Tenacious C: Cool C IDE

by Maakuth • 16 years ago

160 41 16 years ago

mx12• 16 years ago

Just from the screenshots it looks like it might be a good tool for teaching students learning about pointers.

stcredzero2• 16 years ago

This is probably one of the best things that's happened for programming education in years! (In addition to a lot of other uses.)

mitjak• 16 years ago

Indeed. Its UI is almost exactly what my professor drew out on the blackboard during the pointers introduction. Still took a while to sink in though.

Groxx2• 16 years ago

I've been waiting for something to implement at least something DDD has done for years... and less fugly is nice. Any idea how it handles circular references?

http://www.gnu.org/software/ddd/all.png

Maakuth• 16 years ago

Whoah, how have I missed ddd completely! I'll definitely give it a try soon. Anyway, I don't know any details about Tenacious C, they are just launching in December.

xtacy2• 16 years ago

What would be interesting is if someone made a web-based GUI wrapper around such apps. I am sure it would be possible, considering that curses-based wrappers have been around: http://zemljanka.sourceforge.net/cursed/.

anonymous236• 16 years ago

And put it in the Cloud of course. That would totally rock, ninja-style.

;)

stcredzero2• 16 years ago

There's a commercial extension of Seaside, where they've put all of the Smalltalk development tools and made AJAX webapps out of them. Basically, you can set things up then do everything through the browser. (Webvelocity)

ramchip• 16 years ago

> a web-based GUI wrapper

...why would you want to do that for a C debugger?

groaner• 16 years ago

Now I know what Walter Bright should have named his software development toolchain...

SkyMarshal• 16 years ago

Good top post on the blog page, made me lol:

'I like C, but I have to admit that, sometimes, “The Old Man of Programming” can be a bit of a killjoy. This is one of the most exciting eras in computer history, but lately, C’s acting like he doesn’t even want to have a good time. While the cool kids like Ruby and Haskell are living it up, C’s over in the corner obsessing over bits and bytes and memory alignment and pointers and the stack and machine architecture and unreachable allocations and multiple indirections…and it’s…kind of a buzzkill. You want to tell him, “Dude! Lighten up! This is supposed to be fun!”

But of course C can’t relax. He’s holding the entire computing universe on his shoulders, after all. It’s not turtles all the way down — it’s turtles all the way down, __then C__. Not a lot of room for fun underneath that, is there?

Is there?

Well. Here’s the secret: C does let loose sometimes. And after being bottled up for so long, when the release finally does come, it’s pretty much an F5 of crazy.'

philbo6• 16 years ago

The blog post is excellent. It led me to this:

http://www.lysator.liu.se/c/duffs-device.html

I've programmed in C a fair amount, but I am incapable of understanding the construct contained therein. Specifically, the interaction of the switch and the loop and all those fall-through cases. I would absolutely love it if some C-guru hn-er could describe it in layman's terms?

Sindisil• 16 years ago

It's really less complex than it appears, especially once you grok that switch/case is just a computed goto; cases are just labels.

So, the idea behind Duff's Device is just to unroll a loop, dealing in an elegant (some would say abhorrent - they're wrong) way with the "leftover" portion.

So, the canonical Duff's is copying shorts, with the copy loop unrolled to eight copy statements inside the loop. If you want to copy, say 47 shorts, the loop would need to iterate five times, and there would be seven shorts left to copy.

Duff's uses the switch to jump into the middle of the loop just far enough to copy those seven leftover shorts (47 % 8 = 7). The do-while then proceeds to run through the five full iterations.

Modern compilers will do that for you now, though there are still applications for similar code.

Hope that helps.

Figs2• 16 years ago

I made you a crappy flowchart that demonstrates Duff's Device (with 4 cases rather than 8 since I'm lazy):

http://i.imgur.com/L73ai.png

The basic idea is that the switch jumps into the body of the loop somewhere, after that it can do blocks of the same function over and over without having to do the conditional check to exit the loop as often.

For example, if you're copying memory, and you want to copy say, 9 bytes then you'd jump into the loop, copy 1 byte, run the conditional check, realize that you're not done, and then copy 8 more bytes, run the conditional check, realize you're done and exit the loop. For the 8*n times you run through the "unrolled" loop after that first pass through, there are a lot less conditional branches, so many processors can execute those instructions faster. That's the idea, anyway.

silentbicycle3• 16 years ago

The other two comments are right, but the context you might be missing is why you would unroll a loop. Due to cache behavior (and other low-level details), doing something eight times and then checking if it needs to be done another eight times has less overhead than checking after each loop iteration. Why eight? It was probably a sweet spot in time vs. code size, at some point. (Processor caches are larger now.)

Duff's device just gets the (remainder of N/8) steps out of the way the first time through, then drops down to looping eight at a time. If it seems more complicated than that, you're probably overthinking it. It's "just" a creative abuse of C syntax, a bunch of offsets and gotos.

Sometimes low-level optimization like this makes a huge difference, but make sure it's a hotspot first, and that the compiler isn't already doing those things for you. Measurements will keep you objective.

Also, if you're doing a lot with C, check out Lua!

edanm• 16 years ago

A good explanation was posted here a few days ago: http://news.ycombinator.com/item?id=1896643

(After looking it up, I discovered it was from the same site.)

bsk• 16 years ago

Is this a port of http://en.wikipedia.org/wiki/Tenacious_D ? ;-)

ecounysis• 16 years ago

yes

rogerclark2• 16 years ago

What a joke. Things like this – and the rhetoric on his site – make systems programming look like more of a dark art than it actually is.

If you're a programmer, should know how your computer works; if pointers are too "hard" for you, you're in the wrong business. You're settling for mediocrity and belittling your own intelligence by assuming you're not capable of tackling this stuff the same way everyone else has.

angrycoder• 16 years ago

I dunno, I have a lot respect for people who take difficult concepts and try to make them easier to grasp.

Teachers are more valuable than belittlers. "This isn't hard" is not a lesson plan or a path to enlightenment.

rogerclark2• 16 years ago

I also have a lot of respect for people who are willing to teach. But I don't respect teachers that speak of these concepts like they're magic that no mere mortal can understand. This is stuff that everyone can know -- and should know -- and needs to be treated like learning arithmetic, not tensor calculus.

noarchy• 16 years ago

How many programmers today do not know what what a pointer is, or even if they do, how to use/understand them? I'm sure the number is growing, considering the prevalence of languages where pointers aren't even a consideration.

Now if you don't like the features of this IDE, that's fair. You're free to stick to whatever you're currently using. Given that Tenacious C will be a paid app when it is done, I doubt I'll really be interested, given what I can use for free that gets the job done more than adequately.

philbo6• 16 years ago

Gah, I can't remember the details now, but I'm sure one of the interviewees in Coders At Work talks about this point. Something about how the notion of pointers/references is fundamentally wrong because it doesn't reflect our understanding of objects in RL.

I realise I'm being tangential now, but thought I'd mention it anyway.

jrockway• 16 years ago

My thoughts exactly. Pointers are one of the easier "computer science concepts". Instead of storing the entire value right here, we just store where in memory that is. That's all. The side-effects are also relatively simple. Since we're just passing around memory addresses, anything (including called functions) can modify it, since they just write to that memory.

If you can't understand that, I don't see how you are going to write a computer program. The deeper issues are things like object lifetimes, call-by-value versus call-by-reference semantics, and so on.

dinkumthinkum• 16 years ago

Neat, but I question the Windows only choice here. A lot of C programmers are developing on a *nix platform. But I see this as being more useful for students learning C and memory management. It's a neat project and might recommend it to students but I'll stick to vim, myself.

TimMontague• 16 years ago

They seem to be targeting the embedded market, which is mostly Windows based.

sliverstorm• 16 years ago

Of course, if you learned assembly first instead of Java or somesuch, pointers make 100% intuitive sense, and if you didn't grok them completely you wouldn't have been able to write your first program.

Tenacious C: Cool C IDE

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