This required option specifies the address of the remote RFCOMM server. The address can be specified as BD_ADDR or name. If name was specified then the rfcomm_sppd utility will attempt to resolve the name via bt_gethostbyname(3).
-b
Detach from the controlling terminal, i.e., run in background.
-c channel
This option specifies RFCOMM channel to connect to. The channel must provide Serial Port service. If channel was not specified then rfcomm_sppd utility will try to obtain RFCOMM channel via Service Discovery Protocol from the server.
-h
Display usage message and exit.
-t tty
Slave pseudo tty name. If not set stdin/stdout will be used. This option is required if -b option was specified.