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

volatile sig_atomic_t sigpipe_received = 0;

void sigpipe_handler(int sig) {
   sigpipe_received = 1;
}

enum {PIPE_READ = 0, PIPE_WRITE = 1};
int main() {
   int pipefds[2];
   if (pipe(pipefds) < 0) {
      perror("pipe"); exit(1);
   }
   pid_t child = fork();
   if (child < 0) {
      perror("fork"); exit(1);
   }
   if (child == 0) {
      close(pipefds[PIPE_WRITE]);
      char buf[32];
      ssize_t nbytes = read(pipefds[PIPE_READ],
            buf, sizeof buf);
      if (nbytes > 0) {
         if (write(1, buf, nbytes) < nbytes) exit(1);
      }
      exit(0);
   }
   close(pipefds[PIPE_READ]);
   sigignore(SIGPIPE);
   ssize_t nbytes;
   do {
      const char message[] = "Hello!\n";
      nbytes = write(pipefds[PIPE_WRITE],
         message, sizeof message - 1);
   } while (nbytes > 0);
   if (errno != EPIPE) perror("write");
   close(pipefds[PIPE_WRITE]);
   wait(0);
}