Your program contains 3 files: info.h, info.c, main.c. You also added a correct makefile. if you did some changes on the file main.c only after the first execution of command (make). What is the output of executing the command ( make ) again gec c main.c gccc info.c gece main.c gcc info.o main.0 =0 project gcc info.o main.o -o project gcc-main.c gcc info.o main.o -o project