1  #include <dlfcn.h>
       2  #include <stdio.h>
       3  
       4  int
       5  foo (int i)
       6  {
       7    if (dlsym (RTLD_DEFAULT, "unload7_nonexistent_symbol") == NULL)
       8      return 1;
       9    puts ("dlsym returned non-NULL");
      10    return 0;
      11  }