printf is a weel known function used in C programming to do formated printing. Usually it only takes the standard library to call it into a c program, and using it for simple strings or formatted specifiers that allow us to print diferent types of data. This time we are presenting a printf project made from scratch in most of its features in order to understand the complexity of a powerful tool. You can see man 3 of printf to understand how _printf works.
$ gcc -Wall -Werror -Wextra -pedantic *.c
int _printf(const char *format, ...)
| Specifiers | Description |
|---|---|
| %c | Print single character |
| %s | Print string of characteres |
| %d | Print decimal numbers |
| %i | Print integers |
| File | Description |
|---|---|
| holberton.h | Header file Include all function prototypes Include structure of specifiers |
| printf.c | Project function: _printf Start the variadic list. Iterates string format of entry and check for a moldule symbol (%) . If the symbol is found then check if the next char match with one of the valid specifiers in the structure using the auxiliar function to comapare ( comp), in that case the respective function of these format is called. For the characters that doesn't match any of the formats the function ignores the module symbole and print it as a string. In case that the module symbole is not found, print the each character normally. |
| printf_functions.c | Auxiliar functions _putchar: using write function, prints a character printc: print character using list variable. print_string: pint strings, if string is null it pirnts (null) print_n: print numbers base 10. |
Mauricio Garcia - @camagar
Valentina Jaramillo - @valen2510