title: What is meaning of the '_attribute_((aligned(4)));' in the first line?
body: <pre><code>char buf[BUF_LEN]_attribute_((aligned(4)));
  ssize_t len, i = 0;
  /* read BUF_LEN bytes' worth of events */
  len = read (fd, buf, BUF_LEN);
  /* loop over every read event until none remain */
  while (i &lt; len) {
  struct inotify_event *event =
  (struct inotify_event *) &amp;buf[i];
  Monitoring File Events | 239
  printf ("wd=%d mask=%d cookie=%d len=%d dir=%s\n",
  event-&gt;wd, event-&gt;mask,
  event-&gt;cookie, event-&gt;len,
  (event-&gt;mask &amp; IN_ISDIR) ? "yes" : "no");
  /* if there is a name, print it */
  if (event-&gt;len)
  printf ("name=%s\n", event-&gt;name);
  /* update the index to the start of the next event */
  i += sizeof (struct inotify_event) + event-&gt;len;
  }
  </code></pre>