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May 11

Desktop backgrounds...(A more convenient way to switch them?)

Let's say I have a picture of oh...how about a generic landscape - in the daytime. Now let's say I have a picture of the same landscape, but at night-time. Is it possible to somehow make a keystroke combination so I could toggle between the two, without having to keep right-clicking and choosing "set as desktop background..."? This would be quite useful if I had a few different pictures I wanted to constantly switch between. Is this possible, with two, three, or many? Thanks! --Yellow1996 (talk) 02:42, 11 May 2013 (UTC)

On Linux, you could use nitrogen or feh to show a wallpaper, and set up a script with hotkeys to switch them. On Mac, the answer is almost certainly yes--there seem to be plenty of wallpaper managers which could be controlled in the same way. Anything else, and you're on your own. Henry^Flower 15:33, 11 May 2013 (UTC)

Windows 7/8 does it automatically: http://windows.microsoft.com/en-ie/windows7/create-a-desktop-background-slide-show. - Cucumber Mike (talk) 16:09, 11 May 2013 (UTC)

Oh sorry guys, I forgot to mention I'm on Windows Vista. Is it possible on that OS? --Yellow1996 (talk) 19:00, 11 May 2013 (UTC)

If you don't wish to use a program designed specifically for this function, you can set a scheduled task to do it. Follow the instructions in part two of the first answer to this superuser question to create a vbscript to change the wallpaper based on the time. Now open task scheduler, and schedule this task to be run at the appropriate times. You'll also want it to be run shortly after logon to set the wallpaper when you turn on your computer. ⚠Efreak 09:58, 14 May 2013 (UTC)

Looks cool...but is there a way I could modify the code to make the wallpapers change with a keystroke combination rather than on a timer? --Yellow1996 (talk) 23:36, 14 May 2013 (UTC)

slow boot

This is related to the "RetroUI problem" above. I'm using Windows 8. I was using RetroUI, but after the desktop came up, it took about 110 seconds for RetroUI to load. Until then, the mouse cursor did not appear on the desktop.

Now I've removed RetroUI, but I have somewhat the same problem. Now after the desktop does appear, the mouse cursor shows up. However, no apps that I click on will come up. I can click on Computer, explore a drive, click on a batch file on the desktop, and do ctrl-alt-del. But nothing else works for 100-110 seconds after I get to the desktop, when my gadget appears and the rest of the icons appear on the taskbar. Then everything works. (Until this time the only two icons that appear are the "safely remove" and Malwarebytes.)

Any ideas of how to fix this? Bubba73 ^{You talkin' to me?} 04:17, 11 May 2013 (UTC)

It's possible that RetroUI wasn't completely removed from your system. Did you delete all the folders manually, or did you go to uninstall/remove programs? If you did the latter, search around and see if there is anything left over. I don't have experience with that particular software, but this has happened to me many times with other things and is quite a bother. If that doesn't work then I'd do a full computer scan. Good luck! --Yellow1996 (talk) 19:11, 11 May 2013 (UTC)

I did the regular uninstall in the control panel. I'm not sure if this was caused by RetroUI. I do a full virus scan each week and a full malware scan each week, with quick scans each day. I'll try a full scan. Bubba73 ^{You talkin' to me?} 23:31, 11 May 2013 (UTC)

The retroUI folder was still there, but I don't know if that was causing the problem. Anyhow, I deleted it. Bubba73 ^{You talkin' to me?} 23:58, 11 May 2013 (UTC)

In that case, I doubt it's a virus - this was probably all caused by RetroUI. Deleting the folder was a good idea; that could have been the issue. Does the problem persist after you deleted it? --Yellow1996 (talk) 17:37, 12 May 2013 (UTC)

I haven't booted again since I removed the folder. I ran both complete scans last night, but they found nothing. Bubba73 ^{You talkin' to me?} 21:54, 12 May 2013 (UTC)

Well at least we know it wasn't a virus at work there. But next time you're on the system in question see if the problem still exists - and hopefully it doesn't. --Yellow1996 (talk) 01:32, 13 May 2013 (UTC)

I'm back to using Classic Shell. It still takes a long time for the weather gadget and most of the icons to come up, plus a long time before IE will start. Bus some other programs will come up not too long after the desktop is visible - e.g. EditPad, Word, Thunderbird, and Firefox. I had been testing with IE because if the internet is down, it realizes it quicker and handles it more smoothly than Firefox. So maybe it is just taking a long time to boot. (It takes a long time with the dots are spinning too.) Bubba73 ^{You talkin' to me?} 02:24, 13 May 2013 (UTC)

Hmmm... that's quite puzzling. And this all started when you were trying out RetroUI? Switching back to Classic Shell was a good idea but I wonder why it's still so sluggish to boot. Perhaps registry errors? Fragmentation? Junk files? I'm just guessing, but those types of things could be causing you trouble...do you run fixer tools for stuff like that often? --Yellow1996 (talk) 16:21, 13 May 2013 (UTC)

Well, I'm not sure if it all started with the RetroUI trial. But one part certainly did - the mouse used to be usable right after I got to the desktop. With RetroUI, after I saw the desktop, the mouse cursor did not appear until RetroUI loaded, which was 100-110 seconds after the desktop came up. With RetroUI removed, the mouse comes up when the desktop does, but only some things will work when clicked on. For instance, if I click on IE nothing happens until it finishes the entire boot process (the rest of the icons appear in the tray and the weather gadget comes up) - then IE starts. I estimate that the entire boot process takes nearly 10 minutes, and this is a quad-core i7 with a 7200 RPM drive. I clean out junk files from time to time but I don't do registry cleanup anymore because I read that they really don't help much. Bubba73 ^{You talkin' to me?} 16:33, 13 May 2013 (UTC)

Okay, that definitely should not be happening on an i7. So if there already were problems before, they could have just gotten worse coincidentally when you were trying out RetroUI - while that software itself only caused your mouse troubles - therefore misleading us as to what the real problem is. If this is really annoying you/hindering stuff you are doing on the computer I would just take it in to a specialist to see if they can figure it out...though that can be expensive! --Yellow1996 (talk) 16:44, 13 May 2013 (UTC)

This computer came with Windows 7, upgraded to Windows 8. I didn't time it, but W8 seemed to boot faster than W7 - used to at least. I just rebooted and timed it (min:sec - elapsed time from restart).

0:00 restarting

0:45 blank screen

0:55 blue window logo, spinning dots

3:35 blue welcome screen, sound

3:50 desktop appears

6:25 completely finished booting

I didn't touch it in the process. Bubba73 ^{You talkin' to me?} 16:50, 13 May 2013 (UTC)

Wow. So the slowdown is definitely on the desktop! So does the computer have the same speed as before while you are doing things like browsing the internet and running programs (is the slowdown only in the booting process)? --Yellow1996 (talk) 16:57, 13 May 2013 (UTC)

I had something similar on a PC running XP. When I got it, it would be workable quickly. Subsequently it spent a long time on the "Loading Windows" or somesuch. I eventually traced it to having turned off bluetooth. It was obviously timing out trying to find it. Turn it back on and all was well. Could it be something similar? --Phil Holmes (talk) 17:03, 13 May 2013 (UTC)

Generally, after it finishes booting it seems OK. There are two little things compared to the way it was a couple of months ago: (1) every few minutes there are burps when playing back a sound file - itunes or YouTube, (2) every once in a while (maybe a few times per day), while typing, the letters I'm typing don't appear right away, but after a few seconds they suddenly appear. Bubba73 ^{You talkin' to me?} 17:09, 13 May 2013 (UTC)

Hmmm...your second thing happens to me sometimes as well; though that's to be expected from a 5-year-old laptop running Vista. I'd say my above advice to take it in if this is an urgent problem for you is what I'll stay on. --Yellow1996 (talk) 17:15, 13 May 2013 (UTC)

Have you checked what is running at start-up? I believe they moved the interface for that into the task manager, or you can probably find it by searching for startup. I would also check through the device manager and see if there is anything unusual - I don't know how RetroUI does its magic, but it is plausible that there could be a driver running in the background to help it out, and maybe it didn't uninstall properly, although I suspect that it would cause problems earlier in startup. You could also check the list of running services and see if any are related to RetroUI or other third-party software you have installed. 38.111.64.107 (talk) 11:45, 14 May 2013 (UTC)

I have several things starting up, but the Task Manager doesn't show anything for RetroUI - either running or in the startup list. Bubba73 ^{You talkin' to me?} 00:43, 17 May 2013 (UTC)

You can try searching your registry for any references to RetroUI. If nothing else works, you can refresh your PC: Windows 8 Tip: Reset or Refresh Your PC. A Quest For Knowledge (talk) 18:15, 17 May 2013 (UTC)

PHP geolocation consent on smartphones

In the hypothetical scenario where a friend's phone was stolen, would it be possible to send to that phone (via SMS or Whatsapp) a link to a webpage that geolocates the client, and if the thief clicked the link, the page could locate the phone without any other consent? Or would they get a popup saying something like "Do you want to share your location with [webpage]?" --Markr4 (talk) 09:32, 11 May 2013 (UTC)

It’s been a while since I looked into it, but IIRC you can do a number of things if GPS was left on or if you had preinstalled an application designed to deal with this type of situation. If your friend’s phone was stolen and it has any personal information on it and no locking mechanism (screen lock, password, etc.) whatsoever, the first thing you should do is call your provider and have them brick it. No phone is worth criminals having access to the kinds of information stored on them. ¦ Reisio (talk) 10:28, 11 May 2013 (UTC)

I don't really understand the suggestion here. In most places and countries, the most your provider can do if you report your phone as stolen is add the IMEI to a black list. (In some countries like the US, it's commonly said that the phone is bricked, but this seems unnecessary confusing in the context, even more so with smart phones where there's a lot you can do with the phone even if it no longer works with mobile networks.) In a number of countries these black lists are shared with all local providers. There have even been some attempts to develop shared international black lists, although I'm not sure how far these have got. Either way though, these stop criminals using the specific phone on mobile networks which is intended to discourage theft (although there's still the problem of people changing the IMEI), but don't achieve much else.

In particular they will not generally protect your personal information. If the information is stored on the phone, the fact that the phone is blacklisted is of no consequence since the information is still stored on the phone. A smart thief intent on stealing the info would likely disconnect the phone from all networks from the moment they can do so (to prevent tracking and also to reduce the possibility of an app activated remotely doing stuff) and then use forensic tools to backup all data from the phone and analyse it from there so the IMEI being black list is of no consequence, they won't even know it happened. A dumber thief may use the phone until it now longer works, and then try to recover the data, if they're careless they may have already killed some of it, but most of it will still be there.

For information stored remotely (i.e. in the cloud) but for which the password or some access code is stored, it's more complicated, but the phone being blacklist would not generally help much unless the service is intrinsically tied to the device which isn't very common. For such information, the more important thing to do would be to change the passwords for all these services. This would generally get round the problem of compromised passwords, and many services also kill all cookies and similar tokens when you change your password (unfortunately not all).

I'm not saying you shouldn't report your phone as stolen, a more important reason is not to blacklist the phone stolen, but ensure the mobile provider deregister or block the specific SIM card or connection between the phone and your mobile account. (I think you could normally tell the provider whether you want the IMEI blacklisted or not, so you're not forced to do both at the same time, but I'm not sure.) This stops them using services you may have to pay for and more importantly stops them spoofing you which can be important nowadays with the way some services including banks sending passwords or tokens to mobile phones. (It would also stop them trying to scam or just plain annoy your friends and relatives.)

Note however this could also be counter productive if you do have a lot of valuable information stored on the phone. As mentioned below, iPhone has a phone locator service. The Google Play store on Android phones generally allows remote authentication for the installation of apps (you choose to install the app on a browser while logged on and when the phone has network access it will download and install the app), so you can install either a locator app or a data deletion app. As most criminals don't really know what they're doing, quite a few will give the phone mobile network access (if you haven't disabled it, just turning on your phone or leaving it on will usually be enough if they don't do anything) enabling you to run these apps to either delete data (in the case of Android) or locate the phone and attempt recovery. Having it black listed will not generally stop it being used with wifi, but it may discourage the thief from using it.

Ultimately you'll have to make the choice between different factors at play. It may be that your network would be willing to partially block a phone or limit the ability of the thief to use services to ensure they don't spend too much money. In addition, you could disassociate the phone number from anyone services which may send passwords or tokens to it (in some cases this may result in a SMS notification being sent to your phone, but perhaps you can stop that if you report the reason is because of theft).

Nil Einne (talk) 03:34, 12 May 2013 (UTC)

For the iPhone there's Find My iPhone, which can also remotely lock the device. AndrewWTaylor (talk) 13:26, 11 May 2013 (UTC)

Whether a web page can see your location without asking permission is up to the browser. You could visit the web page beforehand and permanently approve it to see your location, but your scheme still requires a pretty dumb thief to work. I have no idea what percentage of thieves are that dumb.

There are apps that will autoreply with the phone's location to an SMS message containing a preset phrase, such as this one for Android. -- BenRG 07:22, 12 May 2013 (UTC)

GMAIL SETTINGS

I use Gmail.

1. How can I set the emails from unknown sources, received in the spam folder instead of inbox folder?
2. How can I block bogus/unwanted emails, not even received in the spam folder at all?
3. Even thought I requested, I don’t receive email updates from some blogs/web pages. How can I receive those email updates?

Please help me to solve the above problems. It may be due to that I am not familiar with the technical terms. Thank you.175.157.181.240 (talk) 10:22, 11 May 2013 (UTC)

Gmail has some kind of an automatic spam filter, although you can filter specific emails to automatically go to spam based on the sender. Some websites like Wikipedia itself have an option to turn on emails, but it varies by blog/website. Numbermaniac - T- C 10:26, 11 May 2013 (UTC)

May 13

E top-up and e-vouchers in the UK

How are E top-up cards and e-vouchers used in the United Kingdom for topping up mobile phone SIM card accounts?

I was not sure whether to ask this here or at the humanities reference desk (as it concerns finance), please move as necessary.

While looking for a Pay as You Go SIM card for use both in the UK and while roaming, I noticed the methods of topping up were quite limited (I am used to European SIM cards where I can top up at any TABAC or online with any credit card). Also, I had hoped that wikipedia would have had an article on the term E Top -up which is quite new to me. The related term e-voucher is also a redlink - the section in ORCA card appears specific to Washington State, USA.

Some websites partly explain the concept: [1], and [2]; but I was looking for how an E Top-up card is obtained and used by the end-user, and more background on the term and possible synonyms (for example "TopUp swipe card" from Vodafone sites). Ideally I would like to see a video of someone obtaining and using such a card with an ordnary non-smart mobile phone, or online in a browser.

I don't know the specifics of the system in the UK, but AFAIK in most places where such systems are used, they basically involve the person paying money (cash or possibly debit or even credit cards depending on what the norm in the local country and other factors) to whatever store offers the topup/reload vouchers, the store then entering the amount and the machine (in some cases it may be tied to the cashier machine) then prints the voucher with a unique number. The person can then either call a generally free number on their phone, follow the prompts (e.g. push 1 to topup, push 1 if you are using a topup voucher, enter the number and then press the hash key) and when down the system will likely tell them if their topup was successful, how much the topup was and what their current balance is (You successfully topped up your account with 20 dollars/pounds/whatever. You new balance is 44.96 dollars/pounds/whatever.) Alternative they can sent the topup number to a special SMS number and they will receive a reply telling them something similar to the voice service. I'm not sure that many bother with using online services for such vouchers but if they are possible, they would like involve logging on to your account and then selecting the topup with voucher option and entering the number. I'm not sure if it's common that you can topup other numbers with such vouchers although it may be possible if the voucher topup works exactly the same as with credit card etc. I think in most countries, normally people will just send the number by SMS if they want to gift someone a topup with a voucher, or give it in person.

In some cases you may also be able to buy the vouchers from vending machines, but particularly if vending machines accept credit or debit cards or something else which requires a network connection they may just ask you to enter the mobile number and then they tell the service to topup your number so you don't receive anything other than perhaps a receipt and an SMS when the topup has succeeded. Similar to the way ATM topups usually work AFAIK (although commonly you may also be able to tie a number to your ATM).

I'm not sure whether evoucher systems need a network connection. I originally thought they did since they got the unique topup number from the provider but on further consideration I think I'm mistaken, likely the machines can generate the number themselves and use a unique seed so the provider knows who it's from. (There will be some complexity in balancing the accounts since the machine and retailer will count the moment the voucher is produced, the provider only knows when it's used.) If they do and the machine only accepts cash, then perhaps it will have traditional topup vouchers so no network connection is needed but otherwise evoucher is a lot simpler since they only need electricity and someone to collect the cash every so often rather then also reloading the cards. It could of course be that both are in play depending on the country and provider or the machine can generate the numbers but does need regular reconciliation with the provider to reduce confusion from purchased but unused vouchers.

The top-up swipe card you refer to in the UK appears to be different from a voucher, from the description on the Vodafone site it sounds like you have a swipe card linked to your account which the retailer swipes to send the topup directly to your account so there's no voucher involved. Such a system definitely requires a network connection.

BTW, I'm pretty sure the evoucher is just a slightly modified version of the older system probably common in most countries (including Europe) where prepaid services were common using cards (vouchers) generally of the 'scratch and win' type (to ensure the card hasn't already been used before purchase) which is probably still somewhat common in some countries.

The advantage of the electronic system is you remove the need to keep any stock on hand of cards and all the problems associated thereof of needing to store, restock and manage stock levels to ensure you don't have too many or too few or they are lost or stolen, you may also be able to offer more values although I think many systems still only allow a small range of values for evouchers (i.e. you can't topup $24.53 and probably not even 24), however the range could be larger. From the providers POV, they don't have to produce the reload cards using reasonably high security systems (i.e. costly). Also for big retailers, they may let them tie it in to their checkout system so there's no need for separate machines or receipts. It also likely makes some degree of tracking easier since someone (as per my earlier comments on the network connection, it could be the provider, more likely the retailer or the machine) may keep records of precisely when the topup was purchased and the provider may keep records of what number if was used to reload. (And if they do use a unique seed, the provider can then ask or tell interested parties the retailer who has that seed for their records.) Besides the obvious and perhaps controversial use when the police are trying to track a mobile phone or tie it to a person, it would likely be useful in the even of disputes.

The main disadvantage compared to traditional cards is the cost of the machines (including maintenance etc) to generate the vouchers which someone has to pay (if the retailer integrates it in to their system then there's the cost of the integration). The machines at a minimum will also need electricity and likely the occasional refill of thermal paper. The machine will also likely take up more room in an accessible location (depending on the number on hand, the stock of cards may take up more room overall but these can be mostly stored elsewhere). And while you could print the vouchers and take them around, this would require a greater degree if trust compared to unscratched cards. Presuming they don't need a network connection or regular reconciliation with the provider, I suspect that vouchers from machines also have shorted expiry dates then cards (which could potentially never expire) to reduce the confusion from purchased and unused vouchers (particularly in the case of theft or alleged theft of the machine). And of course under either scenario, you may have to pay for the voucher the moment you print it out whereas I'm not so sure with cards and either way the retailer could likely return them unscratched and effectively not pay.

Either way, such vouchers do add cost but the overall advantage is that there's no need for credit cards or ATM cards or online banking or debit authorisation which not everyone may have or trust (in developing countries or 15 years ago even less so) which are usually required for alternative systems. And debit authorisation without online banking or similar is a complexity people may not want to deal with.

Note that if a network connection is available, instead of vouchers they could use a system whereby you enter your phone number similar to the way you do with ATMs and possibly some vending machines, that adds time while the checkout operator is waiting (even more so if the machine asks for it twice to reduce the possibility of errors) and considering some people don't know their number off hand and people may also be reluctant to enter their numbers if the retailer can see it. (The system used by Vodafone in the UK with swipe cards eliminates both problems.) It may be in some countries (and this would also apply to vending machines) that the voucher is familiar enough that most people prefer it even if there's no reason they couldn't just use an enter your number system. One obvious advantage of the voucher system is you can keep the number and not use it but have it on hand if it's ever needed (probably stored in your phone, particularly if it was printed on thermal paper), e.g. as a way of controlling usage. It also allows a simple networking based method of almost instant topups and credit where if a friend or someone who trusts you sells such vouchers you can SMS them and they can send you a voucher in reply and you can settle the transaction later. (They could also use send the topup directly to your phone but that would require them to have a network connection and even if they have a smart phone I don't think all providers make their commercial topup sites free. While they have to have the vouchers stored in their phone, once that's done there's a fair chance it'll also be faster to just send you a voucher then enter your number in to a topup site.)

One interesting point is that in some countries where provider enforcement of exact pricing is limited, you can sometimes purchase such vouchers (whether the cards or the evouchers) for slightly less than the face/topup value from certain retailers or perhaps from forums or other places. Although the amount saved is small since they don't actually earn much per transaction. (This can also happen with topup your phone directly systems, particularly if they allow value transfer cheaply and there's significant advantages to big topups.)

Nil Einne (talk) 04:27, 13 May 2013 (UTC)

Pioneer DDJ Ergo?

What's the difference between DDJ Ergo-V & DDJ Ergo-K? Which is better? 220.233.20.37 (talk) 08:47, 13 May 2013 (UTC)

The Ergo-V is given a 4.5/5 here but a 3.5/5 here. The Ergo-K has an average rating of 4/5 (based on 19 ratings) here. As for which is better, you should read through those pages and make the decision for yourself; as you probably know exactly what you want to get out of it. --Yellow1996 (talk) 16:31, 13 May 2013 (UTC)

GIF images/IE9 Favorites

This time, I've got two questions: 1) Why do some GIFs load in your default Internet browser rather than the usual picture-viewing interface? Is there a way to change this? 2) Is it possible - in IE9 - to check and see when you added a certain webpage to your favorites? Thanks! --Yellow1996 (talk) 16:15, 13 May 2013 (UTC)

Files do not load themselves; a user interacts with a user interface, causing the operating system to either directly or indirectly launch a computer program that loads the file. You may find our article on file association helpful. If you are using Windows, you may adjust settings using the default programs control-panel interface. Nimur (talk) 17:27, 13 May 2013 (UTC)

I tried to right-click and open the GIF file in Windows Live Photo Gallery (what I usually use) but it says that "Photo Gallery can't open this photo or video. The file may be unsupported, damaged or corrupted." - I'm fine viewing them in IE, it was just a curiosity question; but thank you anyway! :) also, does anyone know if my second scenario is possible? --Yellow1996 (talk) 17:36, 13 May 2013 (UTC)

If you're using Windows 7, this may help you. -- 140.202.10.130 (talk) 20:28, 13 May 2013 (UTC)

I'm actually on Vista - sorry (I really need to start specifying this.) But thank you for finding that info for me anyway. Like I said before, it's no big deal; I can view them in IE no problem. :) --Yellow1996 (talk) 01:24, 14 May 2013 (UTC)

Could it be that the ones loading in the browser are animated GIFs, which the regular picture viewer doesn't support ? (They might not appear animated, if they just repeat the same frame or if your browser is set to not show animation automatically.) StuRat (talk) 19:33, 14 May 2013 (UTC)

Yes!!! They do appear animated, so that's definitely the answer to this mystery. Thanks, StuRat! :) --Yellow1996 (talk) 23:39, 14 May 2013 (UTC)

You're quite welcome. StuRat (talk) 00:32, 18 May 2013 (UTC)

pascal programming "menu" question

I was assigned to write a program that resembles a "menu" in that there are a set of rectangles that change color when using arrow keys. There are two problems with my program and I can't figure out why:

1. even though I used the "readkey" line twice (by writing "ch:= readkey; if ord(ch)=0 {or keypressed} then ch:= readkey" I still have to press arrow keys twice to make it work.

2. When going from the first item of the "menu" to the last one by pressing the "↑" key, the first item remains colored although there's a "cleardevice" command at the beginning of the loop.

here's the (main part of the) program

initgraph(gd,gm,);
setbkcolor(0);
setcolor(10);
rectangle(200,100,400,400);
readln(n);
d:=300 div n;
for i:=0 to n-1 do rectangle(200,100+d*i,400,100+(i+1)*d);
y:=100+(d div 2);
floodfil(300,y,10);
Repeat
Begin
ch:=readkey;
if ord(ch)=0 then ch:=readkey;
cleardevice;
for i:=0 to n-1 do rectangle(200,100+d*i,400,100+(i+1)*d);
If ord(ch)=72 then if y-(d div2)>100 then y:=y-(d div 2) else y:=100+n*d-(d div 2);
If ord(ch)=80 then if y+(d div2)<400 then y:=y+(d div 2) else y:=100+(d div 2);
setcolor(10);
floodfill(300,y,10);
delay(60);
End;
until ord(ch)=27;
readln;
closegraph;

--Irrational number (talk) 21:58, 13 May 2013 (UTC)

I've added source-code formatting to your code for improved readability. Nimur (talk) 22:05, 13 May 2013 (UTC)

For #1 - it looks right to me (It has been long time since I've done this). For function keys and arrow keys, etc, ReadKey first returns a 0, then the next call returns a code to indicate the key: 72 for up arrow, 75 for left arrow, 77 for right arrow, and 80 for down arrow. (The 27 is for esc.) So it looks basically right to me, based on my memory. Trace through the program to see what is happening. Bubba73 ^{You talkin' to me?} 23:03, 13 May 2013 (UTC)

PS - I would keep track of a line number, have a routine to translate the line number into the coordinates, and have the arrow keys change the line number and then update the screen coordinates. Bubba73 ^{You talkin' to me?} 23:07, 13 May 2013 (UTC)

And you don't need the begin/end inside the repeat/until. Bubba73 ^{You talkin' to me?} 01:40, 14 May 2013 (UTC)

I have a couple of other thoughts. (1) is ch an 8-bit character or could it be a 16-bit unicode character? If it is 16-bit, that could be the problem. (2) I'd test reading the arrow:

ch := readkey;
if ch = chr( 0) then
begin
  ch := readkey;

  case ord( ch) of 
    75 : writeln( 'left arrow');
    77 : writeln( 'right arrow');
    else writeln( 'other'); 
  end;
end;

Bubba73 ^{You talkin' to me?} 04:06, 14 May 2013 (UTC)

I did test it that way and it works right. But I still can't figure out what's wrong with the program. Maybe there's something wrong with my version of Pascal. There are other problems too. like when I floodfill the rectangle it fills it with white color even though I never used white in this program. Can anyone run the program in pascal, see if it works?--Irrational number (talk) 10:19, 14 May 2013 (UTC)

You haven't posted the whole program, told us which version of Pascal (it's not very standardised), or what OS. I'd personally recommend you post code at pastebin. -- Finlay McWalterჷTalk 10:24, 14 May 2013 (UTC)

There isn't really much else, just the variables and "gd:=detect" to use graph.--Irrational number (talk) 11:22, 14 May 2013 (UTC)

For what it's worth, here is part of some ancient code I managed to find in my archives. It might not make any sense but hopefully it will show you how we handled keys back in the DOS days. Why not just use Delphi now? Sandman30s (talk) 14:46, 14 May 2013 (UTC)

repeat
  key := readkey;
until (upcase(key) in [#0, #8, #13, #27, 'A'..'Z', '*']);
if key = #27 then 
  begin nm := ; exit; end;
if ord(key)=0 then
begin
 key := readkey;
 case ord(key) of
   75 : begin                                 {left}
          pos := pos-1;
          if pos=0 then
            pos := length(nm);
          if nm= then pos := 1;
        end;
   77 : begin                                 {right}
          pos := pos+1;
          if (pos=41) or (pos=length(nm)+2) then
            pos := 1;
          if nm= then pos := 1;
        end;
   83 : begin                                   {del}
          pos := 1; nm := ;
          writeout;
        end;
 end;
end;
if (ord(key)=71) or (ord(key)=73) then       {Hm, PgUp}
  pos := 1;
if (ord(key)=79) or (ord(key)=81) then       {End, PgDn}
  pos := length(nm);

May 14

Convertion of MNEMONICS

How to convert mnemonics into machine code ?117.204.231.251 (talk) 07:49, 14 May 2013 (UTC)

This is usually done by a program called an assembler - see assembly language. Gandalf61 (talk) 08:18, 14 May 2013 (UTC)

Laptop will not boot

I have a problem with my laptop. It stoped running. The power led is on but the machine doesn´t boot. Some says is the CPU and some says is the South Chipset. What do you say, guys??  Miss Bono (zootalk) 17:05, 14 May 2013 (UTC)

I moved your question to a new section. You have not provided nearly enough information for us to begin helping you. A good place to start would be to list the make, model, and year of the computer. Realistically, if the symptom is a total failure to boot, we probably will not be able to gather enough information to troubleshoot this problem via conversation over Wikipedia; nor is the computer reference desk the best place to provide technical support for such issues. You might consider calling the vendor or seeking out a third-party repair shop. Nimur (talk) 17:55, 14 May 2013 (UTC)

I will give you the model and the year, anyway. It is a Toshiba Satellite M300 Series year 2008.  Miss Bono (zootalk) 18:00, 14 May 2013 (UTC)

Perhaps a little more info will let someone speculate whether Miss Bono should be looking for a repairer or whole new laptop. So what happens when you press the power button? Anything on the screen - white letter on a black background, inviting you to press a key to enter "setup", for example? Any noises, like a distinct pattern of beeps? or perhaps clicks or rough grinding noises from inside the laptop? Astronaut (talk) 19:28, 14 May 2013 (UTC)

Do they still use beep codes on power up? I think a single short beep is normal and other patterns of beeps can point to the problem. Have you tried putting a 'system' disc in the drive? A windows install disc or similar may boot to a safe or install mode.--Canoe1967 (talk) 19:35, 14 May 2013 (UTC)

When I press the power button it (the boutton) just light on but the computer does nothing.  Miss Bono (zootalk) 19:40, 14 May 2013 (UTC)

It could be the button itself, a fuse, or power supply circuit. I think even when major failures in the circuits happen you should still get beeps. For a 5 year old computer it may cost more to have a pro even look at it then the cost of a used one 2-3 years old. If you want stuff from the hard drive it may be still intact. If you aren't getting to the beep phase the failure is probably before the hard drive boots up.--Canoe1967 (talk) 20:24, 14 May 2013 (UTC)

According to my computer science knowledges (not much but not few) and according to some Computer Scientists, it might be the CPU or the South Chipset (Video Chipset). It has no beeps, or signal of working. The HDD is good, I tested in a SATA Hard Drive Enclosoure in another PC and it works. My laptop was overheating to 95º C... Miss Bono (zootalk) 20:30, 14 May 2013 (UTC)

Typically, the cost (in time and money) needed to diagnose and repair a problem on the main logic board of a consumer laptop is much higher than the cost to totally replace the entire computer system. Nimur (talk) 20:33, 14 May 2013 (UTC)

There is nothing you can do except take it to a repair shop (or get a new laptop). Looie496 (talk) 21:17, 14 May 2013 (UTC)

I found a video on how to take it apart. http://www.youtube.com/watch?v=Vgtii0U9a0s He has other videos as well. If it was overheating then the thermal switch may be stuck? I don't know where that would be though. He does mention that you can contact him.--Canoe1967 (talk) 21:17, 14 May 2013 (UTC)

Thank you guys!! :) Miss Bono (zootalk) 12:14, 15 May 2013 (UTC)

May 15

Software for scanner

I'm looking for scanning software. The software that came with my HP scanner will not save any settings (at least not the ones that matter). I use the scanner to make PDFs, to scan photos and documents to files, and to act as a photocopier. What can fit that bill? Bubba73 ^{You talkin' to me?} 04:25, 15 May 2013 (UTC)

software to crop PDFs

I'm looking for software to crop PDFs that are scanned in. The ones I make from my scanner have a lot of stuff around the edges that are outside the original document - I'd like to eliminate that. (Some scans are of multiple pages.) Bubba73 ^{You talkin' to me?} 04:28, 15 May 2013 (UTC)

I use BRISS - GNU GPL http://sourceforge.net/projects/briss/ It's not as intuitive as claimed but really easy once you understand the process. The software merges/overlays all the pages in the document allowing you create a single crop area to be applied to all the pages. This is not useful to me so I need to tell the software to exclude page 2 to the end of the document from the merge. You can then specify a crop rectangle for each page. At about 9megs, free and no install required I love it. 196.214.78.114 (talk) 10:29, 15 May 2013 (UTC)

Resolved

I tried it on a one-page PDF and it worked pretty well, although the cropped file was the same size. But size isn't important - except when I did it in photoshop, the resulting file was more than 10 times as big. Bubba73 ^{You talkin' to me?} 16:59, 15 May 2013 (UTC)

Break havoc in Linux without admin password

I understand that you cannot install programs without being admin, but isn't it a little bit insecure to be able to run scripts like rm whatever, or others, without any password? OsmanRF34 (talk) 13:22, 15 May 2013 (UTC)

You should not be able to remove a file for which you do not have write-permission. File permissions should be set correctly and managed by an administrator as part of a complete security policy. Nimur (talk) 13:40, 15 May 2013 (UTC)

You can only remove files from folders to which you have write permission. In practice, for an ordinary user on a normal config, that mostly means you can only remove stuff from your own home, and stuff you created in /tmp. It's also not entirely true that one has to have superuser permissions to install programs, because it's quite possible to install a program for a single user - in which case stuff only goes into that users' home. Unfortunately many programs' idea of being installed does envisage their config files being in /etc, so this isn't as true as it could be. -- Finlay McWalterჷTalk 13:41, 15 May 2013 (UTC)

md5sum of installed program in Linux

I know that when you download a program you do an md5sum check on the installation file, but can you do the same on already installed files, to check if they were not tampered with? OsmanRF34 (talk) 13:24, 15 May 2013 (UTC)

GNU coreutils (which is installed on just about every Linux system) includes a command line md5sum binary, so one can obtain the md5sum of any given file. One can verify that against what its source says it should be, if the source publishes that info somewhere. -- Finlay McWalterჷTalk 13:44, 15 May 2013 (UTC)

You can compute the checksum for any file on which you have read permissions. If this is part of a tamper-evidence security policy, there are other concerns: a mismatching md5 sum might not indicate malicious tampering. The whitelist of approved checksums might be large and must be secured. The integrity of your md5 program must be secured. These problems are part of the field of trusted computing., and application whitelisting and file integrity verification are common strategies applied as part of a total security solution. Nimur (talk) 13:45, 15 May 2013 (UTC)

"rpm -q --verify PACKAGENAME" does exactly that. --Sean 16:59, 15 May 2013 (UTC)

On Debian (apt) systems like Mint, Crunchbang, Knoppix, and Ubuntu, one uses debsums PACKAGENAME for this. -- Finlay McWalterჷTalk 09:58, 16 May 2013 (UTC)

Learning Data digitization

HI all, can anyone please help suggest me a website or any resource to help me learn Data Digitization ,any info or help would mean a lot as i tried searching online but was to no avail,.thanking you all in advance.regards jane — Preceding unsigned comment added by 117.199.64.5 (talk) 14:37, 15 May 2013 (UTC)

the reason your search does not succeed is that the term doesn't really mean anything definite. Are you trying to learn about analog-to-digital converters? Looie496 (talk) 16:36, 15 May 2013 (UTC)

The OP may be referring to digitization of data as in the digitization of documents etc. --Yellow1996 (talk) 01:41, 16 May 2013 (UTC)

3D maps

If I have a map of a particular area, with contour lines showing different heights, or shaded so each colour represents a different height, is there any way of converting that into a 3D model just by feeding the data into a computer program, rather than having to go to the trouble of sculpting every individual point on the surface? 213.104.128.16 (talk) 16:16, 15 May 2013 (UTC)

See "3D printing".—Wavelength (talk) 16:31, 15 May 2013 (UTC)

If your map is in the form of an image that shows labeled contour lines, then this is quite a difficult problem, and I don't think you'll find a general-purpose solution. If the color code can easily be decoded, then that's a much simpler situation, but it would still be necessary to write a special-purpose program to do the job. Looie496 (talk) 16:39, 15 May 2013 (UTC)

There may be a Hackerspace in your area with a 3D printer. They may be able to help convert it to a printing format as well. http://hackerspaces.org/wiki/List_of_Hacker_Spaces has a large list.--Canoe1967 (talk) 17:46, 15 May 2013 (UTC)

OP, do you want a physical, concrete model? All the responders so far seem to think so, but let us know if you just want a 3D software model. In either case, some data extraction program (such as data thief [3] would probably help convert your contour lines to a XYZ mesh. SemanticMantis (talk) 18:05, 15 May 2013 (UTC)

Inkscape can also vectorize raster-images using the Inkscape Potrace feature. Once your contours are vectorized, you can proceed to migrate them to a more convenient 3D modeling format; and if you actually do intend to print or cut a physical version of the model, you can convert to an appropriate input format for your printer or cutter tool. Nimur (talk) 18:26, 15 May 2013 (UTC)

If you mean a "software" model, then I think what you are after could be fairly easily acheived using a Heightmap, the article has links to software you can use. Vespine (talk) 23:02, 15 May 2013 (UTC)

Yea, I did mean a 3D computer model of the map, I have a 3D printer that could then print that out easily, though it would be too small to be much use for anything, I think. What I have so far is a map where each layer is a different colour for a specific height. Though, I'm thinking, that would make it go up in steps rather than smoothly, once I have a program that can turn it into a 3D form, would it be possible to set it so a certain edge of each space is that specific height, and then slope down from there? 213.104.128.16 (talk) 23:03, 15 May 2013 (UTC)

If you want something bigger than a 3D printer you can move a small drill using a screw driven by a stepper motor for the z in a big xy plotter arrangement and shape the profile out of polystyrene. It is easy enough to program the intermediate heights to be a reasonable but usually I'd have though you'd have started with the measured heights of various points in the area. Dmcq (talk) 00:09, 16 May 2013 (UTC)

Did you look at the heightmap article? I played around with height maps using the farcry level editor (a computer game). If you can make your image grey scale with white value representing height, you can even use photoshop tools to edit the image however you like. For example, if you have distinct steps but want a smooth gradient, you can simply use the blur tool on the lines until they are a smooth gradient, or you can even try the gradient tool if you work out how to use masks and stuff. It will take a bit of playing around depending your photoshop skills and how nice you want to get the result, but it's definitely not the most impractical way of doing it. Vespine (talk) 04:12, 16 May 2013 (UTC)

There's various interpolation techniques but if you want to do something simple yourself scan in a map. Set up a binary array of where the contour colour changes. Go across all the lines of the image linearly interpolating between successive points like that. Then get the average with doing the same in the columns then finally do a few sweeps of averaging the four closest points with a point except where the original binary array is set. That should get you a pretty good linear smoothed version just by scanning in a map. Dmcq (talk) 11:29, 16 May 2013 (UTC)

I was thinking more setting it to interpret certain edges of pixels rather than their whole width as a set height. Thing is, it's already a 60 megapixel image, in which some height differences are a single pixel wide as it is, extending that to a sufficient resolution and then interpolating between every single line of that seems like a huge job. 213.104.128.16 (talk) 14:59, 16 May 2013 (UTC)

Well I think I'd use something faster than Visual Basic for that ;-) But computers are quite fast enough and big enough to crunch through all that with the way I said. Dmcq (talk) 11:31, 17 May 2013 (UTC)

May 16

Password Protecting an External Hard Drive

I have a Seagate 1TB external hard drive. Is it possible to password-lock it; so for instance when I plug it in it says "Please enter the password to gain access." - or something like that? Thanks! --Yellow1996 (talk) 23:40, 16 May 2013 (UTC)

TrueCrypt is one option. ¦ Reisio (talk) 23:50, 16 May 2013 (UTC)

Some drives have firm-ware locking, as you describe, but the much better, and more compatable option is to use full disc encryption, such as Truecrypt, as Reisio advises. Shadowjams (talk) 05:51, 17 May 2013 (UTC)

May 17

Sharing of files in Nokia Lumia

Is it possible that Nokia Lumia could automatically share files from the phone (e.g. pictures and notes) to the contacts? Or can applications like Skype or Whatsapp do that? I don't want this kind of function, I'm thinking about privacy. — Preceding unsigned comment added by 85.76.122.80 (talk) 06:48, 17 May 2013 (UTC)

Apache Tomcat newbie needs help.

I'm a web developer who deals primarily with Microsoft technologies. At my job, we need to make a change to one of our web apps which is using Apache Tomcat. Unfortunately, nobody here knows anything Apache or JSP. (The Apache Tomcat server was set up years ago and who ever did it, has long since left the company.) What we want to change is actually pretty simple and would have taken me a couple minutes to do if this was ASP.NET/IIS.

Currently, if there's an unhandled exception, Apache Tomcat displays an error message that looks like this.[4] We do not want to display the stack trace to the user. (This is considered a security vulnerability to one of our clients.)

I found the following article which explains how to do it:

How to show user-friendly error page instead of tomcat log with stack trace in browser when runtime exception is thrown?

However, when we tried it, this seemed to have no effect. There's about 20 different web.xml files on the server, so we're not sure we even modified the correct one.

So, anyway, I guess I have two questions:

1. How do we determine which of the 20 web.xml files is the one we need to modify? One idea I have is to put to replace contents of the web.xml file with garbage and hope that Apache Tomcat throws an error saying it can't parse the web.xml file. We could use process of elimination until we find the one we want. Does anyone know if Apache Tomcat will throw an error if it encounters a bad web.xml file or will it simply ignore the web.xml file?
2. Do we have to restart Apache Tomcat to see a change in the web.xml file?

We're user Apache Tomcat 5.0.27. Any help would be greatly appreciated. AnonComputerGuy (talk) 13:59, 17 May 2013 (UTC)