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

int main(void) {
   void* handle;
   void* func;

   handle = dlopen("libssl.so",  RTLD_NOW | RTLD_GLOBAL);
   if (handle) {
      func = dlsym(handle, "CRYPTO_set_id_callback");
      if (!func) {
         printf("error, can't load CRYPTO_set_id_callback\n");
         exit(1);
      } else {
         printf("loaded CRYPTO_set_id_callback\n");
         exit(0);
      }
   } else {
      printf("error, can't open libssl.so: %s\n", dlerror());
      exit(1);
   }
   dlclose(handle); 
   exit(0);
}