Holberton School – printf

This repository contains our C implementation of a custom _printf function for the Holberton School C - printf project. The goal is to understand how printf works under the hood by handling format parsing, variadic arguments, and printing different data types using write().

Requirements

• OS: Ubuntu 20.04 LTS
• Compiler: gcc
• Flags: -Wall -Werror -Wextra -pedantic -std=gnu89 -Wno-format
• Style: Betty
• No global variables
• Max 5 functions per file
• No main.c files in the project root (keep tests in a separate folder)

Authorized Functions / Macros

• write
• malloc, free
• va_start, va_end, va_copy, va_arg

Files

• main.h — prototypes, structs, and macros
• _printf.c — main entry point (format parsing + dispatch)
• parse.c / handle.c — helpers for parsing and selecting handlers
• buffer.c — buffered writing helpers (if used)
• print_basic.c — printing for basic specifiers (c, s, %)
• print_int.c — printing for integers (d, i, u, o, x, X, etc.)
• print_pointer.c — printing for pointers (p)
• print_custom.c — custom/advanced specifiers (project advanced tasks)
• utils.c — shared helpers (length, conversions, etc.)
• man_3_printf — manual page for _printf

Supported Format Specifiers

Minimum required:

• %c — character
• %s — string
• %% — percent sign

Project includes additional specifiers from later tasks (like d/i, u, o, x/X, b, p, r, R, S, + flags, etc.), depending on the task level completed in the repository.

Compilation

gcc -Wall -Werror -Wextra -pedantic -std=gnu89 -Wno-format *.c -o printf

Usage

Example test file:

#include <stdio.h>
#include "main.h"

int main(void)
{
    _printf("Hello %s!\n", "world");
    _printf("Number: %d\n", 42);
    _printf("Percent: %%\n");
    return (0);
}

Compile and run:

gcc -Wall -Werror -Wextra -pedantic -std=gnu89 -Wno-format *.c main.c -o test
./test

Authors

Aliyyiakbar Shirinli

Amal Shafiyev