#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <poll.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>

#define CHECK(OP) check(#OP, OP)

static int check(const char *what, int n) {
  if(n < 0) {
    perror(what);
    exit(EXIT_FAILURE);
  }
  return n;
}

static void pollit(const char *what, int fd) {
  struct pollfd ufd;
  int n;
  char buf[1];

  memset(&ufd, 0, sizeof ufd);
  ufd.fd = fd;
  ufd.events = POLLIN;
  CHECK(poll(&ufd, 1, 1000));
  switch(ufd.revents & (POLLIN|POLLHUP)) {
  case POLLIN: printf("%s: POLLIN\n", what); break;
  case POLLHUP: printf("%s: POLLHUP\n", what); break;
  case POLLIN|POLLHUP: printf("%s: POLLIN|POLLHUP\n", what); break;
  case POLLERR: printf("%s: POLLERR\n", what); break;
  default: printf("%s: %#x\n", what, (unsigned)ufd.revents); break;
  }
  CHECK(fcntl(fd, F_SETFL, O_NONBLOCK | fcntl(fd, F_GETFL)));
  n = read(fd, buf, 1);
  if(n != 0)
    printf("%s: wasn't at EOF after all (%d, %d=\"%s\")\n",
	   what, n, errno, strerror(errno));
}

int main(void) {
  int p[2], fd;

  system("uname -a");
  CHECK(pipe(p));
  CHECK(close(p[1]));
  pollit("pipe", p[0]);
  CHECK(socketpair(PF_UNIX, SOCK_STREAM, 0, p));
  CHECK(close(p[1]));
  pollit("socketpair", p[0]);
  CHECK(socketpair(PF_UNIX, SOCK_STREAM, 0, p));
  CHECK(shutdown(p[1], SHUT_WR));
  pollit("SHUT_WR socketpair", p[0]);
  CHECK(socketpair(PF_UNIX, SOCK_STREAM, 0, p));
  CHECK(shutdown(p[0], SHUT_RD));
  pollit("SHUT_RD socketpair", p[0]);
  unlink("poll-test-tmp");
  CHECK((fd = open("poll-test-tmp", O_CREAT|O_EXCL|O_RDWR, 0600)));
  pollit("regular", fd);
  return 0;
}

/*
Local Variables:
c-basic-offset:2
comment-column:40
End:
*/