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Massacring C Pointers

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Re: Massacring C Pointers

#161

Post by GrumpyYoungMan »

klodolph wrote: post #143
eesmith wrote: post #74

Earlier quoted context omitted.

To be fair, he said that about a lot of mainstream languages back then. That quote is from EWD498 at http://www.cs.utexas.edu/users/EWD/transcriptions/EWD04xx/EW... . The larger context is (the rest of the comment quotes him): FORTRAN —"the infantile disorder"—, by now nearly 20 years old, is hopelessly inadequate for whatever computer application you have in mind today: it is now too clumsy, too risky, and too expen…

Having a discussion with someone who quotes Dijkstra can be frustrating. He wrote Go To Statement Considered Harmful and On the Cruelty of Really Teaching Computer Science and left behind a bunch of pithy quotes to mine besides. You end up having to explain why blanket bans on goto don't make sense, why it really is quite difficult to mathematically prove that a program works, or why it makes sense to teach students…

> Having a discussion with someone who quotes Dijkstra can be frustrating.

Agreed. Most of the time, it seems the pithy quotes are the only thing that the quoter knows about Dijkstra.

> You end up having to explain why blanket bans on goto don't make sense

For Dijkstra's GOTO quote specifically, there's a wonderful document by David Tribble named "Go To Statement Considered Harmful: A Retrospective" that does a line-by-line analysis of Dijkstra's paper and explains what Dijkstra's meant in the context of his time and examines where usage of GOTO still makes sense today.

http://david.tribble.com/text/goto.html

Re: Massacring C Pointers

#162

Post by Cerium »

goldenkey wrote: post #120
feintruled wrote: post #111

Earlier quoted context omitted.

What's also sad is some idiot went there from that link and left an abusive comment on his memorial website referencing Hacker News. Pretty pathetic, whoever did that.

I think I speak for all the developed brains on this website when I say that defacement is pathetic and weak, clearly coming from an impotent individual. Rest in peace Mr. Traister, we love you even though C kinda thorned ya. :-)

Or as my mother taught me: "people who write in public places have stupid names and ugly faces."

Re: Massacring C Pointers

#163

Post by Wrongthink »

beojan wrote: post #153
setquk wrote: post #70

This doesn't surprise me really. When I was at university the programming textbooks we had were vile nasty and plainly incorrect. And those of us who dared challenge it by writing correct, robust code were penalised as the staff teaching it didn't understand the domain of what they were teaching properly and didn't have any real experience and assumed we were doing it wrong. We learned quickly to approach education w…

And that's why just going to the cheapest university is a bad idea.

My mid tier university has a fundamental problem where the lecturers aren't even hired to teach, they're hired for research. And since the university can't get enough American grad students to stay and be research slaves they bring in grad students from the third world. Then these grad students are required by law to teach a certain number of credit hours to conduct research and there you go. The result is every general class is poorly taught by people who can barely speak English and don't care about teaching so you end up teaching yourself or failing.

CS courses generally don't have this issue but they do have a large amount of mediocre professors. Reason being anyone talented in CS can make 2-3x the salary out in the real world and so CS grads rarely stick around to teach.

The saying "those who can't do, teach." is as relevant as ever.

Re: Massacring C Pointers

#164

Post by mikeash »

icedchai wrote: post #157
mikeash wrote: post #155

Earlier quoted context omitted.

I think the JS comparison undersells it. Many computers would literally drop you into a BASIC prompt at boot. I remember my first encounter with MS-DOS and finding it weird that you had to actually run a program to get to BASIC.

Yes, you are absolutely correct! BASIC seemed much more accessible on early microcomputers, when compared to any programming language today. Basic essentially was the OS. The Apple II, C64, etc. extended basic with DOS-like commands. They often shipped with BASIC manuals!

Apple’s guide to AppleSoft BASIC came with my IIGS and was my first programming book. It seems so much harder to get started now.

Re: Massacring C Pointers

#165

Post by [deleted] »

mikeash wrote: post #112
nwmcsween wrote: post #39

Earlier quoted context omitted.

The issue with really learning computer science outside top well known schools is that you're basically on your own for education (or worse if taught wrong). Open source software somewhat teaches you things but usually by trial by fire.

I went to an unknown state school and I got a damned fine education. Top schools don’t have a monopoly on good teachers or good students, not even remotely close.

[deleted]

Re: Massacring C Pointers

#166

Post by setquk »

Wrongthink wrote: post #163
beojan wrote: post #153

Earlier quoted context omitted.

And that's why just going to the cheapest university is a bad idea.

My mid tier university has a fundamental problem where the lecturers aren't even hired to teach, they're hired for research. And since the university can't get enough American grad students to stay and be research slaves they bring in grad students from the third world. Then these grad students are required by law to teach a certain number of credit hours to conduct research and there you go. The result is every gene…

This was exactly my experience 20 years ago. Shame things haven’t changed.

Re: Massacring C Pointers

#167

Post by saagarjha »

gmueckl wrote: post #88
saagarjha wrote: post #45

Earlier quoted context omitted.

I was referring to std::string, which is what you should be using if you're handling textual data natively.

And it's even possible to use std::string as a buffer for binary data including NULs. I won't recommend it, but it works.

I'd suggest using a std::vector of byte-sized integers for clarity, though there's nothing wrong from a standards point in using a std::string.

Re: Massacring C Pointers

#168

Post by mannykannot »

blub wrote: post #113
irishsultan wrote: post #109

Earlier quoted context omitted.

This doesn't explain why one would ever want to return a pointer to a local variable.

As mentioned by another commenter, they were probably targeting the Keil C51 compiler which stores local function arguments in fixed memory locations: https://news.ycombinator.com/item?id=17399633

By following the link in that post, you can see that this is a niche product, for the Intel MCS-51 microcontroller.

Re: Massacring C Pointers

#169

Post by mannykannot »

bitL wrote: post #135
mikeash wrote: post #126

Earlier quoted context omitted.

Unless the book states this explicitly and explains that their examples are only good with that compiler and are not actually valid C, that doesn’t really help.

Why would you assume the book author (if he indeed used Keil C51) would be aware of more dialects and their intricacies? Do you really think that in the early 90s there was a wide-spread rigor in software books? There was no Internet, whatever software one could get was the one that was their "standard", there was very limited knowledge exchange between academia and practitioners etc.

In the 90's there was at least one good software book: 'The C Programming Language' by messrs. Kernighan and Ritchie - you may have heard of it? It correctly told you, among other things, everything you really need to know about using pointers in C. It is still available.

Re: Massacring C Pointers

#170

Post by __david__ »

Oh wow, I have the "Going From BASIC to C" book! I remember reading it first because I knew Apple BASIC really well. I also had K&R. Looking back, I wonder if learning C was made harder or easier by that book…
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