The system call "Hello World"

In our docker image, we have a system call that prints "Hello World"  from the kernel space.
Its code is in:
~/Downloads/pcs3746-sistemas-operacionais/1/linux/sys_hello_world$ ls
built-in.o  Makefile  modules.builtin  modules.order  sys_hello_world.c  sys_hello_world.o
Modify it: change the string to print. That is your first modification in a kernel!
Make init.c as in:
~/Downloads/pcs3746-sistemas-operacionais/1/initramfs$ more init.c
#include "hello_world.h"

int main()
{
   while (1) {
      hello_world();
   }
   return 0;
}
This will make a lot of messages from the kernel in your terminal.
When you run it through:
~/Downloads/pcs3746-sistemas-operacionais/1$ ./run.sh 
the kernel and rootfs are remade.

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