Wikipedia:Reference desk/Archives/Computing/2009 May 25

= May 25 =

Is Facebook useful?
I guess this is a pretty dumb question. The obvious response is "useful to whom?"

I'll ask in a different, more specific, way.

Do people who answer questions at the Reference Desk find Facebook useful enough to be worth using? If so, what things do you use it for?

Thank you. CBHA (talk) 00:49, 25 May 2009 (UTC)


 * I keep up with what friends are doing who I normally wouldn't see and play games. Dismas |(talk) 00:55, 25 May 2009 (UTC)


 * I really don't see the point. Why would I want everyone to know what I did today, what I like or don't like, what music I listen to, what shows I watch, and what the hell would I do with perhaps thousands of so-called "friends" I will certainly never meet?  Astronaut (talk) 01:21, 25 May 2009 (UTC)


 * You don't have to add "friends" who aren't actually your friends. As for why they'd want to know, well, they might, they might not. I sort of like to see what people are up to without having to get in touch with them more directly. It's a nice passive mix of voyeurism and exhibitionism. That being said, I've noticed that the people I communicate with most regularly on facebook are the people I see most often anyway, so I'm not sure it is much more than a mixture of an address book and a way to peek in on people's lives without them directly knowing. --98.217.14.211 (talk) 01:51, 25 May 2009 (UTC)


 * I have found that it is easiest to stay in touch by telephone and email. Because these are direct point-to-point communication methods, it eliminates the vast majority of "frivolous" communications.  Nimur (talk) 18:03, 25 May 2009 (UTC)
 * I have, in the past, been subscribed to two polish social sites (one of them being nasza-klasa.pl), but have stopped using my accounts and/or blocked them, because it was just taking up too much of my time, looking at photos of strangers or what not. If anyone wants to contact me, my details have been unchanged for years now, and even if need be, they're easy to find online because of the business I'm in. Friends have been trying to coerce me to register with Facebook, but I just don't seem to be needing it. What for? Too colourful, floopy, pointless for me. Texting and e-mails are what I use, like Nimur. Cheers, --Ouro (blah blah) 06:58, 26 May 2009 (UTC)
 * Ps. Another reason: anything mainstream is kind of off-putting for me. I choose my own paths. --Ouro (blah blah) 07:00, 26 May 2009 (UTC)
 * I don't see anything very useful there - it seems to be mostly yet another way to soak up my time. SteveBaker (talk) 21:23, 26 May 2009 (UTC)

Where is the Bluetooth headset article?
I was hoping to read a lot about how people with these new headsets on appear to talk to themselves (like Autistics do) and how using them could lead to a world of hurt. Unfortunately, there's no such article, and making it would get it speedy-deleted because admins on WP nowadays have a hair-trigger-finger on the deletion button.

So will someone please create Bluetooth headset for me? --70.254.195.100 (talk) 00:52, 25 May 2009 (UTC)
 * We have Headset (telephone/computer), but it looks like it could use some tidying up — Matt Eason (Talk &#149; Contribs) 01:01, 25 May 2009 (UTC)


 * I created the stub. Hopefully others can continue to add to it, and I'll add to it myself when I have time/resources available. Shadowjams (talk) 06:21, 25 May 2009 (UTC)

Timelapse from a webcam
Is there software available that can take a photo every x seconds/minutes using a webcam, and save it to the hard drive? —Preceding unsigned comment added by 86.177.122.55 (talk) 02:05, 25 May 2009 (UTC)


 * You could probably write a bash script to do this fairly easily. Got any friends who know linux? --Shaggorama (talk) 03:54, 25 May 2009 (UTC)


 * Microsoft has a program called "timershot" that does this. It's available as part of their Power Toys. Just google for "timershot power toys microsoft". There's also an open source webcam software out there called Dorgem at that works well, and has a windows binary. It has been discontinued, but the old versions of the software should work. Shadowjams (talk) 06:15, 25 May 2009 (UTC)


 * Hm, that's too bad, the installer refuses to install on Vista, claiming it doesn't work on anything earlier or later than XP. Tempshill (talk) 06:26, 25 May 2009 (UTC)


 * Would it be possible to rip the dll/exe out of the package and just run it manually? That's worked on some drivers that refuse to work in Windows 7/Vista. Shadowjams (talk) 06:42, 25 May 2009 (UTC)


 * Try running the installer in compatibility mode for Windows XP. (Right-click the installer-->Compatibility)--Xp54321 (Hello! • Contribs ) 14:56, 25 May 2009 (UTC)


 * I tried the timershot program, but windows froze twoce when i right clicked on the exe to try and run it in compatibility mode(on vista)!. Dorgem seems like a good program, but it only saves 1 image, i.e. when it takes the next picture, it overwrites it, whereas i want a series of pictures. Anyone know how to get it to save each picture individually and not write over the previous one. Surely there must be some other programs out there to perform this sort of task! Edit: just found the store as avi setting! —Preceding unsigned comment added by 86.177.120.86 (talk) 15:29, 25 May 2009 (UTC)


 * You can fix that by putting a flag in the filename. Typically the timestamp. Then it won't overwrite each set of pictures. It will do exactly what you're talking about with JPGs (and the AVI as you discovered). Shadowjams (talk) 21:22, 25 May 2009 (UTC)


 * How can i put a timestamp flag in the filename? Thanks. 86.177.120.86 (talk) 23:03, 25 May 2009 (UTC)


 * It's been a while, but in the help there's a list of variables you can use in the captions and in the filenames. Things like %t. You can put that in your file name, so when you specify the path to write the output, put "picture%t.jpg" if I remember. Shadowjams (talk) 00:37, 26 May 2009 (UTC)


 * Thanks! Works Like charm! It's a shame the person who made dorgem stopped developing it, but it still pretty good for something that is unfinished! 86.177.122.74 (talk) 13:45, 26 May 2009 (UTC)

free (gratis) software for students
Which companies give their proprietary software for free for students? I know that Microsoft and Autodesk both do it, but are there any other companies? -- hello, i'm a member  |  talk to me!  04:05, 25 May 2009 (UTC)


 * Don't know about Autodesk but Microsoft generally don't give out software for free. They, along with almost all other software companies (Adobe comes to mind), do provide a heavily discounted version of their software for students though. --118.90.137.39 (talk) 05:31, 25 May 2009 (UTC)


 * They do. Exhibit A: DreamSpark -- Consumed Crustacean (talk) 05:41, 25 May 2009 (UTC)


 * Splus (statistical software) I think is available for students on a limited basis, maybe for free. Shadowjams (talk) 06:17, 25 May 2009 (UTC)


 * As the OP suggested, Microsoft does release Visual Studio Express and SQL Server Express as free downloads. Although they have some built in limitations that make them unsuitable for large scale commercial application development, they are very much suited for student use.  -- Tcncv (talk) 06:30, 25 May 2009 (UTC)


 * Where I went to school there was a program where student licenses of many microsoft products (but not Windows or Office) could be gotten for free and you could borrow a "corporate" multi-install disk. I was under the impression that Microsoft sponsored this program, but I can't say for sure, I never took advantage of it. (I ran Linux.)  I think this only applied to Comp. Sci. students. APL (talk) 06:56, 25 May 2009 (UTC)


 * That one is the MSDN Academic Alliance. It's cheaper, but the school still needs to pay some money, which is obviously coming out of your tuition. Much of the normal MSDNAA software is on Dreamspark as well now. I have no idea if schools need pay for that, but it doesn't seem to be restricted to students of certain departments/faculties. -- Consumed Crustacean (talk) 07:01, 25 May 2009 (UTC)


 * That doesn't count because they are available for everyone. F (talk) 10:25, 25 May 2009 (UTC)


 * Companies like Opera give away their proprietary software to anyone. But perhaps that's not what you have in mind. Systat gives away Mystat. -- Hoary (talk) 10:13, 25 May 2009 (UTC)

Any more companies? I'm compliling a list. And yes, I knew about Dreamspark. -- hello, i'm a member  |  talk to me!  17:30, 25 May 2009 (UTC)


 * The free versions that Autodesk gives away are typically horribly crippled. My son (who is a student) needed a copy of Maya for his coursework - but the free version can't save in any file format other than it's own encrypted form that regular Maya can neither read nor write.  All of the MEL-scripting stuff is disabled - plugins are not allowed - when you render something, it adds an ugly "watermark" across it - and so forth.  Having said that, the $250 student bundle they are doing is an incredibly good deal - it comes with 4 of their other packages as well as a full version of Maya.  There is a yet cheaper version out there - but it has a license that expires 14 months after you buy it. SteveBaker (talk) 21:21, 26 May 2009 (UTC)

Open .desktop files (Linux)?
Does anyone how can I open .desktop (dot desktop) files from the command line? I needed to do it for a project I am working on... (a solution for GNOME or KDE was good enough).... does anyone know that? Thanks _ Hacktolive (talk) 09:25, 25 May 2009 (UTC)


 * works in KDE4. Probably  also does this, but I do not have Xfce, Gnome or Konqueror installed. MTM (talk) 11:56, 25 May 2009 (UTC)
 * Thanks, kde-open works! (even on GNOME with KDE libraries), however... I still can't find the GNOME command to open .desktop files... gnome-open and xdg-open simply open the file on a text editior... Hacktolive (talk) 15:15, 25 May 2009 (UTC)


 * The GNOME solution is . --194.197.235.28 (talk) 15:15, 25 May 2009 (UTC)
 * Damn, seems to be a bug. thanks anyway   Hacktolive (talk) 20:18, 25 May 2009 (UTC)

Two internet connections
On a Windows XP computer that is connected to the internet via an ethernet cable, is it possible to use a wireless network card to connect to a different internet connection at the same time, so that for example you could have Firefox using the ethernet connection and another browser using the wireless connection? —Preceding unsigned comment added by 82.44.54.169 (talk) 11:10, 25 May 2009 (UTC)
 * It looks like ForceBindIP will do this. -- BenRG (talk) 13:14, 25 May 2009 (UTC)


 * Windows XP will gladly create two internet connections and your computer can have two IP addresses. When a particular program makes a request, Windows will try to use the best network connection for that particular socket.  This may mean the faster connection, or "something else" (simplest routing table, etc).  If you want to explicitly choose the network connection that is used in Firefox, you can go to the Advanced Connection settings (Tools menu, Options Menu, Advanced Tab, Network Tab, Connection Settings option).  Other programs may have similar control settings, but many will simply use the automatically detected "best" network connection.  This can be a problem if the two network cards do not both connect to the same network (as in some setups with a slow internet connection and a fast LAN-only connection).  Nimur (talk) 18:10, 25 May 2009 (UTC)
 * So what do I do in the Connection Settings? I have the options "no proxy", auto detect" and "manual proxy" —Preceding unsigned comment added by 82.44.54.169 (talk) 04:42, 26 May 2009 (UTC)
 * As far as I know Firefox doesn't actually have this option, nor does most other networking software. You could set one of your browsers to use an outside proxy, then set up routing such that all traffic to the proxy's IP address goes through the second interface, but that's probably not what you want. -- BenRG (talk) 09:39, 26 May 2009 (UTC)
 * So it's impossible? —Preceding unsigned comment added by 82.44.54.169 (talk) 11:25, 26 May 2009 (UTC)
 * You mean what you asked for in the original question? I think it's possible, but you need to use ForceBindIP, not the browsers' built in connection settings. -- BenRG (talk) 20:35, 26 May 2009 (UTC)

add ons disabled.
Hi, I stupidly decided to install google chrome which I have now removed and I have installed IE8. However since installing chrome, and now still, every time I load a webpage a pop up bar appears saying "Internet Explorer is currently running with add-ons disabled. Click here to manage, disable or remove your add-ons"

What is going on as I have no idea what to do??? please please help.Scraggy4 (talk) 12:37, 25 May 2009 (UTC)


 * It may be that you've accidentally set your default browser, or whatever icon you're using to launch IE, to run IE in "safe mode". How exactly are you launching IE? - IMSoP (talk) 16:34, 25 May 2009 (UTC)


 * It's ok now I've just had the idea of googling "add-ons disabled" and came up with the answer. thanks anywya  —Preceding unsigned comment added by 86.20.197.104 (talk) 16:44, 25 May 2009 (UTC)

i-tunes
what is the filename for video clips that can be seen on i-tunes80.254.92.89 (talk) 13:21, 25 May 2009 (UTC)


 * Don't you mean "file extension" (or, more precisely, "file format") rather than "file name"? I never use iTunes, though, so I do not know. --Andreas Rejbrand (talk) 14:10, 25 May 2009 (UTC)
 * MPEG-4? You could have a look at Itunes for more information. -- Kateshort forbob  14:58, 25 May 2009 (UTC)

assigning new functions to keys in Linux
Hi, I would like to know if there is a way to assign a new function to a key? For example, I want a key on the numeric key pad to function as the tab key so that I don't have to use my left hand to tap tab to navigate to another field while entering numerical data. Is there a way to do this, say on Mandriva? --117.204.80.196 (talk) 14:45, 25 May 2009 (UTC)

You can modify your keyboard layout directly too, but if you don't need that much control you can use xmodmap. Use the program xev to find out the keycode for the key you want to remap, then you can remap it to tab with 'xmodmap -e "keycode = Tab"'. Put the keycode = Tab part to ~/.xmodmap and it will automatically load in future sessions. --194.197.235.28 (talk) 15:13, 25 May 2009 (UTC)

Getting rid of virus when you can't boot
Hey, I just received an old computer from a friend of mine. Problem is, it can't boot into Windows XP. Well, it can sort of, but as soon as you get to the login screen an error saying drwtsn32 failed to initialize appears, and upon clicking OK, the computer reboots. I suspect a virus of some kind. Question is, what tools (preferably free) would allow me to run a virus/spyware scan on the hard drive, without it having to boot into Windows? Are there any LiveCD versions of Linux that come built-in with antivirus tools I can use to scan a Windows partition? The computer doesn't have internet access, so I can't update definitions if I have an old .iso... I'd really prefer not to reformat the HDD, and that's why I'm looking into these other alternatives. Thanks for all the help I can get! 141.153.216.72 (talk) 18:55, 25 May 2009 (UTC)


 * One question: Have you tried booting Windows into Safe Mode?  Tempshill (talk) 19:49, 25 May 2009 (UTC)
 * Yes, and I get a blue screen as a result. (OP) 141.153.215.48 (talk) 22:35, 25 May 2009 (UTC)
 * I googled "antivirus boot cd free" and the first link was this list of free antivirus CDs. If you really think this is a virus rather than some configuration problem &mdash; you haven't mentioned why you think it's a virus, but let's say it's a significant probability &mdash; I would (a) go ahead and try one of those boot disks; but you could also (b) detach the hard disk and attach it to a working computer of yours that already has some antivirus software on it that can scan the drive.  Tempshill (talk) 23:24, 25 May 2009 (UTC)


 * You could run clamav from a boot CD. Googling turned up the clamav live CD, which allegedly is updated hourly with the latest virus definitions by an automated script. (Here's the script.) -- BenRG (talk) 23:27, 25 May 2009 (UTC)

ALternate DNS Server
I'm using Mac OS X 10.5.6 with Firefox v3.0.10 and I have two alternates set up, Public Root and OpenNIC. But when I try it after turn one on and turn off the main one all new pages just look a blank page and when i open a new tab and try to type in an address there it stays on google-toolbar page installed by the google toolbar. How can I fix this? --Melab±1 &#9742; 19:55, 25 May 2009 (UTC)
 * Also when I change it back to the main setup it works fine.
 * If I understand correctly, you are trying to use one of the public root servers (i.e. [a-m].root-servers.net) as "your" server. This won't work, as Mac OS X's resolver expects the DNS server it queries to provide recursive service (i.e. the DNS server does the research and replies with a final answer), and the root servers don't do this (their job is to act as authoritative servers for the root zone, not do your research for you).
 * If you want to see the difference, open up your terminal and try the following commands:
 * This'll ask the name server at 4.2.2.1 (a Level 3/Verizon recursive server) to look up www.apple.com; if you look at the "ANSWER SECTION" it prints, you should see the www.apple.com is an alias of (CNAME record) www.apple.com.akadns.net, which has the address (A record) 17.112.152.32.
 * This'll send the same query to 198.41.0.4 (aka a.root-servers.net); note that the response says "WARNING: recursion requested but not available", and contains no ANSWER SECTION, but it does have an AUTHORITY SECTION listing a bunch of NS records for "com." pointing to [a-m].gtld-servers.net.  This is its way of saying that it doesn't have the answer, and isn't going to find it for you, but if you want to do the research yourself the next step is to send the same query to one of the authoritative servers for the "com." zone.  If you were to send the query to one of them, they'd similarly refer you to Apple's name servers, which would finally answer the question.  Or rather, they'd give you that CNAME record, telling you that you have to go through the process again to track down an authoritative server for www.apple.com.akadns.net... you can see why having a recursive server do this for you is handy. -- Speaker to Lampposts (talk) 21:04, 26 May 2009 (UTC)
 * This'll send the same query to 198.41.0.4 (aka a.root-servers.net); note that the response says "WARNING: recursion requested but not available", and contains no ANSWER SECTION, but it does have an AUTHORITY SECTION listing a bunch of NS records for "com." pointing to [a-m].gtld-servers.net.  This is its way of saying that it doesn't have the answer, and isn't going to find it for you, but if you want to do the research yourself the next step is to send the same query to one of the authoritative servers for the "com." zone.  If you were to send the query to one of them, they'd similarly refer you to Apple's name servers, which would finally answer the question.  Or rather, they'd give you that CNAME record, telling you that you have to go through the process again to track down an authoritative server for www.apple.com.akadns.net... you can see why having a recursive server do this for you is handy. -- Speaker to Lampposts (talk) 21:04, 26 May 2009 (UTC)
 * This'll send the same query to 198.41.0.4 (aka a.root-servers.net); note that the response says "WARNING: recursion requested but not available", and contains no ANSWER SECTION, but it does have an AUTHORITY SECTION listing a bunch of NS records for "com." pointing to [a-m].gtld-servers.net.  This is its way of saying that it doesn't have the answer, and isn't going to find it for you, but if you want to do the research yourself the next step is to send the same query to one of the authoritative servers for the "com." zone.  If you were to send the query to one of them, they'd similarly refer you to Apple's name servers, which would finally answer the question.  Or rather, they'd give you that CNAME record, telling you that you have to go through the process again to track down an authoritative server for www.apple.com.akadns.net... you can see why having a recursive server do this for you is handy. -- Speaker to Lampposts (talk) 21:04, 26 May 2009 (UTC)

Security problems of "mount" on Linux?
Could someone please explain me if it is dangerous to give access to the mount command to non-root users? I am planning to do that on a project I am working on, but I was told that was insecure... is that true? If so, then why is it insecure? Thanks __ Hacktolive (talk) 20:56, 25 May 2009 (UTC)


 * A non root user could mount the physical device of the root partition with whatever umask he wanted, giving full access to whatever devices are on the system. There may be other ways to do it. Shadowjams (talk) 21:19, 25 May 2009 (UTC)
 * I see... and that is the only security problem with "mount"? If so I will probably allow non-root users to use/launch my app as root, and then I make the app itself only mount filesystems in read-only mode... This should be safe, right? __ Hacktolive (talk) 23:43, 25 May 2009 (UTC)


 * Use fstab to allow non-root users to mount the drives you want them to be able to access, with the permissions you pre-define. The fstab article should explain it, but if you have questions feel free to ask them here. Shadowjams (talk) 00:46, 26 May 2009 (UTC)


 * Actually I've mispoken here. Your mount command typically will have permissions like this: -rwsr-xr-x 1 root root. You of course don't want to give non root users write access to it, but non-root users can execute it as root, that's the SUID (the s) part. Here is an explanation of SUID: . If mount doesn't have any vulnerabilities, this shouldn't be a problem (because the command will control access itself, despite running with root permissions). But if the mount program could be changed, or has a vulnerability, this could be a problem and allow a user to run something with root permissions. So it can be ok to let a user run mount, but there could be problems.


 * Sorry for confusing the answer. I misunderstood your question to be asking what would happen if a non-root user could mount anything, not "use the mount command" as you actually said. Shadowjams (talk) 01:02, 26 May 2009 (UTC)


 * Shouldn't "mount" only allow non-root users to mount things that are already in the fstab file? Usually that's enough to mount a floppy disk, or a usb keychain drive, or whatever. APL (talk) 00:51, 26 May 2009 (UTC)

From the mount man page : (iii) Normally,  only  the superuser can mount file systems. However, when fstab contains the user option on a line, anybody can  mount  the corresponding system. APL (talk) 00:55, 26 May 2009 (UTC)
 * Yeah, you're completely right. I was misusing "mount" as an action and "mount" the command. Mount the command should impose the appropriate security. There have been vulnerabilities in the past (See this: ). Shadowjams (talk) 01:30, 26 May 2009 (UTC)

OK, thanks to all, I wll try to see if I can use the /etc/fstab thing. Thanks _ Hacktolive (talk) 23:10, 27 May 2009 (UTC)

CentralNic DNS records or Root Zone File or whatever
How can I get the dns record or root zone file or whatever is used by CentralNic for the operation of their subdomain registry? Content may look like this: ns3.centralnic.net	a	62.197.40.234 ns0.centralnic.net	a	213.146.149.169 ns2.centralnic.net	a	72.3.240.16 ns1.centralnic.net	a	213.146.149.134 ns5.centralnic.net	a	194.169.218.17 ns4.centralnic.net	a	194.169.218.16 ns6.centralnic.net	a	194.0.2.2 us.com	a	69.64.147.249 us.com	mx	10 1498931680.pamx1.hotmail.com us.com	ns	ns4.centralnic.net us.com	ns	ns6.centralnic.net us.com	ns	ns5.centralnic.net us.com	ns	ns2.centralnic.net us.com	ns	ns0.centralnic.net us.com	ns	ns3.centralnic.net us.com	ns	ns1.centralnic.net --Melab±1 &#9742; 21:36, 25 May 2009 (UTC)
 * In general, you can't. You can request a copy of the zone file with an AXFR (zone transfer) query, like this:
 * ...but unless you run this command on one of their approved (/trusted) secondary servers (apparently ns[1-6].centralnic.net), the primary server will refuse the request. This is a standard security measure. -- Speaker to Lampposts (talk) 01:03, 27 May 2009 (UTC)
 * ...but unless you run this command on one of their approved (/trusted) secondary servers (apparently ns[1-6].centralnic.net), the primary server will refuse the request. This is a standard security measure. -- Speaker to Lampposts (talk) 01:03, 27 May 2009 (UTC)