Wikipedia:Reference desk/Archives/Computing/2009 March 4

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March 4[edit]

Drive overclocking[edit]

My question is as follows: is it possible to override a locked system setup and overclock a drive? If so, is there a program i can use, or a file i can edit, ect. —Preceding unsigned comment added by 99.7.3.15 (talk) 03:50, 4 March 2009 (UTC)[reply]

Header added — Matt Eason (Talk &#149; Contribs) 10:13, 4 March 2009 (UTC)[reply]
I'm not really sure what you're asking. Overclocking usually means increasing the frequency of CPUs or GPUs (or memory, etc). It doesn't apply to disk drives. You can sometimes increase the performance of a drive by adjusting some parameters in the OS (see hdparm), but AFAIK it's not realistically possible to increase the physical operating speed of a hard drive (its RPMs, for instance). Did that answer your question? Indeterminate (talk) 22:32, 4 March 2009 (UTC)[reply]
I doubt there are any hard drive controllers or motherboards which have the capability to alter the hard-disk mechanical speed; it seems plausible that one could overclock the IDE or SATA bus, but I have never heard of this in practice... Nimur (talk) 16:42, 5 March 2009 (UTC)[reply]

Can I uninstall Microsoft Visual C++ 2005 after I have installed Visual C++ 2008?[edit]

I see both in my list of installed programs and am not sure if they are redundant. Will redundancy cause any problems? Can I uninstall Microsoft Visual C++ 2005? —Preceding unsigned comment added by 117.0.22.167 (talk) 06:03, 4 March 2009 (UTC)[reply]

Sure. I suppose if the newer program has been very badly designed, it might stop working, but even if that's the case, you can just reinstall it. -- Captain Disdain (talk) 09:23, 4 March 2009 (UTC)[reply]

electroni signature[edit]

Is there any electronic signature software that supports Open Office format that you know of?

If yes, can you please provide me with the relevant company or software that can help me. —Preceding unsigned comment added by Thembanim (talkcontribs) 11:42, 4 March 2009 (UTC)[reply]

GPG will do it (it can sign any file; the format doesn't matter). --Aseld talk 12:09, 4 March 2009 (UTC)[reply]

what is computer?[edit]

i learn that computer is a multipurpose machine, —Preceding unsigned comment added by Tselisehang (talkcontribs) 14:14, 4 March 2009 (UTC)[reply]

Does our article computer help? Algebraist 14:16, 4 March 2009 (UTC)[reply]
My personal definition is: "A computer is a machine for following rules." - but our Computer article covers the ground quite nicely. SteveBaker (talk) 18:40, 7 March 2009 (UTC)[reply]

What is Windows Media Format Runtime?[edit]

it is in the Add/Remove programs —Preceding unsigned comment added by 117.0.7.67 (talk) 16:36, 4 March 2009 (UTC)[reply]

As far as I am aware it is an add on that it is required for WMA (Windows Media Audio) and WMV (Windows Media Video). BigDuncTalk 18:59, 4 March 2009 (UTC)[reply]

Virus infection[edit]

How long would an unprotected PC last on the net without any kind of protection at all before it was infected with a virus BigDuncTalk 19:58, 4 March 2009 (UTC)[reply]

Well, that would depend entirely on what sites you visited. Tracking cookie - 2 clicks, virus/malware- (depending on which sites), maybe an hour or so. DoS? .. tough to tell, a lot would depend on your visibility (web-sites, where your email was posted, etc.) - maybe a couple days if you avoided porn, shareware, hacker sites, shopping areas, etc. In other words? Depends on what you do on the "net". — Ched ~ (yes?) 20:07, 4 March 2009 (UTC)[reply]
Times for Windows XP machines have been given at 20 minutes [1] and 40 minutes [2]. That's just sitting there, not going to all those things Ched describes. Those numbers date from 2004/5; I haven't seen reliable times for Vista machines. 87.113.106.21 (talk) 20:42, 4 March 2009 (UTC)[reply]
Also depends on the OS. There aren't so many viruses floating about for older or less common operating systems. I ran an old Win95 for ages without virus software and it was fine. —Preceding unsigned comment added by 82.43.88.87 (talk) 20:54, 4 March 2009 (UTC)[reply]
Windows 95? Good heavens - that fella deserves a seat at the head of the table as an honored Senior Citizen ... LOL — Ched ~ (yes?) 21:03, 4 March 2009 (UTC)[reply]
Well, I know dozens of people who haven't been bitten yet. Maybe, just maybe, that's because they had a professional set up their machines, don't run as admin, and don't do porn/shareware/ish stuff. Who knows? ;) -- Fullstop (talk) 22:01, 4 March 2009 (UTC)[reply]
I suspect a (properly configured) home router helps significantly; if worms cannot get to a computer they have trouble infecting it. – 74  22:09, 4 March 2009 (UTC)[reply]
Twenty minutes sounds to be about what I have heard for a Windows XP machine connected to the Internet without any service packs or virus protection installed. Useight (talk) 02:48, 5 March 2009 (UTC)[reply]
With an old copy of Windows XP (Gold, no Service Packs), I went online with 56K dial-up (!!) and got Blaster within four minutes of being online (luckily I knew 'shutdown -a' at the time). Taught me to re-install XP and forget to also install my firewall-of-choice (with a CD-saved installer) before going online. This would have been roughly the time a little before SP2 came out, and was well before I started slipstreaming everything. Also, yes, I was able to recover the install for a short time before re-installing once more. (Washii) 63.135.50.87 (talk) 06:29, 8 March 2009 (UTC)[reply]

C++[edit]

What is the point of having all of the different things in C++? There are templates, namespaces, classes, and probably other things I don't know about. What is the function of one of these compared to the others? Ζρς ιβ' ¡hábleme! 21:23, 4 March 2009 (UTC)[reply]

Each function will have a slightly separate way of working, or will exist because they are in use by a sector of people who would prefer that 2 otherwise identical functions remain separate. Coding is like hand-writing, whilst we might all write the same language everybody has their own style and way of developing. Here is a discussion around Classes V Namespaces for example (http://www.velocityreviews.com/forums/t456911-class-vs-namespace.html). ny156uk (talk) 22:28, 4 March 2009 (UTC)[reply]
Namespaces: otherwise every global name gets thrown into one big pool; in languages like C, without namespaces, you run the risk that you (or one of your colleagues, or one of the myriad of authors of libraries you're using) will coincidentally use the same name as you do, and you'll accidentally refer to the wrong thing. If you're lucky you'll get a type incompatibility error when compiling; if you're not, you'll end up calling the wrong get_count() or whatever, which can be a very unpleasant problem to find and fix. So namespaces are a good thing. Large C projects, and C libraries, often have to adopt a strict naming policy for globally available names (e.g. you're writing the "transaction" module, so all your functions have to be called txn_foo() or whatever. 87.113.106.21 (talk) 22:34, 4 March 2009 (UTC)[reply]
Classes: well, that's the core bit that enables object oriented programming. You can do object oriented programming in languages that have no native support for it (I've lost count of the number of object systems I've seen implemented in C) but doing so makes for rather harder to follow code, requires discipline that's hard to keep up, and can be a bit fragile. If you don't want to do object-oriented programming, you just don't bother with classes. 87.113.106.21 (talk) 22:38, 4 March 2009 (UTC)[reply]
Templates: templates enable generic programming. That is, say you write code for a linked list of integers. But then you need a linked list of strings, and a linked list of floats, and a linked list of some complex struct. With templates you just write a linked list of <anyoldthing>, which means you've only had to write the linked list part once (for complex data structures that can be a big deal). Now, again, you can do this without templates and generics; in C you'd just have a linked list of void *, but that imposes the burden of casting things to the correct type on the caller; worse, that cast breaks type safety - so you can mess up and put a bunch of ints into a list, but then the code that pulls them out thinks they're something else entirely, and blithely casts the value it gets to the wrong type, which means what comes out is hopelessly garbled and wrong. Try that with templates and you'll get a compile time error (compile time errors are good; run time errors are bad, especially when your runtime is a mars rover or a nuclear missile). Templates give you the advantage of writing a general purpose thing once, but without the disadvantage of having to throw away type information. 87.113.106.21 (talk) 22:44, 4 March 2009 (UTC)[reply]
In short, you don't need any of the features that C++ adds to C; indeed, you can do anything in C if you really want: functional programming, lazy evaluation, exceptions, coroutines, tail recursion, objection orientation and inheritance, automatic memory management, generic programming, etc. But you end up with a bunch of scary macros and fragile cruft and some really strict rules for using them (rules that the compiler won't enforce). Frankly that scary stuff is all still there in C++, but you can mostly forget about it. Mostly. 87.113.106.21 (talk) 23:03, 4 March 2009 (UTC)[reply]
Other posters explained the specific features pretty well. I'll add that the basic point of C++ is to help keep very large projects (with a lot of programmers who come and go and who aren't necessarily familiar with the whole code base) from getting disorganized. All the weird tensions and trade-offs in C++ were driven from experiences in such projects. If you're new to programming or mostly working on small or solo projects, it's not a good language to start with. 13:26, 5 March 2009 (UTC) —Preceding unsigned comment added by 207.241.239.70 (talk)

Putting Two .jpg Files Into A Single .pdf[edit]

I made a nice looking document on MS Word 2007, with some gradients to make it look nicer, then when I exported to .pdf, I ended up with a .pdf file with stripes all over it, instead of a two gradients. Anyway, I decided to take the original .docx and (with no gradient) and export them to .pdf, then edit them with GIMP, giving me the effect I wanted. Unfortunately, GIMP will only edit one page at a time (it seems - as when I click the option to edit both, it adds them both as layers, which is not what I want). So, now I have two beautiful .jpg pages, but they are separate files. Now, my question is, how can I combine them as a single .pdf file, i.e. with two pages? I don't want to put them both back into a Word file as inserted images, as they will be smaller (because of the page margin, which is of course already included on the new .jpg files). Anyone have any ideas here?--KageTora (talk) 23:08, 4 March 2009 (UTC)[reply]

A simple Google search returned PDF Split and Merge. – 74  23:17, 4 March 2009 (UTC)[reply]
Thanks. That's part of the battle. Now I need a .jpg > .pdf converter, as that software won't do anything unless it's .pdf files I am dealing with.--KageTora (talk) 23:30, 4 March 2009 (UTC)[reply]
A PDF printer, e.g. PDFCreator, will take care of that. --Andreas Rejbrand (talk) 23:56, 4 March 2009 (UTC)[reply]
[Answer for the next question below - Wikipedia seems to have gone haywire again] Thanks, folks. That all worked.--KageTora (talk) 00:14, 5 March 2009 (UTC) (comment moved to "question below" – 74  03:12, 5 March 2009 (UTC))[reply]