Wikipedia:Reference desk/Archives/Computing/2008 February 12

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[edit] February 12

[edit] PSD to Vector

I made a vector logo in Photoshop for a friend to be printed on a t-shirt. I downloaded a font from DaFont that he does not have. I want to leave him the flexibility of scaling the vector as big as he wants, but Photoshop won't let him do that properly if he does not have the same font that I downloaded. Without him having to download that font, is there anyway I can compile all the layers in Photoshop into a vector and send it to him so that he can re-scale to however large he wants? Thanks. Acceptable (talk) 02:48, 12 February 2008 (UTC)

Not exactly: Keeping the font as a vector (essentially, a bunch of equations) requires the font, which contains that data, so, without out the font, he will need to use a static image. Fireworks may allow you to convert this into a vector anyway, although, I'm not positive. In short, no, he will need the font, because you can't just convert an image into a vector (to my knowledge). Arcoain (talk) 03:10, 12 February 2008 (UTC)

Well, there was Adobe Streamline and you may find Adobe Illustrator still has enough of that capability to do it.
Atlant (talk) 13:07, 12 February 2008 (UTC)
Right-click the text layer(s) and click 'Convert to Shape' — Matt Eason (Talk • Contribs) 20:10, 12 February 2008 (UTC)

[edit] wireless router disk

Hi everybody! Where can I download a "setup disk" for a linksys wireless router (model WRT300N)? I don't have the disk. Thanx everyone! xxx User:Hyper Girl 13:39, 12 February 2008 (UTC)

Have a look here, check your version. For 1.0 and 1.1 the setup wizard is available for download. Tell me if it worked. Cheers, Ouro (blah blah) 14:20, 12 February 2008 (UTC)
Thanks Ouro. It only lists a "Data Sheet" "User Guide" and "GPL Code". I'm version 2. I've also found something called a firmware update, but its in .bin format. Am I supposed to compile these or something? xxx User:Hyper Girl 14:26, 12 February 2008 (UTC)
There's an old Chinese saying: Check your user guide for Upgrade instructions. --Ouro (blah blah) 14:29, 12 February 2008 (UTC)
(I didn't want to be rude - but that's what the release notes for the firmware update say.) --Ouro (blah blah) 14:41, 12 February 2008 (UTC)
Ok, maybe I'm being incredibly naive here. I've got this router a friend gave me. No cables, no disk, just the router. I've got a power adapter with the right volts and ampage (12v 850mA) and the lights come on. Next I connect the router to my PC (win xp sp2) via a network cable and Windows detects it as a "local area network". Now what? How can I use it to connect to other wireless devices? How do I alter the routers SSD and other settings? As far as I can tell I need the setup disk to install the right software to do these things, right? Or am I completely missing something? I really do appreciate your help Ouro. xxx User:Hyper Girl 14:58, 12 February 2008 (UTC)
Well, the router will allow you to connect to other wireless devices, like wireless network cards, in order to construct a local area network. However, anything above what you ask - I do not know, it'd be best you downloaded the user guide (it's available at the link I posted above) and read it. Maybe, just maybe, the router doesn't require any further software for basic functionality (ask your friend whether he ever had any software with it). Most probably you do need appropriate software for it, I've tried Googling for it but didn't find what you were looking for. Do you have another PC with a wireless network card to check whether it's functioning properly? Cheers, Ouro (blah blah) 15:22, 12 February 2008 (UTC)
My friends' (this is a different friend, by the way) laptop detects it as an "unencrypted netword" and can connect to it, but I can't select and conect from the router myself. I'll ask him (the orignal friend) if he needed any extra software to run it. I'll let you know how I get on. xxx User:Hyper Girl 15:30, 12 February 2008 (UTC)
Since it's a Linksys router, the web based administration screens can almost certainly be accessed by using a browser and entering http://192.168.1.1. The factory default for logging in is no username, and password=admin. If those defaults have been changed, you should be able to restore the factory defaults by pressing and holding the reset button for 15 seconds or so. You really shouldn't need any additional software, the setup wizards just automate some of the configuration. --LarryMac | Talk 16:03, 12 February 2008 (UTC)
OMG!! Thank you sooooo much LarryMac! That worked perfectly! —Preceding unsigned comment added by Hyper Girl (talk • contribs) 11:27, 13 February 2008 (UTC)

[edit] Unix Commands

Hi there. I'm trying to do some revision of UNIX, and there's something i'm not sure about, if you had the following command:
echo "My name is Jac" >> temp,
does the temp file have to already exist?, what happens if it doesn't? Thanks--Jac16888 (talk) 14:10, 12 February 2008 (UTC)

Shot in the dark: it gets created. --Ouro (blah blah) 14:20, 12 February 2008 (UTC)
Yes, it will create the file. If the file already exists it will append to it. -- kainaw™ 14:23, 12 February 2008 (UTC)

Well now i feel stupid, thats pretty obvious. I hate all this command line stuff. I do have another question, i created a directory in unix, but when i try and view the permissions, using ls -1 "filename", i get no response, or error message either. What am i doing wrong. Thanks--Jac16888 (talk) 14:54, 12 February 2008 (UTC)

Try ls -l (a lowercase ell, not a one). And you shouldn't need the quotes - just enter the first couple of characters and hit tab to autocomplete. —BradV 15:23, 12 February 2008 (UTC)
Damn, you beat me too it, i just realised my idiotic mistake, l not 1, i knew about quotes thing, was just using them here, not in the command. I'm not always this stupid, honest. Thanks--Jac16888 (talk) 15:25, 12 February 2008 (UTC)
Remember, when you ask for a listing and specifically mention "dirname", you'll get the contents of that directory rather than information about the directory itself. And if you just created the directory, then the contents of that directory is empty -- hence; "no response". You want "ls -ld" to show the status of the directory itself rather than the status of its contained files.
Atlant (talk) 17:44, 12 February 2008 (UTC)
Ah, we learn something every day! I didn't know about ls -d. —Tamfang (talk) 05:32, 19 February 2008 (UTC)
I came from an environment where this sort of thing wasn't true so I've always felt that the need for "-d" was misfeature of Unix. Instead, I'd have designed it so that without the final slash on the path (e.g., foo/bar), it would give you the status of the directory bar itself but with the final slash (e.g., foo/bar/), it would give you the lasting of the contents of the directory bar. But obviously, someone else felt differently for long enough that this misfeature became standard practice and they invented "-d" to cover this case.
Atlant (talk) 18:56, 19 February 2008 (UTC)

[edit] Annoying virus, perhaps rootkit

Hi all, I think I might have some sort of virus/rootkit that is annoying me. I am running xp pro and Avast anti virus keeps identifying a file called ndt2.sys in my system32 folder as being a Trojan horse. It alerts me about once or twice a day and then promptly deletes it. I've tried running boot time scans which revealed some things, which were deleted, but this one still came back. As far as I can tell, avast manages to stop it before it does anything. I've googled it but can't find anything conclusive as to what it is or how to get rid of it. Any help you guys can give would be greatly appreciated. Z28boy (talk) 17:56, 12 February 2008 (UTC)

If you have a 32 bit processor, you might want to try [1]. Hope that helps. However, if you are privacy concerned, please be prepared to wipe your hard disk clean. (Hint: up to date back ups of documents and stuff) Kushalt 18:20, 12 February 2008 (UTC)
AVG anti-rootkit just requires a 32-bit XP or Win2k installation, not a 32-bit CPU. There are also many alternative scanners. At the latter point though, I also would not trust any Windows install that's been compromised by something like this. I'd definitely suggest cleaning the HDD; if you don't want to clear the whole thing out, just use a Linux or Windows LiveCD and wipe the Windows directory, and everything that's executable (.exe, .dll, .ocx, .sys, .scr). -- Consumed Crustacean (talk) 21:35, 12 February 2008 (UTC)

I was anticipating this to come. If it is not very inconvenient, the best way would be to back up original documents (and other irreplaceable data) and do a complete Hard Disk format. Do you still have your bootable Windows XP installation CD? Kushalt 22:14, 12 February 2008 (UTC)

Yes I do still have the original disk, but I will have to buy an external hard drive to back my stuff up, which I've been meaning to do anyways. I'm going to give these cleaners a try and see how they work and then go from there. Thanks for the help. Z28boy (talk) 23:56, 12 February 2008 (UTC)

Remember to install Service pack two and a good antivirus program as soon as possible after reinstalling, though. When I had Windows, I used AVG Free Antivirus. ClamWin does not have real-time scanning but it seems to be in the making. I recommend AVG because it was very easy for me to uninstall, as opposed to a very reputable antivirus package. Well, I guess I am rambling too much. I am sure you know better. Good luck.

Regards,

Kushalt 18:07, 13 February 2008 (UTC)

[edit] comparison of MediaWiki vs Drupal-Wiki

Greetings all,

Anyone have specific hands-on experience using a Drupal-based wiki? If so, do you have any comparision of that vs MediaWiki? I am very familiar with the way MediaWiki works (having used Wikipedia), but I do not know how Drupal stacks up, or whether there even is a robust wiki module for Drupal.

Also, if you have any links with detailed side-by-side comparisons of Wiki software, specifically including (but not limited to) the two mentioned above, that would rock.

Thanks. NoClutter (talk) 18:41, 12 February 2008 (UTC)

Does http://en.wikipedia.org/wiki/Comparison_of_Wiki_software Comparison of Wiki software fit the bill? Kushalt 19:39, 12 February 2008 (UTC)

Nope. That's why I asked for "specific hands-on experience" because those comparison lists don't give anything but a superficial overview that can be written by anyone whose just read the documentation without actually having tried the software. Also, you'll notice that the article you linked doesn't even mention Drupal. NoClutter (talk) 20:16, 12 February 2008 (UTC)

I am sorry for the inconvenience, NoClutter. Kushalt 22:08, 12 February 2008 (UTC)

[edit] Windows 3.1

I am curious, would Windows 3.1 run at 1680x1050? Dr Alcohol (talk) 20:26, 12 February 2008 (UTC)

If you can find drivers that'll handle that resolution. --Carnildo (talk) 20:57, 12 February 2008 (UTC)
Drivers for Windows 3.1, no less. Good luck on that one. PulseXS (talk) 21:15, 12 February 2008 (UTC)
You have a copy of Windows 3.1? I'm jealous. I have the install disks for DOS 6.1.1, though. I'm only running XP at 1024x768 and you want to run 3.1 at 1680x1050, I'm stunned. Useight (talk) 23:52, 12 February 2008 (UTC)
I found this page [2] xxx User:Hyper Girl 13:58, 14 February 2008 (UTC)
None of those look too useful: the SVGA drivers probably won't support anything larger than 640x480x256 (and maybe 800x600x16), and the other video drivers are specific to obsolete graphics cards. Your best bet is to search for generic VESA drivers. --Carnildo (talk) 21:29, 14 February 2008 (UTC)

[edit] Unix filesystem question

Is it somehow possible, in Unix, to share a directory across several physical filesystems, so that when a file is written into the directory, the OS would somehow automatically select which physical filesystem it is stored in? JIP | Talk 20:36, 12 February 2008 (UTC)

Most modern implementations will let you create a single filesystem that uses more than one physical disk. But I can't tell whether this is what you're asking, exactly. Friday (talk) 20:42, 12 February 2008 (UTC)
No, this is not quite what I mean. If I have already partitioned a physical disk into several partitions, each with its own filesystem, can I later add a directory that span several of them? For example, if the disk /dev/sda has partitions /dev/sda1, /dev/sda2, /dev/sda3, and /dev/sda4, can I create a directory /home that spans both /dev/sda2 and /dev/sda3? Can this be done "hot", meaning that creating or deleting such directories does not damage any other data on the filesystems? JIP | Talk 20:57, 12 February 2008 (UTC)
You want to aggregate your physical devices together into one logical device? This is common these days, but now we're back to what I was originally trying to say. It's not going to let you re-mount a physical device that's already mounted. If /dev/sda1 is mounted on /usr, for example, you can't also do something else with it. I don't think what you're wanting is going to be doable. But, it's possible that some fancy volume management tool could do tricks like this. Altho.. you could always mount /dev/sda2 on /home/something and /dev/sda3 on /home/somethingelse, and now "/home" does span two devices.. But I don't think this is what you had in mind? Friday (talk) 21:14, 12 February 2008 (UTC)
What I want, is to be able to have a directory /home (not necessarily a mount point by itself) that somehow appears on two filesystems put together, say /dev/sda2 and /dev/sda3. So when I write a file /home/foobar.txt, the system can put it into the /dev/sda2 filesystem or the /dev/sda3 one as it pleases, completely transparent from me. I don't even have to specify any subdirectory. The directory /home need not be a real directory, it can be some sort of symbolic link. I don't think this is possible, but I want to ask anyway if it somehow would be. JIP | Talk 07:18, 14 February 2008 (UTC)
In case that's not clear.. just remember, in unix you have a logically monolithic file system- you can just think in terms of directories and files, without ever having to care about physical disks. Contrast with Windows which wants a different drive letter for different devices. If you have a device mounted on /home, you can unmount it and stick on on /something/completely/different, and now all those same files are now there. Not sure if this helps.. Friday (talk) 21:21, 12 February 2008 (UTC)
You can mount an NTFS volume on another NTFS volume since Windows 2000 and I believe earlier. Nil Einne (talk) 17:25, 13 February 2008 (UTC)
Union filesystem --tcsetattr (talk / contribs) 22:35, 12 February 2008 (UTC)

[edit] RPM of Flash harddrive

Even though Flash solid-state storage devices have no moving parts and obviously no rotation, how do their retrieval and write speeds compare to traditional magnetic hard drives measured in RPM's? What would be a close approximation of their speed in RPM's? Acceptable (talk) 22:30, 12 February 2008 (UTC)

Uh what. There is no comparison, they work entirely differently. Much faster though :D\=< (talk) 22:49, 12 February 2008 (UTC)
You should take a look at reviews such as this. In particular, they are faster for some operations, but hopelessly slower for others (random writes). Thus the comparison depends on your application, but overall I'd say a typical SSD is a match for a 10k magnetic drive. -- Meni Rosenfeld (talk) 23:16, 12 February 2008 (UTC)
The RPM of a drive measures how long the drive must wait until the correct bits are under the head. The seek time of a drive measures how long the drive must wait until the head has moved to the correct track. For solid state storage, the comparable metrics might be the device's Wait state -- generally, the time it takes for the memory's bits to settle into a stable state and push a byte back. I've never seen wait states shown for flash devices -- only DRAM. In general, though, Meni has it right -- reading from flash is generally stupidly fast. Writing, though, is much more difficult, because you usually have to read in the whole block, make your changes, then write out the whole block. This is on top of the additional time it takes to 'burn' when you're writing to flash. --Mdwyer (talk) 23:27, 12 February 2008 (UTC)
I don't think sector writes work that way. Flash bits have to be erased (set to 1, say) in big chunks, but they can be flipped the other way (1 to 0) in much smaller chunks. Flash drives that mimic hard drives store a sector to a new location each time it's written (for wear-leveling purposes), so as long as there's some space left in a previously erased block, writing a sector only requires writing to the corresponding flash page (plus updating the sector mapping information). The only case where you'd have to do a read-modify-write would be when the sector remapping has become fragmented to the point where there are no empty blocks available for reuse. -- BenRG (talk) 14:50, 13 February 2008 (UTC)
I don't know about common SSDs, but USB keys and flash memory cards are often slower in both reads and writes then the fastest hard disks (and not just because of interface limitations). They do however have much better random access times as has been mentioned several times already. However it would be easy to achieve better read and write times then HDs by using several flash memory chips in a internal RAID0 style array SSD, I just don't know if it's done. Finally bear in mind the RPM only has very limited meaning when it comes to measuring the speed of a hard disk. Seagate 7200.11 with its 250gb platters can achieve 100MB/s sequential read speeds and indeed rivals the 10k RPM WD Raptors I believe. A Seagate 7200.7 is a LOT slower. Both of these are 7200RPM disks. N.B. But don't assume sequential transfer speed is all that matters. Seek times do too, and WD Raptors win on those. So does caching, not just cache size but caching performance. In reality, measuring real world performance of a disk is notoriously difficult and it depends very, very greatly on the OS, application, fragmentation level etc of the disk. The only website which I have come across that does a resonably good job of it is Storagereview.com. Anyone who does some simple test and tells you disk 1 is better then disk 2 doesn't know what they're talking about and should probably be ignored. There is no simple metric to compare disk performance because there are so many things that can vary. Nil Einne (talk) 17:21, 13 February 2008 (UTC)
On the one hand, everything you said is right. On the other hand, wtf are you talking about, SSD hard drives are much faster :D\=< (talk) 21:17, 13 February 2008 (UTC)
That's what they want you to think :). Seriously, that's just wrong. Somebody probably did some simple test and told you that SSDs are better than HDDs. -- Meni Rosenfeld (talk) 22:20, 13 February 2008 (UTC)