Wikipedia:Reference desk/Archives/Computing/2009 December 2

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December 2

rundll

Can you change the rundll without reinstalling windows? —Preceding unsigned comment added by 152.31.162.62 (talk • contribs)

Yes, you can change it, e.g. by using a hex editor in another OS on the computer. But almost all changes you do to it, will make Windows malfunction. Exactly what do you mean by "change"? --Andreas Rejbrand (talk) 01:11, 2 December 2009 (UTC)

It's just a file (albeit a system one), so you can certainly change it. But why would you want to? If you think it's infected with a virus, you need a more thorough clean than just changing this file. And if you're simply worried because you see lots of "rundll" instances in the Windows task manager, that's not necessarily an indication of a problem (lots of things use rundll to work, most of them benign). If you're worried about the safety and security of your system, a virus and spyware scan is in order. If you're getting crashes in rundll, they're probably really crashes in some program that's just using rundll. And if rundll appears implicated in your system being entirely non-operational, it may be time for a restore to a safe restore point. -- Finlay McWalter • Talk 01:15, 2 December 2009 (UTC)

Rundll

Can you change the rundll on a computer. I got rid of some viruses but the rundll is still looking for them and I don't want to reinstall if I don't really have to —Preceding unsigned comment added by 152.31.162.62 (talk) 01:11, 2 December 2009 (UTC)

OK. You most likely do not want to change the system component rundll32.exe. Perhaps the unwanted software is located in autostart? Run msconfig and see if you find anything. --Andreas Rejbrand (talk) 01:15, 2 December 2009 (UTC)

Briefcase Blues

I'm using a briefcase as a simple way to back up my documents and pictures onto my iPod. Should be pretty simple, right? It all works fine for the Pictures folder, as well as a third folder, but the Documents folder just doesn't work. Nothing appears under its status (as in "up-to-date" or "needs updating"), and when I click "Update this item," only the "Please wait while Briefcase checks your files" window opens up briefly, then disappears. I try "Update all items," but apparently 2 gigabytes isn't enough memory to handle it all. I could go through and manually update the items within, but it doesn't let me update the subfolders, saying I should update the parent folder. This leaves me unable to back up anything I created after having made the Briefcase. What should I do?--The Ninth Bright Shiner 01:13, 2 December 2009 (UTC)

Briefcase has a spotty reputation for doing weird things (but not as spotty as Roaming Profiles, another of MS's not-quite-good synchronisation solutions). Personally I wouldn't trust briefcase, but instead use rsync. rsync works the same way (at least for a one-way sync, like you're doing) and is generally extremely reliable and weirdism free. -- Finlay McWalter • Talk 02:14, 2 December 2009 (UTC)

Sounds good, I'll look into it. Thanks! But one more problem...how should I dispose of radioactive waste the old Briefcase file? Just delete it...right? I don't want it to voraciously claim any more of my files, not after the Calgary pictures incident...--The Ninth Bright Shiner 02:27, 2 December 2009 (UTC)

I wonder if this is relevant but I don't think iPods are very good back-up devices. Please consider an additional back-up solution if your iPod is the only back-up you currently have. Kushal (talk) 15:29, 7 December 2009 (UTC)

Contextual search

Is there any search engine that can make contextual searches, i.e. intersect the set of results with the set of pages on a particular topic? I just tried the Google search "rings in GAP", because I want to find out more about rings as they are used in GAP. But most of the matches are irrelevant, not about mathematics at all. It would be nice with a search syntax like "rings in GAP topic:mathematics", so that all returned pages are (likely) about mathematics. It would also be good if you could restrict the matches to be case-sensitive, so that only "GAP" is matched, and not e.g. "gap". --Andreas Rejbrand (talk) 01:20, 2 December 2009 (UTC)

This page from Google tells you how to get more out of your search, but doesn't say how to get the results you describe. Astronaut (talk) 13:49, 2 December 2009 (UTC)

Over at Bing, they provide a different set of controls and advanced search options. Astronaut (talk) 14:01, 2 December 2009 (UTC)

Easiest way to copy short clips from a DVD

I want to copy short clips from a DVD to an avi or mp4. Technologically speaking, what's the quickest and easiest way to do this? (using WinXP :( ) --Alecmconroy (talk) 03:33, 2 December 2009 (UTC)

(edit conflict)You need to first rip & decrypt the DVD onto your hard drive before you can do anything with the DVD. Try DVD Decrypter. If you are questioning the legality of this, it is not illegal to decrypt and rip the DVD if you do not utilize the decrypted data for commercial profit (that's piracy). DVDs are licensed for private home viewing; this is a different form of private home viewing.  Buffered Input Output 12:28, 2 December 2009 (UTC)

The DMCA (in the USA) makes it pretty clear that using the above method is illegal, and the media companies seem to agree. As I'm hoping not to start a debate about this very hot topic, I personally like to think ripping DVDs for personal use falls under the Fair Use exception. This may or may not hold up in court. I don't know of any cases where this was argued, but if there are any it would bring more merit to my views as well as the views of many consumers. Unfortunately circumventing the DRM using DVD Decrypter and other similar programs is the only way of doing what you want to do... aside from videotaping your TV screen :P Caltsar (talk) 20:14, 2 December 2009 (UTC)

They will never find out unless you're dumb and tell them, or start selling or distributing your decrypted dvds —Preceding unsigned comment added by 82.44.55.75 (talk) 20:34, 2 December 2009 (UTC)

Interestingly enough, shortly after posting here I read something about a guy in Denmark who turned himself in for doing just that. I'm hoping this sets some precedent for the US laws to be set right in the near future. Caltsar (talk) 15:53, 3 December 2009 (UTC)

The legal question is separate from the technical one. The easiest technical way is to use something like HandBrake, which makes ripping DVD chapters really easy. --Mr.98 (talk) 21:03, 2 December 2009 (UTC)

SIGHUP udevd on new USB device

Sometimes when I connect a USB storage device to my ubuntu laptop, udev doesn't acknowledge it nor does it mount manually, even though the device shows up in /dev/disk/by-id just fine. The only way I know of to fix this is to send SIGHUP to udevd. Is there any way I can have a SIGHUP sent automatically when I plug in a USB device? NeonMerlin 12:25, 2 December 2009 (UTC)

A hacky fix (rather than actually fixing whatever is causing your problem) would be to watch /dev/disk/by-id with inotify and SIGHUP whenever that sees a change. inotify has a nice utility which makes it useful from shellscripts - I'd guess you'd just do (in pseudo shellscript) something like:

  while true:
    inotifywait /dev/disk/by-id
    kill -HUP $udev_pid

I can confirm that inotify does indeed work inside /dev. You may benefit from a sleep 1 between the inotifywait and the kill, to make sure the kernel has everything up before forcing udev to look at it. -- Finlay McWalter • Talk 14:31, 2 December 2009 (UTC)

What are normal CPU and motherboard temperatures?

My second-hand old computer has five fans in it, including the CPU fan and the power-unit fan. In other words its got three case fans. It is very noisy. I've disconnected one of the case fans, and I'm wondering if I could disconnect one or two more without harm, to reduce the noise. My previous old computer only had a power-unit fan and a CPU fan as far as I recall, and worked OK. The current temperatures are Motherboard 34 degrees C, CPU 27 or 28 degrees C, HDD 26 degrees C, fanin0 2812rpm, and fanin1 3125rpm. As its winter with the central heating off the room temperature is only 19 degrees C. Are the computer temperatures good? Would disconnecting one or two more case fans be advisable? Thanks 89.242.106.49 (talk) 13:59, 2 December 2009 (UTC)

I'd normally be reluctant to disable fans, but those temps seem quite low. You might also want to consider other noise reduction strategies, like placing the computer in a compartment of a wooden shelf (should be open in the back to allow cooling). If you don't have such a compartment, you could make something like that yourself out of Styrofoam sheets. StuRat (talk) 06:22, 3 December 2009 (UTC)

Many times case fans are the standard 80mm type and are easily replaced with far quieter temperature sensitive versions. Check out your favorite online retailer of computer parts (NewEgg is one in the US that comes to mind) many have a wide variety at a low price. This solution would keep your hardware safe and the ambient noise down. --Jmeden2000 (talk) 21:27, 3 December 2009 (UTC)

What computer systems are bank accounts located on?

I've been wanting to ask this question for a long time. Bank accounts must nowadays physically exist on some sort of computer systems. But what sort? They must be pretty incredibly reliable, otherwise people would get very upset when a computer failure causes them to lose money. How does it actually work? JIP | Talk 20:20, 2 December 2009 (UTC)

Traditionally most would be on mainframes. Eg the IBM mainframe. Graeme Bartlett (talk) 21:04, 2 December 2009 (UTC)

I know that the ATMs for the Nationwide Building Society run XP. I once had one BSOD on me while I was making a withdrawal.--80.176.225.249 (talk) 23:54, 2 December 2009 (UTC)

NCR ATMs all used to run OS/2; I believe a lot of current ones run Windows 2000. -- Finlay McWalter • Talk 00:35, 3 December 2009 (UTC)

I believe many nowadays may use Windows XP editions#Windows XP Embedded not Windows 2k, but I'm not sure. Others may use Windows CE. These things tend to have a long lifecycle so it's difficult to say, Windows XP Embedded or CE or some other version of Windows Embedded (including Vista Embedded) is obviously what Microsoft would suggest [1] but it doesn't mean they're using it. [2] [3] [4] [5]. Windows 2k and even some version of 9x has been used in the past I believe. Nil Einne (talk) 03:35, 3 December 2009 (UTC)

Tandem Computers was a big supplier for bank back-office equipment, because they had a lot of technology for seamless failover. That behaviour was subsequently adopted by the post-mainframe suppliers (IBM, Sun, HP, SGI, and latterly by Microsoft) whose equipment dominates now (using essentially what they sell as internet servers). The traffic volumes really aren't that high (when compared with things like World of Warcraft or Google), and the database is readily shardable. Electronic banking still works, at a procedural level, pretty much like manual banking (with paper ledgers) - there is no need for a constantly consistent global state, as they perform a reconciliation at the close of business. So they have a bunch of logically and physically separate machines doing redundant transaction logging (so they can always replay the day after hours to rebuild a consistent view), and they run multiple failover groups (at multiple geographically distinct sites, with multiple redundant connections between them). While Sun et al hardware is both very reliable and fault-tolerant, the real redundancy comes from having lots of everything, and lots of wires between them all keeping everyone up to date. -- Finlay McWalter • Talk 00:35, 3 December 2009 (UTC)

Whitney National Bank uses IBM's i OS for its core systems - this story has a lot of detail[6]. The National Bank of Greece apparently uses z/OS and OS/390[7] which run on IBM mainframes. If you search IT news sites you'll find a lot of stories about what banks are buying and using. IBM mainframes with IBM operating systems seem very common. --Pleasantman (talk) 12:54, 3 December 2009 (UTC)

Banks in South Africa use a variety of platforms and systems, but the mission critical systems like the transactional ones use Oracle databases on "high availability" / clustered (such as RAC) platforms. The redundancy is either provided by Oracle themselves or vendors such as EMC who provide solutions such as BCV. I know someone at one bank that monitors the national Cisco network on which the ATM's are connected. These things are also redundant and fault tolerant at the core, but when remote points fail then operations people and engineers run around like headless chickens trying to sort them out. HA solutions are normally hosted by companies like IBM. The company I work for has HA systems at an IBM site a few hundred metres underground, so if the entire district is bombed, the company's systems are still operational. Further backups are sent offsite to another location 40 kilometres away "just in case". We have many copies of our core databases on warehouse setups as well, so it's almost impossible to lose data for more than a day. Sandman30s (talk) 10:47, 4 December 2009 (UTC)

PS3 60GB & PS3 slim 120GB hard drive swap.

I have an original 60GB PS3 and a new 120GB PS3 slim. I successfully backed up my 60GB data using the Backup tool in the PS3 System menu to a large USB thumb drive. I swapped hard drives and the old PS3 powered up fine. It said that the drive contained a different system and needed to be wiped. So it wiped the drive and then restored the backup from the thumb drive. The "fat" PS3 works great and I have about 112GB of storage now.

However, when I put the 60GB drive into the PS3 slim, it will start up, but says that it can't find any system files. It asks that I hold down the start and select buttons to restart the system. I do that and it brings me back to the same warning. I thought it would go through the same auto format procedure, but it's isn't. I can't get to the XMB to format the internal drive. Any ideas how to fix? --70.167.58.6 (talk) 22:41, 2 December 2009 (UTC)

I found the answer here [[8]] --70.167.58.6 (talk) 15:52, 3 December 2009 (UTC)