title: Linux WiFI AP : refresh `iw dev wlan0 station dump` output (inactive time)
body: <ul>
  <li>I have a Linux (3.14.36) embedded board acting as a WiFi AP. </li>
  <li>The WiFi chipset doesn't support monitoring mode.</li>
  <li>My laptop(the client) is connected to this board by WiFi</li>
  <li>The WiFi AP is acting as a network bridge to another computer, and doesn't provide an IP adress to the client (the WiFi AP only has the MAC address of the client)</li>
  </ul>
  
  <p>I want to monitor the signal strengh of the connection WiFi AP &lt;-> Client and be able to trigger a "refresh" of the signal strengh value.</p>
  
  <p>Doing : <code>iw dev wlan0 station dump</code> gives me : </p>
  
  <pre><code>Station xx:xx:xx:xx:xx:xx (on wlan0)
      inactive time:  123820 ms // &lt;-- The problem
      rx bytes:   10291
      rx packets: 60
      ...
      signal:     -65 dBm // What I want to refresh
      ...
  </code></pre>
  
  <p>I understood that the signal strengh is updated every time there is a network activity. (So, in the example above, it has been refreshed 123s ago).</p>
  
  <p>How can I force a refresh of this value ? (By forcing the AP to send "something" to the client for example) Knowing that the board/WiFi driver/WiFi device doesn't support tools such as iwconfig</p>