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Submission + - How to take advantage of multi-core or multi-processor programming?

An anonymous reader writes: I have some backgrounds on simple C-programming on Linux platform, and I would like to expand my knowledge by learning how write a code that take advantage multi-processors/cores.

Consider this simple/simplified example: Say I have 8 sets of data, and I simply I want write a program that adds all the member of each set, and add those 8 sums to get the grand total.

I am as a novice programmer could easily implement this using a couple loops, but if, say, the dataset are scaled up gazillion times, how do I take advantage of the multi-processor/cores system to improve the performance?

So the specific questions are:

1. In Linux, is there a way to write the program so that one core calculate first 4 sets, and the other core calculate the second 4 sets? Is there C-libraries like pthread or something like that for this purpose?
2. ,Who makes decision/at which level the decision make as far as which program running on which/how many processors? The OS? Or the way the code compiled?

Comment Re: This subject is work. (Score 1) 241

It's also about people like nurses that travel to visit patients in their homes, who are being paid a salary for the hours they work, but in some cases not for the hours spent travelling to the first patient and from the last patient. If the company is not paying for the time spent travelling to the first job and from the last, there's no incentive to optimise the routes so they start/finish close to home.

Submission + - Ask Slashdot: How to handle unfixed Linux accessibility bugs?

dotancohen writes: It is commonly said that open source software is preferable because if you need something changed, you can change it yourself. Well, I am not an Xorg developer and I cannot maintain a separate Xorg fork. Xorg version 1.13.1 introduced a bug which breaks the "Sticky Keys" accessibility option. Thus, handicapped users who rely on the feature cannot use Xorg-based systems with the affected versions and are stuck on older software versions. Though all pre-bug Linux distros are soon scheduled for retirement, there seems to be no fix in sight. Should disabled users stick with outdated, vulnerable, and unsupported Linux distros or should we move to OS-X / Windows? The prospect of changing my OS, applications, and practices due to such an ostensibly small issue is frightening.

Note that we are not discussing "I don't like change" but rather "this unintentional change is incompatible with my physical disability". Thus this is not a case of every change breaks someone's workflow.

Submission + - Mozilla Scraps Firefox For Windows 8 Citing Low Adoption of Metro

An anonymous reader writes: Mozilla today announced it is abandoning the Metro version of its Firefox browser, before the first release for Windows 8 even sees the light of day. Firefox Vice President Johnathan Nightingale ordered the company’s engineering leads and release managers to halt development earlier this week, saying that shipping a 1.0 version "would be a mistake." Mozilla says it simply does not have the resources nor the scale of its competitors, and it has to pick its battles. The Metro platform (which has since been renamed to Modern UI, but many prefer the older name) simply doesn’t help the organization achieve its mission as well as other platforms Firefox is available for: Windows, Mac, Linux, and Android.

Comment Re:Are there non-malicious uses? (Score 1) 167

Relatedly, I believe the reason that Word is being used as the exploit vector on Windows is because it doesn't have the sandboxing of IE/Firefox/Chrome. While you could get a lot more people to run the Windows attack code if you posted it on websites, it doesn't do any good when every popular browser newer than IE6 is locked down to not be able to launch arbitrary programs or write to most of the filesystem or registry.

Actually from Office 2010 onwards it does have a sandboxed mode which is triggered based on the origin of the document:

Incidentally I'm not sure Firefox has a sandbox as such at least on Windows - e.g. it doesn't run as a low integrity process like IE.

Submission + - Google's assault on Windows Phone continues with a block on maps ( 3

ItsIllak writes: Reports started coming in last night that Google have targeted the users of Windows Phone devices and begun to deny access to their maps in-browser service on the increasingly popular mobile devices. On the back of their recent withdrawal of Exchange Activesync from Google Apps, the announcement that they would not be writing their apps for the platform, and several other decisions this brings into question the company's "Do No Evil" motto when it comes to users who choose competitors systems.

Comment Re:Being distracted while driving is dangerous. (Score 1) 217

I expect the type of crash and outcome is quite different between those cases. A distracted/texting driver is probably more likely to end up going full speed into who/whatever they hit without even any attempt to take evasive action, because they're distracted in the first place.

I'd expect in general the turn signal crashes are much less severe, e.g. one car running into the back of another when the first one slowed to turn off without signalling, even if their might be more of these type of accidents.

Comment Re:How about replacing an open file? (Score 2) 456

I don't want to have to install a stupid unlocker program like I do on Windows.

Using such a program has a very good chance of causing random file corruption:

"Forcing a handle closed is equivalent to reaching into a program and freeing some memory. The program thinks the handle (or memory) is still valid and will continue to use it. But since the handle is really free, it will be reused for something else."


Flight Attendant Quits And Exits Plane Via Emergency Slide 24

You may question his actions, but you can't say that 38-year-old flight attendant Steven Slater doesn't know how to quit in style. After a passenger refused to apologize for hitting him in the head with either a bag or the overhead compartment, Slater got on the the loudspeaker and told those aboard to "go f*** themselves." He the grabbed a couple beers from the drink cart, activated the emergency chute, and slid away into unemployment.

Comment Re:walled garden version for the rest of us? (Score 1) 75

Haven't they already taken the first step with compulsory driver signing in their 64-bit OSes?

IIRC, one of the reasons for requiring driver signing was not for the logo certification part (which I thought remained optional, but I may be wrong on that) but actually to help with Microsoft's crash analysis efforts.

With a signed driver it's much easier to identify the vendor of a buggy driver, get in contact and ask them to fix their code, and even offer to push out an update via the Microsoft Update tool.


Submission + - Personal data left in Excel sheet on web server

Alex Dekker writes: "The UK's National Health Service IT program [the catchily-named 'NPfIT'] has come under fire recently for horrific cost overruns [£12.4 billion and counting] and massive under-performance. Not satisfied with that however, they've decided to leave an Excel sheet with large amounts of personal data in a publically accessible directory on a web server. Given that this was on the day that the man in charge of NPfIT, Richard Granger, told the Commons Health Select Committee that "no system can be 100% secure", one wonders if his minions took this as a direct order"

Submission + - How Does One Combat Spam?

An anonymous reader writes: Hey Slashdot crowd, I was curious if anyone has any suggestions on offensively dealing with spam. For a couple years I've been fairly lucky — I haven't really been smacked with spam, maybe one spam e-mail a day or so — but recently I've been getting up to 50 junk e-mails per day on most of my addresses. I don't want to change my e-mail address nor my personal domain because of these idiots, so that's out of the question. My e-mail client does a decent job of cleaning it up and putting it in the Junk mail folder, but are there any offensive measures you guys take against a spammer?

Is there any organization or some sort of united front where I may send my junk e-mail to so it can be analyzed or dealt with? Really, anything at all that can be done so I feel like I'm making a difference instead of just bending over and taking it?
Linux Business

Submission + - Alan Cox files patent for DRM

booooh writes: "Alan Cox has filed a patent for DRM (Digital Rights Management). em-dt20050623ptan20050138406.php
A rights management system monitors and controls use of a computer program to prevent use that is not in compliance with acceptable terms.
The nice things about this are:
  1. According to Red Hat's patent pledge they will not license this technology if the patent is granted, but rather will probably sue to avoid others using it.
  2. It can probably be applied to the DRM that is in Vista...
see more details at: .php?p=2574359"

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