Wikipedia:Reference desk/Archives/Computing/2009 May 26

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May 26[edit]

torbrowser download[edit]

hi, i'm posting from a country that censors its internet access. I was wondering if someone would be able to help me download the tor browser bundle installer from [1] and then post it to something like Thanks in advance, the help is much appreciated. Asdflkjasdflkjasdflkjasdfl (talk) 02:07, 26 May 2009 (UTC)

Here you go. If you need the PGP signature, it's:

Matt Eason (Talk &#149; Contribs) 02:18, 26 May 2009 (UTC)

text file to windows command prompt[edit]

Here's something I can't work out how to do: Suppose I have a simple text file eg


cd/ (newline)
dir (newline)


In the command prompt on windows (cmd.exe) I would like to "execute" (eg MagicCommand Texfile.txt )that text file so that it performs the equivalent of typing cd/ and dir... Is there a way.? (talk) 00:31, 26 May 2009 (UTC)

Rename the txt file so it ends with ".bat". Now you can run it like it is a program. APL (talk) 01:09, 26 May 2009 (UTC)
Ouch - I accidentally typed cd\ instead of cd/ - and typed filename.bat into the command prompt - the computer made (literally) a beeping screeching sound, the screen flashed, and then went back to normal. Tried it again and it didn't.
Can you explain why it went crazy ?
Other than that - thanks - it totally did the trick - (for some reason the thing I'm using will let me create files, and execute them with a "sys insert string here" command, but ignores other requests, despite the documentation seeming to say that it executes windows commands, luckily I can create the bat file and execute it to get round this.
Thank you very much 5* (talk) 03:43, 26 May 2009 (UTC)

UAT test cases for IVR[edit]

Cany any one please tell some UAT test cases for testing IVR system. —Preceding unsigned comment added by Itsmeanil6 (talkcontribs) 07:09, 26 May 2009 (UTC)

I work with IVR systems all day long, and you might as well ask "How long is a piece of string?" What is the purpose of the system? What do the users want the system to do? By definition, UAT is User Acceptance Testing, so the users are the ones who have to decide what makes the system acceptable. --LarryMac | Talk 23:39, 26 May 2009 (UTC)

.NET Exception disassembly[edit]

I don't distribute the PDB debugging symbols with my .NET program, and it's very hard to tell where (on which line) a particular exception occurred in bug reports. Is there a way to show a disassembly or something instead of the useless stack traces .NET gives me? (Hint: I don't think it's even possible to get the address of the instruction that threw the exception...) --wj32 t/c 10:34, 26 May 2009 (UTC)

Accesskeys in Chrome 2.0[edit]

I just upgraded Google Chrome to the new version 2.0, and was extremely disappointed when I realized that accesskeys (e.g. Alt+F, Alt+Z, Alt+L, Alt+R, and so on on Wikipedia) no longer works. Is this on purpose? Can you make them work again in Chrome, or do I have to switch to Firefox? --Andreas Rejbrand (talk) 12:02, 26 May 2009 (UTC)

As I recall, the use of access keys in HTML and CSS was not accepted as a standard because it introduced conflicts with some accessibility tools. Our article, Access key, states that W3C has deprecated access keys as a standard technology. Firefox is compliant for backwards-compatibility reasons with its browser audience, but is technically not in compliance with the standard (Ironically, this is the sort of insult lobbed against many proprietary browsers and technologies - keeping around old and outdated nonstandard technology - just because people like it!) Nimur (talk) 14:05, 26 May 2009 (UTC)
True, but people should still have an option to enable access keys. --wj32 t/c 07:44, 27 May 2009 (UTC)

Building a game Finding headers using for id Tech 2 id Tech 3 engine[edit]

Alright, i want to build a simple game using the id Tech 2 engine (which runs Quake 2) but i have no idea where to start. Any help (like what i need to make) would be appreciated.

PS Yes, i know about all the other engines out there like IrrLicht and OGRE but i want to use id Tech 2 despite the crap graphics quality. so DONT suggest them to me please.  Buffered Input Output 12:50, 26 May 2009 (UTC)

Start with a Quake 2 map editor. That will allow you to create the world for your game. Of course, you will fill it with Quake 2 creatures and items for now. Once that works, you need to get a Quake 2 object editor to alter the Quake 2 creatures and objects for your game. Then, place the new objects in your world. Then, create custom sounds to replace the Quake 2 sounds. Step by step, replace the Quake 2 game with your game. That is a starting point. As for "which" Quake 2 editor - it is up to you. Some are simple to use but limit what you can do. Others are very complicated, but allow you to do a lot of weird things. -- kainaw 12:55, 26 May 2009 (UTC)
Kainaw's excellent reply, above, details the fundamental approach - incremental changes based on the original game and its assets. The trouble is that a game even of Quake2's age represents man-years of work producing all the assets; so you either have to replace stuff incrementally (which means your game will look very Quake2-ish for a long time) or take the drastic step of gutting all the game logic and assets, which means you're a long way from getting anything going (and in great danger of becoming disheartened and quitting). Now the order of the tasks Kainaw describes is more flexible; it depends on your interests, and skillset, and what you're hoping to achieve. As a programmer, if it were me, I'd leave the assets (maps, textures, character meshes and skins, sounds) well alone, and produce a different game with the same assets. On a basic game like Quake2 the game logic is incredibly simple, so even a very basic change can make for a different game. You'll pretty soon need to resort to the level editor, but only to manipulate entities (the descriptors which position objects and help them function in the game world). I'd bet with no more than a couple of dozen lines of code and adding a bunch of entities to a deathmatch map you could create a novel custom game (e.g. "Strogg Wars", where the map is filled with two ever-replenished armies of opposing Strogg battling each other and ignoring the player, and the player has to collect the heads of dead Strogg Tanks without getting accidentally blown up). Personally I think too many mods (and I suspect more than a few professional game development studios) start with (and over emphasise) the graphical assets and leave the game itself too late, and run out of steam under the weight of the work needed to produce assets of worthwhile quality. The nice thing about "code first" is that you get a new-ish, worthwhile game almost immediately (and you can tell, crucially, if what you're doing is fun as soon as possible). On the other hand if you start to create Pixie Apocalypse by designing ten new meshes for different kinds of pixie, you'll put in hundreds of hours of work and end up only with an intermediate product that replaces one kind of Quake 2 Strogg with a pixie that behaves just like a Strogg. (talk) 17:45, 26 May 2009 (UTC)
One practical problem you may have is building Quake2; the id Software original sources depend on tools, headers, and libraries from a decade ago, and you may run into real difficulties in assembling what it needs, and then getting it to build. The linux version of Q2, for example, seems to depend on a bunch of libraries that aren't maintained any more, so porting it to a modern setting is a bunch of work. For that reason it's probably smarter to start with a Quake-tech derived platform like DarkPlaces or ioquake3, because they're still in active development, and so build with current tools and run on current OS distributions. ioQuake3 in particular seems to already be the ancestor of a number of free games - (talk) 18:30, 26 May 2009 (UTC)

Screw id Tech 2, i just found out that id Tech 3 is also GPLd and I downloaded that instead. BUT...i don't have the MFC headers and stuff that i think i need to compile it. Where can i get the MFC headers? PS I am using Visual C++ 2008 Express. Any more help? (Sorry for wasting your time, guys...)  Buffered Input Output 11:30, 27 May 2009 (UTC)

You might consider checking out ioquake3. It's a "cleaned up" version of the Id Tech 3 engine. It's probably easier to get working. APL (talk) 14:46, 27 May 2009 (UTC)

Strange 2D "barcode"[edit]

So I typed to my browser, and instead of Microsoft Virtual PC (please no VMware/VirtualBox suggestions) I got this picture: (link). It has a 2D "barcode" in the bottom left corner. How do I decode it? (Just out of interest.) --grawity 16:44, 26 May 2009 (UTC)

See High Capacity Color Barcode. Nanonic (talk) 17:17, 26 May 2009 (UTC)
That site is nothing to do with Microsoft and for their Virtual PC software you need to go here. ZX81 talk 17:22, 26 May 2009 (UTC)
That I know, but thanks anyway. --grawity 19:11, 27 May 2009 (UTC)

google desktop and yahoo widget[edit]

can you compare? what are the pros and cons of each? which one makes the computer run slower? —Preceding unsigned comment added by (talk) 17:50, 26 May 2009 (UTC)

Since computers vary, it's hard to form an opinion. The only thing you can do is try both and determine which runs slower on your computer and use the faster one.  Buffered Input Output 11:31, 27 May 2009 (UTC)

VLC transcode settings for iPod/AppleTV compatible MP4?[edit]

If I want to convert some FLVs to iPod compatible .MP4s, what video bitrate do I need to use for h264 video? -- (talk) 20:16, 26 May 2009 (UTC)

Many bit rates will work. I have found that around 900 kbps is suitable for the video, and I prefer to encode my audio as an MP3, ranging between 64 kbps to 192kbps for music-videos and others where I want to preserve high fidelity audio. These settings produce a video which has no noticeable artifacts on an iPod Nano's tiny screen. Depending on your device and your preferences, you can boost or decrease the video bit rate. I have seen video with as low as 300 kbps which is "suitable" for viewing. Nimur (talk) 20:34, 26 May 2009 (UTC)
What's the maximum bitrate for iPod? for AppleTV? -- (talk) 22:27, 26 May 2009 (UTC)
This enthusiast website claims 768 kbps for x264 and 2500 kbps for MPEG-4 are the absolute maximum bit rates for iPod video, but I'm pretty sure I've got two or three exceptions to that currently loaded on my Nano. Numerous other forums seem to concur that these values are not actually hard upper-limits. My high-bitrate videos play fine. Perhaps they are being decoded at a lower bit-rate, although I am not sure if Scalable Video Coding is in use to select a sub-set of the full video file at a lower bit-rate (I don't believe the iPod implements this feature of either compression method). Nimur (talk) 23:56, 26 May 2009 (UTC)
Is such a high bitrate useful? I use 800kbps for video on my Nokia 5800 which has more than double the resolution the Nano has, and I find it perfectly acceptable. --antilivedT | C | G 06:11, 27 May 2009 (UTC)
I could probably reduce the resolution without any significant quality loss. I don't like artifacts and I'm barely at 25% of full capacity, though, so there's no immediate need for more compression. Nimur (talk) 13:23, 27 May 2009 (UTC)
You might want to consider HandBrake, which has built-in profiles for iPod videos and AppleTV. chocolateboy (talk) 09:24, 28 May 2009 (UTC)
I have not been able to get Handbrake to accept FLVs to transcode. -- (talk) 03:59, 29 May 2009 (UTC)

Technically, *transcode* is the key word here. Most FLVs are already h264 movies, I just need to unwrap it out of FLV and put it into a generic M4V/MP4 file. I really don't want to re-compress it. -- (talk) 04:00, 29 May 2009 (UTC)

Have you tried ffmpeg?
ffmpeg -acodec copy -vcodec copy -i input.flv output.mp4
chocolateboy (talk) 08:09, 29 May 2009 (UTC)

That's sound pretty cool. But here's the error I got:

 Duration: 00:01:09.7, bitrate: N/A
 Stream #0.0, 29.97 fps(r): Video: 0x0004
 Stream #0.1: Audio: mp3, 44100 Hz, stereo

Output #0, mp4, to 'forza.mp4':

 Stream #0.0, 1000.00 fps(c): Video: 0x0004, q=2-31
 Stream #0.1: Audio: mp3, 44100 Hz, stereo

Stream mapping:

 Stream #0.0 -> #0.0
 Stream #0.1 -> #0.1

[mp4 @ 0x5597b8]dimensions not set Could not write header for output file #0 (incorrect codec parameters ?) Any ideas? -- (talk) 15:38, 2 June 2009 (UTC)

WAP Question[edit]

Dear Sir/Madam I would like to hear your opinion on this matter: One of the disadvantages of WAP is that content available for PDA`s is in text format only and also , no email attachment support exist for WAP technology, transmission rate is slower than a typical 56 Kbps modem and web designer do not take time to implement WML on their pages. I am wondering wether or not any of this statements are true.

Kind Regards.

Antonio Solinas —Preceding unsigned comment added by (talk) 22:28, 26 May 2009 (UTC)

I have moved your question to a new section to keep the responses separate from above questions, and formatted it properly. Nimur (talk) 22:30, 26 May 2009 (UTC)
I think you have many misconceptions. First of all, WAP often refers to any wireless access point, including 802.11 access. I think you mean Wireless Application Protocol, is this correct? Maybe you should check that article out. More commonly, mobile devices are supporting full-fledged HTML and web applications, so it is not clear whether the future will hold a place for specialized technologies like Wireless Markup Language, especially as mobile device capabilities continue to increase at an accelerating rate. Nimur (talk) 22:35, 26 May 2009 (UTC)

Amount of vi and/or emacs users[edit]

Are there any estimates on that? My guess would be from 5 thousand to 5 billion and it makes me feel a bit ignorant. -- (talk) 23:23, 26 May 2009 (UTC)

Uh, 5 billion? The world population is 6 billion and 5 out of 6 people are certainly not using any computers at all, much less those particularly geek-friendly programs. My guess is more like 1 to 10 million at most. -- (talk) 23:30, 26 May 2009 (UTC)
It's estimated that Linux boxes are about 5% of the personal computers in the world (it's really hard to know for sure) - since there are about a billion personal computers in use around the world, there are probably around 50 million Linux boxes - plus some other UNIX/BSD varients. While other OS's can run both VI and EMACS - it's really rare to see a Windows user using either of those editors. So I think the upper limit is 50 million - but it's gotta be way less than that. Firstly, vi and emacs are really programmer tools - they're really user-hostile for the layperson. I would be surprised if there were more than 10 million serious programmer types out there using one or the other - and the split (in my experience) is close to 50/50. So if forced to make a guess - I'd say about 5 million each...bit the true answer could easily be 10x more or 10x less. SteveBaker (talk) 23:44, 26 May 2009 (UTC)
vi is a forced skill. Those who swear by it usually don't know there are a million easier ways to do the same thing in a proper user-friendly editor. vi was created during the same time unix was invented, when everyone was high on LSD and not thinking straight... ok just kidding, don't slam me for being un-encyclopedic! My guesstimate would be a few million hardcore C/unix type masochistic specialists who hate GUI operating systems. Sandman30s (talk)
I suppose vim is just about usable, no, aargh, go away, I don't want to see any of these editors anytime ever ever again. I hate them and started using something anything better as soon as I could. They really are for text oriented people and I'm more visually oriented. And did i mention I hate them? I doubt there really could be even one million people who use them often. I'm sure it must be possible to estimate the numbers, anyone new would be asking questions about perplexing behaviour or complaining about them or wanting changes so the usage of a forum might indicate the numbers. Dmcq (talk) 10:05, 27 May 2009 (UTC)
The OP did ask the number of users, not experts. I, for one, am forced to use vi because I'm an Oracle specialist who has to work on unix systems and most of the time, there is no alternative. I would imagine there are a large number of IT systems running on unix and the support specialists would be forced to use vi etc. So a few million would be reasonable, given that there is a large number of IT staff and unix enthusiasts worldwide. Sandman30s (talk) 10:55, 27 May 2009 (UTC)
I use vi on both Linux and Windows; actually I use Elvis on Windows. Why do I not use Notepad you ask? Simple! I can drive vi without thinking and when I'm programing in Perl, I automatically drop into vi mode. I am constantly erasing the vi commands that I enter while using Notepad. One thing for sure, after 20 years of using vi, I'm still no expert. Sometimes, colleagues will try and show me a "better" way to do something in vi. Like I said earlier, I can drive vi without thinking. If I thought about what I was doing, I could probably use all manner of advanced techniques. However, if I did that, I wouldn't have enough spare brain power to think about the pretty girl who sits across the room. -- (talk) 22:37, 27 May 2009 (UTC)
I've used vi (now vim) since about 1976. So I suppose I'd better take a shot at defending it. There is no other editor on the planet that runs on so many different systems and has been constantly available that entire time. If you only intend to spend your time on Windows - you probably shouldn't bother. But if (as I do) you switch between Linux and Windows - and have had to work on Irix and Solaris and half a dozen different Mac OS's - the ability to edit files without having to think which of them you are using - without EVER having to learn another editor has huge value. I had vi working on my AtariST and my Amiga. No matter what editor you use - there will come a time when you have to switch to something else because your preferred editor doesn't exist - and I utterly guarantee that vi or some varient will still be there when that happens.
Sure, I know that emacs is better - but every time I get up the enthusiasm to try to learn it - I get some actual work to do and I fall back to what I know. Furthermore - vim is surprisingly powerful - but it's not for people who reach for the mouse all the time. It's for people who type FAST - who want to bash out a file in the shortest possible time. That means touch typing. Every time you have to move your hand onto the mouse - you wasted two seconds - if you have to reach for the arrow keys or function keys - you've lost a second (and you're setting yourself up for RSI injuries about 30 years into your career!) You probably haven't noticed that all of the vi commands that you use the most are on the home-keys - and none of the common commands need control or alt. We don't use the cursor arrows for moving the cursor (although you can) - it's h,j,k,l - where the four fingers of most people's dominant hand should be resting. On your left home keys you have append, substitute, delete and find (a,s,d,f).
Sure, vi is a tool for command-line users - but that too is the route to becoming a power-user. To pick a crazy example: Quick! Zip up all of the files in the current directory that start with 'a' through 'f' or 'w' and have filenames exactly six characters long that are properly spelled English words...let's say that there are 40 of these files amonst 400 files in that directory. It took me about 4 seconds to do that using the Linux shell (or using Cygwin under Windows). You quite simply can't do that with point/click tools - you can't do it in an hour - you have to manually look through all of the files. As a professional programmer - I'm totally crippled in a world where the only things you can do with a program is what the guy who wrote it thought you might want to be able to do. vi comes from a world of power users who need that kind of speed. Sure - it's not for everyone - but for people who need it - there is no substitute...except perhaps emacs. SteveBaker (talk) 06:18, 28 May 2009 (UTC)
Steve, thanks heaps. I used to like vi (on AIX) enough to get Elvis for Dos, when Windows was a baby and mouses were a new-fangled rarity. Then I got thrown into a Windows world and didn't know there was a version for Windows (but I've downloaded it now, as tomorrow's new toy). It is only for fast touch typists, but it saves reaching for the mouse or looking up from notes. Most Linux users with prior Windows experience would probably be using a GUI, so the count of Unix/Linux boxes in the world would not be very accurate except as the upper limit. I think 5000 would be a bit low, but 1,000,000 would be high.KoolerStill (talk) 21:03, 28 May 2009 (UTC)

I use vi for several reasons. First, it was the first editor I learned to use. Why would I learn emacs or nano when I already know vi? I tried emacs in Windows, and it was pretty hard to learn, too. I also consider myself a minimalist, which is why I use Notepad in Windows as a replacement for Dreamweaver and Visual Studio. It's nice to start an editor and begin typing right away. Further, vi is installed by default in all UNIX-like systems.--95795n (talk) 23:42, 28 May 2009 (UTC)