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cbluetoothraspberry-piclionbluez

Multiplatform C BLE dependency issue

I am building an app using bluez in C.

I am using CLion as my dev environment with two targets - A raspberry Pi 4B and my Linux machine.

This is my CMakeLists.txt

cmake_minimum_required(VERSION 3.13)
project(bluetooth_client C)

set(CMAKE_C_STANDARD 11)

set (CMAKE_C_FLAGS "-lbluetooth")
add_executable(bluetooth_client main.c)

When I run this targeting the raspberry pi (aka remote host), it works fine. When I run it targeting the local host (Linux on intel) it shows this build message: enter image description here

I tried to verify if I have the exact libraries installed. When I edit code while targeting the Linux dev it correctly sees all the Bluetooth libraries (bluetooth/hci/hci_lib).

The code I run is from Edison-Playground

Solution

  • set (CMAKE_C_FLAGS "-lbluetooth") is putting the library before the executable, which results in an invalid order and linker doesn't find your symbol.

    Do not use CMAKE_C_FLAGS directly at all, forget it exists - use various add_* facilities instead, like add_compile_options, add_link_options. Use target_link_libraries(bluetooth_client PRIVATE bluetooth) for linking.