This project has been created as part of the 42 curriculum by sarfreit.

Description

ft_printf is a 42 project that recreates part of the behavior of the standard printf() function.
It strengthens your skills in:

• handling variadic arguments (va_list)
• manual data formatting
• modular and clean C programming
• implementing flags and reproducing standard printf behavior

🧠 Objective

Implement the function:

int ft_printf(const char *format, ...);

This function:

• Prints formatted output to stdout
• Supports several conversion specifiers
• Returns the number of characters printed
• Reproduces the behavior of the original printf for mandatory conversions

🎨 Mandatory Part

✔ Implemented conversions

✔ General rules

• Only write() may be used for printing
• Return value = total printed characters
• %p prints (nil) when the pointer is NULL
• Code must follow the 42 Norm

⭐ Bonus Part

This project implements the bonus flag set allowed by the subject:

✔ Supported flags

✔ Flag rules

• If + and are both used → + wins
• # only affects %x and %X
• # does not add prefix when the number is 0

Other flags such as width, precision, -, 0, and * are not implemented.

🔍 How It Works

1. ft_printf iterates through the format string
2. When it finds %, it checks:
   • flags
   • conversion type
3. It calls helper functions depending on the type
4. It prints numbers, strings, characters, hex, and pointers manually
5. It returns the number of characters printed

Instructions

1. Preparation (Compiling libftprintf.a):

   make all

2. Compilation and Linking:

   # Link main_mandatory.c against libftprintf.a and libft.a
   cc -Wall -Wextra -Werror main_mandatory.c libftprintf.a -I . -L libft -lft -o test_mandatory

3. Execution:

   ./test_mandatory

4. Preparation (Compiling libftprintf.a with Bonus features):

   make bonus

5. Compilation and Linking:

   # Link main_bonus.c against the bonus libftprintf.a and libft.a
   cc -Wall -Wextra -Werror main_bonus.c libftprintf.a -I . -L libft -lft -o test_bonus

6. Execution:

   ./test_bonus

Check for memory leaks:

valgrind --leak-check=full ./test_mandatory
valgrind --leak-check=full ./test_bonus

Clean the project:

make clean
make fclean
make re

Resources

For this project I used the help of some GitBooks from older students, and websites like GeeksforGeeks and W3Schools.