anchor.diff:      {"c_int", "enif_is_exception", "arg1: *mut ErlNifEnv, term: ERL_NIF_TERM"},
       {"c_int", "enif_make_reverse_list", "arg1: *mut ErlNifEnv, term: ERL_NIF_TERM, list: *mut ERL_NIF_TERM"},
       {"c_int", "enif_is_number", "arg1: *mut ErlNifEnv, term: ERL_NIF_TERM"},
  -    {"*mut c_void", "enif_dlopen", "lib: *const c_uchar, err_handler: Option<extern \"C\" fn (arg1: *mut c_void, arg2: *const c_uchar)>, err_arg: *mut c_void"},
  -    {"*mut c_void", "enif_dlsym", "handle: *mut c_void, symbol: *const c_uchar, err_handler: Option<extern \"C\" fn (arg1: *mut c_void, arg2: *const c_uchar)>, err_arg: *mut c_void"},
  +    {"*mut c_void", "enif_dlopen", "lib: *const c_uchar, err_handler: Option<unsafe extern \"C\" fn (arg1: *mut c_void, arg2: *const c_uchar)>, err_arg: *mut c_void"},
  +    {"*mut c_void", "enif_dlsym", "handle: *mut c_void, symbol: *const c_uchar, err_handler: Option<unsafe extern \"C\" fn (arg1: *mut c_void, arg2: *const c_uchar)>, err_arg: *mut c_void"},
       {"c_int", "enif_consume_timeslice", "arg1: *mut ErlNifEnv, percent: c_int"},
       {"c_int", "enif_is_map", "env: *mut ErlNifEnv, term: ERL_NIF_TERM"},
       {"c_int", "enif_get_map_size", "env: *mut ErlNifEnv, term: ERL_NIF_TERM, size: *mut size_t"},
  
positive.code:     {"ERL_NIF_TERM", "enif_make_tuple_from_array", "arg1: *mut ErlNifEnv, arr: *const ERL_NIF_TERM, cnt: c_uint"},
      {"ERL_NIF_TERM", "enif_make_list_from_array", "arg1: *mut ErlNifEnv, arr: *const ERL_NIF_TERM, cnt: c_uint"},
      {"c_int", "enif_is_empty_list", "arg1: *mut ErlNifEnv, term: ERL_NIF_TERM"},
      {"*const ErlNifResourceType", "enif_open_resource_type", "arg1: *mut ErlNifEnv, module_str: *const c_uchar, name_str: *const c_uchar, dtor: Option<extern \"C\" fn (arg1: *mut ErlNifEnv, arg2: *mut c_void)>, flags: ErlNifResourceFlags, tried: *mut ErlNifResourceFlags"},
      {"*mut c_void", "enif_alloc_resource", "_type: *const ErlNifResourceType, size: size_t"},
      {"", "enif_release_resource", "obj: *const c_void"},
      {"ERL_NIF_TERM", "enif_make_resource", "arg1: *mut ErlNifEnv, obj: *const c_void"},
  
negative.code:     {"c_int", "enif_map_iterator_next", "env: *mut ErlNifEnv, iter: *mut ErlNifMapIterator"},
      {"c_int", "enif_map_iterator_prev", "env: *mut ErlNifEnv, iter: *mut ErlNifMapIterator"},
      {"c_int", "enif_map_iterator_get_pair", "env: *mut ErlNifEnv, iter: *mut ErlNifMapIterator, key: *mut ERL_NIF_TERM, value: *mut ERL_NIF_TERM"},
      {"ERL_NIF_TERM", "enif_schedule_nif", "env: *mut ErlNifEnv, fun_name: *const c_uchar, flags:c_int, dtor: Option<unsafe extern \"C\" fn(env: *mut ErlNifEnv, argc:c_int, argv:*const ERL_NIF_TERM)>, argc:c_int, argv:*const ERL_NIF_TERM"}
      ] ++
  
  
  