diff --git a/daemon/worker.c b/daemon/worker.c
index 9512f447c..d0e276c57 100644
--- a/daemon/worker.c
+++ b/daemon/worker.c
@@ -999,7 +999,7 @@ worker_init(struct worker* worker, struct config_file *cfg,
 	if(worker->thread_num != 0) {
 		/* start listening to commands */
 		if(!tube_listen_cmd(worker->cmd, worker->base,
-			cfg->msg_buffer_size, worker_handle_control_cmd,
+			cfg->msg_buffer_size, &worker_handle_control_cmd,
 			worker)) {
 			log_err("could not create control compt.");
 			worker_delete(worker);
diff --git a/daemon/worker.h b/daemon/worker.h
index 55def23af..2823d4003 100644
--- a/daemon/worker.h
+++ b/daemon/worker.h
@@ -199,7 +199,7 @@ struct outbound_entry* worker_send_query(uint8_t* qname, size_t qnamelen,
 /** 
  * process control messages from the main thread. 
  * @param tube: tube control message came on.
- * @param buf: buffer with message in it.
+ * @param buffer: buffer with message in it.
  * @param error: if error (NETEVENT_*) happened.
  * @param arg: user argument
  */
diff --git a/libunbound/libworker.c b/libunbound/libworker.c
index 68f98e5e0..629eb3f6b 100644
--- a/libunbound/libworker.c
+++ b/libunbound/libworker.c
@@ -60,6 +60,7 @@
 #include "util/data/dname.h"
 #include "util/data/msgreply.h"
 #include "util/data/msgencode.h"
+#include "util/tube.h"
 
 /** handle new query command for bg worker */
 static void handle_newq(struct libworker* w, uint8_t* buf, uint32_t len);
@@ -963,12 +964,11 @@ libworker_read_msg(int fd, uint8_t** buf, uint32_t* len, int nonblock)
 }
 
 /* --- fake callbacks for fptr_wlist to work --- */
-int worker_handle_control_cmd(struct comm_point* ATTR_UNUSED(c), 
-	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
-        struct comm_reply* ATTR_UNUSED(reply_info))
+void worker_handle_control_cmd(struct tube* ATTR_UNUSED(tube), 
+	ldns_buffer* ATTR_UNUSED(buffer), int ATTR_UNUSED(error), 
+	void* ATTR_UNUSED(arg))
 {
 	log_assert(0);
-	return 0;
 }
 
 int worker_handle_request(struct comm_point* ATTR_UNUSED(c), 
diff --git a/smallapp/worker_cb.c b/smallapp/worker_cb.c
index 92e087e33..54d1f1fc8 100644
--- a/smallapp/worker_cb.c
+++ b/smallapp/worker_cb.c
@@ -45,13 +45,13 @@
 struct comm_reply;
 struct comm_point;
 struct module_qstate;
+struct tube;
 
-int worker_handle_control_cmd(struct comm_point* ATTR_UNUSED(c), 
-	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
-        struct comm_reply* ATTR_UNUSED(reply_info))
+void worker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
+	ldns_buffer* ATTR_UNUSED(buffer), int ATTR_UNUSED(error),
+	void* ATTR_UNUSED(arg))
 {
 	log_assert(0);
-	return 0;
 }
 
 int worker_handle_request(struct comm_point* ATTR_UNUSED(c), 
diff --git a/util/tube.h b/util/tube.h
index 00092ec91..fecd1cf33 100644
--- a/util/tube.h
+++ b/util/tube.h
@@ -50,8 +50,7 @@ struct tube;
  * void mycallback(tube, buffer, error, argument);
  * if error is true (NETEVENT_*), buffer is probably NULL.
  */
-typedef void (tube_callback_t)(struct tube* tube, ldns_buffer* buffer,
-	int error, void* arg);
+typedef void tube_callback_t(struct tube*, ldns_buffer*, int, void*);
 
 /**
  * A pipe