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July 14

sprint and text/sms costs?

Hey, im using http://www.textem.net/ to communicate with a friend. They have sprint. according to one of the responses here http://sms411.net/2006/07/sprint-sms/ sprint has really bad service switching from email to phone, which i THINK textem uses... maybe they somehow send a message directly? not sure.

Anyway, i'm having big issues with my messages not going through, and also with not getting messages from my friend. I dont know if its the site or sprint or both.

If i text them using email (######@messaging.sprintpcs.com) will i get better service? will it cost them where textem doesnt?

I just want to find a way to text RELIABLY for free, hopefully not costing my friend either. Is this possible? Opinions and any pertinent info please!

Thank you very much! 172.163.26.218 (talk) 02:56, 14 July 2011 (UTC)

Macbook hardware diagnostics (memtest, disk drive)

I am trying to help a friend who has a Macbook Pro with an Intel processor. I'm trying to install Mac OS X Snow Leopard, but it hangs in the middle of the install.

If this were a PC I would load up Ultimate Boot CD for Windows and run memtest86 and a hard drive test, but I obviously can't do that on a Mac.

During the install, I have tried to erase and reformat the hard drive, that does not help. I have run the verify and repair tools on the hard drive, that doesn't help either (they both 'pass').

Q: How can I diagnose problems with either the memory or disk drive on a Mac, if I can't boot into the operating system?

Thanks, TheGrimme (talk) 03:47, 14 July 2011 (UTC)

Memtest86 will run on a Mac. Download an ISO of it and give it a whirl. --Mr.98 (talk) 03:54, 14 July 2011 (UTC)

Thanks Mr.98. I burnt the iso and tried booting with it. Doing nothing, the disk spun but the computer just showed a picture of a folder with a question mark. I found a youtube video that said to hold alt, and instead of that image it remained at the gray screen with an arrow for a cursor. Either way, it didn't seem to want to boot with memtest. Any ideas for memtest? Any ideas for testing the hard drive? Thanks again, TheGrimme (talk) 05:11, 14 July 2011 (UTC)

Do you have an OS X DVD? I would try to boot from that. There is a hardware diagnostic program on the DVD as well. --Mr.98 (talk) 14:44, 14 July 2011 (UTC)

I do have the OS X Snow Leopard retail DVD, but not the hardware testing disk that (after reading many forums) apparently comes with an Apple computer when you purchase it. The only tool the DVD gives me is the disk utility, which after 4 seconds says the disk is fine. This is not an accurate disk check. — Preceding unsigned comment added by TheGrimme (talk • contribs) 18:18, 14 July 2011 (UTC)

You should be able to get the original OS X disk that came with the machine from Apple, if it has been lost. Even if your support contract has expired, the Apple help line might give you some ideas. You did not say what OS is currently on the machine. If you can get the OS X disk that came with the machine, you can boot from that, regardless of the state of your hard disk. EdJohnston (talk) 18:59, 14 July 2011 (UTC)

How do I forcibly move some stubborn Android apps onto the SD card?

On my Sony Ericsson Xperia Play, I only have 380 MB of internal memory. I remember when 380 MB was a LOT (alas, that was in 3rd grade.) However, I have gigs on my SD card.

The only problem is, some apps won't let me move them to SD cards and I'm running out of room. Therefore,

1. How do I forcibly get those said apps onto the SD card anyway?
2. How do I swap out the internal 380MB card for a bigger one, and transfer all the internal data to the bigger one?
3. Being low on internal space, will new apps download directly to the SD if they're eligible for it? (Or do I have to manually change something to let that happen?)
4. On the Android market, how do I tell whether the apps are eligible for the SD card?
5. Is there an app that removes the stubbornness of those apps that normally won't let me move them to the SD card, by way of somehow changing that particular permission?

Having hoarded hundreds of fine apps, now would be a great time for epic assistance. --70.179.165.67 (talk) 03:54, 14 July 2011 (UTC)

There are some apps that will force other apps to an SD card. When an app is made, the programmer decides if it will be allowed to move to the SD card. For development, you can move things around. So, you get a developers app and put that on your phone and you can do things that a normal user cannot do. This is not completely rooting the phone - it is just a developer tool. Unfortunately, not all apps will work properly if run from the SD card - especially if the SD card didn't initialize properly when you turned on the phone (a common problem). Most of these apps that allow this environment have names like SDMove or SDForce. Also, they tend to be ones you have to download, compile, and install yourself.

I haven't seen an Android phone yet that allows you to alter the internal storage in any way. You can only change out the SD Card. Even the Droid Global (which allows a lot of hand-on) doesn't let you get to the internal storage without mutilating the phone.

As with the "move to SD card" apps above, there are developer's tools which force everything to the SD card. They tend to be called things like App2SD. Again, they usually require you to download, compile, and install them.

I do not see anything in the App store which allows you to see if an app can be moved to the SD card. I just uninstall the stupid ones that can't do SD card (like the new Google+ Android App - you'd think that Google would be able to make a good app).

The last question is a repeat of the first question. -- kainaw™ 12:53, 14 July 2011 (UTC)

USB gamepad on Linux

I'm running Ubuntu 64 Natty, and have installed a cheap gamepad with two axes on an 8-way d-pad (not analogue) and 10 buttons. I'm having a few problems.

• First, the number of axis registering in Linux is 6, not two, and the two axis that exist are not the first two that Linux acknowledges.
• Second, even after remapping the two axes that actually exist to 0,1, although the gamepad appears to work in jstest, neither of the games with which I've tried it acknowledge my use of the d-pad. Presses on any of the buttons are recognized, but not the axes.

Any ideas?--Leon (talk) 14:13, 14 July 2011 (UTC)

mod_rewrite and .htaccess help

I'm trying to set up an .htaccess file with mod_rewrite that will take all traffic and shoot it to one page.

So let's say I have http://mysite.com/index.php, which is my main "controlling" page. If you go to http://mysite.com/blah/hello.html (or any other subpage query of mysite.com), I want it actually to load up index.php, but not change the URL path as far as the browser is concerned. index.php will then analyze the URL string and serve up content appropriately.

My gut says mod_rewrite is the way to do this, but really, I've got no clue how to use it correctly. Seems like a lot of regex strings and I'm not too keen on those.

Anyone have experience with this who can lend a hand? --Mr.98 (talk) 15:06, 14 July 2011 (UTC)

Nevermind, I figured it out. The Wordpress htaccess settings here did the trick. --Mr.98 (talk) 16:18, 14 July 2011 (UTC)

Fake PayPal email

I am in the UK. I've got an email suppopsedly comming from PayPal. However the "from" address has nothing to do with PayPal, and the link I am asked to click on redirects to a web address that ends in .tw.

What should I do about it or with it, if anything? I've already marked it as junk mail. 92.24.177.241 (talk) 18:41, 14 July 2011 (UTC)

Just delete it and ignore anything similar, its common for spammers and scammers to send fake emails claiming to be from banks and whatnot in an attempt to get you to give them your details.--Jac16888 ^Talk 18:43, 14 July 2011 (UTC)

But, how do they fake the email address? I sometimes receive the email with exactly the address of a real bank (like clientservice@realbank.com) not a thing near it (like clientservice@realbank.tw). Quest09 (talk) 21:15, 14 July 2011 (UTC)

An email is just a text file. At the top are some email headers, which are just name:value pairs. Any email library lets you set the values to all of these, and make up any old ones you like. As the mail is moved around between mail servers they often add other stuff (the route it took, whether that server thinks the email is spam, etc.) but stuff like From: and Date: are rarely touched. So it's trivial to set a From: to read as anything you want; it's also common to manipulate the date: to either be in the future or the distant past (so it's at one end or other of the recipient's email list, if it's sorted by date). -- Finlay McWalter ☻ Talk 21:23, 14 July 2011 (UTC)

(edit conflict) They fake it by tampering the "From:" header that indicates the sender, which is read at face value by your email client. That can be thwarted by verifying the header with a public key from your bank, but it is a pain to do if you're a normal user (actually, it is a pain to do not matter how experienced you are). With these things, the best thing is to be skeptical, and exercise caution with emails regarding your bank. Don't click on links included on the email, and contact your bank if there is something particularly suspicious - frankie (talk) 21:25, 14 July 2011 (UTC)

(The technique is known as E-mail spoofing.)--Kateshortforbob _talk 22:12, 14 July 2011 (UTC)

I have an e-mail here & I know who sent it both from the "from" address & by the content. But suppose I get an e-mail apparently from the same person at the same e-mail address. If something in the content makes me suspicious as to whether they sent it, would comparing the two headers establish whether the new email is fraudulent? Thanks, Wanderer57 (talk) 23:25, 14 July 2011 (UTC)

It depends on how well the spoof is made. If they only changed the "From: " header, then you could compare the other headers for clues on whether it is legit, but those headers may be altered just as easily. In the scenario you present, you have the option to contact your friend to confirm if the email is from them, but then it could happen that that communication channel could be compromised as well, so a new approach would be required. Regarding IT security, there is always a degree of speculation and uncertainty, regardless of any measures taken - frankie (talk) 13:32, 15 July 2011 (UTC)

I once got a fake PayPal e-mail which had even copied PayPal's warning "If in doubt, write the address to your browser by hand instead of clicking on links" verbatim. A self-defeating scam e-mail! =) 194.100.223.164 (talk) 09:43, 15 July 2011 (UTC)

Quite in contrary. They look more reliable doing that, since people dont expect scammers to use such sentences. They are reducing the "doubts". — Preceding unsigned comment added by 88.8.79.148 (talk) 11:16, 15 July 2011 (UTC)

But the scammer is instructing the user to avoid doing the thing that the scammer wants him/her to do, because if the user types in the URL by hand, he/she will get to the real PayPal site. Unless of course the fake e-mail includes a forged link that has not only the actual URL, but the displayed text forged too, and the user happily types in the forged URL by hand. 194.100.223.164 (talk) 13:27, 15 July 2011 (UTC)

I used to get fake messages from 'Ebay' allegedly including a message from the customer that I failed to pay for some stuff I had never seen in my life, but I didn't get fooled. And I also got fake e-mails from Paypal, but I never had an account with them, so no bother there. For the bank bit, I specifically asked my customer care person the last time we talked that I don't want anything sent to me, be it e-mail or snail-mail, save for new debit cards if I request one. So when in doubt - doubt even more! --Ouro (blah blah) 11:31, 15 July 2011 (UTC)

Phone hacking

How do I keep my cell phone from being hacked? — Preceding unsigned comment added by 207.157.87.136 (talk) 20:25, 14 July 2011 (UTC)

See these articles: [1] and [2] -- Finlay McWalter ☻ Talk 20:39, 14 July 2011 (UTC)

Been in the UK, you don't have to be a celeb to get your phone hacked, apparently. I understand your worries. Quest09 (talk) 21:16, 14 July 2011 (UTC)

The news keeps talking about cell phone "hacking", but it isn't much in the way of hacking. Most phone message boxes require a 4-digit code to access the messages. You don't have an option to use more than 4 digits. If you don't set it, you get a default one, like 0000 or the last four digits of your phone number. So, a group of journalists call in and try the obvious choices: 0000, 1234, etc... They guess the 4-digit code and have full access to the phone messages. Never do they touch the actual cell phone. They don't have to see it, call it, or do anything to it. They are just calling the phone company's mailbox number, typing in the phone number for the mailbox they want to check, and guessing at the access number. Because there are only 10000 choices, it is rather easy to guess it by using brute force: get 10 people and have each one try 1000 possibilities. You'll get it in a couple days. -- kainaw™ 16:22, 15 July 2011 (UTC)

Computer memory

If a computer is restored to an earlier period in time, will the hard drive memory stay the same as it was in either that certain period time or the current that I was in? I'm going to be restoring a computer, and I just want to ahead of time since I've never restored a computer. SwisterTwister talk 22:22, 14 July 2011 (UTC)

I'm not entirely familiar with it, but according to System Restore and this MS support post it only affects system files and registry entries, while your personal files are unaffected (and, conversely, your personal files cannot be recovered by performing a restore in the event that you deleted them). I hope that helps - frankie (talk) 22:28, 14 July 2011 (UTC)

Still, it is always a good idea to make a backup of your files, just in case - frankie (talk) 22:31, 14 July 2011 (UTC)

Sorry, you need to be a little more specific about what exact operating system and additional software (if any) you are talking about. I suspect that Frankie is correct and that you are talking about the Windows Vista or Windows 7 System Restore, in which case Frankie is correct: all that gets affected is the system files and registry. The purpose of System Restore is that if you install some bad, nasty software that breaks your system somehow, you can use System Restore to "rewind" to before the install occurred, when your system worked. The files in places like the "Documents" folder won't be affected.

On the other hand, you may be referring to backup software like Norton Ghost, which can back up your hard disk to an image file that's a complete bit-for-bit image of the hard disk, and when you tell Ghost to "restore" the hard disk to an earlier date, it'll replace every single bit of the hard disk with the backup image file; so indeed your hard disk will look the same as it did the day it was backed up. Comet Tuttle (talk) 04:21, 15 July 2011 (UTC)

July 15

Just installed IE9. I have a serious problem with it that seems to make it useless for me.

I note that a "separate search box" has been deleted from IE9. I definitely want to use Bing, Youtube, Hulu and other search providers. When I had IE8 I found that Google had outdated useless results (a year old) and Bing had more recent results for an important recent search. I prefer to use as few toolbars as possible to preserve space for results. Am I limited to Google via its toolbar? Can't find from Microsoft on how to roll back to IE8.1archie99 (talk) 03:30, 15 July 2011 (UTC)

If you click the down arrow beside the little magnifying glass in the address bar, it'll pop down a list of recently visited sites and favorite sites. At the very bottom of that is a line with icons for all the different search providers you have available (think it's just Bing when IE9 is initially set up). In the bottom right corner is an "add" button to add new search providers. Then just click on which one you want to use. 75.155.138.12 (talk) 08:47, 15 July 2011 (UTC)

You can also set your home page to be your favorite search engine. That's what I do. That way, any time you open a new tab, you get that search engine. As for Google getting old results, that makes me wonder in Microsoft is intentionally using cached values for Google, to make it less useful and encourage people to move to their product (Bing). StuRat (talk) 18:22, 15 July 2011 (UTC)

Defaul video player; detecting which is playing and changing it

How do I tell what program my imac is accessing to play mpgs and other videos when I click on them at a website? It's playing this tiny clip in the center of the screen and I know that at some point I was able to change my default player to something else but I don't know how and I recently reconfigured. So a few questions. How do I tell which program is running to play the clip (this is embedded on a website, not a clip I've downloaded that if I played, the menu at the top of the screen would show me the program) and how to I change the default program that playes these. I think what's playing them right now it quicktime, because I remember from a long time ago that when anything plays through quicktime it would open in that tiny screen, but I'm not sure. Thanks.--108.46.103.142 (talk) 04:16, 15 July 2011 (UTC)

When you click on them in a website, your browser is deciding how to handle them. You can look up how your browser handles a given file type in its Options or Preferences or whatever it calls the thing. Looie496 (talk) 05:35, 15 July 2011 (UTC)

Registry cleaning

In short, is registry cleaning worth bothering with, and if so, which cleaner?

For old times' sake, I occasionally use an old computer with Win2k. For a long time it ran roughly as fast as my assistants' machine, with XP, which has more memory, and a far faster CPU. But I had to swap the latter with another, nominally identical (old) machine. This is a slug; my Win2k machine runs rings around it. And it's not just me: a friend in the same predicament says that her new old XP machine is a slug compared with its predecessor.

First I suspected the "antivirus" software. I really want to delete this, but I suppose I have a civic duty to run "antivirus" software as long as I'm running Windows; and I don't know of a significantly less annoying "antivirus" alternative.

Today I heard an acquaintance complaining about grotesque sluggishness in other (newer) Windows computers hereabouts. He'd run a registry cleaner on one, zapped over 300 pointless registry entries (from old versions of software, etc), and the machine thereupon booted and ran far faster, he said. Sounds promising!

However, the general thrust of the article "Registry cleaner" seems to be that "cleaning" your registry is about as good for your computer as chiropractic or homeopathy or moxibustion is for your body. Moreover, some googling for putatively independent information brings very dubious looking web pages, showing as " contest winners" laughably huge cardboard boxes.

Then again, the WP article "Registry cleaner" is feebly sourced....

So what's the straight dope on registry cleaning? If it has some value, is there a no-bull (no large cardboard box) GNU or similar program for the job?

(Please don't advise me to switch to Linux. It's excellent advice, which I've already taken. The Windows computer is for anyone who happens to be working with/for me, not for me. And these people seem oddly worried by anything other than Windows.) -- Hoary (talk) 06:47, 15 July 2011 (UTC)

Contrary to the about comment by Hoary, chiropractic is a very effective treatment for some conditions. I know this is not a good place for a discussion of chiropractic but I cannot let that comment pass unchallenged. Wanderer57 (talk) 18:44, 15 July 2011 (UTC)

Don't know nothing about cardboard boxes to clean the registry with, but as one who had moved away from Windows quite a while ago, I can tell you this much: yes, cleaning the registry will speed things up to some extent, depending on the individual machine, actually. Can't recommend any particular software for it, because back when I still had any flavour of Windows, I usually a) just installed stuff I really needed, and b) just reinstalled the OS once every few months. There's a c), I did a little bit of cleaning by hand (but just a little bit - just the keys related to apps running at start-up), but that's kind of marginal (but still able to speed thing up somewhat if you do it right). Cheers, Ouro (blah blah) 11:24, 15 July 2011 (UTC)

Most registry cleaner programs are garbage that perform no useful function. To make it worse, many registry cleaner programs are front-ends for trojan horse programs.

Ultimately, you should ask "why will cleaning the registry speed up my computer?" Your computer's speed is determined by its hardware. If you notice that your computer is not meeting its peak performance specifically because unwanted programs are running, you should stop (or uninstall) those specific programs.

When you have many programs running, you are sharing your CPU and RAM with many programs. If you have unwanted programs that are running, turn them off; or disable them from starting when you boot your computer. You do not need any special tools: just know what programs have been installed, and disable (or uninstall) the ones you do not need. You can learn more about how programs auto-start in Microsoft Windows and how to configure which programs start on boot. Any legitimate "registry cleaner" program that provides a "speedup" is doing exactly these steps; but, by having software perform these steps for you, you are risking any of that program's side-effects or malware.

One of the biggest misconceptions is that "lots of clutter installed on the hard disk" slows your computer down; this is generally untrue. Modern computers are for the most part performance-agnostic with respect to the amount of data on the hard-disk. (Data on disk may cause minor variations in disk seek or file system performance, but this is not really what you experience when your computer is "running slowly.") The most critical factor that affects performance is the number of programs currently using CPU and RAM. Your Windows Registry, a utility that Windows uses to store and share data between programs and services, has essentially nothing to do with this performance. Nimur (talk) 15:32, 15 July 2011 (UTC)

There is something that many registry cleaners also do, which can improve performance dramatically. That is to edit the list of startup programs. These programs are started each time you log on. Unfortunately, when you install many programs, they insert the command to start up a background process every time you boot. One common function of these backgound programs is to check for updates. This sounds innocent, but if you have dozens of programs all checking for updates each time you log in, that will really slow things down. To me, the more appropriate behaviour is to only check for updates when you request a check (or perhaps when you start that specific program), so I disable all those. An exception is for updates to Windows, itself. StuRat (talk) 18:11, 15 July 2011 (UTC)

Ccleaner is well thought of, and can also be used to control what starts up. I also sometimes use RegCleaner 4.3 by Jouni Vuorio, using the "do them all" option: never had any problems. Both free. 2.97.208.91 (talk) 21:18, 15 July 2011 (UTC)

Thank you, all. I find Nimur and StuRat's comments particularly convincing. And it seems that Ccleaner and RegCleaner (semi-) automate, or streamline, some tasks that seem worthwhile even to non-believers in registry "cleaning", so I may well experiment with one or the other when I return to my Windows computer next week. Again, thank you all for your constructive and useful comments. -- Hoary (talk) 00:49, 16 July 2011 (UTC)

Samsung Infuse 4G

Can anyone summarize the known pros and cons with the Samsung Infuse 4G and compare it to other phones of the same class on the market? Viriditas (talk) 09:27, 15 July 2011 (UTC)

Yes. Anyone can do this. Just Google phone compare.--Shantavira|^{feed me} 09:44, 15 July 2011 (UTC)

Where I am, it will be July 15, 2011 in a few minutes. Most of the information you refer to is out of date represents brief opinions from early adopters and does not have information from users who have used the phone for some time and have an educated opinion of it. Viriditas (talk) 10:00, 15 July 2011 (UTC)

I'm sorry, I don't know. However, I do note that Wikipedia (not a reliable source) says: The advertisement for the Samsung Infuse 4G is notable for depicting a woman screaming at the image of a tarantula spider on the phone, and a man beating the phone with his shoe. Itself unsourced, but if true, surely worth a couple of brownie points. The name isn't as good as "Boulder" (surely one of the all-time great names for a mobile phone) but far less horrible than "Commando" (which I'm contemplating, despite its name). Either way, I hope that you make a good choice. -- Hoary (talk) 10:23, 15 July 2011 (UTC)

Someone Help Me Please My PRograms Arent Working!

For some reason when I turned on my laptop computer it tried to run all of its programs with Notepad instead of how they run normally! Can someone help me how to reverse fix this problem My computer is a Windows 7 laptop computer it can turn on to desktop fine but then it starts to run or attempt to run its programs such as gadget bar with Notepad. I need this fix quickly Thanks in advanced 1.52.90.241 (talk) 14:08, 15 July 2011 (UTC)

It would seem as if the executables and shortcuts have become associated with Notepad, maybe because of some virus that replaced the .exe and .lnk extensions with .txt. I found these three posts from Yahoo answers [3] [4] [5] that might be of help. Still, that is only a theory; you should look for someone that can take a look at the computer to see what is going on specifically - frankie (talk) 14:44, 15 July 2011 (UTC)

No it doesnot seem to be a virus and all file extensions are kept It just seems that everyting is running with Notepad despite that. Maybe i just need to know how to change default file opening program from Notepad to standard how do I do that? 183.80.223.43 (talk) 15:00, 15 July 2011 (UTC)

For individual files you can right click on it, and then under "Open with" select "Choose program" (note there is a checkmark on the resulting window to make your selection permanent). For a list of all file types you need to go to "Folder Options" (open any folder and it should be somewhere on the menu on the top left; I'm not on 7 right now and I don't remember exactly), and once you're there go to the "File Types" tab, which lets you specify which action to take for each file type - frankie (talk) 15:29, 15 July 2011 (UTC)

There is no Open With option. I just want to restore program opening with their intended originals instead of with Notepads 1.52.42.117 (talk) 16:09, 15 July 2011 (UTC)

That's odd. Check this link [6]. I wouldn't recommend installing the program mentioned at the bottom, though (for no particular reason, it just seems that the last thing you need right now is to install another program that might or might not work, and the functionality is included in Windows) - frankie (talk) 16:42, 15 July 2011 (UTC)

It seems that the OP's problem isn't with file associations so much as .exe files not working correctly. A quick search for "exe files open in notepad" provided many results. This page may help, and MVPS is a reputable organization. --LarryMac | Talk 17:55, 15 July 2011 (UTC)

Open the Control Panel, go to "Default Programs->Associate a file type or protocol with a specific program", and look at the list of associations you get -- this will tell you what program is set to open each file type. You ought not to see .exe in the list. Looie496 (talk) 18:09, 15 July 2011 (UTC)

Remember that I am using Windows 7 not Vista they are both very different so I cannot find this "Default Programs" you speak of... 1.52.55.125 (talk) 03:43, 16 July 2011 (UTC)

Sorry, it's inside the "Programs" part of the Control Panel. (This is Windows 7 I am referring to.) Looie496 (talk) 05:20, 16 July 2011 (UTC)

Two things that might account for what you are seeing:

• The 'assoc' command has either removed or altered the file association for exe files. If you can open a command prompt, the command "assoc .exe=exefile" should restore exe files to their normal working. "help assoc" will tell you something about this command.
• Something (a virus/malware?) has renamed your programs to end with .txt; so for example "WinMail.exe" becomes "WinMail.exe.txt". Coupled with the option to "Hide extensions for known filetypes" in the Folder Options control panel, the program still looks like "WinMail.exe" in Windows Explorer except the icon might have changed to a sheet of lined paper. Astronaut (talk) 14:28, 16 July 2011 (UTC)

Bridged Client Mode

Hello. I've set up "Bridged Client Mode" on an OpenWRT-firmware linksys WRT54GL router, to bridge it to my other Linksys (original firmware) router connected to the Internet. When I plug a wireless-disabled computer into one of the ethernet ports in the bridged client router, I can access my LAN and the Internet without any problems. However, it seems like my wireless devices don't connect to the bridged client router wirelessly. What do I need to do so that my wireless devices know to connect to the bridged client when the access point is weaker or out of reach? Thank you for your help.--el Aprel (^facta-_facienda) 20:21, 15 July 2011 (UTC)

Power on/off on a single USB 2.0 port?

Is there an application to turn power on and off repeatedly on a single USB 2.0 port while the computer is running? Is it even possible physically, or are all the power and ground leads of the USB ports hardwired to the computer power supply? The computer in question is a standard HP laptop under Windows. Thanks. --Dr Dima (talk) 21:03, 15 July 2011 (UTC)

As to physical possibility: the USB3.0 spec (and I believe 2.0) does allow "host initiated suspend" (section c.1.4.3); that's not quite the same as "off" (as the device can be told to wake from that state) but the intention is that the device draws as little power as possible in this mode. As for being completely off, that would strictly be a property of the host controller rather than of USB itself. Intel's UHCI document dodges the issue, but the EHCI document talks about an optional feature that EHCI-compliant host controllers can have - PPC (power port control); controllers which implement PPC have a per-port power control, and can completely depower that port (section 2.3.9 PORTSC and 2.2.4 HCCPARAMS). So the question remains as to whether, and how, Windows provides access to these functions. There is driver level support, but I can't see anywhere that this functionality is exposed to user mode programs - all the uses I can find of it is by the system's own power manager (so it can put USB devices to sleep when it's switching to a lower power mode, etc.). -- Finlay McWalter ☻ Talk 22:33, 15 July 2011 (UTC)

If you're asking with the idea of controlling something (like flashing a light or turning on a motor) using a USB port, there are better ways of doing this. Typically one would use a USB - connected microcontroller board like an Arduino to do the electrical part, and drive it with a simple program on the PC, which sends it commands over the USB port. -- Finlay McWalter ☻ Talk 22:33, 15 July 2011 (UTC)

Yup, that's exactly the idea: I need to drive a LED (total cost with a matching resistor: 32 cents) without having to pay $30 for a microcontroller board, LOL. Can this be done? --Dr Dima (talk) 01:17, 16 July 2011 (UTC)

It seems unlikely you need anything complex enough to cost $30. A cheap 8 pin, 8 bit MCU like a PIC or something I'm guessing should be able to handle it. You'll need a way to program it, you could use something like a serial programmable PICAXE. Of course if you still have a serial port you could potentially just use that presuming you're not trying a high power LED (and perhaps a white or blue LED since I'm not sure if the voltage of the serial port is high enough). It's possible to make very cheap LIRC devices which function off the serial port and work in a somewhat similar way (although flashing the LED at a much higher rate). Nil Einne (talk) 13:39, 16 July 2011 (UTC)

I guess you could adapt this heinous hack to your purposes. But stuff like this makes sense only if you want to hack stuff from next to nothing on principle, or if your time is very cheap indeed. -- Finlay McWalter ☻ Talk 14:23, 16 July 2011 (UTC)

A while ago on this desk, someone (unfortunately I don't remember who) suggested this hack to a similar question: take a keyboard and use the NumLock, CapsLock, or ScrollLock as your led, and toggle them programmatically on your computer. This can be done in just one line of code in, e.g., Java:

java.awt.Toolkit.getDefaultToolkit().setLockingKeyState(java.awt.event.KeyEvent.VK_CAPS_LOCK, true);
//or false to turn off. Use VK_CAPS_LOCK, VK_NUM_LOCK, and/or VK_SCROLL_LOCK

This would be much easier than dealing with the low levels of the USB interface, although it might not be a completely satisfactory solution for you.--el Aprel (^facta-_facienda) 03:18, 17 July 2011 (UTC)

Age of my computer?

I'm using a second hand WinXP computer that is a few years old, but works very well for my needs as I never do anything computationally intense. Is there any way to tell via software, and without taking it to bits, how old it is? 2.97.208.91 (talk) 21:24, 15 July 2011 (UTC)

Run Speccy, and under the motherboard section it should state the date AvrillirvA (talk) 21:47, 15 July 2011 (UTC)

Thanks, the WinXP instalation date is given as 2005, the BIOS date is 2004. 92.24.138.48 (talk) 15:33, 16 July 2011 (UTC)

Steam problems

recently, my computer underwent a regularly-scheduled update, but now Steam won't start. A Steam connection error box appears stating that "you either are not connected to the internet, or your internet connection is not configured correctly for Steam." I know I have my internet connected and Steam has worked perfectly for over a year up to now.

Steam will start in offline mode, but for some reason I cannot play any of my games in offline mode, not even ones like Half Life which aren't Internet-based.

The only other notable fact, when starting up an Updating bar appears, but does not even start filling up. After a few minutes, the 'correction error' screen appears.

I am currently at a college, so I do not have access to the router. Is there a solution to the problem that does not require a router? 163.1.151.174 (talk) 22:31, 15 July 2011 (UTC)

Perhaps the college's network admins have recently taken steps to block the ports necessary for Steam to work properly. These are described here, with a note at the bottom about colleges blocking it. It's possible that they've done so inadvertently: perhaps they had allowed the traffic, but have updated their router firmware and have lost their customisations, returning it to a more strict default. Either way, the college network admin people are the ones to talk to. -- Finlay McWalter ☻ Talk 22:43, 15 July 2011 (UTC)

Another option is that you have some local personal firewall (like Zonealarm or McAfee) which is blocking the same ports; you need to add exceptions to that to allow the outgoing steam connections. -- Finlay McWalter ☻ Talk 22:43, 15 July 2011 (UTC)

Just adding about the offline mode, it doesn't quite work the way you would think it should: It's part of their anti-piracy techniques and it's actually preparing a game so that it can be used temporarily offline in the future and you have to actually have an Internet connection to do this. As far as I know there's no way to "force" a game into offline mode as it needs confirmation from the Steam servers first (and it's only temporary because the next time you go "online" it will wipe the offline configuration).  ZX81  ^talk 00:14, 16 July 2011 (UTC)

July 16

JAVA,(J2EE),net or php

Which is better among three of these — Preceding unsigned comment added by Ruchibahl18 (talk • contribs) 06:18, 16 July 2011 (UTC)

Better in what way? --Mr.98 (talk) 13:27, 16 July 2011 (UTC)

The conventional wisdom regarding programming languages/tools is that it always depends on what you are trying to do. Java is well acknowledged for its platform flexibility, J2EE is good for highly designed (web) software projects, .NET has slightly better performance than java and allows for multiple different languages to be compiled to the same bytecode, php is well known for being good for "quick and dirty" web applications. If you want to know which of those are best to study as a carreer move, Java and .NET represent the majority of paying programming positions, though quality of the job and pay varies. Your question is impossible to answer simply. i kan reed (talk) 16:18, 19 July 2011 (UTC)

Drag and Drop Won't Work in Book Creator Editing Area

Greetings.

I've used the book creator successfully to make a couple of books, but it seems (and I may be completely off, here) that since installing Internet Explorer 9, I can no longer drag and drop chapters or articles within the Book Creator editing area. While hovering the cursor over a topic or chapter name, I get the 4-pointed arrow icon instead of the hand icon.

I've tried switching use from IE9 64-bit to IE9 32-bit. I've lowered security regarding cookies within IE9. I'm running Windows 7 Home Premium, 64-bit.

I would appreciate any assistance in this matter, as the Book Creator is virtually useless to me while the drag and drop function is dysfunctional.

Thanks. — Preceding unsigned comment added by Skyyfaery777 (talk • contribs) 07:01, 16 July 2011 (UTC)

Transferred from Miscellaneous Desk. Richard Avery (talk) 07:15, 16 July 2011 (UTC)

Have you tried a different browser? General Rommel (talk) 09:54, 16 July 2011 (UTC)

Automatically copy from Firefox cache to a folder

While I am surfing the internet, I would like to be able to continuously save from the Firefox cache to a folder of my choice. Preferably I would like to be able to save only files with a particular extension, and be able to turn this continuous saving on or off. Although I have the add-on CacheViewer installed, you can only save files manually. I have been unable to find any other add-on that can do this.

What would be the easiest way to achieve this? I could probably learn to write something in Autohotkey or another simple BASIC-like language. More modern languages such as VBscript I find almost impossible to use. Would it for example be possible to run some other existing software, even while Firefox is running, which copies all the new files from the cache to my folder every second or so? 92.24.138.48 (talk) 15:43, 16 July 2011 (UTC)

How to copy and insert a "cookie" from a folder into Firefox?

I have various security programs which automatically delete all cookies. Rather than having to set my preferances for Google over and over again (for example turning off the dreaded "instant search"), I would like to save the cookie to a folder, and then when needed copy and insert this cookie into the appropiate place in Firefox. I once tried copying a cookie into Internet Explorer, but the computer would not let me do it. I would rather insert a cookie than adjust the settings of every security program, particularly as I would know what information Google was trying to hide in them, and in my experience several copies accumulate. I use WinXP. 92.28.255.228 (talk) 17:13, 16 July 2011 (UTC)

CookieCuller and OptimizeGoogle extensions can help some. ¦ Reisio (talk) 08:24, 17 July 2011 (UTC)

Thanks. Optimis/zeGoogle looks useful as it can turn off "Google Suggest" which apparantly stops the irritating habit of Google making wild guesses about what word you are beginning to type, and it can set some preferences without needing to keep a pernament cookie. The other add-on GoogleEnhancer does similar things, so together they give a lot of control. I've already got CookieCuller installed. 92.24.179.33 (talk) 09:38, 17 July 2011 (UTC)

Manually activating an on button

I have an old Dell laptop whose power switch broke that I'd like to turn on. I'd like to do that manually, maybe by soldering leads onto it myself and manually connecting them.

I've stripped back enough to see the circuit board connections. All of what I describe fits into about a 2 cm square so keep that in mind. There are 6 leads on the green board arranged in a rectangle pattern: 1 pair at the top/bottom, and then 2 more pairs on the sides. On top of that once sat (now removed) a small plastic device that has two horizontal wires that are visible. The top/bottom pair of wires were connected to this device. The two horizontal pairs went over this device and were bifurcated with this plastic square that seemed to be connected to the wire. In other words, when you pressed the power button, it would press these two horizontal pairs into the plastic device, which was connected to the vertical pair. That would complete a connection with all 6 leads to the circuit board.

My hunch is that the vertical pair of leads provides some power source, and pressing the power button depresses these two horizontal leads into the plastic thing, which simultaneously completes two connections. I also assume that the need for 2 power switch leads is because one detects a quick press and the other detects a longer "held down" press, for things like a hard shut down.

Incidentally the power switch is of a different style than other switches, like the volume switches, so I can't swap parts. I don't care enough to order new switches (although if I could pick something up from RadioShack I would) and the computer's not worth much, but I'm interested in how this works and would like to get it to turn on. Finally, any magic keyboard shortcuts that could bypass this process would be appreciated too. Thanks. Shadowjams (talk) 22:23, 16 July 2011 (UTC)

The leads were probably to an LED embedded inside the power button, which would light when the machine was on. Most modern PCB switches consist of a number of solder landing pads arranged in a geometric pattern. The underside of a button consists of a conductive elastomer (a black rubbery stuff) that (when the button is pushed) bridges some of the pads to others. You'll have to experiment to see which ones constitute the "before" and which the "after" pads. A more complex pattern (than just one before and one after) is sometimes used to handle pushes on the switch that aren't strictly vertical. If you were replacing the switch you'd probably need a "momentary" type switch. Note that, unless your laptop is exceedingly old, the power switch isn't anything really to do with the power circuit - it's just an ordinary signal-level circuit that's monitored by special logic in the southbridge. -- Finlay McWalter ☻ Talk 22:47, 16 July 2011 (UTC)

They're not LED leads... the button had no lights on it nor any nearby. The LEDs are elsewhere. As for age it's not extremely old. It's not a keyboard style rubber button. Its moving part was plastic that would depress the two horizontal leads into the plastic thing that was connected to the vertical leads. I know what kind of button you're talking about because that's basically what the other switches are, but this power switch is different. Shadowjams (talk) 05:07, 17 July 2011 (UTC)

Check eBay for a new switch. ---— Gadget850 (Ed) ^talk 14:23, 17 July 2011 (UTC)

July 17

Web site for selling diamonds

I find many web sites for buying diamonds, like this one: [7]. There you pick the parameters you want, then they sort through their DB and list those diamonds (with prices) which match your search criteria.

I want just the reverse, to list my diamonds and get quotes from multiple buyers. Is there such a site ? (I realize I could use a general auction site, like eBay, but would prefer a site specifically designed for diamond sales.) 68.79.93.3 (talk) 02:12, 17 July 2011 (UTC)

Okay, you've reached the limit here. You're not even sure that you have diamonds, and now you want to sell them on the web? Please take your stuff to somebody who is qualified to evaluate it, and come back when you have a meaningful question to ask. Looie496 (talk) 02:17, 17 July 2011 (UTC)

Personally I'd be pretty suspicious of any site that allowed you to do that. Who would buy gemstones from some random joe on the Internet? APL (talk) 02:28, 17 July 2011 (UTC)

I would expect them to be verified, at some point (although if they were certified, then this verification was already done beforehand). The point is to get an agreement that "if the diamond is as you say, then we will pay X for it". Note that there are sites where you describe your diamond and one buyer (who owns the site) will quote you a price. I just want the same thing with multiple buyers. 68.79.93.3 (talk) 02:55, 17 July 2011 (UTC)

You have many questions (e.g. here) about these diamonds that may after all not be diamonds. And "Give me advice to help me make as much money as possible" is an odd line of questioning for a "reference desk". Simple: donate the whole lot to charity. Then the charity has to figure out what to do with them, it gets the money, and you have the warm feeling that comes from financing something even more worthwhile than your average kickstarter project. You might even get a little tax break. -- Hoary (talk) 03:29, 17 July 2011 (UTC)

I will have them appraised (or even certified, if required), but would then like the option to sell them online. 68.79.93.3 (talk) 03:46, 17 July 2011 (UTC)

All right, let's return to your question I want just the reverse, to list my diamonds and get quotes from multiple buyers. Is there such a site ? (emphasis added). That appears to be a googling question, a diamonds question, or a selling stuff question. Try the "Miscellaneous" desk (or google). -- Hoary (talk) 04:45, 17 July 2011 (UTC)

I tried Google, but kept findings sites wanting to sell me diamonds, or sites wanting to buy diamonds, but only by a single buyer, versus multiple bidders. So, how would I do a Google search to exclude those ? 68.79.93.3 (talk) 08:07, 17 July 2011 (UTC)

APL, many stupid people have some money. Just think of the market for "generic" or "herbal" varieties of "Viagra", etc etc. Or the nitwits who pay a bit upfront for nonexistent Nigerian millions. -- Hoary (talk) 03:29, 17 July 2011 (UTC)

Many stupid people might have money at some point, but as you see they will have trouble keeping it, therefore, people with money tend to be those who can deal with it. — Preceding unsigned comment added by 88.8.79.148 (talk) 13:49, 17 July 2011 (UTC)

The answer to the original question is eBay, which because of the network effect contains the maximum number of buyers-of-diamonds-from-random-Joes-on-the-Internet you are likely to find. Comet Tuttle (talk) 04:18, 19 July 2011 (UTC)

Command Prompt problem

This is probably incredibly simple and I'm just missing something. I have three batch files: One "menu.bat" which prints a text file "menu.txt" displaying two options ("1" and "2"), and two other batch files, "1.bat" and "2.bat" (the options printed in menu.bat). Here's my question: I want to run menu.bat, but Command Prompt disappears as soon as I load it. What am I doing wrong? -- 68.0.166.142 (talk) 14:17, 17 July 2011 (UTC)

Do you open CP and run it or double click to run it? Does it contain an exit command? ---— Gadget850 (Ed) ^talk 14:21, 17 July 2011 (UTC)

I don't open CP and then run the command, I just want to be able to doubleclick the batch file and for CP to remain up so I can see menu.txt printed and respond to it ("1" and "2"). It does not contain an exit command. Unless you know of a way to load CP and automatically navigate to menu.bat? -- 68.0.166.142 (talk) 14:39, 17 July 2011 (UTC)

You can do that in several ways. Probably the most straightforward is to use the start command. You can read documentation by typing start /? in the command prompt, or at the Microsoft help website for Cmd.

You may also want to use the pause command at the end of your script, to hold a terminal open even if it has completed all its tasks. Nimur (talk) 16:05, 17 July 2011 (UTC)

The easiest way of achieving what you want is to use the /K switch, which treats the remainder of the line as a command to be executed without terminating the shell. Here's the .bat file:

@cmd /K type c:\yourpath\menu.txt

This script can be run by clicking its icon. The at-sign before cmd suppresses echoing of the command (so that you just see your menu, and not the command used for printing it). If your 1.bat and 2.bat are located in c:\yourpath, you may want to change to that directory first, like so:

@c:
@cd \yourpath
@cmd /K type c:\yourpath\menu.txt

--NorwegianBlue ^talk 20:33, 18 July 2011 (UTC) In the second example, it's not necessary to state the full path in the third line, @cmd /K type menu.txt is sufficient. --NorwegianBlue ^talk 20:41, 18 July 2011 (UTC)

Malicious program in my computer

I am only recently having a problem with editing WP (last few days), in that when I edit (hopefully it won't happen here), words like "P u r f u m e", etc. (here I intentionally separated each letter with a space) turn into a hyperlink to ads. They are the same blue color as WPs blue links, with a throbbing, dashed underline. It also tends to delete words such as other instances of the above example that are on the page, hyperlinking only the one remaining. I saved one edit by accident and had to revert myself, because it made these alterations I didn't mean to make. Has anyone had this problem; know how it can be removed from my computer? I have taken the steps of removing any recent software, applications and Windows updates with no effect, and Norton Anti-virus isn't picking it up as a virus. Any feedback would be appreciated, as this hampers my editing substantially here. (by the way, this hyperlinking effect goes on anywhere I go on the web - normally I just ignore it, but it makes editing WP sometimes impossible) This message originally posted at Wikipedia:Help desk#Malicious program in my computer Thanks, Hamamelis (talk) 17:09, 17 July 2011 (UTC)

You might give your system a Malwarebytes scan, for starters. ¦ Reisio (talk) 17:19, 17 July 2011 (UTC)

Thanks, I'm trying it now, Hamamelis (talk) 17:45, 17 July 2011 (UTC)

If that does not work, I would then try SUPERAntiSpyware, and after that Avast! which can do boot-time scans before the malware has loaded up. Then try some of these: http://www.techsupportalert.com/content/probably-best-free-security-list-world.htm In any case, cleaning out the garbage beforehand with Ccleaner should make the scans a little quicker. 2.97.209.26 (talk) 21:21, 17 July 2011 (UTC)

I appreciate all of your suggestions. Alas, to no avail so far. For some reason, I was not able to download Avast!, but I tried the rest; they certainly cleaned up a lot of junk, but not whatever this little bastard is. Doing some of my own research suggests this is something very new, that attaches itself to your registry (thus apparently cloaking itself from a lot of antivirus-, etc-ware). Manually trying out regedit, I was able to clean it up some (got rid of some old g a m e s and such, listed there but no longer on my PC), but I could not find the evil files I turned up in my research, which were blackice.exe, blackice.ini, etc. (files attached to something called "win32 maleware.gen"), but I think whatever I've caught is something like those/("it"). I'll watch here for a while for suggestions, and also to see if anyone else has a similar experience. Thanks again, Hamamelis (talk) 09:57, 19 July 2011 (UTC)

The next thing to do would be to create a HijackThis log and post it on one of the several forums that are dedicated to dealing with them, such as this one: http://www.bleepingcomputer.com/forums/forum22.html after following their instructions. I don't know why, but now the HijackThis download link redirects to something else - doubtless the forums can advise on where to get it from now.

Apart from that you could try running an anti-malware program in safe mode. I don't know if your computer would allow you to install Avast! in safe mode, but in any case you would need to un-install your existing anti-virus. If you want to do that I would download the Avast! instalation file, unplug your modem, uninstall your existing anti-virus, install Avast!, plug in your modem to allow it to update its files, then tell it to do a boot-time scan. I've also just found this http://forums.majorgeeks.com/showthread.php?t=35407 which may be worth looking at. 2.97.220.86 (talk) 18:11, 19 July 2011 (UTC)

Thanks a lot for the links and advice 2.97.220.86, will report back here sometime later (but I can't say when). Hamamelis (talk) 00:08, 20 July 2011 (UTC)

Multiplication and addition of arrays using foreach() loop in PHP

I would like to know the PHP code/program for multiplying and adding two 3x3 arrays using the foreach() loop. I've been trying to do it for days, but nothing seems to work. Somebody please help!!! I've tried the following code for adding the arrays:

<?php 
$a=array(1=>array(1,2,3),2=>array(4,5,6)); 
$b=array(1=>array(9,8,7),2=>array(6,5,4)); 
$c=array(); 
foreach($a as $v1) 
{  foreach($b as $v2)
{    $c=$v1+$v2;
}}
print_r($c);
?>

There are no errors, but it doesn't work,either. The output is incorrect. I don't know where I'm going wrong. If someone could tell me what to do, how to go about it,instead of giving me the code directly, that would do as well, just as long as I get to know how to do it. Thanks in advance! Zebec 21:12, 17 July 2011 (UTC)

You're still trying to add two array types together (both $v1 and $v2 are arrays in your loops). You cannot do that in PHP — it doesn't understand, and it just assigns $c to whatever the first array in your equation is. So the result you're getting, in the end, is the final instance of $a, every time, which is 4,5,6. If you are trying to make the internal values of the array add, you have to do another few foreach loops so that you're dealing with the values, and not arrays themselves. --Mr.98 (talk) 21:35, 17 July 2011 (UTC)

Here, also, is a re-written version of exactly what you have above. Note two things: 1. I've added some formatting which makes it clear what is going on (an absolutely essential programming habit!), and 2. I've added debugging calls so you can see, when you run it, what's going on. Both of these sorts of things are common when trying to figure out how a piece of code does or doesn't work.

<pre>
<?php 
$a = Array(
		1 => Array(1,2,3),
		2 => Array(4,5,6)
	); 
echo "a = ";
print_r($a);
echo "\n";
$b = Array(
	1 => Array(9,8,7),
	2 => Array(6,5,4)
	); 
echo "b = ";
print_r($b);
echo "\n";
$c=array(); 

foreach($a as $k1 => $v1) {  
	foreach($b as $k2 => $v2) {
		$c = $v1+$v2;
		echo "working on $k1:$k2\n";
		echo "v1 = ";
		print_r($v1);
		echo "\n";
		echo "v2 = ";
		print_r($v2);
		echo "\n";
		echo "c is currently = ";
		print_r($c);
		echo "\n";
	}
}

echo "c is finally = ";
print_r($c);
?>
</pre>

You can see pretty clearly what is and isn't happening that way. --Mr.98 (talk) 01:15, 18 July 2011 (UTC)

Do you realize that $c is going to be rewritten after each rendition of the inner loop?--v/r - TP 01:24, 18 July 2011 (UTC)

That's another good point! You're just assigning c again and again, rather than doing something like $c = $c + ($v1+$v2), or, in shorter code, $c+=$v1+$v2. Though that still won't work because of the array issue. --Mr.98 (talk) 15:35, 18 July 2011 (UTC)

Thank you very much Mr.98! I added a few more foreach loops so that the values would be used instead of the arrays, and also added the array_push function so that the sum gets stored in the third array, but because each of the two arrays require two foreach() loops, the third array is becoming longer than it should be. The order of nesting matters, I think, and I'm not able to figure it out. I also need to multiply two arrays in another program, which will be even more complicated. I can start work on that once I've finished this.

<?php
$a=array(1=>array(1,2,3),2=>array(4,5,6));
$b=array(1=>array(9,8,7),2=>array(6,5,4));
$c=array();
foreach($a as $v1)
{  foreach($b as $v2)
{    foreach($v1 as $c1)
{   foreach($v2 as $c2) 
 { $d=$c1+$c2;
    array_push($c,$d);
}}}}
print_r($c)
?>

Zebec 21:11, 18 July 2011 (UTC)

I'm still sort of unclear what you are trying to actually do with the arrays. Are you trying to do matrix addition? If so, I think you're going about it wrong. You don't need all of those foreachs. What you need, essentially is something like this: take element 1 of $a, element 2 of $b. Then iterate over the three values in them, adding each of them, and using them to create element 1 of $c. Then repeat for element 2 of $a, $b, and thus $c. $c would then be an array with two elements, which correspond to the additions of the two lines of $a and $b. I think your foreachs are causing you to do too many operations (4 when you should be doing 2). --Mr.98 (talk) 00:31, 19 July 2011 (UTC)

Yes,I am trying to do matrix addition. But the number of elements in $c will be the same as that of $a and $b. For example:

 
$a= 1 2 3 
    4 5 6
    7 8 9

$b=9 8 7
   6 5 4
   3 2 1

$c=$a+$b= 10 10 10
          10 10 10
          10 10 10

Hope you understand now. But, accessing one element of a 2D array like $a requires two foreach loops. Then how can I do it if I reduce the number of foreach loops? I know how to do it using for, but I need to do it with foreach. Zebec 20:16, 20 July 2011 (UTC)

Java functions

I am writing a function that I want to return an array of elements of different types. For example, I have a class called "cat" and I want to have a function that returns the cats age and whether it is declawed or not. Age is an integer and declawed is a boolean. I want my method to return both age and declawed in one method as an array. Do I use an ArrayList? How is that used?

    public String[] getAgeAndClaws() {
      String[] myInfo = {Integer.toString(age), declawed };
      return myInfo;
    }

This is what I have and I havent compiled it yet, but I dont think it'll work.--v/r - TP 23:52, 17 July 2011 (UTC)

I don't know if it's the best way, but you can do it with an ArrayList of Object, and then after you receive it from the method you cast each element, but you need to use Integer and Boolean since int and boolean are primitives (hence they don't inherit from Object) - frankie (talk) 00:38, 18 July 2011 (UTC)

    // at Cat class
    Integer age;
    Boolean declawed;
    
    public ArrayList<Object> getAgeAndClaws() {
        ArrayList<Object> catData = new ArrayList<Object>();
        catData.add(age);
        catData.add(declawed);
        return catData;
    }

    // then where you call it
    ArrayList<Object> catData = cat.getAgeAndClaws();
    Integer age = (Integer) catData.get(0);
    Boolean declawed = (Boolean) catData.get(1);

That works (I didn't post the code above; I believe it was frankie). To the OP: Is there some reason why implementing multiple methods, e.g., getAge(), getDeclawed(), getX(), is unacceptable? Using an ArrayList<Object> and then casting every call to its get() method makes me cringe because it throws type safety out the window, and you could easily trigger several ClassCastExceptions if you're not extra careful as you build on this code (I know it would happen to me!). Perhaps you could tell us more what you're planning to do and we could suggest an alternative.--el Aprel (^facta-_facienda) 03:34, 18 July 2011 (UTC)

The more I think about it, this is really what objects are for: holding values in memory and providing a useful set of methods for those values. You don't need to put the values into an array; just pass the instance of Cat to wherever you need it and call get() methods for whatever values you need.--el Aprel (^facta-_facienda)

I suppose, and I ended up doing it that way. The above was a homework assignment, and actually the requested code was not part of the instruction. I've been a programmer for 15 odd years and never bothered learning Java. The assignment used singular methods to get the information but I've done it this way in other languages before that were less type-sensetive. I appreciate all the help though.--v/r - TP 12:20, 18 July 2011 (UTC)

The problem is not that you have not learnt Java - actually you do not think in object-oriented terms, which is even worse. Give a look at this page, maybe it can help you.

By the way, I'm quite dubious about you having been a programmer for 15 years. Returning multiple values from a function is quite a bad idea, and it's widely considered bad practice in any language, even in C. --151.75.17.199 (talk) 23:34, 18 July 2011 (UTC)

Java and C don't support multiple return values, or provide a nice way to take them. This is certainly not universal. Many languages provide nice features to do this kind of thing. Paul (Stansifer) 08:19, 19 July 2011 (UTC)

Thanks IP. Actually, I have been programming for 7 years as a hobby and 7 years professionally amounting to 14 years or reasonably rounded to 15. PHP, ASP, ASP.NET, SQL (MSSQL, Oracle, and MySQL), VB6, VB.NET, Javascript, ActionScript 3. I've never had a problem returning multiple values from a function in languages that were less type-sensitive and I've never stumbled across anyone who considered it a bad idea. Your comment makes me question your credentials.--v/r - TP 14:34, 19 July 2011 (UTC)

July 18

Computers and ambient temperatures

Can today's desktop computers and flat-screen monitors operate safely and seamlessly in ambient temperatures between 80 and 100 degrees F? Is it ever dangerous (for the health of the computer and/or screen) to do so? Bielle (talk) 00:35, 18 July 2011 (UTC)

100 F is probably around the upper limits of what is advisable - My Acer netbook manual for example gives a maximum operating temperature of 35°C (95°F). I'd check the manual for your particular computer. If you have to routinely use it in these temperatures, I'd check that the cooling is working efficiently - vents not blocked, free of dust inside etc. With a laptop, the surface you put it on can make a difference too - something hard (so vents aren't blocked) that conducts heat well would be ideal. Your lap is ironically probably the worst place for a laptop in these conditions, and it may not be too comfortable either. AndyTheGrump (talk) 00:57, 18 July 2011 (UTC)

Hard drives will die earlier from excessive heat...unless you have a rugged computer, or custom cooling...you shouldn't run it at 100 degrees.Smallman12q (talk) 01:59, 18 July 2011 (UTC)

Erm, I ain't no physicist (as is probably obvious), but I think that link illustrates a flawed understanding of thermodynamics. To quote: "They [HD's] only consume around 10 or 12 watts under load, and around 7 watts at idle. But unlike your CPU, they're generating a lot of mechanical movement, which means friction-- and heat disproportionate to the power input". If they are generating more heat output than power input, we have a competitor for Andrea Rossi's Energy Catalyzer, and can build ourselves computers that actually push electricity (I said I wasn't a physicist) back into the mains socket. If they are consuming '10 or 12 watts', I'd hope that most of it is being converted into heat, as all the alternatives wouldn't do the computer and/or the user much good. AndyTheGrump (talk) 02:13, 18 July 2011 (UTC)

I think you just misunderstand his using of the word "disproportionate". I think what he means is that more energy per watt input is lost as heat by the hard drive than other computer components. -RunningOnBrains^(talk) 04:31, 18 July 2011 (UTC)

I don't think so. The comparison to the CPU suggests that he's very confused. He implies that the CPU is frictionless, or nearly so, and that it emits less heat in proportion to input power than the hard drive, both of which are completely wrong. -- BenRG (talk) 07:10, 18 July 2011 (UTC)

Neither the CPU nor the hard drive are doing any net work (they're not carrying water uphill or charging a battery), so 100% of the input energy ends up as heat. Also, Watts measure power, not energy. 130.76.64.121 (talk) 17:20, 18 July 2011 (UTC)

Actually one of the few relatively recent (2007) large scale public studies has suggested temperature isn't that big a factor within the first 3 or so years and also only at the extreme (e.g. 45 degrees C) [8]. Even the page you linked to talks about 45 degrees C. In other words, 100 degrees F should ambient temperature shouldn't have a massive effect on life span unless you have poor airflow. Decent airflow is obviously important under such ambient temperatures since you ideally want to keep the HDs under 45 degrees C. Incidentally that page seems a bit silly for reasons other then physics, you should always be worried about data loss no matter what your HDD temperature so should keep backups of important data. And BTW, people do use computers in countries where temperatures close to that range aren't uncommon and commonly they aren't rugged. If you're throwing your computer around or exposing it to sandstorms or rain or whatever then you may want one, but there's no reason to recommend it for 37 degrees C. Nil Einne (talk) 03:28, 18 July 2011 (UTC)

Thanks, folks. Well, there goes that argument for getting air conditioning. Sounds like the computer is more at risk from wildly shedding cat. Bielle (talk) 16:34, 18 July 2011 (UTC)

internet speed

hi,

i have always used torrents for downloading and uploading movies and tv shows, and was quite happy with the speed i got (200 kbps), but suddenly, a week back, the speed dropped to, like, 20, or sometimes, even 10. but when i download from megaupload or a normal download through my web browser (chrome), the speed is back at 200.

can anyone explain the drastic difference in speed?

thanx — Preceding unsigned comment added by 117.197.233.58 (talk) 03:47, 18 July 2011 (UTC)

It sounds like your Internet provider has probably implemented Traffic shaping and they're now limiting the speed of torrents. The only way to be sure is to literally ask them if this is the case, although if you haven't changed any hardware/software your side then it must be them though.  ZX81  ^talk 04:05, 18 July 2011 (UTC)

You might want to randomize the ports you're using, or switch clients. ¦ Reisio (talk) 03:23, 19 July 2011 (UTC)

Well, there is also the slight possibility that there aren't that many seeders with fast connections for a particular file the OP wants to download. Hence the slowdown. --Ouro (blah blah) 06:26, 19 July 2011 (UTC)

(Advanced networking) Bridging routers with multiple internet connections

Hi all. I saw the above (unanswered at the time of writing, doesn't bode well for getting an answer here!) question on extending a wireless internet connection with two routers. My question is related, but different. Imagine a situation where you have a row of houses, say...5. Every house has an internet connection and a router. Is it possible to bridge these all together, sharing the cumulative internet speed equally to any and all IP addresses given out? Assume for simplicity that each house uses a different provider and therefore aren't hogging the same bandwidth for that street. My limited knowledge of how these things work tells me that one router has to be "master" and all others are clients, so would that preclude the internet connection from the clients from being routed to the overall network? --Rixxin (talk) 16:04, 18 July 2011 (UTC)

At a theoretical level this is all perfectly possible. Professional network-grade switching and routing equipment has all kinds of high-capacity and high-availability features that allow channel bonding, dynamic trunking, adaptive load balancing and route failover. The path your packets take around your ISP's network, or around a large internet company like Google, or indeed over the public telephone network, can be through a varying network of fused and redundant connections, where switching equipment knowns about its peers and routes traffic intelligently. This kind of stuff is just what you'd expect from mainline equipment from Cisco, Nortel, Juniper, and the like. Whether it's a hierarchical scheme or not, or whether it's a master-slave scheme or not, is just a function of the inter-router protocols used. But things fall apart when people try to do this kind of stuff with the rinky dink home ADSL modem/routers they bought at Fry's for $60; building redundant channel-bonded failover networks isn't a feature that Linksys and Netgear and Belkin see as applicable for this market, so these products don't try to address this. -- Finlay McWalter ☻ Talk 16:39, 18 July 2011 (UTC)

computer makes continuous beeps before loading the bootloader, but my hardware seems fine?

I didn't know if I caught a virus while on spam patrol (I was vetting a known spamming IP's edits and the links they put up).

Basically the system (a Windows Vista) suddenly without warning started the soft shutdown process (i.e. windows closed one by one). When the system rebooted, the BIOS loaded fine and the power self-on test seemed to be okay -- no fatal errors by text, but when it starts time to load the bootloader it starts making very loud beeping noises.

I used a ubuntu flash drive (I also have ubuntu on the system) to try to diagnose the problem. I am going to try to change the default bootloader to Linux to see if it's merely a corrupted boot sector, but I've never had a problem like this before. I tried reinstalling grub (without changing configuration files) on the master boot record. This fixes the beeping problem, which makes me think it's a boot sector virus. However, grub won't load and the screen is blank. I can boot from the ubuntu flash drive successfully though, and it sees everything.

elle _{vécut heureuse} ^{à jamais} (be free) 17:46, 18 July 2011 (UTC)

converting mid to mp3 AND editing jpg photograph

I would be grateful if a user could please answer the following two questions. 1) how do I convert a song downloaded as mid to mp3? 2) how can I crop a photograph saved as jpg and also how can I enlarge it? Thank you.Simonschaim (talk) —Preceding undated comment added 18:39, 18 July 2011 (UTC).

For 2) Irfanview. 92.28.249.93 (talk) 20:22, 18 July 2011 (UTC)

For 1) use TiMidity++ to render MIDI to WAV, and then Audacity (or lots of other things) to convert the WAV to MP3. For the first part, at the command line, you do something like:

timidity foo.mid -Ow which will create foo.wav

-- Finlay McWalter ☻ Talk 21:11, 18 July 2011 (UTC)

Thank you Finlay McWalter. I found your information very helpful. Simonschaim (talk) —Preceding undated comment added 14:35, 19 July 2011 (UTC).

July 19

torrent speed

when i started downloading lost season 3, the speed was like 150 kbps. when it was 25% done, i ended the session. but the next day when i resumed, the speed dropped to 10-20 kbps, or even 5.... and it's still going on... (this is the 3rd day; on my normal speed, the download would have finished by now)

can anyone tell me why? is there something wrong with my torrent or my internet connection? — Preceding unsigned comment added by 117.197.247.76 (talk) 01:21, 19 July 2011 (UTC)

You already asked this question recently; look a little up the page for the answers to it. --Mr.98 (talk) 01:44, 19 July 2011 (UTC)

Cheat sheet program

What program could be used to create documents such as this or this? I can't get Word to do that, and although I could write a GUI in Java, with all sorts of JPanels, there's hopefully a better way. Any thoughts? KyuubiSeal (talk) 05:39, 19 July 2011 (UTC)

Inkscape, or HTML/CSS ¦ Reisio (talk) 06:48, 19 July 2011 (UTC)

Doing this in a word processor isn't difficult. Just create a table and merge-cells as needed, and (for one that resembles the HTML cheatsheet) turn off the borders for cells. The only thing that you might not be able to trivially do is the gradient fills in the Jquery sheet (I don't have a recent version of Word; OpenOffice-Write doesn't do gradients for this). Or you could easily do this with HTML+CSS (gradients too). -- Finlay McWalter ☻ Talk 13:28, 19 July 2011 (UTC)

Oh, darn. I completely forgot about merging cells. The sheet I'm writing is on HTML, so I could do it that way too. Thanks! KyuubiSeal (talk) 14:53, 19 July 2011 (UTC)

Computer attempts to boot, fails, and repeats until unplugged.

Not long ago while plugging in my iPod, I noticed my computer seemed to have electricity running through it (where it's not supposed to run). My hand would feel weird, and start to tingle and then hurt when I touched any metal part on the case, I immediately turned off the computer, unplugged it, took it off the ground, and left it alone for a few days. I came back, opened it up, and made sure my motherboard was properly secured, I determined it was, and that there were no foreign artifacts laying around, closed it up, made sure it was still un-grounded, and attempted to boot it up. It turns on, the fans start spinning, the screen stays black, and then it turns off abruptly. It then, without any user input, attempts to start up again. This repeats until the power cord is unplugged.

I troubleshooted it by taking out parts individually. First the DVD drive, no luck, then the RAM, still no boot, then the Graphics Card, still nothing, finally I removed the heat sink and processor and it finally booted up (as much as it could).

Any ideas as to what could be wrong with it OTHER than the processor? I'm really not looking forward to shelling out a few hundred dollars for a new one.

Regards, EvlD — Preceding unsigned comment added by 76.7.238.176 (talk) 07:18, 19 July 2011 (UTC)

I have no idea what's happening, but my first instinct is that the case is faulty. General Rommel (talk) 08:28, 19 July 2011 (UTC)

It sounds very much like a faulty power supply. These are easily replaced by someone who knows what they are doing, but as General Rommel suggests above, you should first check that the incoming connection is not shorting to the case. Dbfirs 09:25, 19 July 2011 (UTC)

(edit conflict)The "my computer seemed to have electricity running through it" may be the key. If the mains voltage is leaking to the case it could, potentially, be dangerous. ☠ Caution is advised!

If the power supply is faulty that may well explain the "boot up, boot fail, restart loop" the OP is experiencing. (I recall I had a motherboard that had a BIOS setting that caused it to automatically restart after a power failure.)

It was a possibilty that a component had failed causing excessive current drain that might cause the power supply to shut down and re-start. N.b. A PC cannot boot while the RAM is removed!

If possible try another power supply. Or try adding components one by one to see if it causes a failure.

Here are a few links to tech help forums for "computer constant reboot" as the topic: computing.net, techsupportforum.com, certforums.co.uk, and whirlpool.net.au.
As for the final question, the Motherboard itself could be faulty. In the forums it was found that faulty reset switches and evan a HDD LED cable were the problem. - 220.101 talk^\Contribs 09:50, 19 July 2011 (UTC)

Program takes eons to load

I'm trying to use VLC player to stream TV over the local network (that's a whole different set of problems) but it takes upwards of 10 minutes before VLC actually loads/opens from the moment when I click on it. Had a google but no real ideas, thought maybe it was something to do with the new antivirus I just installed, Viper --131.172.80.142 (talk) 09:32, 19 July 2011 (UTC)

...well if you disable the A/V temporarily, you'd know. Alternatively, check how much RAM you have. ¦ Reisio (talk) 18:31, 19 July 2011 (UTC)

PHP

Can I use PHP to create web-based computer algebra systems? 474,456,499 24,485,729 14,939,942 11:37, 19 July 2011 (UTC) (Please answer on my talk page)

Yes. You have one page in which a person enters the data. Then, that page sends the data to the server. On the server, PHP is used to do the calculations. Then, the results are sent back as a new page. If you don't include AJAX, you are limited by using an input-response program. With AJAX, you can use an event-reaction based program. -- kainaw™ 16:10, 19 July 2011 (UTC)

Doing it all entirely in JavaScript is also possible. ¦ Reisio (talk) 18:32, 19 July 2011 (UTC)

Some time ago I created a fairly trivial PHP front-end to the GNU Octave command line. You can download a symbolic algebra system for Octave, and then drive it through a similar web-based PHP interface. All you really need to do is have your PHP program send input and receive output from a command-line.

If you prefer, you can use PHP to drive another computer-algebra system, or try to design your own symbolic representation system yourself, implemented in PHP. Nimur (talk) 21:33, 19 July 2011 (UTC)

PC to TV with HDMI/DVI-D

Hi, I'm wondering if someone can help, I've just got a new LCD tv and I'm trying to hook the PC up to it. I've connected a HDMI to DVI-D (dual link) cable (hdmi at tv side) and a single 3.5mm audio cable between them & there is a picture, but when I try to watch an avi file (using Nero showtime) both the tv & PC pictures go all blocky. When I unplug the cable the blockyness goes away. When I'm not playing a video file the pc picture displays on the tv clearly. Can anyone give me some advice? I'm thinking it must be an issue with the cable (too long? it's 5m, interference?) rather than the graphics card as video plays ok on the pc itself. Thanks AllanHainey (talk) 18:39, 19 July 2011 (UTC)

Blocky artifacts are often a symptom of a computer that is too slow. To be more technical, it means that frame output took place before video decompression was completed. If your graphics card (or computer CPU) can only marginally decode the video when one screen is hooked up, the addition of a second screen (your television) may push the system to its capacity - you may be out of video RAM, or may simply not have enough cycles on your GPU or CPU to produce output for both screens and decode the video at a high frame-rate.

If the issue is visible only with large (high-quality) files, but goes away when you play smaller (low-quality) files, that almost certainly confirms this diagnosis. Consider upgrading to a more powerful graphics card (or CPU) that has better support for dual-display. Nimur (talk) 19:05, 19 July 2011 (UTC)

Thanks, I'll hunt down a small low quality video file to check if there's the same issue & try it with the computer screen unplugged too. Out of interest is there a way to determine whether its a graphics card or CPU issue? - like knowing GPU of X spec can handle up to Y Mb video files?. I'd hate to get a new graphics card & find out it was a too slow CPU. As a related issue where would I check the spec of the graphics card I have installed? AllanHainey (talk) 20:24, 19 July 2011 (UTC)

Video codecs are a little bit "voodoo-esque" - so there's not a straightforward mapping of GPU performance to video-playback-capability. But the thing you want to look at is bitrate, not file size directly. You can also consider installing a better or newer version of your codec: I highly recommend the ffmpeg suite, or ffdshow on Windows. Both are free software and are very high-performance, hardware-accelerated implementations of the standard video and audio codecs in use today. If you use the VLC player, you are already using ffmpeg under the hood. (Installing VLC is a pretty easy fix for many users: download it from the official website). If the video plays "fine" in VLC, but not in other video players, consider switching (or consider instructing your existing video-players to use ffmpeg, by installing the DirectShow filters in FFDSHOW).

The trick is that the performance depends on many many factors. The most important factors are the input (compressed) bitstream bitrate; the output (uncompressed) video size; and the number of encoding features in use (motion vectors, block comparisons, and so on). Each of those parameters were decided by whoever created the video file, and were tuned for file-size, performance, and image quality on the creator's machine. You can use ffmpeg to perform video codestream analysis, but this is a bit more technical than most users want to get. What you really want to determine is (1) whether you can, on average, decode each full frame faster than you need to display it on screen; and (2) what behavior your codec (and video player software) prefer to use if you can't meet that requirement (a dropped frame): the frame can be dropped entirely (all processing on it is stopped, leaving behind the last frame that completed, or a blank screen); or the frame can be rendered before it's ready (resulting in any number of weird-looking images, the least of which include blocky-artifacts).

You can get some ballpark comparative numbers for different hardware configurations from these video and image-processing benchmarks: CPU Core Performance and Graphics Card Performance benchmarks from last month at Tom's Hardware. In some unusual circumstances, your video playback performance may also be limited by main memory (total amount of RAM on your computer); or by hard-disk speed; but those are not commonly the most serious bottleneck on a modern computer. Nimur (talk) 21:12, 19 July 2011 (UTC)

What CPU load does Task Manager report? CS Miller (talk) 11:43, 20 July 2011 (UTC)

Agree if VLC does not "fix" it your computer is too slow, I had same problem using a dual core windows 7 laptop 4GB RAM etc etc pluged into a giant LCD TV; the came-with-it Cyberpathic DVD s/w was a pig but VLC just played those DVD. But nah a dedicated DVD player is almost free and the TV has a USB port for memory sticks, the laptop is now back on my lap! 81.109.247.189 (talk) 22:35, 19 July 2011 (UTC)

Could it be that the TV doesn't support HDCP? If a HDMI source is connected to a DVI-D display, then it is unlikely that HDCP can be established. The program is then informed of this, and can decide not to display the picture, or only display a degraded version of it. CS Miller (talk) 11:43, 20 July 2011 (UTC)

Bytes free on a Commodore 64

The start-up screen of a Commodore 64 says:

    **** COMMODORE 64 BASIC V2 ****

 64K RAM SYSTEM  38911 BASIC BYTES FREE

READY.

The READY. message comes from the BASIC interpreter, everything before that is a start-up message text. However, when I have done a thorough memory search of the Commodore 64 (by using a loop that PEEKs at every single memory location) I have only found the "**** COMMODORE 64 BASIC V2 ****", "64K RAM SYSTEM" and "BASIC BYTES FREE" bits. Therefore the number 38911 has to be dynamically calculated. But on every single Commodore 64 that I have used, it has always been the same. The Commodore 64 doesn't even use the nowadays ubiquitous method of allocating memory dynamically, instead its memory map is fixed. Has there ever been a case where the computer has reported some other number than 38911 as the number of free BASIC bytes on start-up? JIP | Talk 19:03, 19 July 2011 (UTC)

The number doesn't necessarily have to be dynamically calculated, it could be hard-coded as a constant. The source code for BASIC interpreters in those days was written in assembly language, and disassembled versions can be found here and there, so in principle it would be possible to figure out how it worked. Looie496 (talk) 19:26, 19 July 2011 (UTC)

(From my very faulty old memory...) When the system loads, it places the main system at the top of RAM. So, the memory pointer begins at the end of the entire 64k. It decrements as memory is filled with all the background operating stuff. When it is done, it shows where the memory pointer is - which happens to be how much memory is available. If you have faulty memory, you will see something different. That was rare, but I saw it happen to one (and only one) C64. It reported 0 basic bytes free. It was possible to change how many bytes were free by using the cartridge, which could be directly mapped to RAM. An example is Simons' BASIC. (cool - there's and article with a screenshot of the altered basic bytes free!) -- kainaw™ 19:35, 19 July 2011 (UTC)

This may interest you: http://www.pagetable.com/?p=48 2.97.220.86 (talk) 19:49, 19 July 2011 (UTC)

Here are some more details, sure to be either boring or delightful depending on where the C=64 fits on your nostalgia scale:

It's done in 2 layers: first, a probe by the kernal to determine the usable RAM area, and second, the BASIC interpreter deciding to all of it, minus one byte. Note that the 38911 byte BASIC program area is just the largest contiguous chunk of free memory. There is another fairly large unused area of 4096 bytes starting at $C000, between the BASIC ROM and the device I/O ports. That's a good place to store stuff that needs to coexist with a BASIC program, since BASIC won't mess with it.

$FD50 is the early kernal routine that scans memory, starting from $0400 (it scans upward, not downward as Kainaw said). It writes $55 then $AA to each address, reading them back to make sure the write was successful, and stopping when an unwritable address is found. The unwritable address (normally $A000, the first byte of the BASIC ROM) is recorded at $0283, the "top of memory" pointer. There's also a "bottom of memory" pointer at $0281, which gets set to a hardcoded $0800. (The memory from $0400 to $07FF is used as video RAM in the default text mode so it's effectively unusable for other purposes.)

Later, the BASIC setup routine $E3BF queries the kernal for the top and bottom of memory (by calling $FF9C and $FF99) and copies the "bottom of memory" pointer to $2B and the "top of memory" pointer to $37. It increments $2B, making it $0801, and stores a zero byte at $0800. The single zero byte at $0800 is important somehow... if you change it, BASIC gets confused. I don't know exactly why.

After the setup is done, the routine at $E422 prints the startup message. To compute the number before "BASIC BYTES FREE" it subtracts the value at $37 from the value at $2B. In the normal situation, that's $A000 - $0801 = $97FF = 38911. 67.162.90.113 (talk) 21:13, 19 July 2011 (UTC)

A cartridge can contain a ROM which is mapped at $8000-$9FFF, which will overlay (for reads) the RAM normally present there; the write-and-readback on an address confirms that it's not overlaid. There's usable RAM under the BASIC ROM too (and, academically, under KERNAL). The ROM overlays can be switched in or out with pullups on the HIRAM and LORAM lines on the cartridge port. I don't think there's a definitive way to detect (in software) a cartridge (except that, for it to hook the kernal it needs to have a signature at $8004), so kernal needs to check at least the cartridge-rom and basic-rom spaces to see if they're overlaid in the current memory map). But a scan from $0400 is more thorough than that needs (a simple read/invert/write/read at $8000 and again at $A000 would be sufficient). I can't help wonder that, rather than Kainaw's bad-memory theory, it's a holdover from the VIC-20, which could contain a variety of different RAM sizes depending on expansion cards. -- Finlay McWalter ☻ Talk 22:16, 19 July 2011 (UTC)

Indeed, the scan, and the 64's rather bonkers memory map (all that lovely space at $C000 gone to waste) makes a lot of sense if you imagine that, while they were designing the C=64, maybe they were considering selling a cheaper "Commodore 32" (the same machine but with the two high RAM chips missing). Even in a C=32 the CART-ROM, BASIC-ROM, VIC-IO, SID-IO, CIA-IO, CHAR-ROM, and KERNEL-ROM images would all be at the same place; the only change would be that they would need to move the colour-RAM from $D800 (which is a VIC register setting). I stress I've no evidence that a C=32 was ever countenanced, but back in them days when 32k of RAM cost an appreciable sum, having an option for that would make sense. -- Finlay McWalter ☻ Talk 22:36, 19 July 2011 (UTC)

I want to keep bookmarks, but not have them pop up in Google chrome's autocomplete?

Is there any way? I want them organised in neat folders for research but I don't want them interfering with my search results. elle _{vécut heureuse} ^{à jamais} (be free) 22:41, 19 July 2011 (UTC)

In Firefox, you can use bookmarks but disable the "smart completion" in the URL bar by setting the MaxRichResults parameter to -1. I do not think there is an equivalent option in Chrome, by design: Google intends for Chrome to assist you in finding the page you are looking for. Here is some more information specific to Chrome: Predictions in the address bar, and some information for disabling some parts of the prediction service. Nimur (talk) 00:47, 20 July 2011 (UTC)

I'll check that out, but it probably won't solve my problem. Thanks anyway! elle _{vécut heureuse} ^{à jamais} (be free) 07:28, 20 July 2011 (UTC)

July 20

Programming in MS Visual Basic

Can you do it without buying expensive tools? — Preceding unsigned comment added by 88.8.79.148 (talk) 00:56, 20 July 2011 (UTC)

Visual Studio Express is available at no cost. Products for all of the Microsoft development infrastructure are available at http://www.microsoft.com/express - including Visual Basic Express. All of the Microsoft Developer Network tutorials, API documentation, and information are available for no charge at http://technet.microsoft.com and at MSDN.microsoft.com. The official Microsoft Visual Basic Developer Center contains a lot of getting-started guides, tutorials, and technical notes. Nimur (talk) 02:49, 20 July 2011 (UTC)

If you want to try it on linux, you need something called Mono (software) for .NET Framework.[9] I kid you not. 99.2.148.119 (talk) 04:15, 20 July 2011 (UTC)

You'd be better off learning C or Perl and using a free text editor and compiler. ¦ Reisio (talk) 05:20, 20 July 2011 (UTC)

The OP specifically asked about programming in VB, so why should you assume he'd be "better off" doing something else? AndrewWTaylor (talk) 09:47, 20 July 2011 (UTC)

Is it possible to fool installer programs into thinking you have admin access?

I know some installer programs call for admin access (and will shutdown without it) when their program has no need to be administrator. According to this video [10] by recompiling the installer code I can eliminate this requirement, but are there any other ways? 128.143.175.123 (talk) 04:26, 20 July 2011 (UTC)

This doesn't answer your question but is relevant to what you're trying to do; you could try using Universal Extractor to simply extract the program from the installer. This should work for programs that do not require registry changes and special drivers to be installed. AvrillirvA (talk) 10:47, 20 July 2011 (UTC)

how does a computer decide to allocate computations to a graphics card?

I've tried googling this (howstuffworks yay) -- but I am still rather confused. Does the main CPU simply say, "oh look here is some information that looks like vector information! I'm sending it over to the GPU?" If I make a graphically intense program, with my draw functions and so forth, I'm guessing I am using libraries that explicitly makes calls to a graphics card? I notice that say if a dedicated graphics card is absent, the CPU can do the task anyway. It's bad at it -- but it can still do it. elle _{vécut heureuse} ^{à jamais} (be free) 07:30, 20 July 2011 (UTC)

A programmer explicitly instructs the program that certain functions will execute on the graphics card. In the case of a modern GPGPU, using a programming environment like CUDA or OpenCL, here's the general process:

• A special set of instructions are written using a specialized programming language (CUDA or OpenCL)
• A special compiler is used to convert that into machine code for the GPU (not for the CPU)
• A specialized linker with knowledge of the graphics device driver is used to cross-link the GPU code with a standard (e.g., x86) program.

At the lowest level, the way this works is with memory mapped I/O. A programmer who has access to the spec-sheet for your CPU, your motherboard, and your graphics bus writes a special C program that gets compiled using a driver development kit (in other words, a compiler who produces privileged code that has unprotected access to machine IO and memory, in a way specific to your operating system). By writing values to certain memory locations, the graphics bus communicates the GPU program to the graphics memory and triggers a start-of-execution.

In the case of graphical (non-GPGPU) programming, all of the above is generally true; simply replace "CUDA" or "OpenCL" with "DirectX" or "OpenGL." As before, the programmer writes code in a slightly modified variant of the C language, then compiles it and links it against the device-driver and the host executable that runs on the CPU.

Today's technology is not able to automatically detect that certain code is vectorizable and "decide" to run it on the GPU automatically. However, at compile-time, certain compilers can auto-vectorize to take advantage of SSE, multiple cores, or other vector instructions if they are built onto your CPU. On many modern CPUs, that type of vectorization can even be determined at runtime, using advanced out of order execution and similar runtime code reorganizations/equivalent-code-substitution. Nimur (talk) 11:33, 20 July 2011 (UTC)

I guess I should have mentioned: if you use a graphics library function, or a GPGPU library function, then all of the above work was already done for you by another software programmer; but at some level, somebody had to write the code and the commands to explicitly invoke the GPU. For example, every time you write a "draw line" call, or a "rotate and scale texture and render it to screen" function, the library is delegating that to a pre-built graphics routine that manages memory transfer and GPU instructions.

The onus is on you, the user of a graphical drawing library, to learn whether the library uses the GPU, uses the CPU, or makes an intelligent decision at run-time to select hardware- or software-rendering. Such a detail should be clear from the library's documentation. Nimur (talk) 11:43, 20 July 2011 (UTC)

Thanks so much! Last question: say a dedicated graphics card is absent, and we have to use that awful onboard integrated video card. I know awful performance is a given, but what exactly happens in that scenario, as far as instruction passing goes? elle _{vécut heureuse} ^{à jamais} (be free) 19:58, 20 July 2011 (UTC)

Missing burner registry entries

I believe after I installed Nero 6, my iTunes started complaining of missing registry entries for burning, and said I should reinstall. I held off on it because iTunes takes an eternity to install these days, but a week or two later when I did reinstall, it didn't help. No burner programs are working. Is there any advice from the help desk on how to fix this? Mxvxnyxvxn (talk) 13:06, 20 July 2011 (UTC)

It sounds a lot like a problem with the filters settings in the registry, take a look at the Microsoft article here for more information and the changes you need to make to the registry to fix it (Make sure you reboot after changing them). Hope this helps!  ZX81  ^talk 13:29, 20 July 2011 (UTC)

Tried it, it's still not working. Mxvxnyxvxn (talk) 13:45, 20 July 2011 (UTC)

"what was the last city you logged in from???"

When I tried to log into Google's gmail, it asked me for either the answer to my security question, or WHAT THE LAST CITY WAS THAT I LOGGED IN FROM! Can anyone find any evidence of Google asking specifically the latter question, or was this a phishing (or man in the middle) attack, where it wasn't really Google? I've fallen for a fake paypal message in the past and had my account cleared. This time I just gave the "last city" answer, if it wasn't Google, I can't imagine how anyone could misuse that... Did I do wrong? Thanks... 14:11, 20 July 2011 (UTC) — Preceding unsigned comment added by 188.36.85.63 (talk)

Have you been logging into gmail from lots of different computers? I once tried to log into gmail from a library computer and it asked me for a mobile phone number to send a text message to "verify" my account. Since I don't have a mobile phone that was pretty much the end of that account and all the messages in it. My advice; don't trust google. Have a backup account, have accounts with other providers like yahoo and aol, and keep local copies of your important emails 82.43.90.27 (talk) 14:14, 20 July 2011 (UTC)

Yeah I know about "send to mobile", but my quesiton is about the cities - is there any evidence in any forum online that Google actually does that?? Or was it a phisher?? Yeah, I did log in from different cities in different countries, but in order for it to be real, it has to actually be something Google does - which would have evidence on the net or in forums! So, can anyone find anything like that? Does Google do this?--188.36.85.63 (talk) 14:45, 20 July 2011 (UTC)

I've had it before although it also gave the option to answer the secret question which I chose instead. The best way to avoid phising is to be careful what you visit as a smart phiser (most not bothering) will just replicate what the site actual does meaning knowing what the site actual does and does not do is often not very useful. In particular if you want to visit Google or Paypal or whatever, type in the address yourself and make sure you visit the secure (https) site and check the certificate when it's likely to be needed (although realisticly your browser should warn you). Doesn't trust other sites and particularly not links in email or IM to take you to Google or Paypal. Nil Einne (talk) 18:35, 20 July 2011 (UTC)

Question about a certain kind of URL

Sometimes, I get URLs with very long strings of characters. For example, the CASSI result for Journal of Biological Chemistry is hosted at

• http://cassi.cas.org/publication.jsp?P=DXaT8ZV7yNcyz133K_ll3zLPXfcr-WXfc-eO0t37Of0yz133K_ll3zLPXfcr-WXf-9sRQmIIxJMyz133K_ll3zLPXfcr-WXfw9Ii__qPrXffzKcm8PwFCg

Now there's just no way this has been decided manually, so what exactly am I looking at here? How was it built? Is there a way to "decode" the url? Headbomb {talk / contribs / physics / books} 16:35, 20 July 2011 (UTC)

They just took whatever info you submitted and encoded it as a string. This is usually called serializing. You deserialize or unserialize to get the original information back. There are many methods for serializing, so it is rather difficult to know exactly what method was used. However, you can see that it contains some repetition that may expose the method. -- kainaw™ 16:58, 20 July 2011 (UTC)

To try to determine the type of encoding, I did some simple differential analysis. Comparing the results when one searches for 'aaa' vs 'aab' one sees the two strings are almost identical, except for 11 characters after "WXf". As this single bit change in the input changes all 11 output characters (an avalanche effect) it's likely that these 11 characters are a diffuse function of "aaa" etc. I don't know what this function will be, but it's likely something like an md5-hash, truncated, and encoded with something like radix64. -- Finlay McWalter ☻ Talk 17:30, 20 July 2011 (UTC)

A hash function is a one-way function. That is useless for this purpose. This is a serialization function because it must be two-way. You go one way to turn the user input into a string of characters. You go the other way to turn those characters into the original data. -- kainaw™ 19:25, 20 July 2011 (UTC)

Hmm.... well alternatively, is there a way to somehow crack the CASSI search engine? I'm selecting "CODEN" and search for "JBCHA3" to get the above string. (The end goal is to have a template that links to the CODEN result from CASSI, based on the CODEN itself, similar to ISSN 0123-4567 generated from {{ISSN|0123-4567}}.) Headbomb {talk / contribs / physics / books} 17:22, 20 July 2011 (UTC)

User-friendly tools to change MAC addresses?

With the recent political prosecution of Aaron Swartz falling close on the heels of the prosecution of a number of luckless teenagers who Wi-Fied to the LOIC website and pressed the button for Anonymous, it sounds like the abuse of MAC addresses for Big Brother purposes has hit the big time. And some years ago I remember reading that IPv6 was going to make them public on every packet of data transmitted anywhere on the Internet! So it seems like the general public needs a lot better tools than the semi-literate instructions in "MAC spoofing" (note: I'm not discussing actual spoofing; merely reliable randomization to protect privacy). Has anyone developed user friendly tools, for example for the typical PC user to ensure that a fresh MAC address is automatically generated each time it is powered up? Wnt (talk) 19:01, 20 July 2011 (UTC)

What exactly do you want? On most POSIX computers that have an ifconfig utility mechanism, setting the hardware's reported MAC address is trivial: simply edit the network interface configuration file /etc/network/interfaces/ and add a line, hwaddress ether 01:02:03:04:05:06. To do so from a GUI application is trivial; I can write a Java application in about three or ten lines that will display a "GO" button and run a script to do so. But, this only works if your network interface supports software-specified MAC addresses.

On a Windows computer, there is already a graphical utility, called the Control Panel, that allows you to graphically edit your network interface MAC address. As before, this only works if your network interface supports software-specified MAC addresses. (Here are detailed instructions from Microsoft to configure your network adapter's settings).

I think you are pre-supposing that a GUI will make this technical-process easy for non-technical users. While it may turn the operation into a one-click "GO" button, it has not simplified the decision-making stages: the user must still know how, why, and when to alter their MAC address; and the user must also profess the level of competence to verify the change, and establish whether the change was sufficient to anonymize their network-transactions, without breaking it. It is these followup steps that require technical proficiency, not the simple act of resetting the MAC address.

As a last note, you can not change your MAC address "any time you feel like it" and expect zero network side-effects. If you control your own ethernet link, you may be able to get by without any noticeable problem, but you seem to be misunderstanding the purpose of a MAC Address. It is part of the routing stack; it merely resides below the IP layer. Changing the MAC address at random will cause difficulty in the assignment and persistence of a DHCP address, for example. If you are connected to a link with a high volume of systems, all who randomize their MAC addresses very often, you will quickly be unable to receive an IP address, and will be unable to connect.

All that was rather long. Let me summarize this in one line: randomizing your MAC does not guarantee anonymity, so providing a trivially-simple user-interface would only serve to mislead non-technical users about the complexity of computer-networking. Nimur (talk) 19:44, 20 July 2011 (UTC)

I went through Device Manager and I don't see any obvious six-byte numbers. There are a tremendous number of 'details' and a whole lot of numbers but not those that I can see. The article suggested it was necessary to do other things like edit the registry to change this, which strikes me as a less than desirable alternative.

I understand that it's part of the routing, but my assumption (am I wrong?) is that if you change a MAC address, then connect the computer to a new Ethernet plug or Wi-Fi network it's never been on before, there will be no ill effects. What I'm not clear about is whether there are other numbers being released that compromise anonymity - but the goal of any user friendly app would not be to guarantee anonymity overall, but just to guarantee the MAC address was no longer a useful tool to any attacker. Wnt (talk) 20:14, 20 July 2011 (UTC)

Windows thinks my hardware has changed, but it has not.

I have WinXP sp3. I do not have Windows Update running automatically, but go to its website from time to time. The last time I did that, yesterday, it downloaded quite a lot, about eight or nine updates. I also installed two or three programs since then. I used the Windows Clean Up option, and it compressed about twenty times as much material as it usually does. When I went to a computer forum (not sure if I did this before or after the Clean Up), I had difficulty closing the Firefox page and a lot seemed to be being downloaded, so I right-clicked on the "two computers" icon on the bottom right of the screen and chose disable. The icon disapeared.

I restarted my computer to restore this icon, but I got something coming up saying that a lot of hardware on my computer had changed and I needed to re-activate Windows. But no hardware has changed, apart from my changing a DVD drive around a year ago. I restarted my computer, same thing. I used a System Restore point from two days ago, same problem.

Windows says I've got THREE days to re-activate my computer - not the THIRTY days I've seen mentioned on the internet for this problem. I went to Windows Update again to see if this was a known problem. Something about "Windows genuine advantage" came up and I ran it - I remember running it long ago without any problem. It told me to buy Windows 7, which I don't want. It would not let me check for any updates.

I have an old 2nd hand computer. It does not have any disks. I have found the MS sticker on it with a OEM product code on it. It has been working happily without these problems for one or two years. I recall I did the verification for "Windows Genuine Advantage" succesfully in the past.

What has gone wrong? What can I do to fix this? I'd rather get WinXP running again rather than having a sudden forced switch to Ubuntu. 92.24.187.93 (talk) 19:23, 20 July 2011 (UTC)

Sorry that'll this sound a bit obvious, but have you just tried reactivating it? (you didn't actually say). The same thing that's telling you to reactivate will also give you instructions on how to do this. The easiest way to do this is just to let it do it automatically via the Internet, but there's an phone option as well. However, you said about you found the sticker with the OEM code on it, so is it not stuck to the computer? OEM licence codes SHOULD be stuck to the computer as they aren't transferrable to another machine so I have to ask was it originally from another computer? (or just simply that the original person who built and initially installed the computer neglected to stick it to the machine?).  ZX81  ^talk 20:09, 20 July 2011 (UTC)

The sticker was stuck to the machine, I did not notice it at first as my scanner was on top of it. I'm puzzled why it says I only have three days to activate, not the thirty days that seems to be standard. I'm wondering if some malware is the cause of this. 92.23.36.253 (talk) 20:17, 20 July 2011 (UTC)

Wiping clean an iPhone

Resolved

My wife has just sold her old iPhone but she wants to wipe clean its memory before handing it over. Any thoughts on how to do that? AndyJones (talk) 19:28, 20 July 2011 (UTC)

Here is detailed information from the official Apple help site: iOS: Understanding 'Erase All Content and Settings' . You can also take the device to an Apple retail store for assistance. If you don't currently have the device in your possession, but you set up the Find My iPhone application, you can also cleanly wipe the entire device using Find My iPhone's remote-wipe tool. Nimur (talk) 19:37, 20 July 2011 (UTC)

Hello, you can try this: On your iPhone, go to "Settings", then go to "General", and there should be an option that says "Erase All Contents and Settings". You can try looking here or go to Apple's Support Page for more information on wiping your iPhone before re-selling it. -- Luke ^Talk 19:39, 20 July 2011 (UTC)

Great advice, thank you! AndyJones (talk) 19:57, 20 July 2011 (UTC)