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C Wars, Chapter One: The Segfault menace

Hello, World! 🖖

To compete with @HahaYes C++ tutorial, I take the side of C, as defined in The C programming language, second edition by Brain Kerninghan and Dennsi Ritchie.

Edit: Chapter two is out

Now:

Let the games begin!

Chapter 1, part 1:

Hello World

The only real way to learn a language is to start programming in it.

So, we will do Hello world.

Code

Please make a new C repl, and enter this code into it.

(No Copy-Paste)

#include <stdio.h>

int main() 
{
    printf("Hello world\n");
    return 0;
}

Run

If you are in repl, press C-ret, or 'Run'

If you are on a *NIX system use this:

gcc hello.c -Wall -Werror -o main.o && chmod +x main.o && ./main.o

If you are on Windows, download 50G of IDE and C++/Python/NET compilers (VS) and make a new project and hope your computer won't crash.

Output

You should see this appear in your terminal:

$ gcc hello.c -Wall -Werror -o main.o && chmod +x main.o && ./main.o
$ ./main.o
Hello world
$

Chapter 1, part 2

Meta time

This section is very meta about C, and is not Strictly required.

Every C program has two parts:

Functions
Variables

Or, to be even more meta:

Code
Data

Let's dissect hello.c, line for line:

#include <stdio.h>

This may look like ~~elvis~~ elvish, but it is very simple.

The # char indicates a preprocesser directive.

The directive in question ~~Prime~~ include, includes other code in your program.

The prefix std means standard, and io means input/ouput

int main()

This is a function, or a snippet of code.

Every function has the form return_type name(args)

In this one, we have a return type of int, named main that takes no arguments

{

In C, a curly brace ({/}) seperates blocks of code.
In this case, all you need to know is that all code between { and } is part of main

printf("Hello world");

This is another function, like main.

It is named printf. In non-programmer speak, it means print with formatting. The formatting part is in Chapter two. It takes one -or two- arguments, the string to print, ~~and the format string~~.

All lines that don't start with a # or are a function end with ;. No exceptions. Ever.

In this case, we are asking it to print Hello world with no formmatting.

return 0;

This is a special statment, return. It returns a piece of Data, like a gift.
For main, the return value is normally used to tell if the program failed, or worked.

0: It worked
1: General error
2+: Random error

And, last but not least:

}

This tells your computer that your are done with main and want to move on.

Chapter 1, part 3

Your challenge

You need to make a program that prints out three things:

Your favorite Browser (Firefox)
The operating system you don't like the most (Windows 10)
Your favorite type of pet (Dog)

Please give them to me in the comments

Example output:

$ ./a.out
Firefox
Windows 10
Dog
$

Part One: The Segfault menace

Part Two: The data wars

Part Three: Revenge of the if

Part Four: A new loop

Part Five: The Empire points back

Part Six: Return of the function

Voters

3 more...

Commentshot new top

#include <stdio.h>

int main() 
{
    printf("Firefox");
    printf("Windows 10");
    printf("Guinea pig");
    return 0;
}

imma pro at coding watch me h4ck hAhAAhAhAHAHAHAHAHa

@Warhawk947

Also none of this is elvish. C is a high level language.

@Jakman I was talking about preproc directives, for non programmers.

@CodeLongAndPros ahh.

@Jakman and there’s no preprocdirs in Python.

@CodeLongAndPros well thats true. I love when people speak of the english programming language (Python).

@Jakman Yeah, but ever try to compile Python? I had a 100 mb bin.

@CodeLongAndPros im going to be real. I havent touched python in a while.

@Jakman Eh, it is somewhat high level. But, out of seriousness, it is not a "high level language". Rephrase a bit.
It is a higher level low level language :)

@targetfanttthat A middle level language.

@targetfanttthat Python is very high level. If it isnt neither is Scratch

#include <iostream>
int main() {
  std::cout << Chrome << std::endl;
  std::cout << Linux << std::endl;
  std::cout << Cat << std::endl;
  return 0;
}

its right, right?

@awesome10 Well, this is C.

Not C++.

Look at @HahaYes's for C++

@CodeLongAndPros it was on purpose

@awesome10 Well then:
FAIL

@CodeLongAndPros well then:

#include <stdio.h>
int main() {
  printf("I don't care");
  return 0;
}

@awesome10 The correct one is:

#include <stdio.h>

using namespace std;

import std.stdio: writeln;
int main() {
  writeln("Firefox");
  cout << "Windows 10\n"; 
  printf("%s\n", "Dog");
}

@CodeLongAndPros

using namespace std;

is bad and i actually like cats

@awesome10 Well, HahaYes does it...

But I know.

@CodeLongAndPros well, i never said i learned all my cpp from hahayes and i actually like both cpp and c and c# the same wait that isn't 2 things watever

@CodeLongAndPros Why thanks man

@awesome10 Where's C?

@HahaYes oh no you weren't supposed to be listening!

@CodeLongAndPros what?

@awesome10 Don't worry, I do that to him all the time.

@CodeLongAndPros i said i liked cpp, c, and c# the same

@awesome10 I have seen your comments traitor. JK XD

@HahaYes haha yes

@awesome10
Haha,
Segmentation fault (core dumped)

@CodeLongAndPros

Haha,
^~~~~~

Traceback (most recent call last):
    File <stdin>, line one, in <comment>
NameError: Haha, is not defined

@CodeLongAndPros

Haha,
^~~~~~

Traceback (most recent call last):
    File <stdin>, line one, in <comment>
NameError: Haha, is not defined

No not the traitor @CodeLongAndPros

#include <stdio.h>
int main(){
    char[] browser = "AOL";
    char[] opsys = "Bash";
    printf("I like the browser %s and hate %s. I do not like pets.",browser,opsys); 
    return 0;
}

firefox sucks

@DynamicSquid How is this related?

@DynamicSquid Oh wait.

I just like FF better than Chrome..

@DynamicSquid Firefox > Chrome > internet explorer

@HahaYes Elinks is at the top

@CodeLongAndPros hmm let me guess rick roll

@HahaYes Yeah. #2 comes out tomorrow.

@CodeLongAndPros bro anytime I see a link I think... rick roll

@HahaYes For your awareness, you get a peek at Chapter two:

Examples of not-ints:

c
134qwf
55.0456
192.168.0.0

@CodeLongAndPros no. I MUST BE BETTER THAN YOU

@HahaYes
Not to brag, but I'm great at Quiplash and can make a mean tutorial.

@CodeLongAndPros The tears of the dissapointed fans

@HahaYes You have a head start.

@CodeLongAndPros yessssss

@HahaYes But a head start means nothing, compared to the simplicity of C.

@CodeLongAndPros NO I don't like C

@HahaYes

Customer:
Morning

Waitress:
Morning

Customer:
What have you got?

Waitress:
Well, there's egg and bacon
Egg sausage and bacon
Egg and C
Egg, bacon and C
Egg, bacon, sausage and C
C, bacon, sausage and C
C, egg, C, C, bacon and C
C, sausage, C, C, C, bacon, C tomato and C
C, C, C, egg and C
C, C, C, C, C, C, baked beans, C, C, C and C

(Choir: C! C! C! C! Lovely C! Lovely C!)

Or Lobster Thermidor aux crevettes with a Mornay sauce
Served in a Provençale manner with shallots and aubergines
Garnished with truffle pâté, brandy and a fried egg on top and C

Wife:
Have you got anything without C?

Waitress:
Well, the C, eggs, sausage and C
That's not got much C in it

Wife:
I don't want any C!

Customer:
Why can't she have eggs, bacon, C and sausage?

Wife:
That's got C in it!

Customer:
Hasn't got much C in it as C, eggs, sausage and C has it?

(Choir: C! C! C!...)

Wife:
Could you do me eggs, bacon, C and sausage without the C, then?

Waitress:
Iiiiiiiiiiiich!!

Wife:
What do you mean 'Iiiiiiiiiich'? I don't like C!

(Choir: Lovely C! Wonderful C!)

Waitress (to choir):
Shut up!

(Choir: Lovely C! Wonderful C!)

Waitress:
Shut Up! Bloody Vikings!
You can't have egg, bacon, C and sausage without the C

Wife:
I don't like C!

Customer:
Shush dear, don't have a fuss. I'll have your C. I love it
I'm having C, C, C, C, C, C, C, baked beans
C, C, C, and C!

(Choir: C! C! C! C! Lovely C! Wonderful C!)

Waitress:
Shut Up!! Baked beans are off

Customer:
Well, could I have her C instead of the baked beans then?

Waitress:
You mean C, C, C, C, C, C, C, C, C, C, C
C and C?

Choir (intervening):
C! C! C! C!
Lovely C! Wonderful C!
C c-c-c-c-c-C C c-c-c-c-c-c C
Lovely C! Lovely C! Lovely C! Lovely C!
C C C C!

@CodeLongAndPros C++ better though