Wikipedia:Reference desk/Archives/Computing/2006 November 28

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[edit] November 28

[edit] Free software licenses

This might sound dumb, but if software is really completely free and open source (like Linux), what is the purpose of even including a statement about the legalities of reproducing/editing/selling etc the software?

Robin

The father says to the young man dating his daughter, "You may take her to the concert, but I expect her home by midnight." (Having been a young man himself once, he knows the other limits he would like to set would be futile.)
As metaphor, this is the job of a software licence. If, for example, an unethical company renames the software and sells it as its own creation, there is a legal remedy to make them stop. --KSmrqT 01:20, 28 November 2006 (UTC)
Pretty much. Look at the definition of free software. "Free" has a very specific meaning here in respects to copyright. It does not mean "public domain". --24.147.86.187 03:41, 28 November 2006 (UTC)
Totally free as in freedom licenses do let you just take the product and sell it outright - but you'd have to be pretty dull witted to buy a free-of-charge product. Isn't that what linspire did? --frothT C 04:40, 28 November 2006 (UTC)
It's free software, not open-source. Open-source is more like a business strategy which goes, "Trust us! We release our source code! We benefit because everyone likes the term 'open-source'!", while free software is more like, "We give our source code away for your benefit, not ours." --wj32 talk | contribs 09:31, 28 November 2006 (UTC)
Open-source isn't that negative- for many companies profitability is a big concern and they can't afford just to give away their code. All the same, they don't mind it being worked on by the OSS community --frothT C 16:49, 28 November 2006 (UTC)
If we are going to delve into finer distinctions, consider a novel. It is completely open; anyone can read any page. In fact, that is the intent! However, that does not give others the right to plagiarize chapters, nor to print and sell copies, nor to post a copy on the Web.
Or, consider an iPod shuffle. Apple Computer might be willing to give one away as a promotion. However, if you "borrow" its technological innovations or try to sell an identical product, be prepared to meet some stern lawyers.
The same considerations apply to software. It can be open-source (like a novel), and/or it can be free-of-charge (like the promotional iPod). But that does not mean the creators wish to relinquish all rights. A license is a standard way to state what rights are granted, and what rights are reserved. Here is an analysis that goes into more detail. --KSmrqT 22:59, 28 November 2006 (UTC)
Most licenses for open source software, notably the GNU GPL, stipulate that you may charge for the transfer of your software, but that you must have access to all source. Further, derivatives of the software must also be under the GPL, as well. This protects developers from having companies commercialize their open-source ventures. 134.129.60.126 03:40, 30 November 2006 (UTC)

[edit] FTP program

How do you setup a bat file to run an FTP script, with username and passwords, getting the files and changing directories

wget for Win32 will fetch files from the command line, and will work in batch scripts. Droud 12:30, 28 November 2006 (UTC)
I believe the user is asking for a scriptable FTP client. Unfortunetly, I know none. ☢ Ҡi∊ff⌇↯ 23:50, 29 November 2006 (UTC)
On Unix, ftp itself is, kinda, scriptable - http://www.mcwalter.org/technology/shell/ftp.html I don't think the cmd.exe is flexible enough to allow this, but perhaps Monad is? -- Finlay McWalter | Talk 10:07, 30 November 2006 (UTC)
The Windows command-line ftp is scriptable. You use ftp -s:filename where filename is a text file with commands you would normally enter at the ftp prompts. Bavi H 05:57, 3 December 2006 (UTC)

[edit] Problem with my mouse

I'm using Windows XP Pro, 2002. My mouse has a wheel, but when I turn it, nothing happens. When I go to the Mouse properties in Control Panel, there is no Wheel tab, although the documentation suggests there ought to be. Any ideas as to how I might get my wheel to operate? Many thanks. --Richardrj talk email 13:29, 28 November 2006 (UTC)

You probably have to install the software (drivers, that is) for your mouse so that all of its functions would be supported. They most probably came with the mouse, or can be found online if you know the model of the mouse. –mysid☎ 14:07, 28 November 2006 (UTC)
Agreed; the generic mouse driver you are using supports the mouse buttons, but not the wheel. StuRat 00:48, 29 November 2006 (UTC)

[edit] Javascript help

I am working on an in site Search engine for a global project. i uploaded the script, and being of slight nowlage of javascript, added some code to it. only now the part i added doesn't work... help?

please don't copy long blocks of code to the reference desk. by the way, javascript isn't the best choice for a search engine. And it would be nice to know which part you added --frothT C 16:47, 28 November 2006 (UTC)

"nowlage" = "knowledge", in case anyone needs a translation. StuRat 00:42, 29 November 2006 (UTC)

Haha very funny. you know what i ment.Is it Steak?<Xiaden's Homepage> 14:44, 29 November 2006 (UTC)

oh, and srry. won't do it again...

[edit] Direct memory access

DMA seems like a bad idea to me. How would the CPU know when the memory is being updated so it doesn't try to read off that range until it's done? Why not just have a dedicated component on the CPU for data throughput that shares the CPU clock and makes the appropriate information available to memory protection in the OS? --frothT C 17:25, 28 November 2006 (UTC)

Read simultaneous with write is prevented by an interlock in the memory controller. The memory controller is a dedicated device which does the job - clocking it with the CPU would be stupid, as memory is clocked hundreds of times slower than the CPU. Remember that in a modern computer the CPU core isn't directly connected to the memory (only to the cache): it's the memory controller which does the heavy lifting (mostly reading and writing cache pages between the cache and the main memory). A DMA writes to system memory, and the CPU core will know nothing about it unless it asks the memory controller to fetch that section of RAM. Now you'll probably ask "what happens if the DMAed page is in the cache?" - the answer is that the processor's TLB/GDT has a "noncachable" flag, which means the memory controller will always fetch the RAM page fresh when the core asks to read from that page (which, unsurprisingly, is exceptionally slow). Device drivers which manage a DMA capable device are responsible for establishing a noncached TLB entry which corresponds with the DMA settings with which they've just configured the DMA capable device. Now you'll ask "what happens if the CPU is having the memory controller fetch from the DMA space" - the answer is that the DMA capable device must wait (and yes, this risks dropping data if the DMA doesn't complete promptly, but the system is designed so that doesn't happen). And now you'll ask "what if the CPU reads some data, and then decides it wants more - won't the data have been overwritten by another DMA in the meantime - the answer is that the DMA-capable device (and the device driver) between them maintain a circular buffer in the DMA space. -- Finlay McWalter | Talk 18:21, 28 November 2006 (UTC)
Wow, believe it or not I thought exactly those objections to your initial statement heh thanks --frothT C 20:17, 28 November 2006 (UTC)

[edit] XP error reports

Is there any point in "sending" them? With vista done, is anyone still sorting through all that data? What was ever done with it? --frothT C 17:53, 28 November 2006 (UTC)

Well officially Microsoft uses the data from the error reports to further develop their software and find bugs and such things. Inofficially some people might say that they use the data for Data Mining, because usually the error message includes detailed stuff about your hardware, etc. What really happens to the data, only the Devil knows... Aetherfukz 17:59, 28 November 2006 (UTC)

[edit] Way to boost graphics and resolution?

In working on this computer I have yet to get the resolution to be bearable. It is at 640*480 with 16 colors. In the settings box, I can choose all the way up to 16bit High Color, and up to 1024*768. However, upon application of these settings, oth revert down to the lowest possible for this computer. Is there any way I can boost graphics on this thing? Im running 98SE, my graphics card is a Matrox MGA-G100 AGP, the driver is version 4.11.01.1520.

Omnipotence407 18:12, 28 November 2006 (UTC)

Sorry, what does 'oth revert' mean? It seems like such a small component of your post but it has me stumped. Does it revert straight away, without even seeming to attempt the higher resolution? Or does it go higher for a moment and then revert? It sounds like a driver problem, have you tried setting it to 800x600 first to see if that works? Vespine 22:07, 28 November 2006 (UTC)
I speak RefDeskia, so allow me to translate: "oth" = "both", in English. StuRat 00:33, 29 November 2006 (UTC)
Also, with such a dated system, verify that your monitor can support the intended resolutions and refresh rates. Some older monitors will only do 1024x768 at 60hz. Droud 22:48, 28 November 2006 (UTC)
From what I can find, your card will support max 256 colour (8 bit) graphics, at resolutions of 640x480, 1024x768, 800x600, and 1280x1024. So you should be able to get better resolution, but not more colours. It is strange that you are given the higher colour options. The latest driver for win98 at the Matrox site seems to be 5.52.015, dated 25feb2000, while Soft32 has version 5.0.2144.1 (1999). Those cards were >$110 when they came out! Hope this helps. Seejyb 23:29, 28 November 2006 (UTC)
Some older drivers don't restrict that - I was able to stretch my old 14" monitor to, I think, 1280x1024x16. Windows then crashed and I had to find my old floppy disks for my drivers to reset it.  :( I do suspect you do have a driver problem: Windows 98 defaults itself to 640x480x256 if it has a problem and 640x480x16 if the problem is more serious... x42bn6 Talk 00:07, 29 November 2006 (UTC)
I think spending a few bucks on literally the cheapest AGP graphics card you can find will solve all of your problems. Sockatume 22:14, 30 November 2006 (UTC)

[edit] SAM policy change

I read that in order to dump SAM hashes, the hive file has to be modified. Is this true and how is it modified? The wikipedia article on SAM is awful --frothT C 23:04, 28 November 2006 (UTC)