BlueZ
SDP Search via BlueZ
On Linux, Qt Bluetooth uses a separate executable, sdpscanner, to integrate with the official Linux Bluetooth protocol stack (BlueZ). The usage is limited to service discovery via SDP. The Qt Bluetooth library itself does NOT link against BlueZ. Communication between sdpscanner and QtBluetooth happens via stdin/stdout. Therefore QtBluetooth and user code linking to it is not considered a derivative work, and does not have to be released under GPL too.
The sources can be found in qt5/qtconnectivity/src/tools/sdpscanner.
Copyright (C) 2000-2016 BlueZ Project.