#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

int main(void)
{
  pid_t child;
  if((child = fork()) == -1)
  {
    perror("fork");
    exit(EXIT_FAILURE);
  }
  else if(child == 0)
  {
    puts("in child");
    printf("\tchild pid = %d\n", getpid());
    printf("\tchild ppid = %d\n", getppid());
    exit(EXIT_SUCCESS);
  }
  else
  {
    puts("in parent");
    printf("\tparent pid = %d\n", getpid());
    printf("\tparent ppid = %d\n", getppid());
  }
  exit(EXIT_SUCCESS);
}