#include <unistd.h>
#include <stdio.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <signal.h>

int main(void)
{
   pid_t pid = fork();
   if (pid < 0){
   	  perror("I am the parent and fork() failed");

   } else if (pid != 0) {
	  
      printf("I am the parent.\n");
      printf("P: my pid is %d.\n", getpid());
      printf("P: my child is %d.\n", pid);
      printf("P: my parent is %d.\n", getppid());
      sleep(5);
   }
   else {
   
      printf("I am the child.\n");
      printf("C: my pid is %d.\n", getpid());
      printf("C: my parent is %d.\n", getppid());
      sleep(5);
   }
   return 0;
}