Printf Project

Printf is a function that prints an entry string with based format specifiers, is often used to manipulating data before to print on screen.

The objetive of this project is recreate the function as _printf without using the standard libraries using C as programing language.

Requirements

General

• Allowed editors: vi, vim, emacs
• All files will be compiled using gcc, using the options -Wall -Werror -Wextra -pedantic -std=gnu89
• All files should end with a new line
• A README.md file, at the root of the folder of the project is mandatory
• Code should use the Betty style. It will be checked using betty-style.pl and betty-doc.pl
• Global variables are not allowed
• No more than 5 functions per file
• The prototypes of all functions should be included in on header file called main.h
• All header files should be include guarded

Functions and Macros will be used

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

Common Usage

_printf(const char * format, ...);

As we could see on the previous prototype we have a const char * format that is an entry string with the format inside to analyze.

Also we have a ... which is related as an infinite arguments that our function could have. These last ones will replace in our string the space where %Format_Specifier is called.

Specifiers Usage

%C

The specifier %c replaces the space with a Character defined on the function as an argument. An example structure of usage:

_printf("%c", Input Character);

As result:

_printf ("My input char is: %c", 'H');

On screen:

My input char is: H

%S

The specifier %s replaces the space with a String defined on the function as an argument. An example structure of usage:

_printf("%s", Input string);

As result:

_printf ("Hello %s", "World");

On screen:

Hello World

%i

The specifier %i replaces the space with an integer defined on the function as an argument. An example structure of usage:

_printf("%i", Input integer);

As result:

_printf ("My new int is: %i", 10);

On screen:

My new int is: 10

Flow Chart

Credits && Docs

Secrets of “printf” by Professor Don Colton

Based on the Project # 0x11. C - printf on Holberton School

Command man printf and printf function by David MacKenzie