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

---

Description

ft_printf is a project that involves recoding the standard C library's printf function. The primary goal of this project is to understand the mechanics of variadic functions in C and to build an efficient data formatting system. The project supports the following conversion specifiers: %c, %s, %p, %d, %i, %u, %x, %X, and %%.

Instructions

Compilation

The project is compiled using the Makefile located in the root directory. You can use the following commands:

• make: Compiles the source files and creates the libftprintf.a library.
• make clean: Removes the object (.o) files.
• make fclean: Removes object files and the generated library file.
• make re: Cleans and recompiles the entire project.

Execution

To include the libftprintf.a library in your own project:

1. Include the ft_printf.h header file in your code.
2. Link the library during compilation:

cc main.c libftprintf.a -o my_program

Resources

• Man Pages: man 3 printf, man 3 stdarg.
• Documentation: C Variadic Functions (gnu.org).
• Reference: Standard C Library documentation regarding write and va_list.

AI Usage

In this project, Artificial Intelligence (Gemini) was utilized for the following tasks:

• Debugging: Identifying and resolving memory access issues (potential buffer overflows) and handling NULL pointer cases (specifically the (nil) output for %p).
• Documentation: Structuring this README file and refining technical explanations according to 42 requirements.

Algorithm and Data Structure

The project is built on an algorithm that parses the format string in a single pass.

1. Traversal: The format string is scanned character by character using a while loop.
2. Detection: When a % character is encountered, the next character is checked to see if it is a valid conversion specifier.
3. Dispatching: Based on the specifier, the corresponding data type is fetched from the stack using the va_arg macro.
4. Recursive Conversion: Recursive functions are used for hexadecimal and integer conversions. This allows digits to be printed directly to the standard output without the need for a temporary buffer, ensuring memory efficiency.
5. Counter: Every successful write operation is added to the check counter, which serves as the function's total return value.