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


Forgot your password?
Compare cell phone plans using Wirefly's innovative plan comparison tool ×

Comment Re:I don't get it (Score 1) 130

The funny thing being, of course, that I actually do thermal testing on spacecraft and therefore have a good idea of what's involved in their construction, whereas you are presumably a pale basement dweller who has zero real-world experience of any kind but believes he knows everything because he has read about it on the internet once.


Comment Re:I don't get it (Score 4, Interesting) 130

Dude, my job is doing thermal testing on spacecraft. I can tell you thermal design involves just slightly more than "wrapping a mylar blanket around it".

Also, the fact that rocket stages and habitats are both in some sense metal boxes does not in any way imply they are therefore interchangeable. Both are highly specialized parts that have very different goals. Rocket stages simply cannot afford all the extra weight necessary for them to function as a habitat (life support equipment, solar cells, meteorite shielding, access hatches, equipment for the astronauts to do useful work with, etc.). Besides, the biggest (lower) stages never make it into orbit anyway (only the top stage does, and why do you think that is?). The top stage is typically quite small. It's also not just a hollow shell; inside are multiple tanks (for fuel and oxidiser), the engine itself, pumps, electronics, etc. You'd have to remove all that.

So let's say you want to add all the necessary equipment later. How is it going to get into orbit? For that you need _another_ launch! And then you need to do a hell of a lot of precision engineering in one of the most hostile environments known to mankind, just to remove the old contents of the stage, and replace it by new contents which you might as well have launched ready to use from Earth (the weight is going to be the same, whether you pack it up tightly or not, after all).

You also have to come up with a plan to get rid of any remaining fuel. If it's hydrazine (not uncommon on upper stages), that's pretty toxic, and no, you cannot just open the hatch and hope it disappears into space.

Comment Re:I don't get it (Score 3, Interesting) 130

So an empty metal container made for storing fuel is also a great place to live? It has precisely the right properties in terms of structural integrity, heat and radiation shielding, etc.? Putting all the required machinery to sustain life inside is cost-free?

Or, if it is none of those things, changing all that stuff in orbit is actually cheaper and easier than launching a complete habitat from earth?

(hint: the answer to all these questions is "no")

Comment Re:You Can't Learn To Program In A Classroom (Score 1) 85

There's just such a mountain of crap on stackoverflow. Newbies are apparently all of them trying to reimplement std::vector or std::list, and they all want to do C-style strings. Worse, they get all offended when you point them towards the standard library solutions. Apparently there's some truly lousy teachers around... The weird thing about C++ is that it is actually bloody easy if you stay away from the crappy C parts, but since everyone seems hell-bent on doing things in as complicated a fashion as possible it makes it look like a difficult language.

Anyway, you should possibly have given that evidence to the manager in a private setting, so he could avoid losing face (and perhaps avoid some of the damage as well). Someone must have given that coworker access to production, after all...

Comment Re:Always one (Score 3, Insightful) 57

Indeed, one password is not nearly enough. Each file should have its own password! Consisting of at least 38 characters that are randomly generated and consist of lowercase, uppercase, punctuation, digits, Chinese, whitespace, and dingbats! And changing every 24 hours!

In fact I don't think that's secure enough yet. Maybe we should just not allow any 'files'. That way the hackers can never take them.

Do security people even understand that one of the primary goals of security must always still be that it must still be possible for work to be done? That, despite everything, they are a _service_, not a goal? That without any work going on, they will also be out of a job?

Comment Re:When everything you do (Score 4, Insightful) 538

So why are so many distros using it? Maybe you should just take that as a hint to take it more seriously?

What is the actual problem of using systemd as a mount tool? I've read the entire thread and not seen a single complaint other than the fact that it is "systemd by leonart poetering", which to me seems like an extremely childish case of shooting the messenger.

Comment Re:Kick Oracle right in their cash-cow (Score 1) 182

For the love of God, please don't. That way we would end up with ads in our query results, and three years down the line it gets discontinued without warning.

Besides, they could simply translate 'oracle' into 'postgresql' in all web searches without messing PostgreSQL up. May be hard on the people trying to learn about the PostgreSQL of Delphi, but for the rest I don't see much of a problem.

Comment Re:Shying away from OOP(s) (Score 1) 674

That "tiny fraction" includes pretty much everything with a 3D renderer, i.e. virtually all games, lots of visualisation tools, etc. And do enlighten us on all those abuses; maybe the people I work with are just too smart, but the only uses I've seen in their work or in the open source tools I've examined were by and large responsible.

Another huge class of useful overloads are those for operator[] (for arrays and array-like things like maps), operator() (for functors, although that role is now taken over by lambdas), and operator-> for smart pointers. All of which I would positively hate to do without. I'll admit to not being fantastically happy about using operator to stream stuff (not that it's a disaster), but being able to manipulate strings with operator+ or operator== is great.

Comment Re: Goto (Score 1) 674

Throwing exceptions for failed resource deallocation is a very bad idea, and is strongly frowned upon in the C++ community (since it might lead to the double exception problem). I have _never_ seen any piece of software that had an appropriate response for close() failing anyway, whether it was based on exceptions or return codes. If Java throw an exception in that case it's braindead language design, and not so much a sign of a general problem with exceptions.

Like all the tools in the toolkit, and like every language, _how_ you use it matters.

Comment Re:Goto (Score 1) 674

Exceptions are great: they let you separate error generation from error handling in a very clean and straightforward way. They make it impossible to 'just ignore' error conditions as well. They remove mountains of error handling code from places where it doesn't belong, making the intent of the surrounding code much clearer. Being non-local is not a problem, it is a vital feature.

As for 'not knowing which code can throw' - learn the mindset that all code can throw, and work from there. It means learning how to properly use RAII, which also helps making your code much cleaner.

Slashdot Top Deals

There must be more to life than having everything. -- Maurice Sendak