diff --git a/neighbor.cpp b/neighbor.cpp
index f43eea6..64aac5a 100644
--- a/neighbor.cpp
+++ b/neighbor.cpp
@@ -181,7 +181,7 @@ QString Neighbor::macOfIP(QString ip, bool *ok) const {
   nl_cache_free(neigh_cache);
   nl_socket_free(sock);
 
-  if(mac == NULL || count == 0) {
+  if(mac[0] == '\0' || count == 0) {
     if(ok != NULL) {
       *ok = true;
     }