undefined reference to 'dlopen'

I'm trying to load a .so file, but this title error is showing up. Can anyone help me?

    #include <iostream>
    #include <dlfcn.h>
    #include <stdio.h>

    using namespace std;

    int main()
    {
      void *abrir;
      abrir = dlopen("EZClient.so", RTLD_NOW);

    if(!abrir)
    {
      printf("%s\n", dlerror());
      return -1;
    }
    return 0;
    }