Wikipedia:Reference desk/Archives/Computing/2007 April 5

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April 5

Starting a job stopped

Is it possible to start a job in 'nix and then immediately stopping it, without me having to enter ^Z once it starts? Please highlight shell-specific assumptions you may make. 00:08, 5 April 2007 (UTC)

Good question! The only way I know of is using a debugger. It would also be possible to write a tiny little "helper" program, that just started a program stopped, in the same way that a debugger does. (But I've never heard of such a program being standard anywhere.) And even this probably wouldn't be exactly what you're looking for, because the "stopped" state that programs-under-a-debugger have is, I think, pretty different from the suspended state that ^Z gives them. —Steve Summit (talk) 00:54, 5 April 2007 (UTC)

IIRC the command "kill" can be used to send arbitrary signals, one of those signals happens to be the same signal that is sent when ^Z is typed. Root⁴(one) 02:02, 5 April 2007 (UTC)

Sure. But starting a process and then killing it with -STOP is only quantitatively (not qualitatively) different than starting it and hitting control-Z. (But it's true, the former can be scripted, so the window during which the process runs could be made considerably smaller.) —Steve Summit (talk) 02:14, 5 April 2007 (UTC)

^Z just sends a SIGSTOP, so starting the process and then immediately sending it a SIGSTOP with kill will be pretty close to what you're looking for. In bash, $! is the PID of the process most recently started in the background. Doing:

yes & kill -stop $!

will start a yes (which normally prints an endless series of the letter "y" to the screen) in the background, and then stop it quickly enough that it doesn't even get the first one out (though that's not guaranteed). --TotoBaggins 02:23, 5 April 2007 (UTC)

I thought of this, but if you put this in a shell script, won't this have a problem? (controlling the jobs started in a child process?) —The preceding unsigned comment was added by 129.78.208.4 (talk) 03:33, 5 April 2007 (UTC).

No. The beauty of interacting with a shell is that you effectively *are* in a shell script, so (almost) everything works the same. What you're trying to do is unusual; maybe you're doing something the hard way. Mind telling us what you're trying to accomplish? --TotoBaggins 11:53, 5 April 2007 (UTC)

No, it doesn't work, I just tested it. The calling shell doesn't know anything about the jobs that the shell process invoked by the script. I have to use ps to interact with jobs that the script backgrounds.

Ideally I want to have a script or failing that an executable that starts a command and then immediately halts it. This is, for example, to queue up some jobs that may cause excess load to a system if run in parallel. I can then monitor with the shell's job control which jobs have finished so I can continue another one. Ideally something like this should be automated, or I can run each job one after the other in a subshell in the background, but I want to know whether it's possible to do this as I've described. —The preceding unsigned comment was added by 58.163.129.56 (talk) 11:30, 6 April 2007 (UTC).

For the record, ^Z sends SIGTSTP, which by default has the same effect as SIGSTOP but is a handlable signal. If you can arrange for the job to attempt to do terminal input (or, in some cases, output) as soon as it starts, you can arrange for it to get SIGTTIN (or SIGTTOU) which can suspend it. If you're writing your own code, you can use ptrace(), in particular the PTRACE_TRACEME option (on Linux; 0 on Solaris, ...) which literally allows you to start a process (really exec() a file) suspended. --Tardis 15:29, 5 April 2007 (UTC)

RTHDCPL.EXE illegal system DLL relocation

I got an error message with the above heading. The message said: "The system DLL user32.dll was relocated in memory. The application will not run properly. The relocation occurred because the DLL C:\WINDOWS\Ststem32\HHCTRL.OCX occupied an address range reserved for Windows system DLLs. The vendor supplying the DLL should be contacted for a new DLL."

What does this mean? What should I do? --Halcatalyst 01:08, 5 April 2007 (UTC)

Download the latest drivers from http://www.realtek.com.tw/ for your Realtek audio device. If is an onboard chip, check with your board manufacturer for drivers. --Kainaw ^(talk) 01:52, 5 April 2007 (UTC)

Thank you! I downloaded the drivers and ran setup.exe. The error message went away and the audio now works fine. --Halcatalyst 03:12, 5 April 2007 (UTC)

You can also apply KB935448, which is the fix for that specific problem. It will fix the problem for all programs, not only the Realtek one. --cesarb 22:24, 5 April 2007 (UTC)

So the problem was caused by a Microsoft update I downloaded. Hunh. I hope there isn't an infinite regress here. :P I'll apply KB935448. Thanks for the tip! --Halcatalyst 03:25, 6 April 2007 (UTC)

my perfect blog

I want to create a blog. My main issue, for what constitutes a perfect blog, is that it create interlinks, at least as easy, as wikipedias double brackets. Are there blog hosts which interlink this easilly? I know of wikilogs, but as for thers editing my page...that is...eh...not so much. Do most or alll blogs fit that requirement, and I don't know about it, yet? Thaddeus Slamp 20:03, 3 April 2007 (UTC).

Try Tiddlywiki. Its a wiki-like page that you can edit, with interlinks, and its all on one html page! Think outside the box 06:17, 5 April 2007 (UTC)

Thank you.Thaddeus Slamp 23:36, 5 April 2007 (UTC)

I should have specified that I must not have to load anything, and this site will not do for that reason. Do you (or does anyone else) have any alternative selections? Thaddeus Slamp 18:56, 10 April 2007 (UTC)

'Virtual' graphics card for openSUSE linux?

Is there a project to emulate a graphics card under openSUSE? I need it to 'pretend' to be a graphics card and put the calculations on the processor. Thanks!--71.195.124.101 02:37, 5 April 2007 (UTC)

I doubt it. Graphics cards are useful because if processors done the calculations graphics cards did, everything would be horribly slow. —The preceding unsigned comment was added by 129.78.208.4 (talk) 05:20, 5 April 2007 (UTC).

I know. I have a core duo 2ghz and no 3d ecaleration. A little help anyone? —The preceding unsigned comment was added by 75.31.163.211 (talk) 05:34, 5 April 2007 (UTC).

Uhhh why on earth do you have a C2D but no 3D acceleration? Is it just that you don't have the correct drivers installed? What is your graphics card? --antilived^{T | C | G} 08:23, 5 April 2007 (UTC)

I added the core 2 to an ancient box I had. —The preceding unsigned comment was added by 75.31.163.211 (talk) 18:09, 5 April 2007 (UTC).

Yeah, it's possible but even with a C2D you're going to find it pretty slow going. What you need is Mesa3D. It's basically a software replacement for OpenGL. It actually gives better standards compliance than many proper driver sets. The link for it is here

Elaverick 23:25, 5 April 2007 (UTC)

Comcast Technician labor

if i wnted to install comcast high speed internet and i already had a modem and an install kit would i still be charged for labor by the technician just because they come and install the stuff for me.--logger 05:41, 5 April 2007 (UTC)

Yes, that's exactly what "labor" means. What you already have is called "parts". StuRat 05:50, 5 April 2007 (UTC)

What would the average labor costs be if anyone knows?--logger 05:54, 5 April 2007 (UTC)

It depends on what you need to have done. If someone just has to come out and turn on a switch, it might be $50-$60, which they often bill as a "setup fee". If they have to do wiring and cable drops in your hours, it could be $200 or more. If you already have cable or cable outlets in your home, they most likely will not have to do any wiring. --Mus Musculus 13:33, 5 April 2007 (UTC)

As for the "if anyone knows", I bet the Comcast sales people at 1-800-comcast know the exact cost of installation. --Kainaw ^(talk) 14:00, 5 April 2007 (UTC)

Incidentally, Comcast charging high installation prices is really stupid. They should offer cheap or even free installs, then make the money back in cable fees. They risk scaring off customers which could be worth thousands of dollars in profits due to this short-sighted policy. StuRat 19:02, 5 April 2007 (UTC)

Why shouldn't they charge high install fees? They don't have a competitor. They claim satellite is a competitor, but it isn't. If you want a land-line cable, you have one choice and only one choice. Here, they try to confuse things with "Knology" as a competitor. Knology is just a Comcast reseller and they charge more to install that Comcast does. --Kainaw ^(talk) 22:01, 5 April 2007 (UTC)

There are many other forms of competition besides satellite TV, from broadcast TV, DVD rentals via Netflix, downloadable movies such as TiVo and streaming video services via DSL connections, etc. And in these days of everybody living on borrowed credit, an extra few hundred dollars on installation just may be enough to sway somebody to go with the competition. StuRat 01:13, 6 April 2007 (UTC)

Ebay Sales info

Hey All,

Does anyone know the easiest way to get information on what prices things have gone for on Ebay in a data format for free?

I know that you can perform a search using "Completed Listings Only", but I was hoping to get it in data format. I know Ebay offers "Marketplace Research", but I'd rather not pay for data (I'm a data miner!)

Is there any free 'market research'-type information on ebay sales?

I am considering just writing a VB macro to just run repeated advanced searches, locate the information within the search, and then organized it into some sort of categorical format. Has anyone done anything like this before? I did it for a local auction site for my city and it works pretty well. I don't know about Ebay though... it's pretty big. It will either take a looooong time or my IP may get banned!!

Thanks!!!

NByz 06:14, 5 April 2007 (UTC)

Before you do create a macro to do repeated searches, check the terms and conditions of your account as using it in this way may be a breach of the T&Cs. - X201 08:10, 5 April 2007 (UTC)

Well certainly achievable with some scripting, I would use maybe some php and grep and output it to a nice pretty table. What are you trying to do though? Find stats for prices of completed auctions? --antilived^{T | C | G} 08:21, 5 April 2007 (UTC)

Yeah pretty much. I'd like to be able to export a nice pretty data set of all sales in say... the last 30 days in the category X w/ the phrase Y in the title. Then apply some stats to the data once I have it. Overkill maybe... but I'm a stock market guy, and I say every market needs to be analyzed for arbitrage opportunities!

24.68.64.122 09:05, 5 April 2007 (UTC)

Windows update problem

After an automatic update of XP MCE edition, I get a message that user.exe has been moved to a different location in memory because of hhctrl.ocx. It says I should contact the vendor to get a more recent one. I thought I found one at Microsoft, but when I tried to install it, it said what I had was more recent. What should I do now? Clarityfiend 07:48, 5 April 2007 (UTC)

About 4 or 5 posts above this is a similar question (RTHDCPL.EXE illegal system DLL relocation) having trouble with the same OCX file. Have a look at that and see if it applies to your problem. - X201 14:55, 5 April 2007 (UTC)

Thanks, that did the trick. (I hate Bill.) Clarityfiend 19:32, 5 April 2007 (UTC)

Low ink consumption printer

Which is the printer/technology with the lowest ink consumption or, being more specific, cost per printed paper? Maybe some kind of inkjet printer? --Taraborn 12:39, 5 April 2007 (UTC)

Pretty much any inkjet (aka bubblejet) printer that allows you to refill your own cartridges is the cheapest. I use a BJC-210 for black and white printing. I paid $25 for a big bottle of black ink (that is actually darker than the original cartridge's ink). I refill it every other month and I've used about half the bottle in the last year. So, I'm getting about 2 years of printing for $25. It is a hell of a lot better than the laser printers here at work. Every day they want a new toner cartidge or a new drum or a new phaser... I hate them with a passion. --Kainaw ^(talk) 14:03, 5 April 2007 (UTC)

Man, if they want a new phaser, you're probably SOL until the 23rd century ;-( ! Hopefully, all they want is a fuser.

Atlant 17:16, 5 April 2007 (UTC)

It all depends on the volume and the desired quality of your printouts. You can't beat an entry level inkjet and refillable cartridges for cost per sheet, if you print low volume so that the time overhead isn't a big deal. Low cost laser printers have become quite popular in the consumer market recently, which will feature sharper, more durable printouts and operate much quicker than an inkjet. Also, Phaser is a name Xerox uses for laser printers, they perform disappointingly despite my attempts to set them to 'kill'... --Jmeden2000 17:57, 5 April 2007 (UTC)

Actually, many of Xerox's Phaser printers are crayon-jet printers; it's the line and trademark that they bought from Tektronix.

Atlant 20:03, 5 April 2007 (UTC)

I would expect an old dot-matrix printer to use the least ink, because they don't print solid letters, but just dots. StuRat 18:43, 5 April 2007 (UTC)

The trick with ribbon-based dot-matrix printers is that they never actually "run out" of ink, the printouts just get lighter and lighter. So you could print Sagan's of pages as long as you don't care if you can read them or not.

Atlant 20:06, 5 April 2007 (UTC)

• Actually, my advice is to go laser (toner). Although, the first answer about $25 for a year's ink with refillable cartriges sounds very interesting indeed. But generally speaking, ink costs more than blood! Also, a lot of inkjet/bubblejet companies scam you by selling you their printers at a really low price (see lost leader) and then bleed you dry when you come to refill your ink - it's the same principal with Gilette's razers - the 'handles' come cheap with a free blade or two, but the cartriges to buy are really expensive (although this has now changed a bit and balanced out). Toner's much better, especially for volume, and in theory it's faster - more pages per minute, and you don't have to wait for it to dry. If you're in an office environment then get a toner printer - no doubt. The only downside with toner printers is that some of the ink ones are capable of printing on CDs and DVDs - but other than that I don't like them. Oh, and some inkjets tend to do better with picture quality - if you're looking to print out a lot of photos on fancy paper - the lasers don't always support fancy odd papers - but having said that there are definitely toner printers that can do great quality printers with excellent colour matching and can even support odd papers. Rfwoolf 19:59, 7 April 2007 (UTC)

• That's a loss leader, although perhaps Bush is a lost leader ? StuRat 01:31, 8 April 2007 (UTC)

Ahh, thank-you. I've always known the term as 'lost leader' - and perhaps we need to do a redirect to 'loss leader' - I will probably say that the word 'lost leader' is a term meaning the same thing, but only when it's referred to incorrectly - you know because they have similar connotations - and if enough people started referring to the concept as a 'lost leader' eventually they would be both correct. Anyways, now I've learn to differentate between the two. ... wow, so it is true, you do learn something new every second or third day ;) (or fourth in my case). Rfwoolf 02:00, 8 April 2007 (UTC)

new technology

hi, i should give a seminar on technology that has just come so pls anybody suggest me where i can find the info and ppts. —The preceding unsigned comment was added by Chakrirajini (talk • contribs) 14:26, 5 April 2007 (UTC).

Perhaps you should tell us what exactly you wish to know. Splintercellguy 14:39, 5 April 2007 (UTC)

it will be just ppt presentation that should be any technical like a OS or any Softwares....like that so ineed info where do i get latest

Wikipedia tends to have the latest information on technical topics. Just pick one and type it in the search box. If your plan is to give a talk on "technology", you need to reserve about 200 years for the presentation just to give a very brief overview of technology. You need to focus on a single technology. For example, wireless network technology. Or, get very specific and cover bluetooth technology. --Kainaw ^(talk) 15:10, 5 April 2007 (UTC)

I suggest that you get a copy of Popular Science, they always include the latest technology. Also check out HowStuffWorks.com: [1]. StuRat 18:37, 5 April 2007 (UTC)

Some sources of new technology information: I have somehow subscribed to these in my Bloglines account, http://www.bloglines.com , (i think I ticked a box saying I like techy stuff when I set up the account and I get all these interesting things as feeds - you could set up an account and get similar info too): Wired: http://www.wired.com/ Small Business Trends: http://www.smallbiztrends.com/ The Next Net : http://blogs.business2.com/business2blog/ I also lurve New Scientist http://www.newscientist.com/ (although their site is down from my end of the web at the moment) My favourite new technology is RFID. I think it will be absolutely massive - imagine if every car was tagged with an RFID tag - and all roads had RFID receivers in the Cats-Eyes. Then they all hooked up to the net and also talked to each other. The data could be processed using some form of AI to predict where everything is heading and at what speed. It could mean no car would ever have to collide with another again! Most pedestrians are already "voluntarily" tagged with an RFID chip (its on their credit card) - so they could be demobilised if they are about to step in front of a car (perhaps a little electric shock to the knees ;o) ). Put all that info together and wow! On the down-side, Big Brother will probably want to get a piece of the action :o( Anyway, for RFID and other techy stuff, see: http://www.epcglobalinc.org/home Ronnystalker 07:49, 8 April 2007 (UTC)

Sharing photos on a LAN.

My PC is always on. I have a Picasa installation that has all my photos (~2,000) all tagged and organised. I'd like the others on my LAN to be able to access a read-only Picasa-WebUI via HTTP, or something along those lines -- even like a Picasa Web Albums that's only on my LAN. Failing this, an aesthetically appealing browser-based way of sharing photos would be great. Can anyone make any recommendations? (Note: I have almost zero knowledge of PHP, MySQL and databases.) —The preceding unsigned comment was added by 202.10.86.63 (talk) 15:48, 5 April 2007 (UTC).

Do you want all your tags and descriptions retained while it is access on LAN? I think gallery2 can do what you want, with some tinkering. Just get an all in one package of Apache, MySQL and PHP somewhere and you have an easy web-server, then install gallery2 on it and somehow import the photos in with all the descriptions and tags (the hardest part). --antilived^{T | C | G} 00:28, 6 April 2007 (UTC)

SQL Problem

I have a (SAS) dataset which has UNQ_ID, DATE, EXPENDITURE.

For each record, I require to add a variable EXP15 to the table, which stores the sum of EXPENDITURE for the rows which have same UNQ_ID, and DATE's which are within the past 15 days from the DATE in this row.

I've tried to solve this problem, but I feel my current solution can be improved. Any hint how I can write an SQL query for it will be really helpful. --Hirak 99

ALTER TABLE and triggers. You could potentially do what you're after purely with a SELECT query, but it will be rather horrid due to your "row date minus 15 days" requirement. I think you can accomplish what you're after with a trigger or just by having your application do the necessary updates. The potential gotcha is that you'll have to update the EXP15 field for practically the entire table if you ever modify EXPENDITURE in old rows or delete rows. This may not be a very desirable situation. I can't think of a way to do this that isn't fairly awful; I guess you have to decide whether you want to spend a lot of time updating the table or a lot of time on the SELECTs. Personally I would step back and see if you can work things so you don't need this EXP15 field or accomplish its intended functionality in your software. -- mattb @ 2007-04-05T16:36Z

Screencast

I am looking for software like Lotus ScreenCam that can work on Windows XP that can record my computer screen and save it to a video file. 68.193.147.179 18:49, 5 April 2007 (UTC)

Please refer to the link posted by Akamad in response to your previous query. A Google search for Screencam yields many additional options. --LarryMac 18:56, 5 April 2007 (UTC)

Web 2.0 in Museums

How are Web 2.0 technologies being employed in museums? 141.211.8.253 19:34, 5 April 2007 (UTC)Jason

They are being used to deter people who do not do homework. Splintercellguy 19:50, 5 April 2007 (UTC)

Goodness gracious, as much as I hate the mere mention of the "Web 2.0" hypeword, I think I'd break down in tears if I visited the High Museum and saw some POS terminal with a bubbling pastel-toned AJAX interface... -- mattb @ 2007-04-05T20:36Z

lastmeasure

how long does it take the Trojans and computer viruses from the shock site lastmeasure.com to start acting on your computer?--71.234.233.163 21:18, 5 April 2007 (UTC)

I'm not exactly sure Last Measure deposits trojans and viruses onto your machine, but if it does, you can easily remove with AV/anti-spyware. Splintercellguy 01:57, 6 April 2007 (UTC)

Last Measure does none of that, it's simply a product of ActiveX and Flash. So, infinite? :) -Wooty Woot? contribs 10:08, 6 April 2007 (UTC)

removed article

hi,

i added a new article, "Realm versus Realm" and it has been removed (i think it is deleted, i can not see it anymore on wiki).

I'd like to know why. I didn't add anything against which is against any laws or rules and the data was not fake, so I don't know what did i do wrong -the article could have been removed because of that-.

Thank you for the information and for your time in advance.

All the Best, Mark Kondor

ps.: the link was "http://en.wikipedia.org/Realm_versus_Realm" —Preceding unsigned comment added by FoolorganIC (talk • contribs)

According to your contributions, you made no such article. Also, checking the creating log, no article has recently been created or deleted with the name "Realm" in the title. --Kainaw ^(talk) 21:58, 5 April 2007 (UTC)

According to the deletion log, it was called "Realm versus realm", not "Realm versus Realm". The log also has the deletion reason. --cesarb 22:17, 5 April 2007 (UTC)

Thanks for the fast reply. RE: Yes, that's exactly my problem. Edited it, added with "Save page" button, tried to access it from a blank tab in my browser and it was working properly. A couple of minutes later (let's say 20 minutes) when i checked back -to revise- it said page not found. Tried to search for "RvR" and "Realm versus Realm" on wiki (generic search) - no article... ps.: i think it could be possible that it hasn't been removed but was not created at all. In that case: a)what did i do wrong (selected "Start a new article..." on main page's "Did you know" section)? b)Why was i able to browse the page for a couple of minutes on wiki with a direct link to the article?

cesarb: Thank you for the info! (and sorry for the upper/lowercase typo). Now i see it says the reason is i tried to advertise something but this is absolutely wrong:
1st) RvR is really "their word" ('WAR' makers)
2nd) WAR Online, as fully and definitely a game advert is available on wiki (but that's OK imo, there are a lot of definitions like that, e.g. "Portal (computer game)"
3rd) I spent a couple of minutes searching for "RvR" (including wiki) but didn't find it: that's why i decided to create an account here and add the topic so i can save some time of other people
The question is: What can i do now? How can i complain against the decision?
p.s.: I'm open to remove the "advert feeling" parts of the definition.

(Thanks for all the fast responses and info, and so sorry, i'm really that noob :)



update: okay, sent a message to the wiki admin who has removed the article so... hopefully he will tell me what's up related to this topic.
to "Kainaw" and "CesarB": thank you again for the response, much appreciated!

Virus on my PC!

Hi there,

Recently, my computer is affected by a virus (I don't know what kind of virus it is). First infected yesterday, around this time. Then, I want to turn it on again, but for some reason (which I believe it is a virus), it got on very, very, extremely slow. The computer seemed to not move. I was trying to get to Wikipedia and edit, but I struggled for few hours, and was unable to log on. Today, I was trying to get to Wikipedia again. This time, my account (You know in Windows XP, you are able to create several accounts) was not able to log on. Panicked, I used the "Guest" account, and to be delight, it works! But I really want my account back, and restore my files. Waht should I do? (Please do not suggest buying Anti-Virus CD!)  Smcafirst | Chit-Chat | SIGN  posted at 23:31, 5 April 2007 (UTC)

--> Please reply at User talk:Smcafirst/Requests.

I'll reply here. Use a free online anti-virus scanner of course. [2] Splintercellguy 01:56, 6 April 2007 (UTC)

When you say "Please do not suggest buying Anti-Virus CD", is that because you don't want to pay for one, or because you're opposed to using anti-virus software at all? I agree, anti-virus software should never be necessary on a computer with a proper operating system, but if yours is deficient in the area of security (as most versions of Microsoft Windows indubitably are), then running various kind of add-on security products is an absolute necessity, unless you run your PC in isolation and never connect it to the net or allow it to interact with other computers in any way at all. —Steve Summit (talk) 02:29, 6 April 2007 (UTC)

I don't run add-on security products. I gave them up a good while ago, and don't have any issues. If I'm about to run an executable from an iffy source, I run it through Virus Total; I don't run very many of those though. -- Consumed Crustacean (talk) 02:38, 6 April 2007 (UTC)

Online virus scanners won't solve anything if it's already hit. You can get a free virus scanner like Avast! or AVG Free, put it on a floppy, boot with it, and hopefully clean it. It doesn't sound like you necessarily have a virus though; a number of things could probably cause issues like that... -- Consumed Crustacean (talk) 02:38, 6 April 2007 (UTC)

If you want to you can re-install windows, it will get rid of the virus and as long as you DON'T reformat the hard drive you can get your files back by going into C:\Documents and Settings\Your_old_username_goes_here there you can acsses your old desktop and your old My Docs. It's hard thing to do but it'll get ride of the virus(if it is a virus, sound a bit like spyware or a recource hog to me) good luck --Lwarf 09:51, 6 April 2007 (UTC)

Take back what I said before, I have a better idea. Start up you're PC in Safe Mode (hold down F8 when booting up) then log in as administrator you should then be ablre to go into My Computer and get at your My Docs, if you Have file on the desktop you want take a look for them here : C:\Documents and Settings\Your_user_name_goes_here\Desktop . Once you've found all your files copy them onto a thumb drive. Now you can safly re-install windows (this time DO reformat the harddrive). --Lwarf 09:51, 7 April 2007 (UTC)