diff --git a/cpp/httpclientpool.cc b/cpp/httpclientpool.cc
index 9703304..0734db6 100644
--- a/cpp/httpclientpool.cc
+++ b/cpp/httpclientpool.cc
@@ -258,6 +258,7 @@ namespace f8
 
         static int HandleSocket(CURL *easy, curl_socket_t s, int action, void *userp, void *socketp)
         {
+            return 0;
         }
 
         static void StartTimeout(CURLM *multi, long timeout_ms, void *userp)