diff --git a/docs/examples/smtp-mail.c b/docs/examples/smtp-mail.c
index ed9524e877efb5c36e193a6c2f4d723485871d4e..af4d1b65b119e365c77a55cf2ae6096628287dd4 100644
--- a/docs/examples/smtp-mail.c
+++ b/docs/examples/smtp-mail.c
@@ -133,5 +133,5 @@ int main(void)
     curl_easy_cleanup(curl);
   }
 
-  return 0;
+  return (int)res;
 }