epoll.7: Fix error handling after accept() in example code

Simply continuing after an error is in most cases wrong,
and can lead to infinite loops (e.g., for EMFILE).
So handle an error by terminating.

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=504202

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Reported-by: Olaf van der Spek <olafvdspek@gmail.com>

man7/epoll.7

@@ -227,7 +227,7 @@ for (;;) {
                             (struct sockaddr *) &local, &addrlen);
             if (conn_sock == \-1) {
                 perror("accept");
-                continue;
+                exit(EXIT_FAILURE);
             }
             setnonblocking(conn_sock);
             ev.events = EPOLLIN | EPOLLET;