title: bluetooth rfcomm dies after reading first chunk
body: <p>Hello I am trying to read data from a Sensor (Sensaris Sensopod) over bluetooth and I face the below problem:
  After lot of tries I managed to connect using:</p>
  
  <pre><code>hciconfig hci0 sspmode 1
  sdptool add SP
  rfcomm connect /dev/rfcomm0 xx:xx:xx:xx:xx:xx 1 &amp;
  </code></pre>
  
  <p>and then I use </p>
  
  <pre><code>cat /dev/rfcomm0
  </code></pre>
  
  <p>and I get around 30 lines of data and then it simply does nothing. When I close it using ^c and I try the cat again it's showing nothing again (command stays open)</p>
  
  <p>I tried it on Xubuntu and Rasbian (Rpi) and got the same results</p>