rfcomm bluetooth permission denied error raspberry pi

Question

I\'m using a bluetooth dongle to try and send information from ubuntu 15.04 to raspberry pi b+ running the latest debian jessie image. I\'m just following the http://people.csai

Answer 1

Running your script as root kinda works, but it's not a good practice.

According to this thread, you just need to adjust permissions to the /var/run/sdp file (which is created when using the --compat switch).

So, to prevent link rot I'm reproducing dlech's post and adapting it to Raspberry Pi:

1. make sure your pi user is in the bluetooth group:

   $ cat /etc/group | grep bluetooth
   bluetooth:x:113:pi
   

   1.1. If it's not, add pi to bluetooth group:

   $ sudo usermod -G bluetooth -a pi
   

2. Change group of the /var/run/sdp file:

   $ sudo chgrp bluetooth /var/run/sdp
   

3. To make the change persistent after reboot:

   3.1. Create file /etc/systemd/system/var-run-sdp.path with the following content:

   [Unit]
   Descrption=Monitor /var/run/sdp
   
   [Install]
   WantedBy=bluetooth.service
   
   [Path]
   PathExists=/var/run/sdp
   Unit=var-run-sdp.service
   

   3.2. And another file, /etc/systemd/system/var-run-sdp.service:

   [Unit]
   Description=Set permission of /var/run/sdp
   
   [Install]
   RequiredBy=var-run-sdp.path
   
   [Service]
   Type=simple
   ExecStart=/bin/chgrp bluetooth /var/run/sdp
   

   3.3. Finally, start it all up:

   sudo systemctl daemon-reload
   sudo systemctl enable var-run-sdp.path
   sudo systemctl enable var-run-sdp.service
   sudo systemctl start var-run-sdp.path
   

Credit goes to user dlech who "figured it out" originally.