Many services provided by an operating system require higher privilege levels than the user in order to efficiently and/or effectively provide that service. This is why setuid exists, and this is also where security holes pop up frequently.
With some newer languages, like C# and Java, this 'service' concept has been extended up into the libraries. This includes things like resource caching (URLs, decoded images, etc), or opening files on the filesystem on your behalf.
There's only one problem. Now that the service you're accessing isn't running in a different memory space, it can't protect itself from your grubby hands using typical OS facilities like memory protection. The only recourse they have is to provide their own brand of memory protection.
In other words, they do, in fact, say that (at least in the case of sandboxed code) member privacy provides security, because they HAVE to.
I've had to strong-arm a number of my friends into seeing it, over the years. I think the name is a bit off-putting, and so they grumble about being forced to watch some dumb movie. But every last one of them has admitted afterward that it was a pretty good movie.
There was a small group, The First Millenial Foundation that formed up in the mid nineties to try to apply some of the ideas from his book, but the wind in their sails slowly petered out. Lots of people with really good ideas, but geographically isolated, and so no momentum got going.
A couple of years ago, Marshall stepped down from the organization, and it changed its name to the Living Universe Foundation, which was about the time I stopped following their progress.
One of the biggest roadblocks was that the man who came up with 'seacrete' (Hilbertz?), the limestone electrolysis process that was intended to grow the floating cities and use up their excess electricity, is very secretive, and his published processes didn't seem to contain enough critical detail, and proved difficult to replicate by the hobbyists. Also, there was some difficulty figuring out the bootstrapping problem of setting up an OTEC unit in deep ocean water, and then growing a giant spire above it.
I've actually gotten to the point where I refuse to deliver mockups. The very earliest thing you will see from me is a functioning prototype, and even that makes me nervous. I generally aim for delivering the application in vertical slices, so that there is no, "Oh, it all looks okay to me, let's ship it", because there is no 'all' yet.
Maybe you missed the memo, but Iraq hasn't been able to sell oil anywhere near capacity for more than ten years. Have you heard the phrase 'Food for Oil'? That's about Iraq.
Iraq has at least 100 billion barrels of oil by conservative estimates, and 300 billion by some people's estimates.
Start with Oil Crisis and educate yourself from there.
Perhaps I should point out a couple more items, before someone calls me on it. I've simplified things a bit in the above description. Firstly, the C-to-C concept is perfectly 'happy' with any circular feedstock dependency. If you can turn soda bottles into coats, and then those coats into soda bottles, you've still closed the loop.
Secondly, it's also entirely likely that 95% recyclability might not be achievable, or if it is, that it is so because 95% of each bottle is old material, and the 5% is material that's irreparably deteriorated in the recycling process. The ingredients that make a particular item stiff, or flexible, may not entirely survive the process, and need to be replaced.
And last but not least, for any of this to work, your process can't produce a toxic sludge that gets flushed down the drain, or you've made a bigger mess than you already had.
He did not stutter, the concept is in fact called Cradle to Cradle. It's a concept presented in a book by the MDBC founders called, Cradle to Cradle [slashdot], in which they claim, rather reasonably, that you're not -really- recycling unless the product you produce is of equal or greater material quality than the product you started with.
If you take petroleum, and make soda bottles, and then you take soda bottles and make them into seat cushions and polyfill for coats, blankets, etc, you've recycled the material only once, but you can't recycle polyfill into anything useful, so it goes into the landfill when you're done with it.
You've recycled the material once, doubling its lifetime. In a perfect world, you're reducing the waste stream by only half, by making every coat from recycled material, and new bottle with new material. Cradle to Cradle says, let's make that soda bottle out of a plastic that can be broken down and made back into feedstock for making soda bottles, and coats out of material that can be made out of coats. In other words, returning it to the Cradle. Assuming some wear and tear on the materials, you still could expect to recycle more than 95% of the bottle back into another bottle. Now, in a perfect world, 19 of every 20 bottles is made from recycled material, ditto for coats.
Cradle to Grave just means someone is responsible for the eulogy, which will eventually be ours if we don't stop dumping high-grade materials into holes in the ground.
Because the Space Shuttle is by far the most complicated piece of equipment ever built?
A lot of the thrust in new designs is to reduce the complexity of the system, and thereby reduce maintenance costs. Simplifying and lightening the Space Shuttle design by 20% just isn't going to cut it.
So, tell me, since it was so easy to fix what was wrong with your life, why didn't you do it five years ago? What would that version of yourself tell you if you ran into him today? He'd probably tell you to go get stuffed.
Having been on both sides of a problem doesn't give you empathy, if you never had any to begin with. It just gives you a feeling of entitlement.
Quitting an addiction when you have an addictive personality can be a tricky thing. There's a tendency to fill the hole with another addiction, like the proverbial Alcoholics Anonymous meeting full of chain-smokers. I'm curious how you managed to compensate.
Isn't that sort of like the idea that, say, Dell, or Gateway, should be able to do anything they want with THEIR PRODUCT, including the decision to not include other people's products?
I've played with one of these a bit, and I must say that the physical design needed a lot of work. The mounting for the stylus is nothing short of awful. Shaped roughly like a wooden coffee stirrer, it fits flush into the side of the device. To remove it, you push up on it with your thumb. Then, with it pinched precariously against the side of the device, you have to shift your grip to grab it. Since it's flat, this may be difficult for the less dexterous. To make things interesting, it's translucent blue, and nearly transparent. Should you drop it on the floor, you'll need a good bit of luck finding it again.
Heat engines convert temperature -differences- into mechanical energy. If you plop one inside a furnace, it'll just sit there getting warm. Reversible in this case means that you can convert mechanical energy into a temperature difference, and so it can be used as either a heat pump or as a refrigeration unit, depending on which end of the output you're interested in.
Bounds-checking eliminations have been around for years. While work is still being done to expand the available techniques, boundary elimination as it stands today eliminates checks on most reasonable uses of arrays.
If you want to bash Java, there are plenty of ways to do it with an informed opinion, but that holds true with any language.
But an electronic book means that you can search the entire text for a phrase. And not only would a proper one allow you to write in the margins, but it would be able to index your annotations.
Do you really need to dog-ear the pages if you can simply do a search on the book for everywhere you wrote 'cool quote'?
In an interview, you get time to ask maybe a dozen questions of the interviewee.
Every question counts.
It doesn't matter how sure you are that a question is good, if it's controversial at all, you should throw it out without a second thought, because you're basing a significant fraction of your value judgment about a person on a question of arguable merit.
Pick something else to ask about.
At my company, we like to use programming questions that cover material every developer has to know, but won't use every day, and so generally will have to exert a little bit of quick thinking to accomplish. Like writing a hash function (any hash will do), collection classes, clone methods, or nontrivial synchronization.
My primary focus in VM/language design is in agressive continuous optimization techniques, however, if/when I achieve my preliminary goals in that arena, one of the possibilities I see going forward is to create an OS that can run trusted user code closer to ring0 than untrusted native user code. This reduction in system call costs would partially offset the increased processing needed for the interpreter.
In order to get access to a large library of native code, there are a number of linux projects that allow the kernel to be hosted on top of another OS, from Windows (Plex86), to various microkernels (like L4Linux), to Linux itself (User Mode Linux). Port Linux to your VM in a fashion similar to these guys, and you get your compatibility.
> It has been oft-observed that you cannot successfully apply a technological solution to a social problem.
And yet, your car has anti-lock brakes, three-point harnesses, and airbags... Is that not a technological solution to the social problem of bad drivers?
I suspect a radio transponder wouldn't work too well when it's tucked away inside a metal business card or cigarette case. $15 bucks is a small price to pay for a little privacy.
If I were a discerning alien, and I knew how to make and detect coherent gravity waves, interstellar electromagnetic communication would be awfully silly. It's certainly more likely that some sort of faster-than-light communication really exists than that we are the only intelligent life in the universe.
Slashdot Mirror
Many services provided by an operating system require higher privilege levels than the user in order to efficiently and/or effectively provide that service. This is why setuid exists, and this is also where security holes pop up frequently.
With some newer languages, like C# and Java, this 'service' concept has been extended up into the libraries. This includes things like resource caching (URLs, decoded images, etc), or opening files on the filesystem on your behalf.
There's only one problem. Now that the service you're accessing isn't running in a different memory space, it can't protect itself from your grubby hands using typical OS facilities like memory protection. The only recourse they have is to provide their own brand of memory protection.
In other words, they do, in fact, say that (at least in the case of sandboxed code) member privacy provides security, because they HAVE to.
I've had to strong-arm a number of my friends into seeing it, over the years. I think the name is a bit off-putting, and so they grumble about being forced to watch some dumb movie. But every last one of them has admitted afterward that it was a pretty good movie.
You know. For kids.
There was a small group, The First Millenial Foundation that formed up in the mid nineties to try to apply some of the ideas from his book, but the wind in their sails slowly petered out. Lots of people with really good ideas, but geographically isolated, and so no momentum got going.
A couple of years ago, Marshall stepped down from the organization, and it changed its name to the Living Universe Foundation, which was about the time I stopped following their progress.
One of the biggest roadblocks was that the man who came up with 'seacrete' (Hilbertz?), the limestone electrolysis process that was intended to grow the floating cities and use up their excess electricity, is very secretive, and his published processes didn't seem to contain enough critical detail, and proved difficult to replicate by the hobbyists. Also, there was some difficulty figuring out the bootstrapping problem of setting up an OTEC unit in deep ocean water, and then growing a giant spire above it.
Yes, exactly.
I've actually gotten to the point where I refuse to deliver mockups. The very earliest thing you will see from me is a functioning prototype, and even that makes me nervous. I generally aim for delivering the application in vertical slices, so that there is no, "Oh, it all looks okay to me, let's ship it", because there is no 'all' yet.
A quote I use frequently, when discussing software, schedules, and code bloat:
"I apologize for the length of this letter. If I had had more time, I would have written a shorter one."
-Mark Twain
Maybe you missed the memo, but Iraq hasn't been able to sell oil anywhere near capacity for more than ten years. Have you heard the phrase 'Food for Oil'? That's about Iraq.
Iraq has at least 100 billion barrels of oil by conservative estimates, and 300 billion by some people's estimates.
Start with Oil Crisis and educate yourself from there.
The main problem I see with the 3ware cards is that they are all PCI 64. What do us poor slobs without 64 bit slots do?
Perhaps I should point out a couple more items, before someone calls me on it. I've simplified things a bit in the above description. Firstly, the C-to-C concept is perfectly 'happy' with any circular feedstock dependency. If you can turn soda bottles into coats, and then those coats into soda bottles, you've still closed the loop.
Secondly, it's also entirely likely that 95% recyclability might not be achievable, or if it is, that it is so because 95% of each bottle is old material, and the 5% is material that's irreparably deteriorated in the recycling process. The ingredients that make a particular item stiff, or flexible, may not entirely survive the process, and need to be replaced.
And last but not least, for any of this to work, your process can't produce a toxic sludge that gets flushed down the drain, or you've made a bigger mess than you already had.
He did not stutter, the concept is in fact called Cradle to Cradle. It's a concept presented in a book by the MDBC founders called, Cradle to Cradle [slashdot], in which they claim, rather reasonably, that you're not -really- recycling unless the product you produce is of equal or greater material quality than the product you started with.
If you take petroleum, and make soda bottles, and then you take soda bottles and make them into seat cushions and polyfill for coats, blankets, etc, you've recycled the material only once, but you can't recycle polyfill into anything useful, so it goes into the landfill when you're done with it.
You've recycled the material once, doubling its lifetime. In a perfect world, you're reducing the waste stream by only half, by making every coat from recycled material, and new bottle with new material. Cradle to Cradle says, let's make that soda bottle out of a plastic that can be broken down and made back into feedstock for making soda bottles, and coats out of material that can be made out of coats. In other words, returning it to the Cradle. Assuming some wear and tear on the materials, you still could expect to recycle more than 95% of the bottle back into another bottle. Now, in a perfect world, 19 of every 20 bottles is made from recycled material, ditto for coats.
Cradle to Grave just means someone is responsible for the eulogy, which will eventually be ours if we don't stop dumping high-grade materials into holes in the ground.
Because the Space Shuttle is by far the most complicated piece of equipment ever built?
A lot of the thrust in new designs is to reduce the complexity of the system, and thereby reduce maintenance costs. Simplifying and lightening the Space Shuttle design by 20% just isn't going to cut it.
Perhaps it escaped your attention that the motorcycle user interface is modeled closely after the horse user interface?
At the time, the car was the disruptive interface change.
Well, obviously you have the answers then.
So, tell me, since it was so easy to fix what was wrong with your life, why didn't you do it five years ago? What would that version of yourself tell you if you ran into him today? He'd probably tell you to go get stuffed.
Having been on both sides of a problem doesn't give you empathy, if you never had any to begin with. It just gives you a feeling of entitlement.
Quitting an addiction when you have an addictive personality can be a tricky thing. There's a tendency to fill the hole with another addiction, like the proverbial Alcoholics Anonymous meeting full of chain-smokers. I'm curious how you managed to compensate.
Isn't that sort of like the idea that, say, Dell, or Gateway, should be able to do anything they want with THEIR PRODUCT, including the decision to not include other people's products?
I've played with one of these a bit, and I must say that the physical design needed a lot of work. The mounting for the stylus is nothing short of awful. Shaped roughly like a wooden coffee stirrer, it fits flush into the side of the device. To remove it, you push up on it with your thumb. Then, with it pinched precariously against the side of the device, you have to shift your grip to grab it. Since it's flat, this may be difficult for the less dexterous. To make things interesting, it's translucent blue, and nearly transparent. Should you drop it on the floor, you'll need a good bit of luck finding it again.
Heat engines convert temperature -differences- into mechanical energy. If you plop one inside a furnace, it'll just sit there getting warm. Reversible in this case means that you can convert mechanical energy into a temperature difference, and so it can be used as either a heat pump or as a refrigeration unit, depending on which end of the output you're interested in.
Bounds-checking eliminations have been around for years. While work is still being done to expand the available techniques, boundary elimination as it stands today eliminates checks on most reasonable uses of arrays.
If you want to bash Java, there are plenty of ways to do it with an informed opinion, but that holds true with any language.
Maybe you should point out to them that many of the Agile Process folks are fond of saying, "Good Process is no substitute for Good People."
But an electronic book means that you can search the entire text for a phrase. And not only would a proper one allow you to write in the margins, but it would be able to index your annotations.
Do you really need to dog-ear the pages if you can simply do a search on the book for everywhere you wrote 'cool quote'?
I saw these on the Narita train when I went to Japan in August of 1996, so it's been there for at least 6 years.
In an interview, you get time to ask maybe a dozen questions of the interviewee.
Every question counts.
It doesn't matter how sure you are that a question is good, if it's controversial at all, you should throw it out without a second thought, because you're basing a significant fraction of your value judgment about a person on a question of arguable merit.
Pick something else to ask about.
At my company, we like to use programming questions that cover material every developer has to know, but won't use every day, and so generally will have to exert a little bit of quick thinking to accomplish. Like writing a hash function (any hash will do), collection classes, clone methods, or nontrivial synchronization.
My primary focus in VM/language design is in agressive continuous optimization techniques, however, if/when I achieve my preliminary goals in that arena, one of the possibilities I see going forward is to create an OS that can run trusted user code closer to ring0 than untrusted native user code. This reduction in system call costs would partially offset the increased processing needed for the interpreter.
In order to get access to a large library of native code, there are a number of linux projects that allow the kernel to be hosted on top of another OS, from Windows (Plex86), to various microkernels (like L4Linux), to Linux itself (User Mode Linux). Port Linux to your VM in a fashion similar to these guys, and you get your compatibility.
> It has been oft-observed that you cannot successfully apply a technological solution to a social problem.
And yet, your car has anti-lock brakes, three-point harnesses, and airbags... Is that not a technological solution to the social problem of bad drivers?
I suspect a radio transponder wouldn't work too well when it's tucked away inside a metal business card or cigarette case. $15 bucks is a small price to pay for a little privacy.
If I were a discerning alien, and I knew how to make and detect coherent gravity waves, interstellar electromagnetic communication would be awfully silly. It's certainly more likely that some sort of faster-than-light communication really exists than that we are the only intelligent life in the universe.