Wikipedia:Reference desk/Archives/Computing/2010 January 28

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January 28

PHP Login recommendation please?

Can someone in the know please recommend a good PHP login script for me? I don't want to roll my own because I'm still only getting my feet wet in PHP and am not confident I could produce a secure system. The Catch-22, though, is that I'm also hesitant to pick out a script from the wild because I'm not sure I'd be able to accurately appraise its security & quality... because I'm still only getting my feet wet in PHP. :-) Ideally, the script would allow for multiple levels of user privileges (basic/contributor/admin for example) and would have email confirmation/password reset ability. Failing that, I can always bolt on my own scripts for those features in the end. Thank you for any assistance you can provide! 218.25.32.210 (talk) 00:50, 28 January 2010 (UTC)

What backend do you want to use? PHP doesn't store any data. Are you going to store it in text files? Are you going to store it in MySQL? Are you going to store it in Excel spreadsheets? Do you have an LDAP server? Without knowing what you plan to do, it is hard to tell you what to do. In the end, a login script is rather straightforward. The common method is to store the user's password as a salted hash in a database. When the user logs in, you salt and hash the password they supply. If it matches what is in the database, you let them in. Use $_SESSION to store that they are logged in - as opposed to sending the password back and forth repeatedly. Anything extra is straighforward as well. Levels of security are nothing more than flags for the user in the database. A password reset will just change the hash and email a temp password to the user. -- kainaw™ 02:11, 28 January 2010 (UTC)

MySQL. 218.25.32.210 (talk) 02:33, 28 January 2010 (UTC)

Kainaw, a very simple log-in script is easy, but something that is a bit more bullet-proof, and has more features (like being able to reset the password securely), is a non-trivial endeavor, even for an experienced programmer. This is not what I would consider a "do it yourself" job unless you really didn't care if it was secure or not. --Mr.98 (talk) 22:07, 28 January 2010 (UTC)

Resetting a password is not complicated. Create a reset key. Email that to the user. User goes to reset page with reset key. If it is valid, allow the user to enter a new password. Done. Afraid people will automate the sending of reset keys just to be a pain? Add a captcha to the "I forgot my password" page and the reset page. Now they have to be humans. I do not see such a small algorithm to be complicated. -- kainaw™ 14:19, 29 January 2010 (UTC)

USB drive shrunk....

My USB drive is supposed to be 4GB... now it's only 385MB with 3.37GB of unallocated space for some reason! Windows won't let me add, delete, expand, or shrink any partitions on it either!! Why?? --76.221.146.179 (talk) 03:39, 28 January 2010 (UTC)

I've run into similar situations in the past. I think it had something to do with me deleting things off of it in Linux, and Windows not recognizing it correctly. I can't remember for sure, but whatever the case was it made absolutely no sense to me. In retrospect, Linux may have left deleted files in a hidden folder on the flashdrive... The way I got around that was formatting the flashdrive on Windows, which reset the space to the normal amount. Absolutely don't do that until you back it up, or decide that you don't care about what is on it. You will lose all the data on your flash drive in the formatting. I can't guarantee it will make any difference, but it may be worth a shot. Falconus^{p t c} 05:28, 28 January 2010 (UTC)

I think windows also keeps a "Recycle" folder on flash drives. If you have recently deleted lots of stuff, it might still be lingering on the drive. Try reconnecting it to the PC where you deleted the stuff off it, then empty the recycle folder. Astronaut (talk) 15:45, 28 January 2010 (UTC)

Backup your files then format the usb drive. Should fix the problem. —Preceding unsigned comment added by 82.43.89.14 (talk) 18:30, 28 January 2010 (UTC)

Since someone else asked... I formatted an 8GB PNY flash drive to install Dell's Bootable Utilities Partition. As I did it, I was informed that it will format in Fat16, and the rest of the drive will be unusable until I reformatted it. The problem is, any time I try to reformat it, the max size I get is 1.99GB, even in Fat32. (I tried Windows and Glary Utilities.) Any ideas? Mxvxnyxvxn (talk) 18:20, 29 January 2010 (UTC)

You need to re-partition the flash drive first. Otherwise, you will simply keep re-formatting the 1.99GB partition that the Dell tool created. -- 78.43.93.25 (talk) 13:41, 2 February 2010 (UTC)

EXCEL short cut

Frenz, this is Lawrence. i need to know whether there is any short-cut key to scroll from one sheet to other in ms-excel. can anybody help me? thanks —Preceding unsigned comment added by Johndlawrence (talk • contribs) 03:46, 28 January 2010 (UTC)

CTRL+PAGEUP, or CTRL+PAGEDOWN. More here --Tagishsimon (talk) 04:34, 28 January 2010 (UTC)

Facebook question.

Hello all. I was wondering, do any of you know if it's possible for me to deactivate/remove my Facebook account and still keep the fan pages I created running normally? If I hand over control to someone else, will they still get deactivated along with my account, seeing as I'm the creator? 202.10.94.125 (talk) 04:39, 28 January 2010 (UTC)

A New Undertaking

I`d like to make a site that approximates this:

WARNING: Medical pictures that may be not safe for work, or may be unpleasant to look at - it's a medical "guess the disease" test from the "new england journal of medicine"
http://image-challenge.nejm.org/?ssource=rthome#09172009

in its structure and function.

What would be the easiest way to go about it? Should I learn Javascript? Should I learn flash? or Both?

Or should I give up? I have a basic knowledge of HTML and CSS and a bit of time on my hands!

-Cacofonie (talk) 04:40, 28 January 2010 (UTC)

Forgive me for editing your post, but I clicked your link and just had a lovely picture of a diseased penis appear on my workstation. 218.25.32.210 (talk) 05:09, 28 January 2010 (UTC)

Sounds like you were unlucky - all I saw was a slightly bruised leg..(I modified the warning)

You want to make a site that is similar in layout and style to the site you linked ? if so you need html, css, and yes javascript - that's what the site uses.87.102.67.84 (talk) 13:46, 28 January 2010 (UTC)

You need to learn a back-end scripting language (PHP, Perl, Ruby, etc...) if you want to completely mimic a site like that. -- kainaw™ 14:26, 28 January 2010 (UTC)

Ah! I`m sorry about that! I purposely picked the tamest picture so as not to bother people. I`ve modified the link to a much tamer set. I hope no-one was traumatized. All I would really want to mimic is the zoomable picture, the multiple choice questionaire, and the easy scrolling between questions. Would I need to learn PHP for that? or can I do that all with javascript (including the animated scrolling?).

--Cacofonie (talk) 14:53, 28 January 2010 (UTC)

If you attempt to do it all in JavaScript, it will be a nightmare. Doing it with a backend script (like PHP) will be very easy - assuming you know how to program. I'd also use a database (like MySQL) to make it even easier. Once you have the backend, the content is not part of the page. It is added in dynamically. So, you create the user interface with JavaScript and CSS (the scrolling and such). You will in the pictures and questions with the backend script. You can load a bunch of different picture/question sets by just changing the query for the database. -- kainaw™ 15:06, 28 January 2010 (UTC)

Here's what's going on in the page and what's responsible for it:

• The general layout and appearance: HTML structures the elements, CSS determines how they look.
• The animated bits, zooming, etc.: all Javascript
• The database of images, the recording of votes: a server-side script, like PHP, probably in conjunction with a database, like MySQL.

Now you can cut out some things if you simplify it a bit—e.g., if you are content with a less flashy site, you can drop Javascript. (It could still load up images and look similar, but you'd lose the slick effects.) You could maybe skip out on CSS, and do it all in pure HTML, though the idea makes accomplished web designers squirm. But if you want to record votes, and have dynamically-updated content, you're going to need something like PHP. --Mr.98 (talk) 21:56, 28 January 2010 (UTC)

Strictly, you can write server-side stuff using almost any programming language - I have web pages that are generated on-the-fly in C++ for example. However, I strongly agree that this would be a hard task for anyone who is not a programmer. Step #1 in the process is to learn how to program...if you can't already do that then step #2 starts about a year later! SteveBaker (talk) 05:59, 29 January 2010 (UTC)

Safe Keylogger

Where can I download a free, safe keylogger for personal use? I want to let it run on my computer so that I can create a log of all the keystrokes I enter. Since I will not be using it maliciously or installing it on other people's computer, discretion is not important and its ok if the keylogger runs visibly in the tray or something. Acceptable (talk) 06:10, 28 January 2010 (UTC)

Family KeyLogger, found here. If I remember right, it has a limited trial period, but will continue to run with limited features past that point. It will be visible in the system tray; you will need a paid registration if you ever decide to hide it. If you like it, I would recommend purchasing it, even if you don't need the extra features, to support the company/developers. And it's a deal at only $28 USD. Hope this helps. -^Avicenna_sis @ 10:05, 29 January 2010 (UTC)

Not to doubt Avicennasis, but WOT reports that site to have a "poor reputation", and their website has comments alleging spyarsenal.com hosts malware. See [1]. Thanks, gENIUS101 20:45, 29 January 2010 (UTC)

Just Google Family KeyLogger for several other (possibly safer?) sites for downloading. Dbfirs 07:03, 30 January 2010 (UTC)

Ah. I was not aware of that that, gENIUS. I only remembered this particular program because I myself used it years ago, after seeing as a download of the day on The Screen Savers. OP is probably safer looking elsewhere, but at least I was able to point them in the right direction. -^Avicenna_sis @ 09:16, 30 January 2010 (UTC)

I wonder what exactly you mean to "log" all the keystroke? If you want to just log how many keystrokes you type (and the frequency of each key) and not concerning with what exactly you are typing at an particular moment, Whatpulse is probably what are you looking for. SYSS Mouse (talk) 02:19, 2 February 2010 (UTC)

about the racing car engine

where can i get the details of a racing(F-1)car? I need to know the whole engine working in detail and in simple language —Preceding unsigned comment added by Rohit100 (talk • contribs) 09:41, 28 January 2010 (UTC)

If it's Formula 1 in particular that you're interested in, try this article. You might get a better answer to your question on one of the other reference desks, like Science, Misc or maybe even Maths. CaptainVindaloo ^{t c e} 12:43, 28 January 2010 (UTC)

A formula one car is basically a high performance version of a normal car - for the engine "internal combustion engine" try these [2] [3], for more specific details on F1 try http://www.howstuffworks.com/auto-racing/motorsports/formula-one.htm 87.102.67.84 (talk) 16:51, 28 January 2010 (UTC)

bash filenames and redirecting output

If i run a bash script say, Script [Some Options] Input > Output, is there some way for me to make Output=Input.txt, without me having to know what the input name is, for instance i might want to run sort -un *.dat > (Whatever the *.dat matched to).sort , where the output has been piped to a file named like the input was named but with a suffix at the end (or any other string manipulation i may want to do), Thanks --137.205.124.72 (talk) 14:19, 28 January 2010 (UTC)

What would you want it to do if there were more than one .dat file present? You can sort each such file separately with

for t in *.dat; do sort -un "$t" >"${t%dat}sort"; done

(and that would work fine if there were exactly one). The quotes are to handle file names with spaces etc. There are several modifiers like % that you can use on a variable's value: %#/ are the most useful. --Tardis (talk) 16:20, 28 January 2010 (UTC)

Google Earth

How often does the radar update? Or how do I get it to update?Accdude92 (talk to me!) 16:52, 28 January 2010 (UTC)

If you mean the terrain altitude (relief) information, I believe that all comes from the Shuttle Radar Topography Mission, which is over. So I don't know if they ever update the radar info, other perhaps than fix bugs or plug obvious gaps ion the dataset. -- Finlay McWalter • Talk 17:43, 28 January 2010 (UTC)

No, there is a weather layer, and a subgroup "radar"Accdude92 (talk to me!) 17:45, 28 January 2010 (UTC)

On my copy, it says that it is updated every 5-6 minutes. (Click on Weather -> Information) Titoxd^{(?!? - cool stuff)} 10:35, 29 January 2010 (UTC)

TrueCrypt Recovery Disk

I wish to use TrueCrypt on a system partition. The program requires that a "recovery cd" be made, however the computer I wish to encrypt does not have a cd drive. The recovery disk isn't necessary, it's just a backup, yet the program simply will not continue unless one is made. How can I bypass this step? —Preceding unsigned comment added by 82.43.89.14 (talk) 18:29, 28 January 2010 (UTC)

With the "official" installation, basically you can't bypass it because it's a failsafe. You would need to either plug in a USB optical CDROM drive or download the source code and modify and recompile it not to require the check. Using the USB CDROM method would be the best idea though (you can burn the iso image on another computer, but it needs to be able to "read" it on your computer) and the recovery disk is for your own protection. You say it's not necessary, but it's there in case you ever have a problem with it and using the recovery CD you'll be able to unencrypt the drive (assuming you know the password still). Without that recovery CD, in the event of a problem, there's literally nothing you can do to get the data back. ZX81 ^talk 19:06, 28 January 2010 (UTC)

Won't work, each disk is different. You can't use another computers recovery disk, the headers and password hash will be different

Mounting the ISO file using a virtual CD mounting tool will fool TrueCrypt, I think. If you don't burn a recovery CD right away, you should at least keep the ISO file in a safe place where you will be able to burn a copy if you ever do need it. (The encrypted partition is not a safe place, needless to say.) -- BenRG (talk) 08:03, 29 January 2010 (UTC)

What ISO file?

It makes an ISO file in a temporary directory; you can mount it with a virtual CD utility, or burn it using a different computer as ZX81 suggested. I seem to recall that it displays the ISO file's location in the format wizard. I couldn't remember the details, so I looked in the documentation, and it turns out there's a /noisocheck command-line option that does what you want. You should have read the documentation before asking here, and I should have read it before replying. I still recommend saving the ISO file, though. -- BenRG (talk) 05:29, 30 January 2010 (UTC)

Threat detected and quarantined but site in history

I got a pop-up message from Norton saying it had found and removed a threat. I think the word "quarantined" may have been used. When I looked at the Norton security history I found a series of numbers and letters which I also found when I went to my history to look for a site I had gone to. I never intentionally went to Google-Analytics and yet there it was. Never have I found any site in the history that I didn't go to by clicking on a link or typing where I type the URL. And at home I'm careful where I go. I'm not at home now. By the way, I deleted the history just as a precaution, though by tomorrow the history would have been gone anyway.

What should I tell Google?Vchimpanzee · talk · contributions · 18:36, 28 January 2010 (UTC)

Google Analytics is a web statistics tracking tool. Anyone can embed a GA tracker into their website so that when you go to their website you ALSO connect to the GA server so that they can count the hits, collect data for traffic pattern graphs, etc.

It's perfectly harmless unless you're more than normally worried about privacy. APL (talk) 18:46, 28 January 2010 (UTC)

Well, Norton considered it a threat and I had a false alarm when a company told me I had viruses and demanded I download their software, so these days I'm overly sensitive.Vchimpanzee · talk · contributions · 18:58, 28 January 2010 (UTC)

By the way, those alerts that pop up while web surfing which claim "YOU HAVE A VIRUS! DOWNLOAD OUR SOFTWARE IMMEDIATELY TO CLEAN YOUR COMPUTER!" are all fake, and install malware, or at least install difficult-to-uninstall ad-vomiting software. You can safely ignore them all. Comet Tuttle (talk) 19:23, 28 January 2010 (UTC)

User:Comet Tuttle is referring to WinFixer like pop-ups. Although WinFixer was shut down a little over a year ago, others are still lurking. PCHS-NJROTC ^(Messages) 23:48, 28 January 2010 (UTC)

I know not to download anything unless it's a respected site. The pop-ups in my case came from scan-and-secure07.com.Vchimpanzee · talk · contributions · 18:51, 2 February 2010 (UTC)

Wierd attempts to access port 44281

I noticed today that a DSL IP from Mexico has been trying to access port 44281 on my network, and I'm kind of puzzled why. I'm guessing it's a virus, but why after it continues to fail? Anyone hear of any viruses that behave in this way? I've already contacted the abuse contact for the IP. PCHS-NJROTC ^(Messages) 23:33, 28 January 2010 (UTC)

It may be part of a botnet trying to contact a zombie, or a zombie trying to contact its master. Either way, assuming you're not infected (and the issue is caused because some previous user of your IP address) then there's nothing to worry about. Or it might be a peer-to-peer filesharing program (which occasionally run on weird ports, in part to try to evade blocking) which again is trying to connect to another p2p client which was run by some former user of your IP. Either way, it's probably nothing to worry about. 87.112.52.108 (talk) 23:42, 28 January 2010 (UTC)

I figured it's botnet, I'm just curious which one. I over 50 attempts a week at NAT level, usually coming from residential IPs around the world, but I rarely see any given IP keep trying besides those annoying port 445 attempts on my own CIDR range. PCHS-NJROTC ^(Messages) 23:52, 28 January 2010 (UTC)