Wikipedia:Reference desk/Archives/Computing/2007 August 3

Welcome to the Wikipedia Computing Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

August 3

Programming

I want to learn how to program. I already got some (very basic) basics down, but I really don't know much in effect. What language should I start with? How should I learn? I don't plan on taking classes too soon (well, why would I be asking then?). --hello, i'm a member | talk to me! 00:43, 3 August 2007 (UTC)

A lot depends on what your goals are. Some might recommend Lisp, for example as the best language to start with. I think I might lean towards Ruby as a starting language, or perhaps Java. But really, it all depends on where you'd like to go with your programming. 65.91.98.102 00:53, 3 August 2007 (UTC)

Python (programming language) Is also a widely recommended first language and my personal favourite. It is very easy to start with IDLE (Python). Vespine 02:22, 3 August 2007 (UTC)

Personally (and this just from my own experience teaching myself and others) I think that you should start with a language that is designed with simplicity and ease of use in mind, while still being somewhat powerful. Your programs wont be very useful perhaps, but they will be fun as hell to do (if you're in to that kind of thing). Luckily, such a language exists, and it's called BASIC! I heartily recommend downloading the qBASIC environment if you can find it (I have fond memories of drawing mandelbrot sets in tiny resolutions in a DOS environment). After that, a c-style language would be good. Java is nice, because it gives you a solid introduction to object-orientation. But you really need something simpler so you can learn all about loops, if/then/elses, sub-routines and functions. --Oskar 08:08, 3 August 2007 (UTC)

I would argue that, given the clear movement towards object orientation as the programming model of choice, it makes more sense to start with an OO language for most people who want to learn programming. 65.91.98.102 18:50, 3 August 2007 (UTC)

True, but there are OO ways to do BASIC. VB.NET is OO, as is RealBasic, and both are pretty striaghtforward. Personally I would go with PHP over QBASIC, since it isn't really any harder, the syntax is more standardized, and you can actually make something recognizeably impressive with PHP (QBASIC isn't going to impress anyone, these days). --24.147.86.187 17:17, 4 August 2007 (UTC)

Command Prompt

Hi! The schools in my state have recently tightened controls on their network and so now the trusty command prompt has been disabled. When it is opened up in the text display area it states that 'The Command Prompt has been disabled by your administrator'. Does anyone know of how I could gain use of it? ThanksMix Lord 01:22, 3 August 2007 (UTC)

Why do you want to use it? Unless you want to run command prompt apps or some network tasks, you can pretty much do everything else through the GUI (some tasks are far more difficult, but at least you get it done). Besides, it's blocked for a reason. Anyways, try copying cmd.exe from your home PC and try transferring it to the school PC, or simply try running it from 'Run'. (Very) low chance these will work, but trying always helps. Really, you're best off either trying to login as admin or not attempting to use it at all. --hello, i'm a member | talk to me! 02:17, 3 August 2007 (UTC)

If it is disabled by network policy you won't be able to run it, unless you get elevated rights on your user ID. Vespine 02:18, 3 August 2007 (UTC)

Someone seems to have also disabled the run function on the computers as well, so I guess I'll just have to give up. Thanks anyway.  :(

Mix Lord 06:26, 3 August 2007 (UTC)

Try a shortcut to cmd.

Cool. How do you do that?

My technique is to launch command.com via Internet Explorer or Microsoft Word web bar. Splintercellguy 07:53, 3 August 2007 (UTC)

Create a shortcut to somewhere you can write (like your documents, if you're permitted to save to the machine), and have the target as cmd.exe. The above suggestion has also worked for me in the past.

It wouldn't work. If the command prompt is disabled using network policies then no matter how you run it (it is apperent that the OP has access to cmd.exe in order for him to run it and see the message anyway). command.com might work, but there's not definite answer since we don't know the policies. --antilived^{T | C | G} 11:09, 3 August 2007 (UTC)

I have tried this on a system that barred the execution of cmd.exe in the same manner as the OP, though his system might differ. Splintercellguy 16:54, 3 August 2007 (UTC)

I was referring to the shortcut method. command.com worked for me is well for some, but some others doesn't even have command.com in system32 so that's a no-no. Haven't tried using an external copy though... --antilived^{T | C | G} 00:18, 4 August 2007 (UTC)

Yes, if the command prompt is disabled using network policies. But that may not have been the case!

Does anyone know of a valid security-related reason for taking this approach? I'm no expert on Windows, but its command prompt is and has always been pretty wimpy, and I don't know of much you can do with it that you can't do via the GUI, and certainly nothing dangerous or security-impairing. (What disabling the command prompt is impairing to, of course, is productivity, because as User:Member correctly notes, some operations are terribly cumbersome via a GUI. To a power user, being without a CLI isn't merely inconvenient, it's devastating.) —Steve Summit (talk) 00:37, 4 August 2007 (UTC)

As long as the user doesn't have admin they can't really do anything damaging with DOS. It just soothes the savage admin's ego. --froth^t 02:51, 4 August 2007 (UTC)

Dude, you can access the registry through commands. Having a command shell is hella useful for getting around blocked GUI items. In my experience, the thing to do was limit yourself to the DOS emulation through command.com, but you might be able to use bash out of Cygwin or import Powershell on a thumbdrive.--Alph Tech STUART 17:26, 4 August 2007 (UTC)

Dude, if the registry needs to be protected, a real operating system would protect it by... protecting it, not by trying to hide or disable all the commands that might let you alter it. (Unless I'm mistaken, you can access the registry through GUI tools, too.)

If there are are graphical programs that need to be "blocked", the right way to keep them from being invoked is to remove them from the system entirely, not to "disable" them from graphical invocation, leaving them still invokable if someone can sneaky find his way to a command line. (But actually, neither disabling nor removing them is the right approach, because someone could always install their own copy, or run them off of removeable media.)

If your approach to security is to try to limit which programs users can run (and remember, command.com is just another program), your security is always going to have all the attributes of a rusty sieve. Real operating systems implement security by arranging that critical resources and tasks require permissions, and then carefully control the doling out of those permissions. Controlling security by controlling access to "magic programs" is like securing vaults with magic words -- once someone learns the magic word, you're sunk. —Steve Summit (talk) 17:43, 4 August 2007 (UTC)

Dude, you're preaching to the choir. There are better ways to secure a system, but most high schools aren't trying to do more then keep the kids off of porn and out of their grades. --Alph Tech STUART 00:03, 6 August 2007 (UTC)

Thanks. Yeah the registry, control panel, task manager and C drive have all been disabled, I was hoping to still have some control over it, and nowhere in my school's computer use policy does it say anything about trying to get past restrictions like that. It's not like I'm trying to hack it or anything. Mix Lord 23:23, 5 August 2007 (UTC)

Uhh, the C drive is disabled? How so? --Alph Tech STUART 00:03, 6 August 2007 (UTC)

Probably just not in "My Computer", that's not uncommon in a windows user network, "My Documents" is the user space in such a system. Vespine 02:17, 6 August 2007 (UTC)

Bittorrent trackers

I have some material which I would like to make available using bittorrent. There are no copyright problems, and I would like to place the tracker on a server which has a high likelihood of remaining online for a while, and whose reputation is not too badly tainted. I read the article Bittorrent tracker, but it is not clear to me which of the sites listed that is best suited. I would be grateful for reccomendations. --Divulgación de ciencia 09:05, 3 August 2007 (UTC)

I seriously doubt that there is such a thing. It would be impossible a tracker to ensure that all the content shared is be legal if they are open to the public. If you don't want to host the tracker yourself, I'm afraid that the regular open trackers are what you are stuck with. I would just go with the pirate bay tracker ( http://open.tracker.thepiratebay.org/announce ), it will certainly remain online for quite some time. Remember that you are not doing anything illegal, so don't feel guilty :) --Oskar 09:27, 3 August 2007 (UTC)

Thanks. How do I go about to host my tracker myself? Is this a functionality which is included in bittorrent clients, or do I need a web-server or what? --Divulgación de ciencia 12:40, 3 August 2007 (UTC)

What does it matter if its "reputation is tainted?" Those are the ones that people use, and if you don't want to be seeding for the rest of your life you need other people around to seed. To get other people to download your torrent you'll have to list in on an index or search engine... the most popular ones are ones operated by a bittorrent tracker! So you might as well just let your torrent be tracked by the same site you submit it to be indexed. I'd recommend using thepiratebay and demonoid (if you have an accout there) and setting up your torrent file to use multiple trackers. That way you get maximum exposure and maximum reliability in the unlikely event that either of them goes down permanently. Also you can try making a trackerless torrent with utorrent or the original client (NOT azureus) but the bittorrent dht network isn't exactly the most efficient way of finding peers and most bittorrent searches don't accept decentralized torrents. You can track it yourself too if you want but for a single torrent file that's definitely overkill, it's provided as a free service by the big trackers (and their servers are much better than anything you could afford) --froth^t 13:24, 3 August 2007 (UTC)

Also keep in mind that there are tons of legitimate torrents on sites like thepiratebay, don't feel uncomfortable about using a "warez site" to distribute your legitimate wares. --froth^t 13:26, 3 August 2007 (UTC)

utorrent has a builtin tracker. Tracker can be enabled at options/preferences/advanced/bt.enable_tracker. (this must be set to true) If enabled, it has announce url of http://client_ip:port/announce, where client_ip is ip address of computer running utorrent, and port is incoming connections port (usually random assigned during startup, but can (and in this case must) be set constant). IP adress must be static (or tracker will not be available) (can use dynamic dns). utorrent computer does not requires .torrent file, it is tracking. This method is fairly unpopular, partially because of requirement of static ip and port. Using this method, there will be necessary seperate mechanism of .torrent files distribution. -Yyy 14:39, 3 August 2007 (UTC)

you may be able to get it indexed by certain trackers that allow "external" torrents. Also remember to check if your computer is reachable from the outside- forward the proper ports on your router. And like yyy said, use dyndns --froth^t 16:22, 3 August 2007 (UTC)

Thank you all for your advice! --Divulgación de ciencia 20:13, 3 August 2007 (UTC)

Pentium D and Pentium Dual Core Difference

What's the difference between pentium D and Pentium Dual-core processor???

This is an encyclopedia. You could check the article Pentium D and quickly see that the Pentium D is one type of Pentium dual-core processor. -- Kainaw^(what?) 12:32, 3 August 2007 (UTC)

802.11, wi-fi, etc. Data link layer

Is here any article, which would contain data about 802.11 data link layer? It differs from ethernet data link layer. There are multiple articles about physical layer. -Yyy 14:43, 3 August 2007 (UTC)

Try 802.11 or Wi-Fi_Technical_Information

IEEE 802.11 and Wi-Fi Technical Information contains only data about physical layer (frequency band and modulation schemes are part of physical layer)(data link layer would be framing structure and collision avoidance, (WPA and WEP, probably also)). Article wi-fi contains very smal amount of any technical information. -Yyy 08:47, 5 August 2007 (UTC)

Archos 604

According to our article on Archos, the Archos 604 and 704 video players come complete with Wifi. What exactly does a portable video player do with wifi?--172.146.223.125 14:58, 3 August 2007 (UTC)

According to previously mentioned article, it uses it for: web browser; access to local network, to transfer and files (media files)(or play directly from network) . -Yyy 15:05, 3 August 2007 (UTC)

iTunes video syncing problem

I just recently got a new iPod, and as I started syncing my videos, I came across some videos that were in the correct format (proof), would play in iTunes, but were not allowed to be copied to the iPod (proof). What is wrong and what can I do to fix it? —Akrabbim^talk 15:18, 3 August 2007 (UTC)

I believe Apple has a fix for this on their website for vista users.

Their fix is for iPod hard drive corruption. The problem here is in the file I believe. Anybody else know what to do? —Akrabbim^talk 21:09, 3 August 2007 (UTC)

What are the file types? iPod cannot play Quicktime .mov, but iTunes can. Same with AVIs. --72.202.150.92 03:00, 5 August 2007 (UTC)

The files are .mov, which shouldn't be a problem, because I have other .mov files on my iPod with no problem. Even then, when I try to convert them using iTunes, it says it is in the correct format, even though it won't sync. —Akrabbim^talk 12:13, 5 August 2007 (UTC)

Norton AntiVirus 2007 Addition Error

Hello. When my Full System Scan finishes, I click on the plus sign beside "Total items scanned", giving me information on how many files were scanned of each type. Today, Norton AntiVirus shows me the following:

  Total items scanned: 301823
  - Files & Directories: 298903
  - Registry Entries: 157
  - Processes & Start-up Items: 2547
  - Network & Browser Items: 206
  - Other: 5

If you do the math, the sum of the files scanned (Files & Directories, Registry Entries, Processes & Start-up Items, Network & Browser Items, and Other) is five less than what Norton AntiVirus claims. So I export the results. I open the notepad file that has my exported results, finding that the "Total items scanned" is correct. Here is what the Notepad says:

  Total items scanned: 301818
  - Files & Directories: 298903
  - Registry Entries: 157
  - Processes & Start-up Items: 2547
  - Network & Browser Items: 206
  - Other: 5

How can I fix this problem? Thanks in advance. --Mayfare 16:13, 3 August 2007 (UTC)

Stop using money-expensive, memory-expensive, badly-designed bloatware that can't even compute its results properly after being in active development for more than a decade. Why do you care about a 5 result discrepancy anyway? --froth^t 16:18, 3 August 2007 (UTC)

I was wondering if the 5 result discrepancy would harm my computer. --Mayfare 16:24, 3 August 2007 (UTC)

I noticed that there is actually 5 category, If you ever programmed, you'll know that difference of +1 and -1 are frequent when you write code because of indexes, maybe there was some error in the program interface that count one more item per category. The count in the text file is probably the good one as it was created using the variables and not what was displayed. --PhoenixQc 17:02, 3 August 2007 (UTC)

I suspect it may be quite simple: that in the first case the program is mistakenly adding the "Other" category twice. --Tardis 21:14, 3 August 2007 (UTC)

Can there be another file category other than Files & Directories, Registry Entries, Processes & Start-up Items, Network & Browser Items, and Other that I am unaware of? --Mayfare 15:51, 7 August 2007 (UTC)

vista start menu

Anyone know of any way to automatically go to All Programs when I hit the "start orb"? My frequently used programs and pins are all there in All Programs and I always hit it whether the program I'm looking for is frequently used / pinned or not. --froth^t 16:16, 3 August 2007 (UTC)

Stop using money-expensive, memory-expensive, badly-designed OS that can't even work properly after being in active development for more than a decade. Why do you care about 1 more click anyway? --PhoenixQc 17:17, 3 August 2007 (UTC)

PS. I hope you like those helpful answer.

I for one like vista. It's memory expensive, money expensive and I'll even concede that it's badly designed, but it's much more functional than any other OS I've used (os x, xp, a dozen linux distros) as far as day to day work goes. For programming I wouldn't dream of working in anything but linux but for day to day operations KDE is ugly, sloppy, inconsistent, and provides an incomplete interface to the OS- far too many system-critical settings still rely upon configuration files scattered about the filesystem. Exact same for gnome, but it's paralyzed by minimalism so for even the most basic tasks it's more efficient to use the command line. OS X is just annoying in every way- you can't tell which programs are open, the graphical API is maddeningly inconsistent, there's virtually no program support compared to the staggering amount of code written for windows and linux. Windows (especially vista) is pretty and painstakingly consistent with its graphical API. It has its endless idiosyncrocies but after using it as my main OS for my whole life it's been mastered, and with my knowledge I'm more efficient with most tasks than anything but the most hardened bash jockey. Command line switches and file type handlers can perform spectacular stunts, and basically every stupid DRM or licensing restriction on vista has been cracked, so it's functionally (not legally I suppose) similar to free software. And I care about 1 more click because I have to click with no purpose an additional time every time I want to open a program, it's inefficient! --froth^t 00:45, 4 August 2007 (UTC)

Here.. someone could like Norton AV for all of the same reason you exposed... You noticed my answer was related to one of your answer and that I was sarcastic didnt you ? --PhoenixQc 14:40, 7 August 2007 (UTC)

One of my clients had a problem in Windows XP that may be what you want. She had a weird icon in her quick-launch bar. When she clicked on it, it opened up the "All Programs" dialog. I deleted it because she thought it was weird. I believe she clicked on "Start" then drug the "All Programs" entry to the quick start bar. This made a shortcut icon on the quick start bar to launch the "All Programs" window. If that works in Vista, you'll have two buttons (Start and the new icon). Clicking the new icon will take you right to the programs menu you want. Of course, I can't test it. I haven't had Windows on any of my computers since 1998. -- Kainaw^(what?) 17:44, 3 August 2007 (UTC)

Nope, it doesn't work in vista. --froth^t 00:32, 4 August 2007 (UTC)

You might consider using a keyboard macro program like AutoHotkey to make various unused Win+letter combinations launch your most commonly used applications. It's much faster than opening the Start menu, even if it did go straight to All Programs. -- BenRG 21:30, 3 August 2007 (UTC)

Moving to object-orientated languages from GWBASIC

Yes, I know its old, but the only computer language I am fluent in is GWBASIC. I dont know anything about object orientation, its a rather alien concept to me. So what would be the easiest way to learn it? Are there for example any toy educational languages I could play with for a while? (There is a page listing these somewhere in Wikipedia). People keep recommending Python - although this may not be entirely OO - , that would be the next language I would like to learn. However I can only snatch ten minutes every day or two to spend on learning it. Thanks 80.2.221.69 19:24, 3 August 2007 (UTC)

I learnt OO using Smalltalk - and found it very easy to pick up the concepts. --Worm 22:40, 3 August 2007 (UTC)

Why don't you learn some OO concepts from a book or some online texts first? OO is not solely about programming, but how you structure your code and how you model relationships.

I have already tried reading an introduction to OO but did not have enough time to concentrate on it. Want something that breaks it down into 5-minute chunks. Plus reading about it is not very effective compared with doing something. 80.2.194.185 14:46, 4 August 2007 (UTC)

Just pick up any book on C++ and especially if it was written in the early days of the language it'll go out of its way to contrast with C.. which is basically the object oriented portion. But my personal summary is that if you're going from top-down to OO, you're losing a ton of neat hacks and a lot of the fun of programming, as well as any semblance whatsoever of efficiency. With OO you have clearer code for others to read, and certain problems are easier to model in OO. Also it's a bit easier to jump into an object-oriented languange since chances are a lot of the common routines have pre made objects --froth^t 15:30, 4 August 2007 (UTC)

Personally if you are comfortable with BASIC, I would recommend you jump to a BASIC-based language with OO-like functionality, as it will be a lot easier than jumping into a totally different language (C++ is going to be totally alien to someone who learned programming with BASIC, it is a totally different approach). RealBasic uses BASIC syntax but is OO in its handling of controls and things of that nature; it might be a nice way in. --24.147.86.187 17:14, 4 August 2007 (UTC)

The concepts I learned from ZZT, although I never got around to (re)learning them in an official language. 68.39.174.238 14:59, 7 August 2007 (UTC)

You could try Visual basic. I found it very easy to learn. Lmc169 14:43, 9 August 2007 (UTC)

CDDL / GPL license question

Hi, I am developing a software under the GPL, and I wish to use a library that is licensed under the Common Development and Distribution License.

1. Can I do this?
2. Can I distribute the CDDL library with my software?

I am confused by a statement here that says "a module covered by the GPL and a module covered by the CDDL cannot legally be linked together."

Thank you very much. --131.215.159.28 20:58, 3 August 2007 (UTC)

The problem is that the GPL is "viral": Anything linked to GPL'd software is required to be GPL'd. Since the CDDL is incompatible with the GPL, you can't use the CDDL library. A lot of people mindlessly apply the GPL to their software, not considering the consequences of doing so. If this is your own program, and you wish to use the CDDL library, your options are to have it in a separate executable and use inter-process communication of some sort to access the functions of that library, or release your software under a less restrictive license than the GPL. Donald Hosek 22:41, 3 August 2007 (UTC)

Actually, it's simpler than that; since it's you who have the copyright to the GPL part, just add a variant of the OpenSSL exception. --cesarb 13:01, 4 August 2007 (UTC)