Wikipedia:Reference desk/Archives/Computing/2008 June 9

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June 9[edit]

I must be a complete moron[edit]

Can someone explains to me why Gmail Labs have fixed width fonts for reading email but on Google Groups I can't even get fixed width fonts for reading the news group comp.lang.python

Or is there a feature which I cannot find because I'm a complete moron? (talk) 00:02, 9 June 2008 (UTC)

Looks like you have to do it for each page, but still... [1]. Indeterminate (talk) 00:45, 9 June 2008 (UTC)

Programming simple macros with open source program[edit]

Can someone recommend a simple program for programming macros? I just need a macro that pushes down arrow, "alt+e" and kind of stuff. Can a programming language like Perl or Python easily do it too? GoingOnTracks (talk) 00:07, 9 June 2008 (UTC)

You didn't mention an OS, but AutoHotkey is a good open-source macro program for Windows. -- BenRG (talk) 00:16, 9 June 2008 (UTC)
yes, it was Windows. Thanks. How did you guess it? GoingOnTracks (talk) 00:41, 9 June 2008 (UTC)
You can also use Autoit, which can be run from within Perl and Python via the ActiveX component "AutoitX". dr.ef.tymac (talk) 06:58, 12 June 2008 (UTC)

convert command-line program into GUI program[edit]

How can it be done? Is there a open source tool to do it? I have Python and a grasp of it and would like to learn more. I just have to perform easy task with a command-line program in Windows. Like pro.exe -s GoingOnTracks (talk) 00:14, 9 June 2008 (UTC)

Do you just want to run the program from the Windows gui? Because that's not hard... you can just right-click->new->shortcut, and enter the command line as the target. If you want to associate your command-line program with a file type (like .abc), you can do that too.
Alternately, if you really do want to learn GUI programming, you'll need to learn one of the toolkits available for python [2] (or your language of choice). Indeterminate (talk) 00:43, 9 June 2008 (UTC)

Thanks for the prompt answer! I'll try both. GoingOnTracks (talk) 00:45, 9 June 2008 (UTC)

If you know HTML you can create a GUI pretty quickly using HTML Application. dr.ef.tymac (talk) 06:57, 12 June 2008 (UTC)


What does 64-bit mean? I know what a bit is and what a byte is and so on, but what is 64-bit referring to? Also, if I have an Intel Core 2 Duo T7500 processor, does that mean my computer is 64-bit? -- (talk) 02:29, 9 June 2008 (UTC)

May want to read 64-bit and x86-64. That CPU is an x64 (aka x86-64) one, so it is '64-bit'. Others may come in with slightly more detailed descriptions. -- Consumed Crustacean (talk) 03:09, 9 June 2008 (UTC)
(edit conflict) Look, there's an article: 64-bit. Several things can have a size of 64 bits, but when no particular attribute is specified, it usually refers to the size of the processor registers which can be used to reference bytes in memory. That means a process running on a 64-bit CPU can address 2^64 bytes of memory (way more memory than any computer will ever likely have). With a 32-bit address space, the limit is 2^32 bytes (4 gigs). And look, here's another article: Core 2 Duo, which confirms that it is a 64-bit CPU.
Intel processors have for a long time had the ability to do 64-bit arithmetic (add, subtract, multiply, divide) by using a pair of 32-bit registers as input and/or output. And floating-point math has been at least 64-bit for even longer. But without the ability to use a 64-bit number as a pointer to a memory location, those processors would never have been called "64-bit". --tcsetattr (talk / contribs) 03:20, 9 June 2008 (UTC)
According to Intel Core 2 Duo, it is indeed a 64-bit processor. JeremyMcCracken (talk) (contribs) 02:32, 12 June 2008 (UTC)
So is 64-bit better than its 32-bit counterpart?

Dial up connection for CDMA Telephones[edit]

I created the dial up for CDMA in FEDORA CORE,when actvating the modem, the phone dials HSPD call,but disconnects in a moment, Why?, Please help.... —Preceding unsigned comment added by (talk) 03:53, 9 June 2008 (UTC)

Does the modem work with POTS wired telephone lines? Kushal (talk) 09:31, 9 June 2008 (UTC)
I have never seen a cellphone (cellphone modem), which could be connected to POTS wired telephone line. -Yyy (talk) 08:34, 10 June 2008 (UTC)
Does it works in other operating systems? (if available). Does your cellphone contract (or whatever terms of service) includes HSPD? (or any other data services). Does the call connects and then disconnects, or it fails to connect in first place? Does your dialer (program that dials the modem and maintains ppp connection) produces any error messages (or writes any error messages in log)? -Yyy (talk) 08:34, 10 June 2008 (UTC)

Buying an email address[edit]

There is an email address I would like to have (say, which is already taken. I would like to buy it from its current owner. However, I can't find any guides online on how to go about this in an effective manner. Does anybody have any suggestions? Thanks in advance. -Anonymous —Preceding unsigned comment added by (talk) 05:09, 9 June 2008 (UTC)

Just send an email to the email address saying you want to buy it off the owner and hope for a reply? --antilivedT | C | G 05:46, 9 June 2008 (UTC)
I believe that selling email addresses is against gmail's terms and conditions, not that they are likely to find out. -- Q Chris (talk) 07:58, 9 June 2008 (UTC)
One small thing to iron out is to know what the secondary email address was and change it if possible. Just in case the previous 'owner' wants to change your password, just for fun. Kushal (talk) 09:30, 9 June 2008 (UTC)
What about the price? Should I ask the current owner for a price, or should I offer one? And if the latter, how much? Thanks -Anonymous —Preceding unsigned comment added by (talk) 17:43, 9 June 2008 (UTC)
Depends on how much you are willing to pay for it and how you anticipate the bargaining to go. Kushal (talk) 21:00, 9 June 2008 (UTC)
You could just use a modified version, such as and save yourself the trouble. --Alx xlA (talk) 03:57, 10 June 2008 (UTC)



I'm trying to get a squid proxy working for https, like this:

[ me ] ---- http or https (don't care) ----> [ proxy ] ---- https ----> [ website ]

Squid's compiled with --enable-openssl and works fine for http requests, but gives "protocol error" for https requests. I've got self-signed keys set up like this

https_port 3129 cert=/.../squid_proxy.crt key=/.../squid_proxy.key

though I think this is only from me to the proxy? I'm trying my requests like GET https://some_website.example over HTTPS (using python's httplib class). This is just on localhost at the moment.

Are there any good tutorials for this sort of thing, or are there some useful pointers as to what to do? --h2g2bob (talk) 14:29, 9 June 2008 (UTC)

SSL/TLS is supposed to provide end-to-end encryption. The endpoints ("me" and "website") are not supposed to trust anything in the middle, including a squid. When done correctly, the proxy will not even know what URL you are requesting, and will only have minimal knowledge (IP address and port) of the server you connected to. How it's done: HTTP CONNECT. You tell the server "CONNECT" and it makes the connection for you. Then you start doing your SSL/TLS negotiation with the server, and the proxy just passes the data through without attempting to parse it (which it can't do anyway because it doesn't know the secret keys). After the SSL/TLS setup is complete, you send your HTTP request and read the HTTP response. That's the operational summary; as for how to do it quick and easy in python, hopefully someone else will answer. --tcsetattr (talk / contribs) 20:17, 9 June 2008 (UTC)

Are multiple backup of encrypted data easier to decipher?[edit]

If I am encrypting (with TrueCrypt, for example) my data (a spread-sheet, for example) every week and doing a backup of it with the same password, is this set of files that are almost the same easier to crack than a single file? GoingOnTracks (talk) 17:31, 9 June 2008 (UTC)

I don't think so—the length of the file should have nothing to do with it. In either case the file is going to be broken up into smaller cipherblocks, it's just a question of how many there are per file, I believe. And if you could break one of them, you'd know everything. But you can't do that (assuming you've chosen a passphrase not susceptible to simple dictionary brute force attacks). -- (talk) 17:48, 9 June 2008 (UTC)
I think it is always going to be the case that the more sample data you get the easier a cypher is going to be to crack, and especially if something is known about the plaintext. The worst might be if an attacker can actually inject plaintext for you to encrypt, but it doesn't sound like that is the case. If the samples are relatively sparse, an attacker can't purposefully inject their own plaintext, and the plaintext (and the differences in plaintext between the samples) is unknown, I can't imagine it would reduce your security very significantly.
If you are really worried about it you could probably use a one-time pad on the data itself and include the pad as a prefix/postfix to the "plaintext" stream going into your cypher. That way the input data would look pretty random each time and it would be difficult looking for similarities between encrypted versions. With a stream cypher a random prefix might even do the trick by itself, without the need to use it as an initial pad. --Prestidigitator (talk) 20:11, 9 June 2008 (UTC)
There's no reason to bother. TrueCrypt is completely secure against known-plaintext attacks and adaptive chosen plaintext attacks and all other attacks on the encryption. It's possible there's a flaw in the design but I don't think so. A previous version was vulnerable to a chosen plaintext distinguishing attack (i.e. the attacker could tell that the volume was a TrueCrypt volume, not actually read the data), but that's been fixed. That doesn't mean TrueCrypt will keep your data secure, but you shouldn't worry about the encryption side of things. The dangers are things like a weak passphrase (which can be brute-forced) or malware running secretly on your computer or files left over in an unencrypted temporary directory. Whether those risks are relevant in your case depends on who you're trying to hide your data from. -- BenRG (talk) 00:05, 10 June 2008 (UTC)
As far as I know, in theory, the more encrypted data you have, the "easier" to crack it gets, this is one of the "basic rules" in cryptography, off course this does not mean your data will be easy to crack... In fact, it should be very hard to crack if you use something like TrueCrypt, here we are just talking about minimal differences, if you are careful, your data should be extremely difficult to crack, even if you have lots of files SF007 (talk) 13:40, 11 June 2008 (UTC)

Wiki-ness of a wiki[edit]

When does a wiki stop being a wiki? Does anything that runs on MediaWiki automatically qualify as a wiki? What if editing is blocked to everyon but one or maybe two people? Our article states, "A wiki is a collection of web pages designed to enable anyone who accesses it to contribute or modify content, using a simplified markup language." But if no one can edit the pages, or act collaboratively, is it still a wiki? Mahalo nui loa. --Ali'i 18:51, 9 June 2008 (UTC)

Do you mean all pages have full protection, cascading protection or something like that? Kushal (talk) 20:57, 9 June 2008 (UTC)
I think the question is about personal wikis and similar closed "wikis" who can only be edited by one or a small group of people. In these cases, the distinguishing feature seems to be the ease of editing and linking between pages. « Aaron Rotenberg « Talk « 21:12, 9 June 2008 (UTC)
Yeah, or say I just decide to start a wiki, but then disable account creation and turn off all non-logged in edits. That way no one but myself can edit it. Is it still a wiki? Wouldn't that just kind of make it a regular non-wiki website? --Ali'i 21:13, 9 June 2008 (UTC)
No. The distinguishing feature of a wiki is that it makes web pages read/write for authorized users, rather than the standard regular non-wiki website's read-only. How you choose to define "authorized users" doesn't change that. --Sean 22:24, 9 June 2008 (UTC)
Any web site can be edited by its owner(s). Does that mean that all web sites are wikis? Perhaps more specifically, plenty of blogging software allows editing of existing posts - does that make them wikis? If you include the "ease of linking" criteria, these cases largely go away. « Aaron Rotenberg « Talk « 01:19, 10 June 2008 (UTC)
Plain old web pages are not "designed to enable anyone who accesses it to contribute or modify". See paradox of the heap for borderline definitions. --Sean 12:59, 10 June 2008 (UTC)

Password protecting web directory[edit]

I need to password protect files in a given web directory (say, ~/www/files), but I don't have any way to put files into anything but my main www directory (say, ~/www). From what I can tell, this rules out using .htaccess, yes?

Is there another solution to accomplish something like .htaccess protection? It doesn't have to be totally rigorous, just something that will keep people from downloading files in the directory unless they are a select group of folks with a password. -- (talk) 20:07, 9 June 2008 (UTC)

I believe you can use .htaccess to protect subtrees (pretty sure Apache does this), but it is going to depend on the web server you are using, and may have to be explicitly allowed in the web server's configuration files. (EDIT: Oh. Oops. Missed the part about where you can put the files. Don't know about that one, but it should be pretty clear from the web server's help documentation.) --Prestidigitator (talk) 20:14, 9 June 2008 (UTC)
For Apache, see the Apache authentication and authorization how-to for a good starting point. --Prestidigitator (talk) 20:23, 9 June 2008 (UTC)
I should also have noted that I don't have shell access at all. Just FTP. And I can't modify any of the server settings. (Sigh.) It does have some PHP capabilities, but a lot of things are disabled (and, believe it or not, the entire filesystem is read-only, so no PHP script can do anything but read files. WTF academic IT departments, why you gotta be such a pain in the ass.) -- (talk) 20:30, 9 June 2008 (UTC)
Um if the filesystem is read only then how do you upload with FTP? .froth. (talk) 22:29, 9 June 2008 (UTC)
I can upload from FTP, but that's it. As for how they implement the read only aspect, no clue. It's clear that PHP in any case does not have the permissions to modify files; I inquired and they told me it was a read only filesystem or something like that. -- (talk) 03:55, 10 June 2008 (UTC)
I think PHP and Apache runs as nobody, so the files must be set to "writable by all". --grawity 11:28, 10 June 2008 (UTC)
Right. But I can't change the file permissions. That's not the current problem, though. There's no way around this read-only business (other than doing weird things by automating FTP connections). -- (talk) 16:52, 10 June 2008 (UTC)

Flickr: What's the catch?[edit]

FlickrPRO seems to give unlimited uploads and storage, unlimited sets and so on. What is the catch? Is there a reason to not get FlickrPRO? They even say they will retain all the pictures in case someone drops the subscription and joins again later. Kushal (talk) 21:07, 9 June 2008 (UTC)

There is no catch except the cost. You pay for the service yearly. JoshHolloway 21:20, 9 June 2008 (UTC)
Unless you consider a 20 MB picture filesize limit and a 90-second video length limit catches. Xenon54 21:27, 9 June 2008 (UTC)
Hard drive space is cheap, bandwidth is relatively slow. Most people who sign up for the service will probably not use anything close to the maximum amount of data that their ISPs would let them upload anyway. -- (talk) 21:35, 9 June 2008 (UTC)
Hmm, thanks. I don't think I will own a camera that has an output of 20 MB image in lossy jpeg [in the forseeable future] and there is Google Video for uploading videos. However, I agree that I need to see how much of the "unlimited"space and bandwidth I will use. Afterall, I cannot just spend all my time taking pictures and uploading them to flickr, can I? Kushal (talk) 21:52, 9 June 2008 (UTC)

windows Xp on Vista laptop?[edit]

My brother bought a dell PC with windows XP a few years back, and it came with microsoft office XP. He's in the process of buying a laptop, and heard horror stories about vista. Can he use the old win XP install disk on his laptop, or will there be some sort of driver incompatibility problems?

Also, he's aiming for cheap. If the above fails, can he install office XP on a vista laptop?

thanks --Shaggorama (talk) 21:33, 9 June 2008 (UTC)

WHen buying a new PC with the operating system included it is only licensed for that box. So he won't be able to activate the license on a completely different machine, although it may be physically possible to install. One thing to watch out for is all the drivers for the laptop that may have different vista and XP versions. Graeme Bartlett (talk) 21:56, 9 June 2008 (UTC)
Ah- but Vista now has downgrade rights. [3] --—— Gadget850 (Ed) talk - 22:07, 9 June 2008 (UTC)
But does OfficeXP work on Windows Vista? I am not sure. By the way, you can always use so this should not be a major problem. Kushal (talk) 22:47, 9 June 2008 (UTC)
According to Microsoft Office, Office XP works on Vista. -- Meni Rosenfeld (talk) 23:18, 9 June 2008 (UTC)
I have Vista on my laptop, and Office 2003 works just fine. Leeboyge (talk) 06:10, 11 June 2008 (UTC)

Automatically mount data CDs in Kubuntu[edit]

How do I set Kubuntu to automatically umount /media/cdrom when the drive tray is opened, and mount it when the tray is closed? NeonMerlin 22:03, 9 June 2008 (UTC)

.RAR Help[edit]

I was trying to download a video clip off of RapidShare that's in .rar format, but try as I might I can't :( . I tried to use WinRAR but after about two hours of going nowhere, I was wondering if anyone could give me directions? (Error text @ To me the errors make a loop by directing me to extract volume two to extract volume one when volume two needs volume three to extract volume two and volume three needs volume one for extraction. Anyone else ever had this happen/know how to solve it?

I know it's because rapidshare has a 100MB limit so it had to be broken into three sections, I just can't get the sections to work. MANY thanks! Yamakiri TC § 06-9-2008 • 22:34:15

Do you have all the volumes together? To me it sounds like it is trying to extract all at once, but it can't find the component pieces. -- (talk) 16:50, 10 June 2008 (UTC)
Yup, I've got all three. Yamakiri TC § 06-10-2008 • 19:34:58
Hmm... the names of the sections match what the error message says WinRAR is looking for? JeremyMcCracken (talk) (contribs) 02:37, 12 June 2008 (UTC)

DDR2 vs. GDDR3[edit]

For the exact same card with the same amount of memory that comes in both a DDR2 and a GDDR3 version (such as the 8600GT and HD 3650), is there a big gap between performance? There seems to be a $10-20 price difference for the two versions. Will GDDR3 offer better performance at higher resolutions or something?

And if there's any benchmarks between a DDR2 and a GDDR3 card, could you post them here? Thanks (talk) 22:55, 9 June 2008 (UTC)

For what it's worth, my guess is that there will be no significant difference. -- Meni Rosenfeld (talk) 00:31, 10 June 2008 (UTC)
But aren't most stock GDDR3 clocked higher though? (talk) 00:39, 10 June 2008 (UTC)
If GDDR3 is anything like DDR3, then the higher clocks will generally be accompanied by higher latencies. Depending on whom you ask, this can either partially or fully offset their advantage. It is also not very clear how much of a bottleneck is memory in a card like 8600GT. Again, I'm just guessing here.
In any case, I wouldn't really recommend the 8600GT. There are some much more powerful options available for similar prices (9600GSO comes to mind, but the specifics depend on your requirements). -- Meni Rosenfeld (talk) 14:28, 11 June 2008 (UTC)


i have a new laptop with windows vista. can i dual boot vista with linux or is it too late? if i can then how would i do it? and what is a good version of linux for somebody who never used it before?-- (talk) 23:04, 9 June 2008 (UTC)

It's not too late, by any stretch. I'd suggest trying out Ubuntu as a starter, as it's a very simple and easy to install. You may want to consider using a virtual machine in order to try it out from within Vista before going the whole hog and installing a dualboot system. Hope this helps, Gazimoff WriteRead 23:16, 9 June 2008 (UTC)
A virtual machine? Wouldn't it be simpler to use Wubi? -- Meni Rosenfeld (talk) 00:29, 10 June 2008 (UTC)
It depends. A VM will let you try out an operating system with little risk, as you're unlikely to repartition your hard drive or break anything. They're also usually easier to get working as they imitate very standard hardware profiles. I find it very handy when trying out a new OS for the first time, as you can have the VM in one window and the help files, manpages or support website open in another. Once your confidence is built up, you can then go for partitioning.Gazimoff WriteRead 15:26, 10 June 2008 (UTC)
Wubi doesn't partition anything either. It installs an OS on a file on the existing Windows partition, then puts an entry in the Windows boot configuration so that it shows up in the boot menu. Uninstalling is done easily through Windows. No mess, no risk. -- Consumed Crustacean (talk) 22:20, 10 June 2008 (UTC)
Check what partitions you have...If you have an unused partition, install Linux in that. And Ubuntu is the best distribution for beginners. --User:Masatran —Preceding unsigned comment added by (talk) 15:22, 10 June 2008 (UTC)

PayPal Account[edit]

Can I receive money, send money, and make purchases via PayPal if my account is unverified and doesn't have a bank account or credit card attached to it? —Preceding unsigned comment added by (talk) 23:14, 9 June 2008 (UTC)

No you can't, because that'd be a huge security risk! Yamakiri TC § 06-9-2008 • 23:24:21
I what's the minimum amount of info I can have on an account before it will allow me to make purchases with money that has been sent to me from someone else? (can I receive the money sent by someone else?) Thanks for your response. -- (talk) 23:29, 9 June 2008 (UTC)
This seems like a question you need to ask of PayPal. Call them at 888-221-1161 in the US. -- (talk) 14:32, 11 June 2008 (UTC)