Wikipedia:Reference desk/Archives/Computing/2006 September 5

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September 5

SQL slammer worm

Hello all. I believe I am infected with this worm, but nothing has been able to detect it except about two weeks ago, when Norton informed me of a SQL buffer overflow. I googled it, and found it to have no false positives and caused by the SQL slammer worm. I used the Symantec tool to remove, but it found nothing, and I even used a shell command to find if it was using the SQL buffer overflow with a tool here http://www.f-secure.com/v-descs/mssqlm.shtml, and it found nothing. Now, as I've read, it randomly generates ip addresses and if a host happens to match that one, it is automatically infected if it isn't protected. It's been described as sometimes creating a Dos attack on the host because of the packets being sent, and I haven't ran into that, but I can tell my ping sky rockets when I play online games. I've been playing Battlefield 2, and I've noticed it will jump from around 50-100 ping, to 500-900 ping instantly, and returning back to normal. But while it reaches that ridiculous high ping, everything freezes, such as music playing in the back ground, but like my game, returns to normal. Now the logical thing would be that the worm is on my computer and is sending hundreds of packets in my network, and I'm not happy about that. This worm is from 2003 but it's now making my internet use problematic, and could also be infecting others.

I've patched with one of the Microsoft bulletins, but it still seems to be happening, and I'm actually confused. The links provided by Microsoft lead to others that lead to others etc., and I'd just like to download one thing and be over with it. I've scanned with Nod32 many times, and with AVG, both coming up with nothing. Such a small worm couldn't have embedded itself into something important really deep, or renamed itself. Any help would be appreciated! --Hellogoodsir 01:00, 5 September 2006 (UTC)

make sure u updated windows www.windowsupdate.com do all the priority updates and and make sure u got service pack2. u probably dont have anything. i wa getting warnings from my antivrius for awhile and i realized that it was just some dos script i downloaded that iw anted to run to screw aroudn with this server. so perhaps you tried to use a hack on someone a few months ago saved the file and its detecting that? if so you could just delete the file. i would imagine norton would tell you the infected file name if u really had one. i suspect the gaming problem is related yto something else Modesty84 00:58, 7 September 2006 (UTC)

SQL Slammer is a worm which resides only in the computer's memory, and never gets written to the disk; simply turning the computer off removes the worm, and no antivirus can find it on the disk (because it's not in the disk). However, if your computer isn't patched, it will get reinfected the next time it connects to the Internet. To fix it, simply install the fix for the vulnerability the worm depends on and reboot the computer. Since you say you are already patched and thus not vulnerable, it's possible that your firewall was crying wolf by informing you of an attempt by someone else to exploit the vulnerability on your machine. There are other explanations for the freeze you see in the game (probably some misbehaved piece of hardware or software). --cesarb 17:26, 7 September 2006 (UTC)

Windows 2003 Server

I have a question that google cant answer.

I want to direct the users' folder to a centralized location. What type of folder(s) can be redirected with Win Server 2k3 and what are the advantages of making use of folder redirection? What kind of folders and what are the advantages of using this on a network?

OK i guess it a security function to have your data moved to one place for easier backup purposes.

Thanks. 165.165.189.28 06:05, 5 September 2006 (UTC)Jason

I don't use "folder redirection". I have a JBOD server (linux) running Samba. Each user has two directories on it, a private one and a public one. I map them to H: for their private one and P: goes to the list of public directories. I link "public" in their private directory to their public directory - just so they can drag/drop files from private to public easier. Then, I tell them that if they want files backed up, it better be on the H: drive. If they want to share a file without people, put it in their public and everyone else can see it in P:\\your_user_name. Of course, I could try to redirect the "My Documents" directory to their H: drive, but I don't worry about it because they are all good at using the H: drive. And - to answer the obvious question: Why Samba? None of the developers here use Windows. They use Linux. So, they map their private/public directories with NFS. --Kainaw ^(talk) 13:53, 5 September 2006 (UTC)

explain blogging

See Blogging. Harryboyles 06:53, 5 September 2006 (UTC)

Does playing games in PC affect its performance or Hardware by any means?

Hi friends...I wanna know if one uses PC as a Games machine consolidatly and keeps on playing all the time continously, then does it in the mere future slow down other applications or reduce the potential of the hardware simply?..What makes me to ask is since playing games cause CPU to go 100% usage thereby generating more heat and reducing naturally CPU's lifetime fastly and so is the HDD....I confess if there's any innocense in my question,I admit though...My point is that is PC most favourable and preferable and reliable at playing games as we do all with game consoles?

Well, on the software sense i can't see much problem you'd have with slowing down of applications, maybe a little increase in fragmentation of disk, but that's easily fixed. On the hardware part, when the CPU is running at 100% it's running well within its designed operating area, that is unless you've overclocked it, i can't imagine you could cause much damage or reduce lifetime as long as your cooling is up to the job. Benbread 11:14, 5 September 2006 (UTC)

I've never heard anything about gaming damaging a PC. Theoretically, highly-demanding applications like games might reduce the lifetime of your CPU, but it's almost certainly too small to notice. Sum0 21:17, 5 September 2006 (UTC)

If you're downloaded free games off the Internet, you may well be getting spyware/malware on your computer. Try running AdAware or Spybot - Search and Destroy, to remove them, if this is the case. StuRat 02:22, 6 September 2006 (UTC)

Some games install drivers (for instance StarForce) which stay running all the time and can interfere with the normal operation of the system (as well as consuming a bit of resources). You can also have HD fragmentation and junk accumulating in the registry; both slow the system down. Notice that all are software issues, and not limited to games; if you reformat and reinstall, the machine would work as new. Unless you have a defective heatsink and/or fans, the reduction of the CPU or HD lifetime should be so low as to be lost in the noise. --cesarb 17:15, 7 September 2006 (UTC)

Stay away from starforce, don't download free games (if you download expensive games FOR free make sure the keygen you're using isn't a trojan), delete program files left over from uninstalls, and there will be absolutely NO degradation in system performance whatsoever. As for CPU life, it's so many centuries that cpu life never matters unless it's rediculously overclocked (like IBM's several-hundred-gigahertz test or toms hardware's 5ghz test). --Froth 23:24, 8 September 2006 (UTC)

Free web domains

Can anyone recommend a good free domain that doesn't require forum posts or a certain amount of daily views ? Robmods 16:15, 5 September 2006 (UTC)

• 50megs.com does the job for me. - Mgm|^(talk) 17:40, 5 September 2006 (UTC)

Here's an excellent provider with php (with gd!), perl (i think), 10mb of mysql, 1gb transfer, the works 100webspace --Froth 23:27, 8 September 2006 (UTC)

problems connecting to the Internet with Linux

I am using Red Hat Fedora Core 3, and a fairly standard 28k modem, by Multi Tech Systems. Every time I connect to the Internet, the first time I try, it connects then cuts out. The computer tells me "The PPP daemon died unexpectedly" When I try to get a report of the problem, it tells me it can't because the "debug" option is not switched on. This doesn't seem logical, because I asked this question before on Wikipedia, and someone told me how to switch it on, and I have done so. Even now, having put the debug option in the relevant file (/etc/ppp/options) it still does the same thing. After cutting out, it asks me if I wish to turn the debug option on, and I click yes, and then, when I connect for the second time, it works fine. My start up string is at&f (I have also tried at&f followed by ATZ), which is on the advice of my ISP, so I don't know if that makes any difference. Can anyone tell me what to do? The Mad Echidna 20:40, 5 September 2006 (UTC)

Are you sure it connects? I think I've had the same error message when it wasn't actually connecting. If it connects OK the second time, I'd put up with it. Modems are a nightmare in Linux and I'd be grateful for any functionality, however buggy. Rentwa 21:02, 5 September 2006 (UTC)

Hi, thanks for the suggestion, and thanks for lowering my expectations, because I was thinking of just dealing with it. By "connects", I meant that the phone clearly answers, and the modem makes its funny squealing noises and all that. This means it's costing me a phone call each time, which is why I'm hoping to fix the problem. 203.221.127.134 23:06, 5 September 2006 (UTC)

I don't know what else to suggest, really. Try running in console mode (you'll need to download Lynx (text only browser) if Red Hat doesn't have it, so you can be certain you're connecting) and with limited services running the logs should be simpler, and you can debug manually (there should only be about 5 - 10 relevant things running at that level). If it runs fine then I'd deduce the problem is higher level like X or your browser and I'd run a mile! Rentwa 06:18, 6 September 2006 (UTC)

By "fairly standard", do you mean a Hayes-compatible hardware modem, or do you mean a cheap "winmodem" of the sort that comes with every computer? --Serie 20:59, 7 September 2006 (UTC)

C Programming

I'm currently learning how to Program in C (using K&R ). I wrote a calculator program which uses command line parameters to specify the operations to perform; (exercise 5-10 in K&R) this involves having argc and argv[] as parmmeters of main(). However on testing the program I discovered than when "*" is used as a command-line parameter the index of the directory the .exe is in (i.e. a list of the files in the directory) is passed to the program in argv[]. ("^" is reserved also, but instead it causes the string "More?" to appear at the command prompt!) I'm using the command promt of windows XP to execute my programs and my compiler is the one used by Dev-C++. My question is: is this a "feature" of MS-DOS/windowsXP command prompt or some strange thing my complier does or is it some feature of C or what? Also: any suggestons to stop it happening? I can use "'s around the offending characters to have them be passed correctly but this is ugly for a calculator! Thanks Tomgreeny 21:13, 5 September 2006 (UTC)

It sure sounds like that * is being expanded into a list of all files in the directory (just as j* would expand to all the files in the directory that begin with a j). This is a process called "globbing". Now, normally DOS/Windows and Unix handle globbing very differently. On unix the shell (bash or whatever) will glob the * (create the list of files) before it calls a child program; but dos and its descendents won't (at least they didn't the last time I wrote a windows program, which was some time ago) - they just pass * as one of the arguments. Now, some C compilers on DOS/windows try to help you out by adding in a globbing library - for comparision, here's info about how DJGPP did globbing, and how you'd disable it here. I don't know how Dev-C++ works, but it looks like it's really gcc on mingw, so I'll bet it does things the same (or similar) way. I found this page which discusses how to disable globbing in that environment - give that a shot. -- Finlay McWalter | Talk 21:29, 5 September 2006 (UTC)

Yeah, adding the int _CRT_glob = 0; line at the top fixes the * globbing thing. But you're right about ^, it doesn't work either way. That's not the compiler's fault, I think - perhaps it's some weird windows shellism. You can always pass args in like this mycalc.exe "1 * 2 ^ 3". In that case arg[1] is the single string 1 * 2 ^ 3, which you'd need to parse (strtok) - but that doesn't suffer from the ^ issue. -- Finlay McWalter | Talk 23:00, 5 September 2006 (UTC)

Thanks alot dude, very informative, the int_CRT_glob =0; code works fine. ^ seems to be used to insert extra paramers (not sure why you'd want to do this). Thanks again Tomgreeny 15:54, 6 September 2006 (UTC)