Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×

Comment Re:Use the OS video libraries (Score 1) 392

To display an image, at some point in some program, you'll see, if image is PNG, send it to libpng; if image is jpeg, send it to libjpg; .... We're just arguing about where that code belongs.

You could put it in the browser. Then you get a program that links directly with libfoo to display all the images it wants. My guess is that browsers do this now. It'd be the same thing to have Firefox link directly to x264 and libogg to display movies.

The alternative is to use another layer of indirection. Have a new library/system service that a browser can throw a buffer at and say "go render this." The service then discovers its type and calls libpng, libavg, .... This would be something like linking with VLC.

Education

HTML Tags For Academic Printing? 338

meketrefi writes "It's been quite a while since I got interested in the idea of using html (instead of .doc. or .odf) as a standard for saving documents — including the more official ones like academic papers. The problem is using HTML to create pages with a stable size that would deal with bibliographical references, page breaks, different printers, etc. Does anyone think it is possible to develop a decent tag like 'div,' but called 'page,' specially for this? Something that would make no use of CSS? Maybe something with attributes as follows: {page size="A4" borders="2.5cm,2.5cm,2cm,2cm" page_numbering="bottomleft,startfrom0"} — You get the idea... { /page} I guess you would not be able to tell when the page would be full, so the browser would have to be in charge of breaking the content into multiple pages when needed. Bibliographical references would probably need a special tag as well, positioned inside the tag ..." Is this such a crazy idea? What would you advise?

Comment Re:Death knell (Score 3, Insightful) 361

What good is a fault tolerant file system if it isn't tolerant of faults?

Any time you read about a product that guarantees perfect fault tolerance, there is always a list of constraints that must be met for that claim to hold. You probably won't ever see this list marketed, but it's there somewhere.

I haven't looked into this, but it sounds like ZFS is fault-tolerant given a system model where data can change once it's on-disk, but otherwise system components are fail-stop. So if you ask a hard disk to perform a write barrier and flush its data to disk, the disk will either do so and report success, it will issue an I/O error, or it will catch on fire. Any way, ZFS will handle the situation correctly.

Of course, the immediate next question is whether that failure model is realistic. Turns out it isn't. Some hardware will report 'write barrier complete' when it still has unwritten data in its buffer.

If you can't count on your hard disk to flush its caches or even order writes correctly, I don't think it's possible to build any fault-free file system on top of the drive.

What Free IDE Do You Use? 1055

postermmxvicom writes "I program only occasionally and mostly for personal interest. I went to update my favorite free IDE, Dev C++, yesterday and noticed that it had not been updated since 2005! I went looking for other free IDEs and came across Code::Blocks and Visual Studio Express. I work from a Windows machine, use C++, and make mostly console apps; but have written a few Windows apps and D3D or OpenGL apps. I wanted to know what free IDEs you use and recommend. What do you like about them? What features do they lack? What about them irritate you (and what do you do to work around these annoyances)? For instance, when I used Visual C++ 6.0 in college, there was an error in getline that had to be fixed, and the code indenting in DevC++ needed to be tweaked to suit my liking."

Comment Re:why get one of these when (Score 1) 246

As far as I understand it, wake-on-lan would let me SSH into one computer so I can send a magic packet to my real to computer to wake it up, and then I can SSH in to the computer I wanted to in the first place.

Somniloquy gives the same functionality transparently, without needing that extra step, without any other network user being aware that the computer was asleep in the first place.

If you read the referenced paper, they do talk about why they don't like wake-on-lan in section 6.

Comment Re:why get one of these when (Score 2, Informative) 246

there are so many other low-powered devices that will do so much more.

The important part of this work isn't that there is another device to do your downloading. Yes, there are better devices for that.

What these guys have done is design one way to keep your PC in low power mode as long as possible. One reason that people keep their computers on is that they want network services to be available. (Some keep their computer on because it's downloading torrents. I keep my computer on because I might want to SSH in or access my files remotely.)

This device is one way to keep a computer network-accessible while it's in a low-power sleep. (Hence the name "Somniloquy": talking in one's sleep.) They do this by putting a proxy between the computer and the network. The computer can go to sleep and have the proxy take over network functions for it.

This turns out to be a very general approach. For some types of network access, this device can get away with ignoring the data. For other accesses (like when I try to SSH in), it can wake the computer from sleep to process the request. For some trivial protocols like ping, it's easy to let the proxy just respond.

They show that it's still possible to get some power saving in complex protocols. As an illustration of its generality, they were able to implement BitTorrent within this design. Other protocols may give similar benefits. But they aren't about to implement everything out there.

Comment Re:Relations all the way down (Score 1) 187

We're still struggling with the object-relational impedance mismatch today. The closest we are to finding a "solid basis" for computer science is a general field of philosophy called "structural realism" which attempts to find the proper roles of relations vs relata in creating our models of the world.

If your biggest problem is how to represent objects in a relational database, I'd say the foundation is solid enough.

More broadly, your problem is that we don't know exactly what we should be modeling with our computers, not questioning whether computers are capable of modeling it. That's progress.

PC Games (Games)

Multi Theft Auto - San Andreas Goes Open Source 127

dan writes " Multi Theft Auto is a third-party modification for Rockstar's hit title Grand Theft Auto San Andreas — and it has become open-source after over four years of closed source development. As a (somewhat) regular player of MTA since the early days of GTAIII, this hit me by surprise, somewhat." (The news is on the project's front page, from which dan extracts more details, below.)

Comment Re:Preprocessing in C (Score 1) 60

Compiling each CPP in turn requires 10 - 100 files read off the disk each time.

Modern operating systems get around this issue with a disk cache. In reality, 100 files will be read off the disk for the first compile, and the rest of the compiles will just access the cached copy in memory (unless memory is in short supply on your system).

Media (Apple)

Submission + - iPhone gets a better battery life and more

morpheus83 writes: Talk about last minute upgrades: In a press release today, Apple has revealed a number of significant upgrades to both the iPhone's battery life and touch screen. Instead of around 5 hours of video/talk and 16 hours of audio playback, Apple has updated the iPhone's battery life rating to the following numbers: up to 8 hours talk time, a whopping 250 hours of standby (over 10 days), 6 hours of internet use, 7 hours of video playback and 24 hours of audio playback. The original 3.5" plastic surface of the iPhone has been changed to "optical-quality" glass, which should bring some smiles to those who were concerned about the durability of the phone's primary feature and user interface.

Slashdot Top Deals

Our business in life is not to succeed but to continue to fail in high spirits. -- Robert Louis Stevenson

Working...