minor corrections

docs/ares_set_notify_pending_write_callback.3

@@ -28,7 +28,7 @@ function \fIcallback\fP in the given ares channel handle \fIchannel\fP that
 is invoked whenever there is new pending TCP data to be written.  Since TCP
 is stream based, if there are multiple queries being enqueued back to back they
 can be sent as one large buffer. Normally a \fBsend(2)\fP syscall operation
-would triggered for each query.
+would be triggered for each query.
 
 When setting this callback, an event will be triggered when data is buffered,
 but not written.  This event is used to wake the caller's event loop which

src/lib/ares_process.c

@@ -274,6 +274,11 @@ static void write_tcp_data(ares_channel_t *channel, fd_set *write_fds,
 {
   ares__slist_node_t *node;
 
+  /* no possible action */
+  if (write_fds == NULL && write_fd == ARES_SOCKET_BAD) {
+    return;
+  }
+
   for (node = ares__slist_node_first(channel->servers); node != NULL;
        node = ares__slist_node_next(node)) {
     ares_server_t *server = ares__slist_node_val(node);