In order to use any service remote Bluetooth device need to send Service Search and Service Attribute or Service Search Attribute request over Bluetooth L2CAP connection on SDP PSM (0x0001). The sdpd daemon will try to find matching Service Record in its Service Database and will send appropriate response back. The remote device then will process the response, extract all required information and will make a separate connection in order to use the service.
Bluetooth applications, running on the host, register services with the local sdpd daemon. Operation like service registration, service removal and service change are performed over the control socket. It is possible to query entire content of the sdpd Service Database with sdpquery(1) by issuing browse command on the control socket.
The command line options are as follows:
/var/run/sdp
.
_sdpd
''.
_sdpd
''.
In case of multiple Bluetooth devices connected to the same host it is possible to specify which services should be ``bound'' to which Bluetooth device. Such assignment should be done at service registration time.
Requests to register, remove or change service can only be made via the control socket. The sdpd daemon will check the peer's credentials and will only accept the request when the peer is the superuser, of if the peer is a member of the group specified with the -G option.
The sdpd daemon does not check for duplicated Service Records. It only performs minimal checking on the service data sent in the Service Register request. It is assumed that application must obtain all required resources such as RFCOMM channels etc., before registering the service.
/var/run/sdp