Wikipedia:Reference desk/Archives/Computing/2008 January 20

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January 20

Blocking Texts

I have tried to talk to a customer service rep for this problem, but unfortunately I can't understand those from India that well. SO... I'm going to ask it here and maybe get a more easy to understand response. Someone, for the past 8 months, has been texting my phone "PLEASE CALL". I have called them and told them to stop but they outright refuse that they are the right person. The phone I have is this one. How can I block their texts? I really need to know. Thanks, 76.196.0.96 (talk) 01:34, 20 January 2008 (UTC)

Unfortunately, I think you'll have to contact your cell phone provider to handle this. Do they have a storefront location where you could speak face-to-face with someone? They may be able to help. Otherwise, I'd say to attempt to escalate the call to a manager or higher level tech support person, and hope that you get someone with whom you can speak. Best, UltraExactZZ ^Claims ~ Evidence 14:58, 21 January 2008 (UTC)

wireless monitor

Is there any monitor that conects wirelessly with the computer? (like keyboards, mouses do).217.168.1.14 (talk) 02:03, 20 January 2008 (UTC)

I know there is a USB monitor. Kushal^t 15:07, 20 January 2008 (UTC)

Displaying a 1024*768 image at a 24-bit color depth and refresh rate of 50Hz requires a transfer rate of 1Gbit/s. Articles like Wireless USB mention transfer rates of up to 500Mbit/s. So it looks like it will be a while before it would even make sense to make a wireless monitor. -- Meni Rosenfeld (talk) 15:31, 20 January 2008 (UTC)

I was talking about a wired usb connection ... and that in itself is something new to me. Kushal^t 20:03, 20 January 2008 (UTC)

This is clear to me - I was responding to the OP. I gave "Wireless USB" as an example only because it seemed to be the best relevant match. -- Meni Rosenfeld (talk) 20:08, 20 January 2008 (UTC)

I am just curious. How did you come up with 1 GBit per second? Kushal^t 00:14, 21 January 2008 (UTC)

1024*768*24*50 Trieste (talk) 02:10, 21 January 2008 (UTC)

Yep. Of course, this analysis comes with a few reservations:

1. I rounded the result.
2. I have assumed that every bit of information actually needs to be sent. If we compress the image (perhaps in a lossy way) before sending it and have the monitor uncompress it, we may be able to reduce this but I think it will be too heavy for the monitor.
3. I have only given the information-theoretical lower bound. We may actually need much higher transfer rates due to technical reasons.

-- Meni Rosenfeld (talk) 09:41, 21 January 2008 (UTC)

This makes me scratch my head - check this out - while reading my response to your post, basically almost nothing moves on your screen - normally, right? - so maybe an algorithm could be figured out only to transfer information on relevant changing pixels, without having the need to send the Wikipedia logo umpty times per second. You'd kinda need a decoder (a hardware one, maybe?) on the receiving end to manage this. Then the required bandwidth goes down by one or two orders of magnitude. Of course, for videogames or movies it's exactly the opposite. What do you think? --Ouro (blah blah) 11:24, 21 January 2008 (UTC)

Update: what if a part of the subsystem responsible for generating graphics was in the monitor - I'm wondering whether the bandwidth requirement could still be reduced due to part of the image being text, which can be drawn from information on font, colour, location on screen, and needn't be sent as image. --Ouro (blah blah) 11:29, 21 January 2008 (UTC)

Sounds like you're inventing the wireless X terminal! --tcsetattr (talk / contribs) 11:35, 21 January 2008 (UTC)

Hmmm... kinda, maybe. Is this plausible, what I wrote? Seems sound to me. --Ouro (blah blah) 11:41, 21 January 2008 (UTC)

Its totally plausible to me. I mean the sky may be the only limit in the technology but boy what a great limit it is! We have just a fixed spectrum to broadcast in and anything that helps squeeze and cut down the bits needed to be wirelessly transferred is a potential money making machine. Yes, text could be separately sent and so could stationery images ...

With today's technology, I would not play games on wireless monitor due to the enormous potential lag. So, the only remaining thing is watching videos ... maybe you could figure out some deal with Apple, Inc. for its Apple TV patents. lol Kushal^t 12:46, 21 January 2008 (UTC)

Horror of horrors: I am not a lawyer and this is not legal advise. If it was not clear to the reader, let me clarify that the above post is about a hypothetical situation and does not create an attorney-client relation. (Lest I get banned from the Wiki world). Kushal^t 12:49, 21 January 2008 (UTC)

For games, movies and graphic-intensive stuff that does not need top quality, the graphics could be compressed (lossly, heck, MPEG?) so they fit. Do we need to patent this somewhere? :) --Ouro (blah blah) 12:53, 21 January 2008 (UTC)

Of course, it should all be possible, the only questions are the cost, the quality, the compatibility issues and the overall complexity. I don't think that with our current technology, any of this is justified for solving the relatively marginal problem of a cord between the computer and the monitor. In any case the problem with wires is when there're too many of them - if you eliminate them from the mouse, keyboard and (if possible) printer and speakers, having the power and monitor cables left isn't really a big deal (I'd love to see wireless power, though). -- Meni Rosenfeld (talk) 16:09, 21 January 2008 (UTC)

They're already dabbling in that, though. I was kinda freaked out when I read that report on wireless electricity transfer by means of two resonating items-that-I-forgot-designations-for, last year there was something like this, not? --Ouro (blah blah) 17:11, 21 January 2008 (UTC)

Correct me if I'm wrong, but haven't people been transmitting FULL SCREEN video images at FULL FRAME RATE for decades? Duomillia (talk) 23:41, 25 January 2008 (UTC)

EVE subscriptions

I am interested in the game EVE Online, though I am unable to pay for a subscription, due to me being a student. I know there is an option of paying for the subscription using ingame currency, and I am wondering how much time I would have to invest to be able to afford paying that way. How much virtual currency does the subscription cost? Being that I can't play for huge amounts of time during the week, would I be able to generate enough income to pull this off? —Akrabbim^talk 03:40, 20 January 2008 (UTC)

If I remember correctly from the short time I played (before I left due to skepticism regarding the developers' integrity), the exchange rate was around 10M isk for the equivalent of 1$. When you're just starting out you should be able to gain about 1M isk, the equivalent of 10 cents, per hour. This is really bad. Also, if you use all your in-game currency to pay for the subscription, you won't have any left to buy in-game stuff. Of course, if you've been playing for 5 years and you're the CEO of a mega-corporation you might be able to make more isk, but in your situation this is not really an option. If you are unable to work IRL to raise the necessary cash, you should forget about the game for now. -- Meni Rosenfeld (talk) 10:01, 20 January 2008 (UTC)

Localhost

According to my security history, there was an intrusion attempt on my computer by localhost (127.0.0.1). I've already figured out what localhost is, but what does an intrusion attempt by it mean? 69.40.255.101 (talk) 04:09, 20 January 2008 (UTC)

If you own computer is trying to intrude into your own computer... you can probably ignore it. 127.0.0.1 is your own computer. --wj32 ^t/c 05:22, 20 January 2008 (UTC)

I know that Google desktop uses this loop. Kushal^t 14:42, 20 January 2008 (UTC)

What software recorded this log? Kushal^t 19:53, 20 January 2008 (UTC)

I have Google desktop installed, so it might have something to do with that. —Preceding unsigned comment added by 69.40.255.101 (talk) 00:16, 21 January 2008 (UTC)

Password for folder

How is it possible to set a password on a folder or file, using Vista? --ChokinBako (talk) 05:31, 20 January 2008 (UTC)

Vista Ultimate will do it, as I think will the Enterprise version. Apparently, you right click on the file or folder, click the Advanced button, and check off 'Encrypt Contents'. Otherwise, you may want to look at TrueCrypt. -- Consumed Crustacean (talk) 07:13, 20 January 2008 (UTC)

I haven't used Vista, but I think you're talking about NTFS encryption, which has been around since Windows 2000. I don't recommend using it unless you know what you're doing, since it has a lot of gotchas (detailed in the article). You're probably better off with TrueCrypt, which has a much simpler security model. -- BenRG (talk) 12:11, 20 January 2008 (UTC)

He didn't outright ask for 'encryption', so I assumed the level of security wasn't a huge concern. If it is, I'd always take TrueCrypt for sure. -- Consumed Crustacean (talk) 05:17, 21 January 2008 (UTC)

According to the lead in the above article, it appears that EFS is supported in all versions of MS Windows Vista. Can anyone confirm that? Kushal^t 14:33, 20 January 2008 (UTC)

No, it is only available in Enterprise, Business and Ultimate editions, not Basic or Home Premium. [1] dbfirs 17:37, 20 January 2008 (UTC)

Thank you. I see the article has been updated to reflect this as well. Thank you once again. Kushal^t 19:52, 20 January 2008 (UTC)

Uh NTFS encrpytion unlocks everything at mount, you can't "set a password on a filder or file" --f f r o t h 04:48, 23 January 2008 (UTC)

flow chart

i wud like to have a help about how would a flow chart for payment of telephone bill would be like. my requirement is to develope a flow chart which wud help in studying a software developed to build a automatic bill payment of telephone. it will b for d company n what possible sections will be there its on you guys.. PLEASE HELP ME OUT ............ ITS URGENT!!!!!!!!! its my project

thank u —Preceding unsigned comment added by Aadish (talk • contribs) 08:14, 20 January 2008 (UTC)

Languages to learn to get a job as a programmer

I am a electrical/electronics engineer with basic knowledge about computers. I want to take a job as a Computer engineer and I like to become a programmer. What are the languages I should learn to become a programmer? And what are the recommended text books on computer science and programming languages I should learn? (I don't want the name and author of text books but the name of the topics/subjects I should learn)-Thanks.

I assume you mean programming languages. It doesn't really matter what languages you learn because once you learn one well, the differences between languages end up being relatively small. That being said, C++ is probably your best bet if you want to be a professional programmer. If you learned that fairly well (which will take some time—it's not easy!), you'd have no problem transitioning to all sorts of other languages that might be needed (like Java or scripting languages like VB.NET or PHP). As for text books, if you are just beginning programming, the Art of Computing Programming volumes by Don Knuth are classic ways to begin thinking about programming though are not written for any particular language (they are very easy to follow and very readable—they're wonderful). Programming itself is learning how to think through code; the exact language you use only matters in so much as the particular implementation you are trying to enact. --24.147.69.31 (talk) 17:11, 20 January 2008 (UTC)

Since when is VB.NET a scripting language? -- Meni Rosenfeld (talk) 18:18, 20 January 2008 (UTC)

Well, I consider it closer to a scripting language than most. Anyway, it's a lot easier than C++, which was my only point. --24.147.69.31 (talk) 22:12, 20 January 2008 (UTC)

It depends on the market you are aiming at. C and C++ will always be a good start for learning, as they are the base for newer object-oriented languages like Java and C#, and scripting languages like Perl, PHP and Python. Learning C virtually opens the full programming environment. However, you won't find many jobs as C or C++ programmer, mostly because companies are porting everything to framework-based languages like VB.NET and Java. For working, the best options are Java plus some framework knowledge like Apache Struts, or VB.NET. Don't waste your time with C#, for every job asking it there are six or seven asking for Java programmers. As for books, Core Java is a pretty good one, I used it for learning Java. For C, there are some classic books, but most times you can learn it well enough with web tutorials. -- ReyBrujo (talk) 18:38, 20 January 2008 (UTC)

Please bear in mind that C and C++ are two very different beasts. For learning C, the Kernighan/Ritchie book (cover shown in the article) is a must IMHO. For learning C++, get some books on object-oriented design, and focus on the C++ standard library. Avoid explicit dynamic allocation in C++, except in constructors or well-behaved member functions. Remember that, in C++, resource acquisition is initialization. Following that advice will help you stay clear of the zillions of memory-leakage problems that riddle C code. And learn how to program exception-safely. The Exceptional C++ books by Herb Sutter are good in that respect. --NorwegianBlue ^talk 22:29, 21 January 2008 (UTC)

Learn C++ to understand mainstream object orientation; learn Lisp to understand dynamic typing, multiple dispatch, generic functions, and automatic storage management; learn Prolog to understand logic programming; and learn Haskell to understand functional programming and lazy evaluation. Once you know those four you will find it straightforward to pick up any other language. Gdr 20:22, 20 January 2008 (UTC)

If you're a EE with only basic knowledge about computers, it's going to be a lot of work to make CpE.. --f f r o t h 04:47, 23 January 2008 (UTC)

Determining a microprocessor instruction set

Howdy, does anyone know the general procedure for determining a PC's processor instruction set (x86 or AMD64, for instance). Chances are this would be for someone running windows. I can reasonably make educated guesses based on the age of the computer, but is there a way to know for sure? Thanks, --TeaDrinker (talk) 20:17, 20 January 2008 (UTC)

CPUID. Especially the programs listed under CPUID#External links --tcsetattr (talk / contribs) 21:50, 20 January 2008 (UTC)

Outstanding! Thanks, that is exactly what I needed! --TeaDrinker (talk) 18:03, 21 January 2008 (UTC)

C++ struct

What's wrong with the following (besides lacking such advanced ideals as encapsulation)? It seems no different from the basic examples I see in tutorials, but won't compile in Bloodshed Dev-C++ ("expected constructor, destructor, or type conversion before '.' token").

 #include <cstdlib>

 #define         CT_UNTAPPEDLAND         0x0001;
 #define         CF_GREENMANA            0x00000001;

 struct Card //a card in the deck or hand, or a creature in play
 {
       public:
              char name[];
              int power;
              int toughness;
              int dirdamage;
              unsigned long flags;
              unsigned int type;
              unsigned int redcost;
              unsigned int greencost;
              unsigned int flexcost;
              unsigned int damagetaken;
              bool tapped;
              unsigned int fertiles; // used for lands that have Fertile Ground attached
 };

 Card c_for;
 c_for.name = "Forest";
 c_for.type = CT_UNTAPPEDLAND;
 c_for.flags = CF_GREENMANA;

NB: If I move the initialization of c_for inside main(), the error messages are different, though they make equally little sense to me.

Also, what would be the standard way to give the properties default values? NeonMerlin 20:33, 20 January 2008 (UTC)

Your code has to be in a main, because those are executabe lines of code that do stuff, not just initialisers. With that done, you'll get a type error when assigning name[] - change its declaration to char * name; instead and it'll work (but be aware that you're doing pointer assignment not strcpy). If each Card has to have a mutable name (which I guess is what you really want) then you need to tell the compiler how big to make the name field (e.g. char [20] - structs have a fixed layout defined when the type is compiled) and strcpy the data in there. Oh, and you shouldn't have those semicolons in the #define lines.-- Finlay McWalter | Talk 21:03, 20 January 2008 (UTC)

As to initialisers, with name as char name[20];, the initialiser could be Card c_for = {"Forest", 20, 10, 3, 0xff003322L, 4, 0,0,0,0,true,0}; -- Finlay McWalter | Talk 21:09, 20 January 2008 (UTC)

If that fixed size for name makes you uncomfortable then declare name as char * name and to give it content you need to manually malloc() storage for it and then strcpy the data in yourself. Of course this in turn means you have to remember to free that data when you dispose of an instance of Card, and it's keeping tabs of internal details like this (and not burdening the caller with maintaining and tidying up these internal stuff) that methods, constructors, and destructors are for. -- Finlay McWalter | Talk 21:29, 20 January 2008 (UTC)

Or you can change char name[20] with [i]string name[/i], and then assign it the way you are assigning it. The string class has the kind of constructors you need. Regardless of that, they must be inside the main function or some other function, you cannot initialize outside function unless you are declaring and defining the variable in the same sentence (as Finlay McWalter did. -- ReyBrujo (talk) 01:38, 21 January 2008 (UTC)

Batch zipping of .txt files in a folder

I have a folder with lots of text files, but lots of other files of different types. Is there any (free) software available that can zip each individual text file, from something.txt to something.zip, but leave the other files alone? Ideally it would also delete the text files after making their zipped copies. I have Windows. Thanks. 80.0.110.97 (talk) 23:25, 20 January 2008 (UTC)

Can't you just add them using WinZip or Winrar or 7zip and view by file type when you're adding them? Otherwise you can do it the commandline way of something like zip *.txt (depends on what programme you use). --antilived^{T | C | G} 03:04, 21 January 2008 (UTC)

Assuming you're using cmd.exe and Info-ZIP's zip utility, the following command line will compress each txt file in the current directory into an individual zip file with the same base name and then (if the compression succeeds) delete the original txt file:

for %i in (*.txt) do zip -m "%~ni.zip" "%i"

You might want to add other flags after -m (like -9 -X). You might also consider using gzip instead, since it's designed for this kind of file-by-file compression and uses the same compression algorithm as zip (though an incompatible file format). -- BenRG (talk) 09:46, 21 January 2008 (UTC)

Thanks. I have little technical knowledge, how do I actually implement all that in practice please? I belive I have command.com rather than cmd.exe. So do I type something like infozip.exe %i in (*.txt) do zip -m "%~ni.zip" "%i" in the Run slot, afterdownloading and installing infozip? Thanks 80.2.192.252 (talk) 23:45, 24 January 2008 (UTC)