Libft is a open source C library, with several function to help all kinds of projects in development. This is a very well organized and more completed version of the Ecole 42 libft project.
Read: Libft Wiki
First clone the repository:
git clone http://github.com/LuigiEnzoFerrari/42School_Libft libft
Then use command make inside the libft repository to generate a libft.a file.
make -C <libft-path>
Now you have a static library .a with all functions from the libft. Now you can compile your project with the static library.
First include the libft.h on your .c file.
#include <libft.h>
Then compile your project like the example below:
clang main.c -I <libft-path> -L <libft.a-path> -lft
To clean the .o files use the command make clean.
make clean -C <libft-path>