diff --git a/agent/gpg-agent.c b/agent/gpg-agent.c
index 5305098d2..c4b281d63 100644
--- a/agent/gpg-agent.c
+++ b/agent/gpg-agent.c
@@ -1518,6 +1518,7 @@ main (int argc, char **argv)
                      strerror (errno) );
           agent_exit (1);
         }
+      ctrl->thread_startup.fd = GNUPG_INVALID_FD;
       ctrl->session_env = session_env_new ();
       if (!ctrl->session_env)
         {