascript disabled by default, used a plugin called Keyconfig (hotkey configuring plugin) to re-enable and disable Javascript at the touch of a button for pages that needed it, and my problems disappeared. (In fact, the site that led me to do this was Wikipedia -- the internal design changed to include something that froze Firefox for ~10 seconds when loading anything, until I disabled Javascript.) -- 143.85.199.242 (talk) 16:01, 8 April 2013 (UTC)

Try to disable all add-ons and see what happens. Many of them are not compatible with the latest version. OsmanRF34 (talk) 16:25, 8 April 2013 (UTC)

I agree that something happened with Firefox (on XP) in the last month or so. It is often very slow or even freezes completely. However in past few days it caused several BSoDs! And this happened on the machine that could work for weeks without needing a restart. Ruslik_Zero 19:20, 8 April 2013 (UTC)

Here's another piece of unreferenced advice for you, a little more specific than what OsmanRF34 suggested: when FF freezes, bring up Task Manager and kill the "plugin-container" task. The desired response is:

• All flash animations crash and are replaced with a grey box,
• Each box says "The Adobe Flash Player has crashed" or equivalent text, and
• Firefox starts scrolling, responding, etc again.

If that's what happens for you, then Flash is the problem, not Firefox. Good luck -- but if this doesn't work, you're back to Osman's suggestions.

--DaHorsesMouth (talk) 23:35, 8 April 2013 (UTC)

Firewalls in Linux

Is there a firewall in Linux which would let me block or allow applications? (instead of port or protocols).OsmanRF34 (talk) 15:59, 8 April 2013 (UTC)

It looks like iptables can do it if your kernel supports the feature.

From the man page: "--cmd-owner name

Matches if the packet was created by a process with the given command name. (this option is present only if iptables was compiled under a kernel supporting this feature)" 38.111.64.107 (talk) 17:39, 8 April 2013 (UTC)

Flashing "cursor" static

I have a new ASUS computer with which I am generally impressed. But when I am on a static backgound (i.e., a white or black backgrond that is not animated or otherwise changing) I see what looks like an underline (i.e., _ ) cursor randomly flashing around the screen, appearing just long enough to be consciously visible (maybe 1/20th of a second) in black on white backgrounds, or white on dark backgrounds, maybe 5-10 times a second as I notice it. I see it now as I am typing in the edit box. I see it when I am reading the FBI/Interpol warning on copyrighted movies. I don't see it during the movie, on my desktop, or when there is some sort of moving picture like a dvd or a youtube clip playing. Can anyone suggest what this might be called, what might cause it, and where I can go for advice on how to fix it? Thanks. μηδείς (talk) 20:23, 8 April 2013 (UTC)

Maybe that's a dead pixel? Your guarantee should cover that. OsmanRF34 (talk) 20:28, 8 April 2013 (UTC)

No, it flashes all over the screen, white on dark backgrounds and black on light backgrounds, very much like analog TV static, although in the shape of _ and one at a time so far as I have noticed. μηδείς (talk) 21:14, 8 April 2013 (UTC)

A dancing hyphen blitting around the screen! I've worked as a graphics engineer for a long time, and although I have never seen your make-and-model system, I know exactly what symptom you're talking about. This symptom is very frequently a characteristic of a bandwidth-starved DMA from a graphics device into a frame buffer. That symptom will occur if the total system load is just a notch too high for the system's capabilities; and it manifests as a nearly non-deterministic data-error at very low rate. (Therefore, the hyphen or hyphens - a few consecutive pixels in a row - appear in "totally random" locations). It may sometimes be solved by re-calibrating or re-tuning software priorities; (this is something the manufacturer or its engineering staff will do); so as an end-user, you would need to wait for a new driver update or firmware release. In some cases, it is a hardware performance limitation and cannot be solved through software-update. In modern systems, it is not easy to determine when or why a DMA accelerator may become bandwidth-starved; if the root-cause were obvious or solvable through naive methods, the engineers would have already fixed it before shipping your system. Monitor the manufacturer's website for software- and driver- updates. Nimur (talk) 21:24, 8 April 2013 (UTC)

Yes, I figured this had to be some sort of processing issue, since it doesn't appear at all times. But it is a top end computer, i7 quad core 16 GB RAM, nvidia gforce gtx.... Is it possible that there's some software that I have now that I can uninstall that might help, or is it possible there's some update available now that I might look for? Thanks. μηδείς (talk) 21:41, 8 April 2013 (UTC)

I wonder if a different resolution (which could have a different refresh rate) would work better here. Maybe the top resolution looks good, but doesn't work for all users, so they didn't catch the problem. So, choose another resolution and see what happens. OsmanRF34 (talk) 21:38, 8 April 2013 (UTC)

I lowered the res to 1600/900 and the problem seems to have gotten better, but not gone away. In fact, the less frequent blinking seems more distracting, as I type! μηδείς (talk) 21:46, 8 April 2013 (UTC)

Checked for new drivers? [[2]]

I wonder if connecting to the monitor with a different type of cable might help. That is, HDMI versus D-sub, etc. StuRat (talk) 02:46, 9 April 2013 (UTC)

It's a laptop. μηδείς (talk) 03:08, 9 April 2013 (UTC)

Try an external monitor then, if only to help isolate the problem. StuRat (talk) 03:16, 9 April 2013 (UTC)

If it is new I'd contact the manufacturer about fixing or replacement. Dmcq (talk) 08:53, 9 April 2013 (UTC)

The 'other' Google employees

Are Google's perks for all its employees or only for a selected group of developers? Is working for Google as accountant, client manager, janitor or whatever much different than in other companies? OsmanRF34 (talk) 20:26, 8 April 2013 (UTC)

For all employees. But crucially many services in a typical Silicon Valley company are outsourced to contractors, whose employees thus aren't employees of that company and so don't get its benefits (they get whatever benefits their own employer has). So you'd expect security, janitorial, property-services, landscaping, and folks like that to work for some outside company that specialises in that specific task. White-collar services like recruiting, accountancy, HR, payroll, and legal will often be split with some folks in-house and others working for another company. -- Finlay McWalterჷTalk 20:35, 8 April 2013 (UTC)

April 9

Does mining for bitcoins count as a server?

I am interested in joining a pooled group of users to mine for bitcoins with a secondary computer that I would like to set aside solely for this purpose. I am on a US university campus internet system. Our policy states that we are not allowed to connect a server to the school internet system (to prevent bandwidth hogging I'm assuming). Does mining for bitcoins count as using my computer as a server? Does it hog large amounts of internet bandwidth relative to using a computer for more "normal" usages? Acceptable (talk) 00:14, 9 April 2013 (UTC)

You're basically trying to use the university's facilities for a private moneymaking (literally!) enterprise, and I don't think we ought to advise you on the legalities of that. Looie496 (talk) 03:50, 9 April 2013 (UTC)

That's not the question the OP is asking though; it is a technical one, not a legal one. Even in terms of "legalities," this is less a matter of the law per se than it is the university's IT policies. (There is no law against making money at university; there are sometimes internal policies regulating it.) --Mr.98 (talk) 13:04, 9 April 2013 (UTC)

My understanding of Bitcoin pooling is not great, but from what I can tell, it seems to involve:

• Downloading a little bit of information
• Processing that information
• Uploading a little bit of information when you're done

If the above is true, then none of that ought to use very much bandwidth, and none of which ought to count as a being a server. And today, "normal" usage means things like streaming movies or music, which take huge amounts of bandwidth by comparison. But if you are really concerned about violating your university IT policies you should contact them. --Mr.98 (talk) 13:04, 9 April 2013 (UTC)

"Server" is a bit og a loose term in IT today. However barring any clear indications otherwise I would interpret it to mean a machine or process that waits for and acts on "requests" that originates "elsewhere". Mining for bitcoins will not match that definition if you are just operation alone. If you are part of a mining pool then it depens a bit more on how the programs are set up, but in that case it's quite possible that you will be running a server. Taemyr (talk) 12:29, 10 April 2013 (UTC)

Word 2007 - Headers & Footers

I have a document for translation, and the original has headers and footers on each page, which also need to be translated. Normally, this would not be a problem, but it appears that on the first page only, there is a title above the header. This title is not part of the header, nor does this title appear on any other page. How is it possible for me to add this title in above the header, and only on this one page, so that when I move onto the second page, the header for the second page will be at the top, with nothing above it? KägeTorä - (影虎) (TALK) 08:11, 9 April 2013 (UTC)

You can have a unique header for the first page only (demo). So on that first page, you'd duplicate the normal header, and then add in the additional matter at the top of the header. -- Finlay McWalterჷTalk 08:29, 9 April 2013 (UTC)

Ｔｈａｎｋｓ！　Ｊｕｓｔ　ｗｈａｔ　Ｉ　ｎｅｅｄ．--KägeTorä - (影虎) (TALK) 11:04, 9 April 2013 (UTC)

Router: current UK pronunciations?

Hi folks. I'm retired from editing WP, and am here as a consumer. Posting at the computing desk rather than the language desk because I want accurate answers from real UK speakers of computer jargon, not from "official" sources.

How is "router" (the computer term, not the woodworking term with the different etymology) pronounced in the UK? I had assumed that it would rhyme with "doubter" (as in the US, and here in Australia), not with "looter"; but I have checked several British dictionaries, and they want it to rhyme with "looter".

So, actual UK geeks: how do you say it? (₰?) Many thanks.

Noetica^Tea? 11:21, 9 April 2013 (UTC)

In this episode of Channel 5's The Gadget Show, Jason Bradbury and Ortis Deley both pronounce it like "looter". -- Finlay McWalterჷTalk 11:33, 9 April 2013 (UTC)

In the episode of the BBC's Click from the 30th of March (it's off iPlayer, but you'll find it on YouTube), reporter Dan Simmons says it like "looter" too (2 minutes 40 in). -- Finlay McWalterჷTalk 11:39, 9 April 2013 (UTC)

And as a British IT pro I can personally confirm (is OR OK this once?) that that's how we say it. For the record, we also pronounce "route" the same as "root". Rojomoke (talk) 12:13, 9 April 2013 (UTC)

Yup, it's a 'Rooter' - which helps us distinguish it from a 'Rowter', or, as Handy Andy would say, a raah'er. - Cucumber Mike (talk) 12:35, 9 April 2013 (UTC)

"Rooter" :) --Gilderien Chat|List of good deeds 12:47, 9 April 2013 (UTC)

Plenty of people in the USA pronounce it “rooter” as well, though probably a minority. “route” (as in a road) is frequently pronounced “root”. ¦ Reisio (talk) 18:14, 9 April 2013 (UTC)

As in Route 66, for example. AndrewWTaylor (talk) 18:51, 9 April 2013 (UTC)

I'll confirm, you're in the minority in the U.S. if you pronounce it that way. Shadowjams (talk) 21:37, 9 April 2013 (UTC)

Not sure you’re an authority :p but it wouldn’t surprise me. ¦ Reisio (talk) 05:16, 10 April 2013 (UTC)

I am grateful for the information, guys. Seems the dictionaries have it right. In Australia we are generally aware of British and American differences, and of where our own pronunciation and vocabulary choices fit on the linguistic map. But there are exceptions. Here's what I think now: Normally, we would follow the British norm for such a word. We, like the Brits, say "root" for the well-established word "route", of course. But the computer term "router" is a newcomer, and we take advantage of its general Americanness and its novelty to avoid an awkward echo of "root" meaning "fuck" (both noun and verb). That is very coarse old Australian; so we prefer the American pronunciation almost exclusively. On the other hand, this would not explain our pronunciation of "cache" the American way: "caysh", not "cash" or "cahsh". Hmmm.
Noetica^Tea? 09:30, 10 April 2013 (UTC)

Not really following this last. I have never heard any pronunciation other than "cash" in the States (I guess you mean /kæʃ/ for "cash"). What you mean by "caysh" I'm not really sure; could be either /kaɪʃ/ or /keɪʃ/, but in either case it would sound very odd to Americans as a pronunciation of "cache". --Trovatore (talk) 01:09, 11 April 2013 (UTC)

Thanks, Trovatore. A few points: As I say, I posted here and not at the language desk because I want actual usage from computer specialists (and incidentally, because I have retired from editing and want to stay away from my usual haunts). I avoided IPA, for the convenience of non-linguists. By the naive form "caysh" I intend /keɪʃ/, of course. No native speaker without linguistics exposure is likely to take it as /kaɪʃ/, especially since I also used the crass naive form "cahsh" nearby. Now, I was mistaken about the dominant US pronunciation, which prompted by you I have since checked. I knew that British usage avoids /keɪʃ/ (OED: "/kæʃ/, formerly also /kɑːʃ/"; other sources agree). But I did not know that /keɪʃ/ was mostly confined to Australia. I don't know where we got it! I remember my own surprise, decades ago, being "corrected" by a highly literate Australian editor and computer expert: /keɪʃ/, he insisted.

I edit professionally to both British and US norms, and am well versed in the differences on the page: lexical, syntactical, morphological, and all the rest. But as I say, we can still get certain "foreign" pronunciations wrong, for terms that are mostly confined to written texts unless they are spoken locally. Like "router", and also "cache". Hence my enquiries.

See here for quite diverse opinions on the case of "cache"; and here for a sample of opinions from tech-savvy Ozfolk.

Noetica^Tea? 05:28, 11 April 2013 (UTC)

Compatibility of add-ons/extensions/plug-ins across browsers

If they are in javascript, shouldn't that be the case? However, you normally get browser specific add-ons offered. Why is it like that? OsmanRF34 (talk) 13:17, 9 April 2013 (UTC)

Basically, if a plugin is written in Javascript (which not all are!), it requires an environment to run in. Each browser has its own way of making plugin environments for the Javascript. You can't just take raw Javascript and have it act as a plugin. (You can run it on a webpage, but that's not the same thing.) Because there is no universal plugin environment, each browser handles it somewhat differently, and thus each plugin needs to be written for the specifics of each browser. Basically. --Mr.98 (talk) 15:15, 9 April 2013 (UTC)

external HD SMART results

Above I was talking about problems with making a Carbonite mirror image to an external HD. I thought they were saying that my internal HD was having problems. It looked OK under HDTune. I ran it on all my drives (2 internal, 4 external) and the external HD I was making the mirror image to gave some strange results:

HD Tune Pro: Seagate GoFlex Desk      Health

ID                                  Current  Worst    ThresholdData         Status   
(01) Raw Read Error Rate            119      99       6        223195006    ok       
(03) Spin Up Time                   89       89       0        0            ok       
(04) Start/Stop Count               98       98       20       2791         ok       
(05) Reallocated Sector Count       100      100      36       0            ok   *    
(07) Seek Error Rate                77       60       30       55977040     ok       
(09) Power On Hours Count           90       90       0        9035         ok       
(0A) Spin Retry Count               100      100      97       0            ok   *   
(0C) Power Cycle Count              100      100      20       94           ok       
(B7) (unknown attribute)            1        1        0        119          ok       
(B8) End To End Error Detection     100      100      99       0            ok   *
(BB) Reported Uncorrectable Errors  100      100      0        0            ok       
(BC) Command Timeout                100      84       0        12386497     ok   *    
(BD) (unknown attribute)            100      100      0        0            ok       
(BE) Airflow Temperature            33       28       45       1127809091   ok       
(BF) G-sense Error Rate             100      100      0        0            ok       
(C0) Unsafe Shutdown Count          100      100      0        25           ok       
(C1) Load Cycle Count               99       99       0        2930         ok       
(C2) Temperature                    67       72       0        67           ok       
(C3) Hardware ECC Recovered         23       4        0        223195006    ok       
(C5) Current Pending Sector         100      100      0        0            ok   *  
(C6) Offline Uncorrectable          100      100      0        0            ok   *
(C7) Ultra DMA CRC Error Count      200      200      0        0            ok       
(F0) Head Flying Hours              100      253      0        2565         ok       
(F1) LifeTime Writes from Host      100      253      0        -1605911949  ok       
(F2) LifeTime Reads from Host       100      253      0        -794413361   ok       

Health Status         : n/a

I put * by the ones that the SMART article says are crucial. Look at the (BC) Command Timeout. On my other drives, this is 0-5. On this one it is over 12 million. Also, it is running hot at 67C (others are in the 35-47 range, and I've read that 55 or so is too hot). Right now I've got it unplugged to let it cool off. So does it look like this drive is having a problem? Bubba73 ^{You talkin' to me?} 14:36, 9 April 2013 (UTC)

Phone

How do you get room to work on a windows phone 7.8? --80.161.143.239 (talk) 15:15, 9 April 2013 (UTC)

Windows v. Unix Copy

I'm working in a mixed environment of windows and Unix machines, with a Samba server making the Unix files visible to the Windows clients. I've been told that I must use the Unix command line interface to copy Unix binaries between directories, as dragging and dropping them in Windows may result in the files getting corrupted.
Is this true? Is Windows really incapable of copying a binary file from one location to another? Is Samba the culprit? I assume .exe files and others that Windows realises are binaries are somehow protected? Rojomoke (talk) 16:18, 9 April 2013 (UTC)

Copying files is rather hard, really. And doing so when calls are mediated through a foreign interface like Samba makes it harder. It's tempting to think copying a file is a matter of reading blocks of data from one file to another. And mostly this works just fine. But files are more than bytestreams, and handling them in a way that treats them as if they were risks some weird cases where the result isn't what a someone might expect. On Unix a file has, or can have, metadata, ACLs, extended file attributes and may be sparse, a symlink, or a hardlink. On Windows, NTFS files can have ACLs too (but a different kind). On Mac files can (but usually don't, now) have resource forks and on Windows (also, luckily, rarely) alternate data streams. Fancier modern file systems like Btrfs can implement copy-on-write. Sometimes you want to copy this stuff, sometimes you don't, and sometimes you want a choice. So rather than read-then-write, you really want a pre-written utility that's aware of all this scary stuff and just does "the right thing". Windows has library calls for this (CopyFile and CopyFileEx) as does OS-X (copyfile(3)). POSIX does not, and neither (as far as I know) does Linux or glibc (Linux has the rather basic sendfile(2) kernel call); see this entertaining LKML discussion about adding such a call; it mostly concludes "sendfile does some of it, we don't want to reimplement all of cp in the kernel, and it's lots of work so you go do it". Perhaps the safest thing is to call cp iself, which has tons of horrid special-case code to worry about this stuff. But it practice most of the above is super-rare, and lots of people just do read-then-write followed by some ioctls to set attributes (I just checked the source of Python3's shutil.copyfile, and that's what it does). I don't know what Samba does - the folks who write it are exceptionally smart, but given all the complexities above, it's very possible they couldn't think of a "clever" solution, and just did the obvious thing. It may simply be that those issuing the edict in question got burned once (in some hard to diagnose way) because some version of Samba didn't do things in a way they'd expected (on a file they didn't know was special). -- Finlay McWalterჷTalk 17:28, 9 April 2013 (UTC)

not familiar with samba, but depending on the configurations of the unix and windows networks and their connection with each other, it might be a huge load on the windows network to move giant files around when the unix network can handle them without breaking a sweat. (that, I have had experience with) Gzuckier (talk) 19:16, 9 April 2013 (UTC)

That's an excellent point... if you're moving a file on samba share A to samba share B, your local machine will do all the io on that (I'm pretty sure this is what's going on with my own network...). Samba has a lot of consideration for filesystem idiosyncrasies. The way it handles case-sensitivity has been brought up on this desk before, and it's more complicated than you'd think at first glance. The filelocking/atomic question is some low level stuff that Finlay explained nicely. A relevant follow up question is how many people are accessing these files at the same time, and how big are the pipes between them, etc. Some knowledge of the environment would probably shed some light on the impetus for the rule. The other thought I had that's not mentioned yet, is perhaps they're concerned about file permissions being consistent. There are lots of ways to handle this with samba (and I don't mean the complicated ACL stuff Finlay mentioned), but sometimes it's just easier to make a rule. Shadowjams (talk) 21:35, 9 April 2013 (UTC)

Free software to upscale images in bulk?

What's a good program to upscale a large quantity of images? By "upscale", I mean to increase the dimensions of a given file to a specified size. Quality degradation is not too terribly important, and I'm looking for a free (as in beer) program to do this, ideally without some silly watermark. Any suggestions? -71.37.142.66 (talk) 17:22, 9 April 2013 (UTC)

Imagemagick - docs -- Finlay McWalterჷTalk 17:29, 9 April 2013 (UTC)

Thank you! - 71.37.142.66 (talk) 17:33, 9 April 2013 (UTC)

Just in case you don't know, this isn't a very good idea, in general. You are increasing the file size without increasing the actual resolution. This is the opposite of the normal goal, to pack as much information as possible into a minimal space. If you need to display the image at a larger size, many display programs can do that without permanently increasing the file size. StuRat (talk) 03:52, 10 April 2013 (UTC)

golden ax

how can i win golden ax, what are best tricks techniqes, what surprises are there and wich is the best character, is t best to run and leep or to stand and fight and when is best to use magic? on megadrive Horatio Snickers (talk) 20:40, 9 April 2013 (UTC)

Here you go. Tarcil (talk) 21:17, 9 April 2013 (UTC)

April 10

External HD hot and not spinning down

One of my four external drives is hot and not spinning down when not in use. Utilities that read S.M.A.R.T. data show it at 67-72C at various times, which is too hot. The others spin down, but not this one. Is there a way to tell it to spin down when not in use? Bubba73 ^{You talkin' to me?} 02:58, 10 April 2013 (UTC)

If you don’t mind all your disks spinning down after the same interval of not being used, you can try using Windows’ own power options. Otherwise, you might have to rely on random third party apps.[3][4] ¦ Reisio (talk) 03:16, 10 April 2013 (UTC)

I don't want the internal drives spinning down. That temperature is cause for concern, isn't it? Bubba73 ^{You talkin' to me?} 03:31, 10 April 2013 (UTC)

Yes, I think so. You can always remove the case and point a fan at it, then unplug the HD when not in use. Not an elegant solution, but it should keep it alive at least long enough to copy anything vital off it. StuRat (talk) 03:38, 10 April 2013 (UTC)

Of the two links you gave, the HDDScan zip file doesn't have an executable file in it. HotSwap starts up but doesn't do anything. Bubba73 ^{You talkin' to me?} 03:44, 10 April 2013 (UTC)

You could try sdparm or hdparm. ¦ Reisio (talk) 03:48, 10 April 2013 (UTC)

I contacted Seagate tech support. Bubba73 ^{You talkin' to me?} 04:46, 10 April 2013 (UTC)

I contacted Seagate a few months ago to RMA a dying disk within its warranty period. The whole process went like this:

• I raised the ticket
• They asked me to run their own SMART utility (because they don't trust third party tools)
• That reported the same scary SMART data that other utilities already had (the disk had thousands of 0x05 reallocations)
• They emailed me an RMA label. I had to package the thing myself and post it, at my expense, to their facility (which for Europe is adjacent to Schipol Airport)
• Because the disk still had data on it, I bought a new disk, dd copied the dying disk to it, and the dd blanked the bad one. The trouble with modern disks is that they're so gigantic that those dd operations took about 11 hours.
• On receipt, they confirmed the disk was indeed bad, and mailed me a reconditioned one of the same specification as the previous one. I think it took about 11 days from my sending the bad to receiving the good. They didn't reimburse me for the postage sending the bad drive.

-- Finlay McWalterჷTalk 10:45, 10 April 2013 (UTC)

BTW, this is the external drive that I was making the Carbonite mirror image to (see problems above). But Carbonite said that the external drive was not the problem. (However, it might be.) Bubba73 ^{You talkin' to me?} 03:46, 10 April 2013 (UTC)

The temperature would be a cause of concern if it's correct. While I haven't used that many external HDs, I have my doubts whether it is. That's a very high temperature for a HD even locked up on a sealed case with no airflow I have doubts it's likely to get that high unless perhaps your ambient temperature is 50 degrees C. It could easily be either a defective sensor or buggy software or firmware. Unfortunately since it's external I presume you can't open it up to feel the HD casing (while the sensor is internal, if it was really that high you should feel it to some extent as the temperature differential shouldn't be that high). What is the temperature reported when just powered up after being off for a long time? Edit: However I have found some other reports [5] of similar temperatures although again it's unclear if the temperatures are correct. (The statement by the user that the transfer rate had dropped from 100MB/s to 60MB/s after about an hour doesn't exactly inspire confidence that they know what they're talking about. The transfer rate drop almost definitely has nothing to do with the temperature but the fact that the middle of the HD is slower then the beginning. In addition, it doesn't sound like they understood the importance of backups.) Nil Einne (talk) 05:56, 10 April 2013 (UTC)

Two separate programs reported those high temperatures and I could feel that it was hotter than the others. I could also feel that it was running and not spinning down. Seagate tech support told me how to set it to spin down using their software. It was set to spin down after 15 minutes of inactivity, but it wasn't doing it. I changed it to 3 minutes and it is doing it. Now it is showing 47C. Bubba73 ^{You talkin' to me?} 15:35, 10 April 2013 (UTC)

Good. Those symptoms make me think that there is just some disk activity every 10 minutes or so, causing it to never hit the 15 minute threshold. This would be most likely if this is the drive containing the active operating system. However, that temp seems too high even when it is running, so I think you've just found a workaround, not actually fixed the problem. I'd still want to remove the case to limit heat damage. StuRat (talk) 15:59, 10 April 2013 (UTC)

Right now CrystalDiskInfo is showing it at 46C and my other external drives at 44C, so that seems OK. The internal drives are cooler, at 35 & 38C. I think somewhere around 53-55C is considered too hot. Bubba73 ^{You talkin' to me?} 16:17, 10 April 2013 (UTC)

Yes, but if you start using the drive, say to copy lots of files, I bet it will heat up to the danger zone again. StuRat (talk) 16:48, 10 April 2013 (UTC)

Yes, something isn't right. I set it to spin down, and that did work. But later I noticed that it was spinning again. After about a half hour of inactivity, it is still spinning and now the temp is up to 54C and in the yellow zone. I'm going to try to track it down and see if it is something wrong with the drive or something about using it for the Carbonite mirror image, although I've had that turned off since yesterday. Bubba73 ^{You talkin' to me?} 17:33, 10 April 2013 (UTC)

Resolved

some sort of indexing for windows or another search function? Gzuckier (talk) 18:55, 10 April 2013 (UTC)

Possibly, but I have indexing off except for my C drive. I believe the drive is defective. I have another Seagate external, and running it continuously gets it no hotter than 45C. Bubba73 ^{You talkin' to me?} 19:20, 10 April 2013 (UTC)

Why didn't Google's Street View service cover all streets in Kansas like they did in so many other states?

Look here, there are only 2 or 3 streets in Concordia, Kansas that Street View covers. However, in many other places in the US, all streets are.

Why did Google's Street View fleet get neglectful in Kansas?

Moreover, was that a one-time project or will they send out another fleet of Street View cars in order to cover the roads that they didn't the first time? Is there any way to know whether they will come around Kansas again to map the streets that they didn't earlier? Thanks. --70.179.161.230 (talk) 07:12, 10 April 2013 (UTC)

[[6]] has the answer. It doesn't cover all the US yet. OsmanRF34 (talk) 11:45, 10 April 2013 (UTC)

They probably prioritized places people would be more likely to actually want a street view of. I know they’ve been by my own house two or three times over the years already, though, so it doesn’t really make complete sense that they haven’t been by all those. I imagine that’s all contract work, though, so however much interest/personnel are available for it in whatever location is probably a factor. They could also already have all the data but for whatever reason haven’t incorporated it yet. ¦ Reisio (talk) 14:44, 10 April 2013 (UTC)

Optical disc drive no longer reads DVDs of any kind but can still read CDs

I have a Windows XP computer with an internal optical disc drive (it's a DVD-RAM drive made by LG). Up until very recently, it was able to read and write to both CDs and DVDs, but I noticed yesterday that it is no longer able to read DVD media of any kind (video or data). It can still read CDs, but after a DVD has been inserted (and removed) it is no longer able to read a CD until the computer is restarted (which seems odd if it's a hardware problem).

Should I just buy a new disc drive or is this behaviour potentially linked to a software problem? The drive in question is at least five years old at this point and new drives are cheap, but I'd rather not throw the old drive away unless necessary. Any comments would be appreciated. 142.20.133.199 (talk) 13:43, 10 April 2013 (UTC)

If you can boot from USB (or another CD/DVD drive on the same box), you could boot up a live OS and try to play with the drive in question, potentially ruling out a hardware issue (or confirming one). ¦ Reisio (talk) 15:03, 10 April 2013 (UTC)

It could very well be a hardware issue, since bits are more closely packed on a DVD than a CD. Therefore, if it's accuracy is off a little bit, it will miss the DVD bits, but still find the CD bits. You might try a CD cleaner, in case some schmutz on the read head is the problem. StuRat (talk) 17:42, 10 April 2013 (UTC)

CD and DVD drives use different laser diodes. Probably the laser diode that is needed to read/write DVDs stopped working. Ruslik_Zero 18:52, 10 April 2013 (UTC)

Virus causing password requirement?

Is there a virus that affects Windows 7 that causes the computer to require an administrative password to start it? (It's my computer-illiterate mother's computer, not mine, mind you, so "lrn2linux" comments to /dev/null.) If so, and if it changes the admin password, what would it change it to? —Jeremy v^_^v ^Bori! 18:38, 10 April 2013 (UTC)

It may be Ransomware (malware). -- Finlay McWalterჷTalk 18:51, 10 April 2013 (UTC)

It isn't giving a number or any other means to contact. All it's doing is asking for a password to boot into Windows. —Jeremy v^_^v ^Bori! 18:52, 10 April 2013 (UTC)

Isn't that the usual behavior of Windows 7? Could you give a clearer description of exactly what you are seeing? Looie496 (talk) 18:59, 10 April 2013 (UTC)

When one attempts to boot up, a window pops up which indicates that a password is needed to finish booting up the OS. (i.e. it doesn't go into the login screen.) As my mother is computer illiterate, this isn't something she would have been able to set up herself. It gives you three attempts at the password before it restarts. —Jeremy v^_^v ^Bori! 19:01, 10 April 2013 (UTC)

Could you say what model of computer it is, and the exact wording of the text you see? I'm trying to figure out whether this is a BIOS password or something else. Looie496 (talk) 19:21, 10 April 2013 (UTC)

It is a Dell Inspiron desktop (model number escapes me), and the text of the box is "This computer is configured to require a password in order to start up. Enter the Startup Password below." —Jeremy v^_^v ^Bori! 19:25, 10 April 2013 (UTC)

On a similar note, the administrator password is not set up in the BIOS, so it's not BIOS-related. —Jeremy v^_^v ^Bori! 19:33, 10 April 2013 (UTC)

A search for those messages shows nothing relating to Windows 7 but numerous reports involving Windows XP. Apparently it is possible to set up XP to require a System Password, but there is also malware that does it. If it is malware, probably the only solution is to restore the system. Looie496 (talk) 19:54, 10 April 2013 (UTC)

Okay, and how would I go about doing that if I can't even access the operating system? —Jeremy v^_^v ^Bori! 19:58, 10 April 2013 (UTC)

You need to have a disk you can boot from. If you don't have a system restore disk, things become challenging. Is this actually perhaps XP, by the way? Looie496 (talk) 20:02, 10 April 2013 (UTC)

No, it's Win7. Not XP. —Jeremy v^_^v ^Bori! 20:05, 10 April 2013 (UTC)

You may need to take it to an electronics place like Best Buy or something similar, where they will have boot disks, if you don't have one, and reset the password. RNealK (talk) 22:24, 10 April 2013 (UTC)

Downgrading Windows 7 from 64-bit to 32-bit

As far as I can tell, 64-bit Windows 7 does nothing useful for me, and just hogs a lot of memory. So, if I wanted to switch back to 32-bit, would I have to uninstall and reinstall the O/S, then reinstall every app for it ? Or can I just set a flag somewhere to have to work in 32-bit mode ? StuRat (talk) 18:55, 10 April 2013 (UTC)

You’d have to reinstall. I suggest you don’t (unless to switch to a better OS! :p). ¦ Reisio (talk) 19:07, 10 April 2013 (UTC)

I wouldn't do it either. The 64-bit Windows manages your memory better, for one thing. For instance, if you have 4GB of RAM, I think 32-bit Windows only has access to 3 to 3.5GB of it whereas 64-bit Windows gets all of it. Someone correct me if I'm wrong. (And some software functions better in the 64-bit version.) Bubba73 ^{You talkin' to me?} 19:15, 10 April 2013 (UTC)

Yes, but I only have 2GB of RAM, and it seems pegged out near 100% all the time under 64-bit mode, while that should be plenty for 32-bit.

What software functions better in 64-bit mode ? StuRat (talk) 19:42, 10 April 2013 (UTC)

Theoretically anything available as 64-bit builds; realistically, ATM, in measurements you might actually care about: more server-oriented software. ¦ Reisio (talk) 20:03, 10 April 2013 (UTC)

You will have to reinstall to go 64->32. 2Gb is the very bottom end of MicroSoft's stated requirements for Windows7/64 (ref), with 1Gb for WIndows7/32. If you can at all manage it, new memory is almost certainly cheaper than your time. -- Finlay McWalterჷTalk 21:19, 10 April 2013 (UTC)

Yes, going up to at least 4GB is a lot better way to go. Except for one laptop with only 2GB, I've had 4GB in every machine that would take it, going back years. I now have 16GB. The 32-bit Windows maxes out at 3-3.5GB, depending on your system. I think 4GB per CPU is a good figure. Bubba73 ^{You talkin' to me?} 23:09, 10 April 2013 (UTC)

I'm not really convinced. 64-bit mode apparently doubles the memory requirements, yet offers very little in return, except for the ability to use the extra memory which it requires. To me that's like saying "Get the Chevy Suburban ! Sure, it burns twice as much gasoline, but you need to get it for the gas tank, which is twice the size !" StuRat (talk) 00:37, 11 April 2013 (UTC)

If your computer can handle 4GB of RAM and it has open slots, you can add 2GB from Crucial.com for under $40. If you have to pull out the memory you have to go up to 4GB, you can do it for about $72. I recommend going up to 4GB, at least. Look at it this way: MS says the 32-bit version needs 1GB and the 64-bit version needs 2GB. If you only have 2GB, you need more for your apps. The more memory you have, the better performance. Also, consider with 2GB and the 32-bit version taking 1GB, that leaves only 1GB for your apps (and disc cache). With the 64-bit version and 4GB of RAM, you have 2GB for your apps. Bubba73 ^{You talkin' to me?} 00:59, 11 April 2013 (UTC)

But don't 64-bit apps also require twice as much memory ? StuRat (talk) 06:31, 11 April 2013 (UTC)

Is your computer actually running like it is under memory pressure? Just because you are near the limit doesn't mean that it is actively using all that memory, and it can probably effortlessly swap out big chunks of it when there is a demand for more use. It might just be making good use of all your memory, making sure that the programs your using are using as much physical memory as possible. Of course, if your drive is constantly going crazy managing your swap, then you need to do something about it, but I'm just pointing out that high memory usage isn't alway a symptom of not having enough RAM. I had 4GB system at home that always ran near the limit, but it suffered no obvious performance hit when I borrowed 2GB of the RAM for another system.

Also, 64-bit apps don't take twice as much memory, the instructions and data are all the same size except for pointers, which will be 64-bit. 38.111.64.107 (talk) 12:00, 11 April 2013 (UTC)

Person of Interest (TV series)

In Person of Interest (TV series), there is a Machine, which monitors global communications, CCTV, etc, to determine terrorist threats, as well as premedidated murders. My question is, how feasible is this in real life. How much space would it take? -mattbuck (Talk) 20:56, 10 April 2013 (UTC)

It already exists. The National Security Agency runs it, in the US. It's not a single machine, but many. Of course, it can't actually predict the future, as it does in the show. I believe part of the set-up for that show is that there is info the NSA isn't concerned with, like potential murders, as that's not their job. This is why it gets farmed out to the characters on that show, supposedly, to do something about it. (In the show, they might call it the "CIA", instead of "NSA", as people are more familiar with the CIA. The NSA has done an excellent job of keeping a low profile.) StuRat (talk) 20:59, 10 April 2013 (UTC)

Are you talking about Echelon? Note that our article is full of "citation needed", and the more "reliable" refs are full of speculation. Nobody really knows what Echelon can or cannot do. But it probably cannot monitor CCTV mentioned by the OP (assuming wired, no broadcast), and it probably cannot read your email if you use PGP. SemanticMantis (talk) 21:12, 10 April 2013 (UTC)

Outside of acquiring the cameras and access to all communications, etc., the bottleneck isn’t space or hardware, but software, and just having a large set of data to infer from. ¦ Reisio (talk) 21:09, 10 April 2013 (UTC)

(edit conflict) Communications: ECHELON sending data to Trailblazer. In some countries automatic number plate recognition is centralised too. Some CCTV is centralised, much isn't. I doubt there's much real-time facial recognition yet, but it's a mostly solved problem, so the problem of integrating that with centralised CCTV and harvesting the result (being able to track a given person as they walk around a city) is a problem of organisation, scale, and legality (not really technology). TV, as usual, follows precedes reality (except for those curious blips that TV graphics still make, even though real computers stopped doing that in about 1980). We're not quite in the panopticon yet. The NSA article StuRat linked makes some statements about budgets and real estate, from which you can infer something of the scale of current efforts. -- Finlay McWalterჷTalk 21:14, 10 April 2013 (UTC)

Also relevant is Carnivore_(software). SemanticMantis (talk) 22:31, 10 April 2013 (UTC)

text files older than 10 minutes

From the command line on Windows I need to scan a directory for .txt files that are older than 10 minutes and execute a program if any are found. I have most of the common unix programs available to use. Thank you for your help. 92.233.64.26 (talk) 23:56, 10 April 2013 (UTC)

I think this will work, but I haven't tested it. It should find all files with .txt in the current directory that have not been modified in the past 10 minutes. For each of those files it will run FOO. find . -name "*.txt" -depth 1 -mtime 10 m -exec FOO {} \; RudolfRed (talk) 01:19, 11 April 2013 (UTC)

Why do we have cell phone contracts ?

Specifically in Canada. Why can't you get an iPhone 5 or galaxy s4 without a contract? Why can't someone just create a company without contracts but still offer smartphones? — Preceding unsigned comment added by 216.218.29.234 (talk) 00:04, 11 April 2013 (UTC)

Same on my side of the St Laurance; buyers only care about the discount on what they pay this year for this year's hot model, but sellers also care about the money they'll get next year. Incidentally I always buy last year's smartphone and never a contract. Every year I save on service charges more than I paid for full price hardware. Jim.henderson (talk) 00:13, 11 April 2013 (UTC)

You can get them without contracts. ¦ Reisio (talk) 00:25, 11 April 2013 (UTC)

Aren't those a little bit of a cheat, though? You can get a no-contract smartphone, but unless I'm mistaken, they usually work with only one provider, or am I wrong? So if you find a better deal with some other company, you can switch, but then your hardware is useless, unless you jailbreak it and take your chances with the evolving legal/political situation.

If I'm wrong about this please let me know — this is one of the main reasons I haven't bought a smartphone. --Trovatore (talk) 00:38, 11 April 2013 (UTC)

They should work with whatever, but you pay a much higher price (unless you get slightly older models, like Jim.henderson). Wireless providers sell them for less because they sell a greater volume and make more on the contracts anyways. ¦ Reisio (talk) 02:08, 11 April 2013 (UTC)

I think the problem is sticker shock. Let's say you have to pay US$1000 to buy a pre-paid smart phone with a year's worth of minutes on it. That would scare off many buyers. Even if they would end up spending that much with a contract, they don't have to think about it if they don't have to pay it all at once. StuRat (talk) 00:32, 11 April 2013 (UTC)

No, the problem is they make more money with contracts or hardware lock-ins. If they offered up full-priced phones without contracts and no hardware lock-ins, a significant number of people would snap up that option in a second. But the phone companies would make less money that way. --Mr.98 (talk) 00:48, 11 April 2013 (UTC)

There's no inherent reason why prepaid phones plans must be cheaper, overall. They do tend to be, but that's because they tend to offer lesser phones, no doubt to avoid the sticker shock I spoke of. StuRat (talk) 01:11, 11 April 2013 (UTC)

Mr. 98 isn't talking specifically about prepaid. The point is, what if you could buy a smartphone directly from Samsung or Apple or whomever, without a provider specified, and then make arrangements with Verizon or Tmobile or Sprint or whomever to provide you with service on that phone? The service could be prepaid, or it could be month-to-month, or whatever, but the point is that the providers would have to compete to serve you. Assuming they are genuinely competing rather than colluding, the price for service would presumably go down, but you would have to pay an honest cost upfront for the iron. --Trovatore (talk) 02:09, 11 April 2013 (UTC)

I would say everyone is making good points, but there's an extra thing, from having worked in a telco. You don't just walk in and say, I'll sign up for a casual plan, and let's take it from there. There are all sorts of different plans. That uses up a salesperson's time (which was me, once upon a time). Then you have to monitor what they are doing, and make sure they are bringing in money etc. Considering the staff time taken up, they presumably want more for it, with something definite for the half hour or more it can take (depending on whether the systems stuff up). Hence the heavy push towards contracts. If they bail at the last moment in a sale, it is a frightful nuisance for the company (and of course the salesperson). This isn't the whole point, but I would suggest it must be a factor - time consuming sales advice, for someone who could just jump ship at any moment. IBE (talk) 08:15, 11 April 2013 (UTC)

I think there's a lesson in there for dealing with salesmen. If you waste enough of their time, they might be willing to offer you a better deal to justify the time spent, if you threaten to walk away otherwise. However, in my case, I hate dealing with salesmen, and would much prefer an online app that can suggest the best plan, based on usage patterns and a brief questionnaire. If that saves everyone money, then all the better. StuRat (talk) 08:46, 11 April 2013 (UTC)

Accidental deletions

When editing, I often look at the keyboard as I type. When I look up, a good portion of the paragraph often has disappeared. I then use Control Z to undo the last few edits, and see that the chunk which was deleted was all highlighted at some point, then was deleted when I typed the next letter. I'd like to stop this from happening. The problem is, I don't know quite what causes it. Did I click the mouse accidentally as I moved it ? Did I double click when I meant to do a single click ? So, I'd like to disable a bunch of windows behaviors, in the hopes of stopping this. Which of the following can be disabled, and how ?

1) Can I stop Windows 7 from highlighting a word if I double click (or a paragraph if I triple click) ?

2) Can I stop Windows 7 from replacing the entire highlighted text when I type something new ? Instead it should add what I type after the highlighted text.

3) Apparently if you click the mouse while moving it across text, it grabs a random chunk of text and moves it. Can this be disabled in Windows 7 ? StuRat (talk) 01:08, 11 April 2013 (UTC)

Are you perhaps using a laptop? Does it perhaps have a touchpad? Looie496 (talk) 01:29, 11 April 2013 (UTC)

Most laptops have a key that, typically combined with a function (Fn) key, will disable/enable the touchpad. ¦ Reisio (talk) 02:11, 11 April 2013 (UTC)

No to both. Desktop with mouse. StuRat (talk) 06:28, 11 April 2013 (UTC)

cripto

here is an app i wrote. i need to know what cryptographic attacks can be used against files encrypted with it (just point me to the article). also, when brute forcing an encrypted file, how do you do it if you don't know the sceame used to encrypt it? and how do you know when you have the key? thank you, 70.114.248.114 (talk) 02:29, 11 April 2013 (UTC)

#512 bit cypher, takes var-length password, hashes in sha512, xors each 512bit chunk of file with hash.
#to use: input name and path of file to encript or decript, input password, input name of encripted file. to decript: input name of encripted file, password, and name of new decripted file.

#"open('path','ab')" creates file if it doesn't exist.

def block(data,key):
    #make empty array for altered data.
    alt_data=[]

    #alter each byte of "data", append it to "alt_data", and return.
    i=0
    for byte in data:
        alt_data.append(ord(byte)^key[i])#ord converts chr to int.
        if i==len(key)-1:
            i=0
        else:
            i=i+1
    return alt_data


import hashlib
#read file into string (data).
file_=open(raw_input("input-file path: "),"rb")
data=file_.read()
file_.close()

#make empty array for key and input pass-word.
key=[]
password=str(raw_input("password: "))

#make key by hashing password. keyhex is hex string of key.
sha=hashlib.new("sha512")
sha.update(password)
keyhex=sha.hexdigest()

#convert keyhex to int and append to array "key".
i=0
while i<128:
    key.append(int(keyhex[i]+keyhex[i+1],16))#int convert needs base (16).
    i=i+2

#encript or decript data.
newdata=block(data,key)

#open output-file and write en/decripted data to it.
out=open(raw_input("output-file path: "),"ab")
for b in newdata:
    out.write(buffer(str(chr(b))))
out.close()
print "done"

(i forgot to put the code.)

I think that if you run it on a big enough text file, it can be broken without too much trouble. About 19-20 years ago I wrote a program to break the 40-bit equivalent on English text files, on a 60-MHz Pentium I. Bubba73 ^{You talkin' to me?} 05:31, 11 April 2013 (UTC)

Yep, just picture arranging the output in a table with 64 bytes (512 bits) per column. In a column, each character is xor'ed with the same value, so you just loop through the 256 possible values until you get one that gives reasonable output. Do this for each column and you've worked out the plaintext and the 512 bit hash. There's no need to figure out the original password. For a text file, this would be trivial to automate - the odds of there being more than one key character for a column that gives a reasonable mix of characters must be pretty low. For decrypting other files, knowing details about the file format helps. If you know the plaintext has a given header, or tends to have large chunks of zero bytes, or otehr details like that it can make it pretty easy to work out huge parts of the key hash. 38.111.64.107 (talk) 12:55, 11 April 2013 (UTC)

This is a variation on the Vigenère cipher. -- BenRG 07:39, 11 April 2013 (UTC)

whats the html tag to make a page unspidered?

thanks, 70.114.248.114 (talk) 02:30, 11 April 2013 (UTC)

See robots.txt. ¦ Reisio (talk) 02:42, 11 April 2013 (UTC)

thanks. but is there an html tag to tell spiders not to index the html page the tag's on? and that gives me an idea. could one write a script to check the reference desk at regular intervals to see when someone posts a new section, or when someone answers yours? and would the terms of use be violated by this? thanks, 70.114.248.114 (talk) 03:06, 11 April 2013 (UTC)

“is there an html tag…”

Not that I’m aware of; and even if there were, like robots.txt there would be no way to enforce compliance 100% of the time.

“could one write a script…”

Yes.

“would the terms of use be violated…”

No.

¦ Reisio (talk) 04:46, 11 April 2013 (UTC)

• There is such a tag, sort of. See noindex. Looie496 (talk) 05:48, 11 April 2013 (UTC)

what does "mining for bitcoins" mean?

thank you, 70.114.248.114 (talk) 05:55, 11 April 2013 (UTC)

Bitcoin / Bitcoin#Bitcoin_mining ¦ Reisio (talk) 06:07, 11 April 2013 (UTC)

April 11

Weird phenomenon on YouTube

A lot of times when I watch videos on YouTube, the visual part of the video seemingly "freezes" for 10 seconds, but the audio part keeps running as usual, and by the time the visual part continues, 10 seconds of visual content is skipped. Has anyone else experienced this before? If so, can someone explain why this happens? 24.47.141.254 (talk) 06:20, 11 April 2013 (UTC)

Best closed-back headphones

Can anyone recommend me closed-back headphones that are under 40 bucks, as well as a cheap headphone amplifier? Thanks. 70.55.108.19 (talk) 10:36, 11 April 2013 (UTC)