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# ft\_putchar

Objective:

The first exercise in the C00 project is about implementing a simple function called `ft_putchar`. This function will take a single character as input and print it to the screen.

***

### What You Will Learn:

* **Basic C Syntax**: Writing your first function in C, defining function prototypes, and understanding function calls.
* **I/O (Input/Output) Operations**: How to output data to the console.
* **Norminette**: Learning how to follow coding standards and write clean, readable code.
* **Compiling and Testing**: How to compile your C code and test it to make sure it works.

***

### The Task:

You need to write a function `ft_putchar` that prints a character to the screen. It should look like this:

```c
void ft_putchar(char c);
```

#### Example:

If you call `ft_putchar('A');`, it should output:

```css
A
```

#### Step-by-Step Breakdown:

**1. Write the function `ft_putchar`:**

The function `ft_putchar` will take a character `c` as an argument and will output that character to the console using the standard library function `write`.\
The `write` function is defined in `unistd.h` and is used to output data to files or streams. The console is represented by file descriptor `1`.

**2. Function Implementation:**

```c
#include <unistd.h>

void ft_putchar(char c)
{
    write(1, &c, 1);  // Writes the character c to the standard output
}
```

* `write(1, &c, 1)`:
  * `1` refers to the file descriptor for the standard output (the terminal).
  * `&c` is the address of the character `c`. We need to pass a pointer to `write()`, so we use the address operator `&`.
  * `1` is the number of bytes to write. Since we are printing a single character, we specify `1`.

**3. Compiling the Code:**

To compile your C code, you'll use the `gcc` compiler. From the terminal, navigate to your project directory and compile your code using:

```sh
gcc -Wall -Wextra -Werror -o ft_putchar ft_putchar.c
```

* `-Wall -Wextra -Werror` are compiler flags to enable warnings and treat them as errors, helping you write better code.

After compiling, you can run the program like this:

```bash
./ft_putchar
```

However, since this function doesn’t have any direct output (it’s just a single character), you’ll need to test it in a program like:

```c
"ft_putchar.c"

int main() {
    ft_putchar('A');  // This should print 'A'
    return 0;
}
```

**4. Testing:**

After compiling, run the program. If everything is correct, you should see the character `A` printed on the terminal.

<mark style="color:red;">**Before submitting your project, comment out or remove your main function.**</mark><br>


---

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