/* Demonstrate what happens when the Parent gets killed (Q5.e Midterm) */
#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

main(argc,argv)
int argc;
char *argv[];
{pid_t IsParent;
 int ReadError=1,Pipefd[2],N;
 div_t Result;
 printf("!\n"); 
 pipe(Pipefd);
 IsParent=fork();
 if (IsParent) {
  dup2(Pipefd[1],1);
  close(Pipefd[1]);
  close(Pipefd[0]);
  N=0;
  while (1) {
   write(1,&N,sizeof(int));  /* Continually write Numbers to the Pipe */
   Result=div(N++,10);
   fprintf(stderr,"Just sent %d Down the Pipe",N);
   sleep(1);
  }
 }
 else { /* Child receives thru the pipe */
  dup2(Pipefd[0],0);
  close(Pipefd[1]);
  close(Pipefd[0]);
  while (ReadError) {
   if ((ReadError=read(0,&N,sizeof(int)))<0){   /* Continually write Numbers to the Pipe */
    perror("Got a -1");
    exit(1);
   }
   Result=div(N,10);
   fprintf(stderr,"Received %d From the Pipe - Read Result: %d\n",N,ReadError);
   if (N==5) 
    kill(getppid(),9);
   sleep(2);	/* Slow Things Down */
  }
 }
}