-pn_connection_t *conn = NULL;
-pn_link_t *sender = NULL;
-pn_proactor_t *proactor = NULL;
-pthread_mutex_t send_lock;
-cd_message_list_t out_messages;
-uint64_t cd_tag = 1;
-uint64_t acknowledged = 0;
-amqp1_config_transport_t *transport = NULL;
-
+static pn_connection_t *conn = NULL;
+static pn_link_t *sender = NULL;
+static pn_proactor_t *proactor = NULL;
+static pthread_mutex_t send_lock;
+static cd_message_list_t out_messages;
+static uint64_t cd_tag = 1;
+static uint64_t acknowledged = 0;
+static amqp1_config_transport_t *transport = NULL;