How to use the .so file in my project？

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I followed the "beginner tutorial" to study the ROS, now I want to build a new project which communicates with the robot by using the Serial Port. I searched the packages and found the "cereal_port", I downloaded the source , compiled and got the "libcereal_port.so" file. I used the Eclipse to develop the code and tried to find how to use the .so file in Eclipse, however, I added the .so in the /lib and modified the project configuration which added the file as a library, it can't be found, the "#include <cereal_port cerealport.h="">" gave an error.

Could anyone please help me?