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