Wikipedia:Reference desk/Archives/Computing/2007 January 11

= January 11 =

On Rewritable CD's
Hello, i was wondering what the best method to use to clear or rewrite a SONY CD-RW650HS (ReWritable 650 High Speed)is. is there any software that i need that doesn't come with the standard windows setup?

sorry this must sound very unintelligent. 142.161.227.58 01:37, 11 January 2007 (UTC)
 * If the CD-RW came with your computer, the software should be there. It's probably Nero Burning ROM. --h2g2bob 01:47, 11 January 2007 (UTC)
 * To clear the disk in Nero, there is an option called 'Erase Rewritable Disk' under the Recorder menu. Sandman30s 08:41, 11 January 2007 (UTC)
 * You can just put the CD in the drive and windows will mount it (chances are as drive D or E). Just delete files and drop files in like any other drive, but make sure you hit Burn in the left column before removing the disk (Windows XP only) --⁪froth T C  02:37, 11 January 2007 (UTC)

Getting an iTunes library from PC to Mac
So I have a new Mac, and would like to get the music from iTunes on my Windows PC to iTunes on my Mac. However, when I plug my iPod into my Mac, the only option I have is to erase my iPod. I'd imagine I'm not the only one who has ever had this problem, and I reckon this is some sort of intentional software roadblock. I'd also imagine that there is an easy way around this (without having to reload all my music CD by CD). Any suggestions? --Jeffrey O. Gustafson - Shazaam! - &lt;*&gt; 06:57, 11 January 2007 (UTC)


 * This page should have the info you are looking for. The itunes software is set to synch your computers with the ipod automatically, so they try to mirror your computers settings with the ipod; so a blank library on the mac would want to make your ipod the same. But you can override the automatic synching and manually do it as the site says--PiTHON 07:06, 11 January 2007 (UTC)


 * That's not really helping me. None of those responses are saying "this is how you do this."  I've got music on my laptop.  That same music is on synched on my iPod.  I don't have music on my Mac, which is the machine I want synched with my iPod.  I want the music on my laptop/iPod to be on my Mac, so I don't have to use my laptop anymore.  How do I do this if iTunes won't let me?  --Jeffrey O. Gustafson - Shazaam! - &lt;*&gt; 08:07, 11 January 2007 (UTC)


 * I appear to have found something... Hopefully this works. --Jeffrey O. Gustafson - Shazaam! - &lt;*&gt; 08:40, 11 January 2007 (UTC)


 * Yea your page is a lot more straightforward, the main thing i was looking for was telling itunes to let you manually control the music, so when you plug it into your mac, itunes wont try to synch the empty mac library with your ipod (erasing it), then you can copy the opposite way (ipod->mac)--PiTHON 02:30, 12 January 2007 (UTC)


 * Windows iPods are formatted with FAT32, while Macs use HFS+. Even though Macs support FAT32, iTunes tries to format your iPod. Copy your original music onto your iPod, say into a folder named "my_music". Then, on your Mac, manually mount your iPod and copy your music over. BTW: please don't ask me how to mount your iPod, I don't use a Mac, I use GNU/Linux. --wj32 talk 07:08, 14 January 2007 (UTC)

Computer System Architecture - Memory Management
Dear Friend,

i'm Sumathi and i'm doing my MCA. i'v the subject Computer System Architecture... i'v encountered the following questions ....pls answer me......

1. How many 128 X 8 memory chips are needed to provide the memory capacity of 4096 X 16?

2. Given a 32 X 8 ROM chip with an enable input. Show the external connection necessary to construct 128 X 8 ROM.

3. A digital computer has a memoty unit with 24-bits per word. The instruction sets consists of 150 different operations. All instructions have an opcode part and an address part. Each instruction is stored in one word of memory. [a]. How many bits are needed for the opcode? [b]. What is the maximum allowable size of memory?

if anybody know the answer kindly answer me or send me to sumi_jana2000 [at] yahoo.com —The preceding unsigned comment was added by 221.134.217.2 (talk) 07:33, 11 January 2007 (UTC).


 * I think the answer is to do your own homework. If there is a specific detail you don't understand about your homework (e.g. how can you determine how many opcodes a 32-bit CPU can have), ask that. Don't expect people here to answer your entire homework. —Mitaphane talk 05:37, 13 January 2007 (UTC)
 * Mmm, question 3 would be bloody easy if you actually learned something from your course... Well, I'll give you some hints. Question 3.a: how many bits are needed to store the number 150? Question 3.b: How much space is left in the instruction after the opcode takes up space? --wj32 talk 07:03, 14 January 2007 (UTC)

About pendrives.
i want 2 kno if there are pendrives with a whopping capacity of about 256 GB. —The preceding unsigned comment was added by Swagat4187 (talk • contribs) 12:27, 11 January 2007 (UTC).
 * No. 4GB appears to be the current maximum. Even 256GB were physically achievable, its astronomical cost would be entirely prohibitive. Adrian M. H. 17:52, 11 January 2007 (UTC)
 * For anything over 200 GB you might consider looking at an external hardrive--66.65.185.43 02:18, 13 January 2007 (UTC)
 * Sandisk released a 32GB flash drive at this year's CES. I believe it actually has an IDE interface, so isn't actually a pendrive.  However, it is one of the largest flash drives I've seen. --Mdwyer 06:23, 13 January 2007 (UTC)

MySQL Data searched by Google & Co?
Greetings! At the time I program the website for the company I work for, particularly a Content Management System with PHP and an underlying MySQL database to store all the articles, news, etc. so even the ladies at the office can put some news on the frontpage without having to ask a software person how to do it all the time.

Well to cut to the point: Being a company website they want to be featured prominently in search engines on their product sector. Of course I will add &lt;meta&gt;-tags for keywords, etc, but my big question is: Do todays search engines search and index dynamic sites, and if they do, do I have to code anything specifically into the site so that google does find the information that is presented (for example) on our news site, where every article is fetched from the MySQL database? Or do I have to output all the MySQL data into a static HTML file every time something is changed in the articles, so that the search engines can index the information?

Any help would be greatly appreciated, and pardon any grammatical errors for I am not a native english speaker. -- Aetherfukz 12:42, 11 January 2007 (UTC)
 * Yes, search engines index dynamic pages as well, as it's impossible to tell the difference in an accurate way. I've been told that Google ranks pages somewhat higher if the content appears to be static (that is, doesn't appear to use parameters - this could be done with some URL rewriting, rather than an actual caching system), but I don't have a source, and I'm not sure if it's really true, since I seem to get fine placements without doing anything special. --Pidgeot (t) (c) (e) 14:47, 11 January 2007 (UTC)
 * And no, google can't index your mysql database directly --⁪froth T C  19:39, 11 January 2007 (UTC)


 * Thanks for the answers. -- Aetherfukz 09:32, 12 January 2007 (UTC)


 * They require hard links to the dynamic pages somewhere on the site — they will not enter terms into a search engine. Also, meta tags for keywords are not used very prominently by search engines these days, because they are obviously easy to abuse. --24.147.86.187 16:41, 12 January 2007 (UTC)

which is the best size for a tablet pc
we all would say that 15 inches is the best for desktops and 14 for laptops. But what is the best size for tablet pcs when you dont use it as a convertible but use only keeping it in your hands and reading? Would you go for 8.4" or 10.4" or 9.4" or 12.1" or 14.1" or 15.1"? —The preceding unsigned comment was added by 59.92.127.55 (talk) 15:32, 11 January 2007 (UTC).
 * I have a 15" laptop and a 21" desktop? I'm 184cm tall. This isn't really a question though is it? You're just asking for people's opinions, you'd probably have more luck at a computer forum rather then a reference desk. Good luck.Vespine 21:54, 11 January 2007 (UTC)
 * I would say it depends on the resolution. My Acer with XGA resolution (1024x786) is 10.4", and having a decent eyesight, I see no point in having a larger screen.  It would only become rather heavy for holding comfortably e.g. while reading Zinio magazines. OlavN. —The preceding unsigned comment was added by 84.236.215.1 (talk) 08:56, 12 January 2007 (UTC).
 * No doubt varies by user. Personally I am looking at 10.4" & 12" models. Smaller ones are a bit hard on the eyes, and the keyboard is too cramped. Larger ones are far too heavy to carry and use as a tablet. Another mutant 07:23, 13 January 2007 (UTC)

sshd for Windows using passwd file
Is there any port of sshd to Win32 that reads the user information from a passwd file or equivalent instead of using Windows authentication? I just want to install a simple server for port tunnelling on a Windows machine without bothering with changing the user settings, etc. N (t/c) 16:18, 11 January 2007 (UTC)


 * Can't remember off top of my head, but have you had a look at cygwin. It provides a unix-like layer on top of windows, so may allow this.  Cheers, Davidprior 19:10, 16 January 2007 (UTC)

Is a PC mouse more likely to be controlled by Bios or a device driver?
82.39.6.25 16:45, 11 January 2007 (UTC)


 * It is always controlled by a driver, even if that driver is often incorporated into the OS. You may be thinking of the mouse/keyboard PS/2 interface, which can be controlled within BIOS. Adrian M. H. 17:48, 11 January 2007 (UTC)

Setting up passwordless (key-based) login on an ssh server I don't own.
I just got a UNIX account on a server I don't own or control. It's running SunOS and OpenSSH ( returns  ). I set up passwordless login by writing to, but is there any way to disable password logins, SSH v1 logins, and so forth? I know about this sort of thing, but that's talking about global configuration, and I'm not the superuser over there.

As a side note, they tell users to login with telnet. telnet! The instructional sheet doesn't even mention using ssh, probably because it doesn't come with Windows. How horrifying. (And yet it's not mentioned for OSX users either, who do all have SSH.) grendel|khan 20:00, 11 January 2007 (UTC)


 * For the first point, disabling password authentication etc., AFAIK there's no way for you to do it, since which authentication methods are allowed is set in the system-wide SSH server configuration (conventionally /etc/ssh/sshd_config) and the only user-writable files that sshd checks are things like authorized_keys and known_hosts. Short of coming up with a dirty hack in ~/.ssh/rc (if there is even a way to detect which authentication method has been used once legged in) I can't see any way of doing what you want without a helpful sysadmin.  And as for them recommending telnet, get yourself a sharpened stick and poke whoever wrote that instructional sheet until they see the error of their ways.  (There are, of course, more practical ways of making the point, but that would be naughty.) -- AJR | Talk 21:44, 11 January 2007 (UTC)


 * It's the instructor for a graduate-level library science course on setting up a website and so forth. Depressing, eh? grendel|khan 18:53, 12 January 2007 (UTC)


 * It might run afoul of their policies, but you could always compile and run your own sshd on the server. Since you're not root, it would have to listen on a port higher than 1024, but other than that you could set it up however you liked.&mdash; Chowbok  ☠  20:49, 16 January 2007 (UTC)

Newb-friendly music apps?
Can anyone recommend a newb-friendly music creating application (software synth, software drum machine, etc) to me? I'm looking to mess around with some, preferably those that allow recording. The platforms available to me are Linux and Windows XP (though I prefer the latter, my Linux machine doesn't like my headphones). Thanks! 202.10.86.63 22:16, 11 January 2007 (UTC)
 * I don't know what the latest versions are like but I always found Fruity Loops pretty easy to use.--Kiltman67 23:30, 11 January 2007 (UTC)


 * MidiPiano Suite contains, a general midi keyboard controllable by your computer keyboard that can record and play .mid files. It also comes with MidiDrum, a rhythm generator using general midi's percussion channel. Get it directly from this link. Main website here. They are both freeware aps, I use them all the time. Besides a few minor glitches here and there, they are pretty reliable. --Russoc4 17:43, 12 January 2007 (UTC)

My system tray battery icon has vanished, and refuses to return
I'm using Windows XP on a Dell laptop (fresh install from the included disc, no crapware), and this problem has only surfaced very recently. The only thing I can recall changing recently was installing PowerStrip. I've tried to uncheck and recheck the option in the Control Panel to enable the icon, but it doesn't help. For now, I'm using another application to put a meter on my desktop, but it's not as convenient. Does anyone know of a solution? -- Consumed Crustacean (talk) 02:35, 12 January 2007 (UTC)


 * I googled your problem and got a bunch of responses from forums and the like (seems to be not an uncommon problem). Check out this thread, they seem to have a lot of suggestions. If nothing there works, go through the googl results. Hope this helps Oskar 06:38, 12 January 2007 (UTC)


 * Yeah, but no useful solutions are forthcoming despite the Google results. The HP forum thread jumps all over the place, but doesn't go anywhere useful. The "Hide UPNP Wizard" might help in a typically crazy Windows style; I'll try it out tomorrow. -- Consumed Crustacean (talk) 06:56, 12 January 2007 (UTC)


 * IIRC, WinXP has some sort of option somewhere (maybe under "Start Menu preferences") to hide unused systray icons. --Carnildo 22:05, 12 January 2007 (UTC)


 * Not it. That's one of the first things I disable ;) -- Consumed Crustacean (talk) 02:50, 13 January 2007 (UTC)


 * I'm not sure which option you mean by "the option in the Control Panel" and the forum link doesn't work, so: Display Properties -> Screen Saver tab -> Power... -> Advanced tab -> Always show icon in the taskbar?  If that's the option you were talking about before, maybe restart between enabling and disabling? —AySz88\ ^ - ^  03:55, 17 January 2007 (UTC)


 * That is the only control panel option I know of, and it failed. I reinstalled Windows, and all is fine again. -- Consumed Crustacean (talk) 07:50, 20 January 2007 (UTC)

General-purpose GUI input to plain text output
This request is a bit broad, so input from multiple people and backgrounds is extremely welcome. What I am looking for is a generic tool that allows me to generate arbitrary text from GUI controls. One way to describe what I mean is by reference to existing apps that *almost* do what I want: What I wonder is if there is a generic tool that allows you to generate *any* kind of text you want (not just SVG, CSS, HTML, source code) with the same methodology, filling in a GUI so as to abstract out parts of the text that are too tedious to do by hand. Any clues on whether this type of functionality exists in any form whatsoever? It seems like all the existing software assumes it will work with only one kind of language, and the GUIs are not extensible (you can't create your own dialogs). NoClutter 03:08, 12 January 2007 (UTC)
 * TopStyle (generate CSS by filling in a "property grid" GUI)
 * Inkscape (generate SVG with many types of GUI stuff, including color picker, gradient drawer, bezier curve tools etc etc)
 * Text editors and IDEs (generate things like source code and HTML tables using only a GUI that specifies how many rows and cols you want, or other parameters)


 * What you want is a scripting language with GUI support. It's possible to write a single application that allowed you to design forms, fill them in, and generate text from them in an arbitrary fashion, but such a system would come very close to being a scripting language with GUI support, so you might as well just do it directly.  If you insist on it being a program rather than a language, Emacs can do what you want &mdash; that is, it has a programming language built in with good support for a variety of text output and it can generate GUIs specified at runtime.  However, its controls (as in GUI components) are simple and not pretty; I don't know how much of a concern that is to you, and it is possible (albeit perhaps more trouble than it's worth) to add your own controls to its suite.  --Tardis 15:37, 12 January 2007 (UTC)
 * Tardis Tardis, thank you for the answer, you understand exactly what I was getting at. I did not know EMACS had this feature, I wonder how many other text editors do. It is tricky to search on this, because "GUI generator" seems to assume the kind of stuff you do with VisualBasic-style form code generator, instead of during the runtime of the editor itself. Scripting is not out of the question though, so these are 2 good leads. NoClutter 02:44, 15 January 2007 (UTC)

I suspect the answer is "no", in two respects.

The tools you mention are, of course, not at all generic; *** content snipped off *** level of the XML document.) —Steve Summit (talk) 21:41, 13 January 2007 (UTC)
 * Steve, thank you, but if you will forgive the remove, but the answer you gave seemed to misunderstand my question, which Tardis already gave a great answer. The tools mentioned were only for analogy, the fact that they are not generic was the point. NoClutter 02:29, 15 January 2007 (UTC)

Adding IR output device to a laptop
I have a portable printer that can use IR (Infra Red) signal from a computer for input. My old (very very old) laptop did that. It had a IR output port so I could print with no wire connecting the computer and printer. The printer also had a parallel port.

My new laptop (actually two years old by now) does not have an IR port and does not have a parallel port. Is there any add on device I can plug into the laptop to give me a IR printer port?67.173.137.132 03:24, 12 January 2007 (UTC) Allen Matthews


 * I'd probably recommend a usb to parallel adapter. From what i remember the IR transmitters have to be like 6 inches a part to work anyway, and directly facing eachother.  But there appears to be usb to infrared adapters as well.  These are just random google pages, but you should be able to find at least the usb to parallel adapter at a computer shop.  Also I'm pretty sure your laptop just had a standard IR port, i dont think theres such a thing as a "IR printer port", so any IR adapter should work..--PiTHON 05:21, 12 January 2007 (UTC)
 * PiTHON is right about the adapters. I use a USB-IrDA adapter with a cable between the USB connection and the Ir module, so that I can aim the device. Fewer wires hanging around, and it is very small. --Seejyb 14:59, 12 January 2007 (UTC)

Latest IT trends
Hi

How can I come to know about the latest trends using Wiki? How are the topics covered? for ex. if my search goes for programming, how would wiki help to me to access the latest developments goin on?

Thanks

Shekhar —The preceding unsigned comment was added by Cmalode (talk • contribs) 10:37, 12 January 2007 (UTC).
 * Wikipedia would probably be a bad source for tech news. Try slashdot. --⁪froth T 18:32, 12 January 2007 (UTC)