Beej’s Guide to C Programming [pdf]

Post by Arch-TK » Fri, Apr 23, 2021, 7:09 PM UTC

mytailorisrich wrote: post #56

blunte wrote: post #6

IMO, pointers are less difficult to comprehend than other abstractions, like lambdas are. If you know how to walk down a street and stop at the right street number, then you have used pointers. And if you've ever observed that one tall building may "cover" a range of street numbers, such as 200-220, then you should understand how to move from one 4-byte "value" to the next in an array in memory. Anyway, many more ana…

C is an abstraction over assembly, really (benefits being that it is simpler by being more abstract and portable across CPU types). I've always thought that an introduction to CPUs (can take a simpler one as example) and how they work, how memory is (usually) organised, and to assembly would go a long way in helping understand many programming issues and C. My experience is that C or programming concepts are often ta…

Post by dang » Fri, Apr 23, 2021, 7:18 PM UTC

Post by wott » Fri, Apr 23, 2021, 8:02 PM UTC

mumblemumble wrote: post #124

gnuvince wrote: post #96

Earlier quoted context omitted.

What does "modern" C imply? AFAIK, there are not very many new language features; is it about organizing code differently than what one would learn from K&R?

According to the introduction of the book, C17. Which is mostly just bugfixes on C11. But, compared to c99, you get nice things like generic expressions, better unicode, and (standard) multithreading.

Post by chasil » Fri, Apr 23, 2021, 8:12 PM UTC

atoav wrote: post #12

blunte wrote: post #6

IMO, pointers are less difficult to comprehend than other abstractions, like lambdas are. If you know how to walk down a street and stop at the right street number, then you have used pointers. And if you've ever observed that one tall building may "cover" a range of street numbers, such as 200-220, then you should understand how to move from one 4-byte "value" to the next in an array in memory. Anyway, many more ana…

What pointers basically are is not particularly hard to grasp. What is harder to grasp it what can be done with them and how you can shoot yourself in the foot with them in non-obvious ways. I think I only understood much of it once I learned Rust, because you realize: Ah, that thing I once did in C is something that maybe ahouldn't be possible at all without extra steps . Even if I were to nwver use Rust again, this…

Post by oscargrouch » Fri, Apr 23, 2021, 8:45 PM UTC

qsort wrote: post #30

bluetomcat wrote: post #26

Earlier quoted context omitted.

In C, pointers require you to think deeply about the ownership and lifetime of any "allocated object" at runtime. How long does it live, who is responsible for the deallocation, how many pointers does your program hold to that object (dangling issues). Ultimately, it can lead to a cleaner design if these issues are taken seriously up-front.

I don't disagree with that, but most cases fall within a pretty clear pattern: - typedef struct { ... } foo - foo *foo_create() - void foo_destroy(foo *) - a bunch of functions that take foo* as their first arg which is kind of the same as a class and only more error-prone. I say this as someone who actually _likes_ C, but the manual memory management model is very often unnecessary, confusing, repetitive. There was…

    struct X { int a; }
    struct Y { *X; int b; int c;}

    void add(Y* self, int number) {
      self->a += number;
    }

    Y y;
    y.a = 10; // composition
    y.add(1) // y.a = 11 now