EntryPointNotFoundException - .so plugin (Linux)

I’m trying to use a .so plugin which I compiled using Linux but i keep getting EntryPointNotFoundException

Here’s a sample of the c++ code.

cpp:

#include <rosgraph_msgs/Clock.h>
#include <unistd.h>
#include <thread>
#include "ros_interface.hpp"
#include "node.hpp"

// Default initializer
ros_interface::ros_interface() {
    // NOP
}

// Initialize the ROS communication interface
ros_interface::ros_interface(int argc, char** argv, string node_name) {
    // ROS initialization
    ros::init(argc,argv,node_name);

    // Set the time simulation as in "/clock"
    system("rosparam set /use_sim_time true");

    // Initialize the pointer to clocker
    c = new clocker;

    // Set publisher on clocker
    c->pub_clock = c->nh.advertise<rosgraph_msgs::Clock>("/clock",1);

}

// Destructor
ros_interface::~ros_interface() {
    // Delete all node pointers in nodes_ptr
    for(auto x : nodes_ptr) delete *((node**) x);

    // Delete clock struct pointer
    delete(c);
}

extern "C" void initialize() {
    instance = new ros_interface(0, 0, "instance");
}

// Lots of other stuff

And the hpp:

#ifndef ROS_INTERFACE_H
#define ROS_INTERFACE_H

#include <string>
#include <vector>

// Position data type
struct position {
    double x;       // position in x
    double y;       // position in y
    double z;       // position in z
    double roll;    // lateral axis (X)
    double pitch;   // longitudinal axis (Y)
    double yaw;     // vertical axis (Z)
};

// Velocity data type
struct velocity {
    double x;       // velocity in x
    double y;       // velocity in y
    double z;       // velocity in z
    double roll;    // lateral axis angular velocity
    double pitch;   // longitudinal axis angular velocity
    double yaw;     // vertical axis angular velocity
};

extern "C" void initialize(); 
extern "C" void addNode(int id, int type, std::string target, position init_pose); 
extern "C" void setVelocity(int id, velocity msg); 
extern "C" position getPos(int id); 
extern "C" void setClock(float dt); 
extern "C" bool rosOk(); 

// Node class to ROS interface
class ros_interface {
public:
    // Default initializer
    ros_interface();

    // Initialize the ROS communication interface
    ros_interface(int argc, char** argv, std::string node_name);

    // Destructor
    ~ros_interface();

// And more stuff...

And here’s the c# code used in unity:

    [DllImport("ros_interface")]
    private static extern void initialize();

    [DllImport("ros_interface")]
    private static extern void addNode(int id, int type, string target, Pose init_pose);

    [DllImport("ros_interface")]
    private static extern void setVelocity(int id, Pose p);

    [DllImport("ros_interface")]
    private static extern bool rosOk();


    // Use this for initialization
    void Start()
    {
        initialize();
    }

I build it sucessfully with unity and then run it on linux, but i get the following error when calling the initialize method:

EntryPointNotFoundException: initialize

I did some research, this error means that the initialize method was not found on the plugin, but the method seems to be there and I haven’t found a solution. The same error will pop if I try to call any of the methods from the .so plugin.

What can I do to make this plugin work?

Did you resolve this? I also got the same error.