[USER] System calls

init/init.c

@@ -1,8 +1,10 @@
+#include <stdio.h>
+#include <unistd.h>
 int main(int argc, char **argv)
 {
   (void) argc;
   (void) argv;
-  int i=0;
-  for(;;)i++;
+  asm("syscall" :: "a" (0x3FF), "D" ("Hello, world!\n"));
+  for(;;);
   return 0;
 }