Wikipedia:Reference desk/Archives/Computing/2007 February 20

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February 20

Request for assistance

Hello. I am an 84 year old man who has recently acquired a computer. I am currently having some trouble with it and thought I'd ask some of you young people who seem to have a lot of knowledge on computers and the Internet.

Yesterday, I talked to my grandson on the phone, and he told me that I could create a free e-mail address for myself by visiting the Web site "hotmales.com". However, when I do this, homosexual pornography is displayed on my computer. I have two questions: 1. Is there something I must do differently in order to create the free e-mail address? 2. If creating a free e-mail address is not possible, is there some way I can have heterosexual pornography displayed instead of the homosexual one?

I am looking forward to your help. Cargodemonstration 00:10, 20 February 2007 (UTC)

Your question is so amusing I'm wondering if it's a set-up, but I'll play straight man and say: the site you want is http://hotmail.com. (Too bad Gilda Radner isn't with us any more; this'd make a great Emily Litella sketch.) There are lots of free e-mail sites besides hotmail; another one that's quite popular with the "young people" is http://gmail.com. —Steve Summit (talk) 00:40, 20 February 2007 (UTC)

Hehe, what a troll --froth^T 00:41, 20 February 2007 (UTC)

It is hotmail.com. it is easy to use and has enough space to use.

It is a mistake you only make once :-) For whatever kind of porn you like, you can try Google. Interestingly, only 1% of web pages contain porn. Wikipedia has encyclopedic information on these topics at Portal:Pornography and Portal:Sexuality. --h2g2bob 13:33, 20 February 2007 (UTC)

I would like to thank everyone for the help. After quite a few tries, I have now managed to successfully set up an e-mail address at hotmail.com. I also asked my neighbours' teenage son about the pornography issue, and he showed me some Websites I could use for that purpose. This means that both of my problems have been solved. These computers are really a most useful resource. Cargodemonstration 23:33, 20 February 2007 (UTC)

Hah this is rich --froth^T 03:05, 21 February 2007 (UTC)

Limewire driving me nuts

This is not conclusively computery enough for this section, but whatever. Looking up anything on LimeWire brings up lots of things including 'Steven Spielberg gets a hilarious prank phone call', 'Britney_Spears_gets_pranked', 'Track 9', '01 Track 1', etc. All of these have the comment 'not related to: (whatever I searched for)'. I know these are likely to be maleficent, but what exactly are they? I should probably use something else... Vitriol 00:41, 20 February 2007 (UTC)

Don't use limewire. Period. The centralized tracker makes it incredibly easy to get busted --froth^T 02:53, 20 February 2007 (UTC)

Limewire sucks real bad. try switching to imesh instead.

Or just use bittorrent files or something else instead

• The same thing goes on on YouTube. Only in LimeWire there's no central authority to complain to. You can either deal with it or switch programs. - Mgm|^(talk) 10:13, 20 February 2007 (UTC)

Alternative to VNC

I have been using VNC for remote connections. The only problem I faced with this is that if a user knows the VNC password of a remote machine, he can connect to that without the local user of the machine having to accept the session. Of course, there is an option to Prompt local user to accept incoming session but this can be changed either by the local user or the remote user. Is there a way in which this can be disabled? (The local user should ALWAYS be prompted). Alternatively, is there any other software which does the work of VNC but ALWAYS prompts the local user? -- WikiCheng | Talk 05:36, 20 February 2007 (UTC)

Try Remote Desktop which you can find in XP at C:\WINDOWS\system32\mstsc.exe Sandman30s 09:15, 20 February 2007 (UTC)

But remote desktop will log off the local user! I was looking for something like VNC -- WikiCheng | Talk 14:38, 20 February 2007 (UTC)

I didn't think it did without the -console command line option? Cheers, Davidprior 22:01, 20 February 2007 (UTC)

What operating system are you using? --h2g2bob 13:14, 20 February 2007 (UTC)

A mix of Win2k (prof / server) and XP -- WikiCheng | Talk 14:38, 20 February 2007 (UTC)

VNC should be able to do what you need, see here: http://www.realvnc.com/faq.html#hide "Unless the user is logged in with administrator privilages, there is no need to take an additional preventative action to enforce this access control. If the user does have administrator privilages, then these facilities can be disabled using the DisableClose and DisableOptions settings, respectively. See the VNC Server for Windows documentation for more details." Should be fairly straightforward, and the forums there are probably a as good a place here if you get stuck. If your environment becomes all Windows XP, you could consider using Remote Assistance, a feature of Windows XP, which can either be enabled via group policy or requested as needed by the user depending on your environment.Provider uk 20:32, 20 February 2007 (UTC)

At work, I use SMS 2003 Remote Assistance [1] which would do the job, but it is slow Cheers, Davidprior 21:56, 20 February 2007 (UTC)

Provider uk's solution seems to work for me. I added a REG_DWORD with the name 'DisableOptions' with the value 1 and it disabled the 'options' menu in VNC. My users are no so very familiar with windows to change the registry values. Now I can just enable 'prompt local user' and disable the options so that it can't be changed. Thanks a lot everyone :-) -- WikiCheng | Talk 05:35, 21 February 2007 (UTC)

Members Section

I'd like to add a paid section to my site, that requires a username and password to enter. What kind of software does that? Or is it something I could type in myself? Also, what would be the easiest way to link that up with the usernames and passwords in a forum system like phpBB? Black Carrot 06:13, 20 February 2007 (UTC)

• Where is your website hosted? If you Google for "password protected" and related search terms on Google you will find multiple ways of doing this, which mostly rely on what your website provider allows. - Mgm|^(talk) 10:12, 20 February 2007 (UTC)

It's hosted by Globat.com. I've tried to contact their help department, but I haven't heard back yet. Black Carrot 18:46, 20 February 2007 (UTC)

Update: Success. Thanks for the help. Black Carrot 19:37, 20 February 2007 (UTC)

Playstation 2 connection to TV (UK)

Hi, i want to buy a PS2, but the TV i want to use it with only has a UK aeriel socket i.e. 1/2-inch diameter round hole with one pin in the middle. will i be able to connect a PS2 to this tv by way of some sort of adapter or would it be a total waste of money? thank you, --194.176.105.39 08:53, 20 February 2007 (UTC) if you have a PS1 you can use the TV lead from that Jackacon 10:23, 20 February 2007 (UTC)

really? oh that is good news. is the socket in the back of the ps2 the same as that in the ps1 then? many thanks for your answer --194.176.105.39 10:46, 20 February 2007 (UTC)

yes it is Jackacon 14:21, 20 February 2007 (UTC)

spoofed

My registered domain name (call it mydomain.com) allows me to receive e-mail with any prefix, e.g. info@mydomain.com. Recently I've been receiving a large number of failed delivery notifications addressed to random addresses, for example, idfgu@mydomain.com. Obviously some spammer is creating FROM: addresses by generating fake e-mail addresses using mydomain.com. If the e-mail then sent can't be delivered, the notification comes back to me.

How might this have happened? Is there anything I can do about it now?

Thanks for your advice. --Halcatalyst 15:40, 20 February 2007 (UTC)

You can set the FROM header in emails to whatever you want to, and there's really nothing you can do to stop spammers from using addresses with your domain name in them. -- mattb @ 2007-02-20T16:35Z

I assume, then, that the mail does not actually go through the server on which my domain name is hosted? So the domain name is not getting any black marks? --Halcatalyst 16:40, 20 February 2007 (UTC)

Not really, except that the majority of spam recipients will logically assume that the spammer has something to do with your domain. You're not legally liable or anything like that, though. Again, this is unavoidable. -- mattb @ 2007-02-20T16:45Z

Sender Policy Framework and Domainkeys are add-ons to smtp that attempt to prevent this. Diletante 17:09, 20 February 2007 (UTC)

I've owned several domains for quite a few years now and I also thought it was cool that you could tell your friends to send emails to anything@mydomain.com, but quickly discovered that it is definitely more trouble then it is worth. You get so much random spam and junk, I disabled it after only a couple of months, now I only ever set up intentional redirections. Vespine 21:56, 20 February 2007 (UTC)

This is called backscatter by the way. Same thing basically also happens with packets during a DDOS attack Oskar 03:03, 21 February 2007 (UTC)

net working

When USB and ethernet ports of a PC is used for ADSL-Broadband and local intranet repectrively,(when both lan are enabled)

Explorer trying for a internet site times out. Why? Any solution ?

Maybe IE is trying to use the interface not hooked up to the Internet? Splintercellguy 23:21, 20 February 2007 (UTC)

Yeah that sounds likely, have you set up "internet connection sharing" on the PC? even if you are not actually sharing the internet to the other computers on the network you may need to run the set up for the PC to realise that the two conenctions are different. Vespine 00:08, 21 February 2007 (UTC)

Markov Chain in C

The following code picks a letter from char value[] based on the probability weightings in int probability[], which as you can see total to 100. I beleive this is what is known as a 0th-Order Markov Chain. I would like to expand the probability matrix to two dimensions so that I could have a 1st-Order chain. Could anyone provide some way to expand the code to achieve this, or provide suggestions on how I can perhaps generalise / improve the current code even further?

The RNG is simple but adequate enough for my needs (i.e. the weightings are pretty balanced).

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

float getrand(void);

int main(void)
{
    srand(time(NULL));

    int probability[3] = {25, 25, 50};

    char value[3] = {'A', 'B', 'C'};
    int count[3] = {0, 0, 0};
    char b;
    int r;

    while(getch() != 'q')
    {
        r = (int)getrand();

        printf("Random number: %i\n", r);

        if (r < probability[0])
        {
            b = value[0];
            ++count[0];
        }

        else if (r >= probability[1] && r < probability[2])
        {
            b = value[1];
            ++count[1];
        }

        else
        {
            b = value[2];
            ++count[2];
        }

        printf("Value: %c\n", b);
    }

    printf("\nDistribution: %i %i %i\n", count[0], count[1], count[2]);

    return 0;
}

// getrand() returns a random number float between 0 and 100

float getrand(void)
{
    int i;
    float rnum;

    for (i = 0; i < 20; ++i)
        rnum = (float)rand() / RAND_MAX * 100;

    return(rnum);
}

The simplest thing to do would be to declare

   int probability[3][3] = {{25, 25, 50}, {0, 0, 100}, {100, 0, 0}};  //look, a nice loop!

and then do

   int *current_probability=probability[b];

where b has been redefined as

   int b=0;  //index into `value'

because it's easier to deal with the integer internally and just use the characters for output. (Note that for a 1st-order chain, you need an initial condition, so I initialized b to something. You might want to use one step of a 0th-order chain to do that in reality.) Then you use current_probability, which is a slice of your overall array, where you now use probability to check r (by the way, you really want to use a loop for this: just test for r<current_probability[i] for increasing i). Then, since b is an integer now, you don't say

   b=value[...];
   //...
   printf(...,b);

but rather

   b=...;
   //...
   printf(...,value[b]);

Does that help? --Tardis 00:07, 21 February 2007 (UTC)

MediaWiki non-appearing images driving me crazy

I'm trying to get a number of images appearing in the following page but no matter what combination (of upper/lower case), which for the image name is case-sensitive, they don't seem to appear:

• http://treekee.com/tervuren/en/wiki/Draft:The_Art_of_Cooking page with problem
• http://treekee.com/tervuren/en/wiki/Special:Newimages images which ARE there

Any help would be appreciated (I'm sorry, but you will need to create a login to see the wiki code behind the page).

Thanks for any help! 80.200.139.245 17:16, 20 February 2007 (UTC)

You have "%E2%80%8E" in front of some of the links in the HTML code. 0xE2 0x80 0x8E, in UTF-8, is the Unicode Character 'LEFT-TO-RIGHT MARK' (U+200E). You'll have to delete any occurences of that character. --Kjoonlee 19:06, 20 February 2007 (UTC)

In fact, that problem has recently been fixed on MediaWiki; it will silently strip these characters to avoid that kind of problem (and a related but more annoying problem, which is pages with these characters on the title). The change was made on r18513. --cesarb 21:17, 20 February 2007 (UTC)

I noticed the characters get deleted with [[Image:]] syntax, but not when you use <gallery>. --Kjoonlee 19:26, 22 February 2007 (UTC)

That was it! Invisible characters in the image name!! When I clicked "delete" on the place between the ":" and the image name, the cursor did not move (hey, suspicious, if I'd thought to do that). Thanks a lot for your help. I would NEVER have sorted this out without you. 80.201.175.225 20:18, 21 February 2007 (UTC)

Windows Media Player data

Windows Media Player stores various pieces of information about the music you listen to, such has the play count and the most recent play date. Is there any way to get at this data (preferably in a format which can be manipulated in such a way as to use it in a spreadsheet or database)? I've tried typing it in manually from Media Player, but I've got well over 500 songs, which would take far too long to copy by hand. Laïka 17:18, 20 February 2007 (UTC)

Try using plugins. Maybe one of these plugins fit exactly what you're looking for. I don't use WMP, so I can't recommend you one of those, so you might have to look through that list yourself. --Wirbelwindヴィルヴェルヴィント (talk) 03:16, 21 February 2007 (UTC)

They're the sort of thing I'm looking for, but unfortunately neither of the right ones (the middle two) seem to work properly with Media Player 11; the unofficial one crashes, and the Microsoft one works, but won't let me choose which columns to export. Thanks anyway! Laïka 16:01, 21 February 2007 (UTC)

Crazy Linux Tilde Files

I saved a text file on my USB key using Ubuntu (Linux). The file is called ubuntu.txt and is 5kB in size. Why is there also a 3kB file called ubuntu.txt~ ? I think it has something to do with backing stuff up. Why does Linux need to do this? --Seans Potato Business 19:23, 20 February 2007 (UTC)

That file was most likely created by a text editor and not linux itself. It is indeed a backup. -- Diletante 19:27, 20 February 2007 (UTC)

If you were using gedit, you can disable it by going to Edit->Preferences, choosing the "Editor" tab and unchecking the option to create a backup file before saving. grendel|khan 19:30, 20 February 2007 (UTC)

The same for kate/kedit. They save the original with a ~ when saving files. This is not a Linux thing. It is a text editor thing. --Kainaw ^(talk) 19:32, 20 February 2007 (UTC)

emacs also creates a backup files by default. The emacs variable make-backup-files determines whether it saves a backup file. --Spoon! 20:24, 20 February 2007 (UTC)

Strictly speaking, it's not a backup: it's the previous version. Most users likely appreciate having a fallback copy of edited text, just in case the new revision is worse than the last one. This was more important in the old days before multi-level "undo", but it's still possible to exit without knowing you biffed a file, particularly when using an editor like vi or emacs. If you're using a simpler editor, then you may well never want the previous version. —EncMstr 20:28, 20 February 2007 (UTC)

Well thank you all, for the insight and tips :) --Seans Potato Business 21:30, 20 February 2007 (UTC)

Vista UAC

I was wondering what the difference between UAC and sudo is. I hear a lot of complaining about UAC, but I'm not sure how it differs from sudo. For example, with both Vista and Kubuntu, the user is prompted for a password to change the time. So why the complaints about UAC? By the way, I have never used Vista, only read about it. Thanks - Akamad 21:22, 20 February 2007 (UTC)

I used the evaluation version of Vista (until it died - I did blame the software but subsequent events suggest an HDD failure) and now use Ubuntu. I can see 3 problems with UAC which don't exist with sudo:

• UAC provides no protection against someone with physical access to your PC making malicious changes, as it doesn't ask for a passwd
• You often get a UAC confirmation dialogue after you've already answered yes to an "are you sure" question - this is annoying
• Scheduled tasks ask for confirmation (not sure if its part of UAC or another security feature) each time - this led to my AVG ant-virus software not updating nightly at 2am, but waiting till I got up and clicked "Yes"

Cheers, Davidprior 21:54, 20 February 2007 (UTC)

IIRC, UAC only doesn't ask for a password if you insist in running as Administrator. If you run as a non-Administrator user (as you should), it will ask for the password, so in that aspect it's still like sudo. --cesarb 22:04, 20 February 2007 (UTC)

(edit conflict) 7 steps to delete a shortcut. (I know this doesn't happen on the final release, but UAC had already gotten (in)famous enough by then.) --cesarb 21:56, 20 February 2007 (UTC)

I don't know if this is in the final, but RC2 asks you six times (four confirmation dialogs, two privilege-escalation dialogs) if you try to change the extension of a file in the root level of the hard drive. --Carnildo 23:38, 20 February 2007 (UTC)

Just turn it off... --froth^T 03:04, 21 February 2007 (UTC)

BTW, the waaay better HIPS programs are good at preventing viruses and spyware. Try System Safety Monitor (I used a trial of it, it is very good. Until they finished the beta testing :( ). For example, it asks you when something tries to inject a DLL into another process, and so on... not sure if they'll work on Vista, this was ages ago. --wj32 ^{talk | contribs} 10:07, 21 February 2007 (UTC)

SSM prevents DLL injection, but I don't know how it compares to modern HIPS. Prevx appears to scan for exploits like a NIPS/NIDS does, and also prevents certain registry changes. There are stackguards and lockdown tools from other companies. I find HIPS to be too much trouble. Unfortunately I like Outlook Express and Internet Explorer, yet those are among the most insecure programs out there. I hear Vista sort of sandboxes IE, which is something that should have been done long ago. —The preceding unsigned comment was added by 172.146.58.73 (talk) 08:10, 26 February 2007 (UTC).

UAC is a method of making sure you want to use your admin privileges when you already have them. sudo is for elevating your privileges, where you don't already have them. For example, if your anti-virus software wants to use admin privileges to run a virus scan, Windows will pop up with a dialog, asking you if that program should proceed (which is obviously stupid). In sudo, when a non-admin process requests to start an admin process, sudo will ask you for your password. Anything that admin process does is now allowed. No more popups. --wj32 ^{talk | contribs} 10:12, 21 February 2007 (UTC)

If you're running as not an administrator (as you technically shouldn't be) then you actually have to type the admin password to elevate your privileges. I never understood running as sub-root though.. you shouldn't be running any code that you don't trust anyway. I can understand daemons like apache running as nobody in case of a security breach but just take CWD out of your path and make sure you know what you're running and you shouldn't have a problem. --froth^T 19:45, 21 February 2007 (UTC)

This seems to boil down to one of those imponderable personal choice issues, like Coke vs. Pepsi, or Ford vs. Chevy, or whatever. Some users just can't even imagine not giving themselves access to all the power available on what is, after all, their own computer. They think it's insane to run as an underprivileged user some of the time, and to have to jump through hoops (such as su'ing to root) to do "important" things. Other users, on the other hand, think that what's insane and unimaginable is to log in and run as root all the time; this seems impossibly foolish and accident-prone (since accidents as root can be arbitrarily destructive). —Steve Summit (talk) 04:56, 22 February 2007 (UTC)

Even very trustworthy programs - like Firefox - can sometimes get hacked. Running as non-root prevents the bad-ness spreading to your system files. It also makes sure you're not about to do something unutterably stupid - like delete libc - without realising. --h2g2bob 23:32, 21 February 2007 (UTC)

I just found a link to a The Register article on Slashdot, which explains a bit better what's the problem with UAC. It seems that Vista creates the first user account as an administrator account by default (it shouldn't), and that administrator accounts with UAC tend to get annoying popups all the time (I'd guess normal user accounts would get a permission denied instead of the UAC dialog). --cesarb 15:04, 21 February 2007 (UTC)

Pages wont load, when I sign in

This started yesterday. I can sign in, but after that, Wikipedia's pages wont load completely anymore: they get stuck somewhere in the middle. I can see that the login was successful, when I hit stop, but that's about all I can see. I tried signing in as a non-abusive sockpuppet, and also tried accounts on other wikipedias. Same result. I'm using an iBook G4, Mac OS X, and Internet Explorer. What could this be, and what can I do? (Please bear in mind, that I don't know very much about my (or any) computer). ---84.75.111.138 23:33, 20 February 2007 (UTC) (Sluzzelin)

And when you donn't sign in? Vespine 00:07, 21 February 2007 (UTC)

Well, that's what I've been doing, everything works just fine when I'm not signed in. (Except I can't look at my watchlist, can't edit semi-protected pages, and have to confirm I'm not a bot when adding external links.) ---84.75.111.138 01:03, 21 February 2007 (UTC)(Sluzzelin

Well, then it sounds like some sort of scripting or security issue. You are on OSX and using Internet Explorer? As in: "Microsoft Internet Explorer"?? Would you be willing to try Firefox? Or, what's the default one? Opera? Vespine 04:49, 21 February 2007 (UTC)

Safari is the name, and please please PLEASE stop using IE for Mac, it's outdated, and quite a hassel to fix websites for the few of you guys. --antilived^{T | C | G} 05:27, 21 February 2007 (UTC)

Okee, thanks :-) ---84.75.111.138 06:48, 21 February 2007 (UTC)

Web development roles and titles? usability expert? or?

Correct me if I'm wrong...

The Web programmer or Web developer does the PHP, ASP, RoR and database work to make a dynamic website work the way the client wants it.

The Web designer makes the outside look good, graphics, fonts, layout, etc. Is it also the designer who does the basic HTML and CSS?

Then there's the writer, who writes the content. The entrepreneur is the visionary who wants to launch a website for a specific purpose. Even if it's non-profit service, is she still called entrepreneur?

What's the name for a Web specialist who excels at the world of ideas, i.e. the person who can take an existing website and rewrite the content to make it much more clear and succinct and suggest how to reorganize the way it functions from the user's point of view and interface to make it more intuitive and friendly? Is that a "usability specialist" or something like that? It's almost the opposite of the web programmer, because the programmer makes the back-end work, but this person makes the front-end make sense to a human and the most intuitive way a human would want to find the information they need or use it. Would I say "writer and usability expert" or is there a more common term for this kind of conceptual role?

--Sonjaaa 23:46, 20 February 2007 (UTC)

User Interface specialist is a term that gets used, often though, it is not the opposite of the programmer A programmer or web designer who is also a user interface specialist is an asset, a user interface specialist who is not a designer or programmer may not be a very valuable asset, there are a LOT of people who would like to claim they are user interface specialists. Vespine 00:05, 21 February 2007 (UTC)

The person who specializes in teh world of the ideas is known generically as a "consultant". It is a catch-all term but often used in this way. --24.147.86.187 02:14, 21 February 2007 (UTC)

Gigantic websites like microsoft's have teams for graphic design and for layout, but usually it's the same person --froth^T 03:02, 21 February 2007 (UTC)

Who usually writes the spec document? The person who thinks of how everything should function in a usable way and explains exactly how it will work and interact, detail by detail, page by page. explaining it all in english. but then passes it on to the web programmer to do the actual coding and backend.--Sonjaaa 03:13, 21 February 2007 (UTC)

That is usually done by the Web designer, i have 'web designer' friends that do this. The sections in the linked article are pretty relevant to what you are discussing, near the top of the article in the 'website design' and 'issues' sections. Vespine 04:46, 21 February 2007 (UTC)

I thought the web designer was more of a graphic artist who excels at making things look good and doing fancy graphics, rather than thinking logically how things should work exactly from the user's perspective and how to word things? --Sonjaaa 18:00, 21 February 2007 (UTC)

Well, you aren't wrong but I don't totally agree. there are quite subtle distinctions in definitions. In a small website, a web designer can do all of those things. "How to word things" is a different matter entirely because a lot of the time, 'written content' will actually be provided by the business rather then the website design team, unless the business and website is large enough for the website to be a project of the business it self. As a site gets bigger and more complex, certain roles start getting assigned out to separate people. Programmer is probably one of the first, graphic artist at some stage a little later, but definitely sooner then "making things look good" and "thinking logically how things should work". Those things would only need to be separated into different roles on large websites. Vespine 23:21, 21 February 2007 (UTC)