Resources
Read or watch:
Secrets of printf
Group Projects concept page (Don’t forget to read this)
Flowcharts concept page
man or help:
printf (3)
Requirements
General
Allowed editors: vi, vim, emacs
All your files will be compiled on Ubuntu 20.04 LTS using gcc, using the options -Wall -Werror -Wextra -pedantic -std=gnu89
All your files should end with a new line
A README.md file, at the root of the folder of the project is mandatory
Your code should use the Betty style. It will be checked using betty-style.pl and betty-doc.pl
You are not allowed to use global variables
No more than 5 functions per file
In the following examples, the main.c files are shown as examples. You can use them to test your functions, but you don’t have to push them to your repo (if you do we won’t take them into account). We will use our own main.c files at compilation. Our main.c files might be different from the one shown in the examples
The prototypes of all your functions should be included in your header file called main.h
Don’t forget to push your header file
All your header files should be include guarded
Note that we will not provide the _putchar function for this project
GitHub
There should be one project repository per group. The other members do not fork or clone the project to ensure only one of the team has the repository in their github account otherwise you risk scoring 0%
More Info
Authorized functions and macros
write (man 2 write)
malloc (man 3 malloc)
free (man 3 free)
va_start (man 3 va_start)
va_end (man 3 va_end)
va_copy (man 3 va_copy)
va_arg (man 3 va_arg)
Compilation
Your code will be compiled this way:
$ gcc -Wall -Werror -Wextra -pedantic -std=gnu89 *.c
As a consequence, be careful not to push any c file containing a main function in the root directory of your project (you could have a test folder containing all your tests files including main functions)
Our main files will include your main header file (main.h): #include main.h
You might want to look at the gcc flag -Wno-format when testing with your _printf and the standard printf. Example of test file that you could use:
alex@ubuntu:~/c/printf$ cat main.c
#include <limits.h>
#include <stdio.h>
#include "main.h"
/**
-
main - Entry point
-
Return: Always 0
*/
int main(void)
{
int len;
int len2;
unsigned int ui;
void *addr;
len = _printf("Let's try to printf a simple sentence.\n");
len2 = printf("Let's try to printf a simple sentence.\n");
ui = (unsigned int)INT_MAX + 1024;
addr = (void *)0x7ffe637541f0;
_printf("Length:[%d, %i]\n", len, len);
printf("Length:[%d, %i]\n", len2, len2);
_printf("Negative:[%d]\n", -762534);
printf("Negative:[%d]\n", -762534);
_printf("Unsigned:[%u]\n", ui);
printf("Unsigned:[%u]\n", ui);
_printf("Unsigned octal:[%o]\n", ui);
printf("Unsigned octal:[%o]\n", ui);
_printf("Unsigned hexadecimal:[%x, %X]\n", ui, ui);
printf("Unsigned hexadecimal:[%x, %X]\n", ui, ui);
_printf("Character:[%c]\n", 'H');
printf("Character:[%c]\n", 'H');
_printf("String:[%s]\n", "I am a string !");
printf("String:[%s]\n", "I am a string !");
_printf("Address:[%p]\n", addr);
printf("Address:[%p]\n", addr);
len = _printf("Percent:[%%]\n");
len2 = printf("Percent:[%%]\n");
_printf("Len:[%d]\n", len);
printf("Len:[%d]\n", len2);
_printf("Unknown:[%r]\n");
printf("Unknown:[%r]\n");
return (0);
}
alex@ubuntu:~/c/printf$ gcc -Wall -Wextra -Werror -pedantic -std=gnu89 -Wno-format *.c
alex@ubuntu:~/c/printf$ ./printf
Let's try to printf a simple sentence.
Let's try to printf a simple sentence.
Length:[39, 39]
Length:[39, 39]
Negative:[-762534]
Negative:[-762534]
Unsigned:[2147484671]
Unsigned:[2147484671]
Unsigned octal:[20000001777]
Unsigned octal:[20000001777]
Unsigned hexadecimal:[800003ff, 800003FF]
Unsigned hexadecimal:[800003ff, 800003FF]
Character:[H]
Character:[H]
String:[I am a string !]
String:[I am a string !]
Address:[0x7ffe637541f0]
Address:[0x7ffe637541f0]
Percent:[%]
Percent:[%]
Len:[12]
Len:[12]
Unknown:[%r]
Unknown:[%r]
alex@ubuntu:~/c/printf$
We strongly encourage you to work all together on a set of tests
If the task does not specify what to do with an edge case, do the same as printf
Copyright - Plagiarism
You are tasked to come up with solutions for the tasks below yourself to meet with the above learning objectives.
You will not be able to meet the objectives of this or any following project by copying and pasting someone else’s work.
You are not allowed to publish any content of this project.
Any form of plagiarism is strictly forbidden and will result in removal from the program.
Tasks
- I'm not going anywhere. You can print that wherever you want to. I'm here and I'm a Spur for life
mandatory
Score: 0.0% (Checks completed: 0.0%)
Write a function that produces output according to a format.
Prototype: int _printf(const char *format, ...);
Returns: the number of characters printed (excluding the null byte used to end output to strings)
write output to stdout, the standard output stream
format is a character string. The format string is composed of zero or more directives. See man 3 printf for more detail. You need to handle the following conversion specifiers:
c
s
%
You don’t have to reproduce the buffer handling of the C library printf function
You don’t have to handle the flag characters
You don’t have to handle field width
You don’t have to handle precision
You don’t have to handle the length modifiers
Repo:
GitHub repository: printf
- Education is when you read the fine print. Experience is what you get if you don't
mandatory
Score: 0.0% (Checks completed: 0.0%)
Handle the following conversion specifiers:
d
i
You don’t have to handle the flag characters
You don’t have to handle field width
You don’t have to handle precision
You don’t have to handle the length modifiers
Repo:
GitHub repository: printf contributors: mendy-tech contributors: Naftali Budamba