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


int main(void)
{
  pid_t pid;
  pid = fork();
  if (pid < 0)
  {
    printf("fork is error\n");
    return -1;
  }
  // 父进程
  if (pid > 0) {
    printf("This is parent, parent pid is %d\n",getppid());
  }
  // 子进程
  if (pid == 0){
    printf("This is child, child pid is %d\n",getpid());
  }
  return 0;
}