Index: uspace/lib/hound/include/hound/client.h
===================================================================
--- uspace/lib/hound/include/hound/client.h	(revision fed5a9b5f65e62d1606031ba5f462ca39ca10bcf)
+++ uspace/lib/hound/include/hound/client.h	(revision 3b47db687606b55f2694aaa5c4c6db563b5b61eb)
@@ -53,14 +53,14 @@
 void hound_context_destroy(hound_context_t *hound);
 
-int hound_context_set_main_stream_params(hound_context_t *hound,
+errno_t hound_context_set_main_stream_params(hound_context_t *hound,
     pcm_format_t format, size_t bsize);
 
-int hound_context_get_available_targets(hound_context_t *hound,
+errno_t hound_context_get_available_targets(hound_context_t *hound,
     const char ***names, size_t *count);
-int hound_context_get_connected_targets(hound_context_t *hound,
+errno_t hound_context_get_connected_targets(hound_context_t *hound,
     const char ***names, size_t *count);
 
-int hound_context_connect_target(hound_context_t *hound, const char* target);
-int hound_context_disconnect_target(hound_context_t *hound, const char* target);
+errno_t hound_context_connect_target(hound_context_t *hound, const char* target);
+errno_t hound_context_disconnect_target(hound_context_t *hound, const char* target);
 
 hound_stream_t *hound_stream_create(hound_context_t *hound, unsigned flags,
@@ -68,14 +68,14 @@
 void hound_stream_destroy(hound_stream_t *stream);
 
-int hound_stream_write(hound_stream_t *stream, const void *data, size_t size);
-int hound_stream_read(hound_stream_t *stream, void *data, size_t size);
-int hound_stream_drain(hound_stream_t *stream);
+errno_t hound_stream_write(hound_stream_t *stream, const void *data, size_t size);
+errno_t hound_stream_read(hound_stream_t *stream, void *data, size_t size);
+errno_t hound_stream_drain(hound_stream_t *stream);
 
-int hound_write_main_stream(hound_context_t *hound,
+errno_t hound_write_main_stream(hound_context_t *hound,
     const void *data, size_t size);
-int hound_read_main_stream(hound_context_t *hound, void *data, size_t size);
-int hound_write_replace_main_stream(hound_context_t *hound,
+errno_t hound_read_main_stream(hound_context_t *hound, void *data, size_t size);
+errno_t hound_write_replace_main_stream(hound_context_t *hound,
     const void *data, size_t size);
-int hound_write_immediate(hound_context_t *hound,
+errno_t hound_write_immediate(hound_context_t *hound,
     pcm_format_t format, const void *data, size_t size);
 
Index: uspace/lib/hound/include/hound/protocol.h
===================================================================
--- uspace/lib/hound/include/hound/protocol.h	(revision fed5a9b5f65e62d1606031ba5f462ca39ca10bcf)
+++ uspace/lib/hound/include/hound/protocol.h	(revision 3b47db687606b55f2694aaa5c4c6db563b5b61eb)
@@ -61,9 +61,9 @@
 void hound_service_disconnect(hound_sess_t *sess);
 
-int hound_service_register_context(hound_sess_t *sess,
+errno_t hound_service_register_context(hound_sess_t *sess,
     const char *name, bool record, hound_context_id_t *id);
-int hound_service_unregister_context(hound_sess_t *sess, hound_context_id_t id);
+errno_t hound_service_unregister_context(hound_sess_t *sess, hound_context_id_t id);
 
-int hound_service_get_list(hound_sess_t *sess, const char ***ids, size_t *count,
+errno_t hound_service_get_list(hound_sess_t *sess, const char ***ids, size_t *count,
     int flags, const char *connection);
 
@@ -76,5 +76,5 @@
  * @return Error code.
  */
-static inline int hound_service_get_list_all(hound_sess_t *sess,
+static inline errno_t hound_service_get_list_all(hound_sess_t *sess,
     const char ***ids, size_t *count, int flags)
 {
@@ -82,16 +82,16 @@
 }
 
-int hound_service_connect_source_sink(hound_sess_t *sess, const char *source,
+errno_t hound_service_connect_source_sink(hound_sess_t *sess, const char *source,
     const char *sink);
-int hound_service_disconnect_source_sink(hound_sess_t *sess, const char *source,
+errno_t hound_service_disconnect_source_sink(hound_sess_t *sess, const char *source,
     const char *sink);
 
-int hound_service_stream_enter(async_exch_t *exch, hound_context_id_t id,
+errno_t hound_service_stream_enter(async_exch_t *exch, hound_context_id_t id,
     int flags, pcm_format_t format, size_t bsize);
-int hound_service_stream_drain(async_exch_t *exch);
-int hound_service_stream_exit(async_exch_t *exch);
+errno_t hound_service_stream_drain(async_exch_t *exch);
+errno_t hound_service_stream_exit(async_exch_t *exch);
 
-int hound_service_stream_write(async_exch_t *exch, const void *data, size_t size);
-int hound_service_stream_read(async_exch_t *exch, void *data, size_t size);
+errno_t hound_service_stream_write(async_exch_t *exch, const void *data, size_t size);
+errno_t hound_service_stream_read(async_exch_t *exch, void *data, size_t size);
 
 /* Server */
@@ -100,26 +100,26 @@
 typedef struct hound_server_iface {
 	/** Create new context */
-	int (*add_context)(void *, hound_context_id_t *, const char *, bool);
+	errno_t (*add_context)(void *, hound_context_id_t *, const char *, bool);
 	/** Destroy existing context */
-	int (*rem_context)(void *, hound_context_id_t);
+	errno_t (*rem_context)(void *, hound_context_id_t);
 	/** Query context direction */
 	bool (*is_record_context)(void *, hound_context_id_t);
 	/** Get string identifiers of specified objects */
-	int (*get_list)(void *, const char ***, size_t *, const char *, int);
+	errno_t (*get_list)(void *, const char ***, size_t *, const char *, int);
 	/** Create connection between source and sink */
-	int (*connect)(void *, const char *, const char *);
+	errno_t (*connect)(void *, const char *, const char *);
 	/** Destroy connection between source and sink */
-	int (*disconnect)(void *, const char *, const char *);
+	errno_t (*disconnect)(void *, const char *, const char *);
 	/** Create new stream tied to the context */
-	int (*add_stream)(void *, hound_context_id_t, int, pcm_format_t, size_t,
+	errno_t (*add_stream)(void *, hound_context_id_t, int, pcm_format_t, size_t,
 	    void **);
 	/** Destroy existing stream */
-	int (*rem_stream)(void *, void *);
+	errno_t (*rem_stream)(void *, void *);
 	/** Block until the stream buffer is empty */
-	int (*drain_stream)(void *);
+	errno_t (*drain_stream)(void *);
 	/** Write new data to the stream */
-	int (*stream_data_write)(void *, const void *, size_t);
+	errno_t (*stream_data_write)(void *, const void *, size_t);
 	/** Read data from the stream */
-	int (*stream_data_read)(void *, void *, size_t);
+	errno_t (*stream_data_read)(void *, void *, size_t);
 	void *server;
 } hound_server_iface_t;
Index: uspace/lib/hound/include/hound/server.h
===================================================================
--- uspace/lib/hound/include/hound/server.h	(revision fed5a9b5f65e62d1606031ba5f462ca39ca10bcf)
+++ uspace/lib/hound/include/hound/server.h	(revision 3b47db687606b55f2694aaa5c4c6db563b5b61eb)
@@ -41,10 +41,10 @@
 
 typedef void (*dev_change_callback_t)(void);
-typedef int (*device_callback_t)(service_id_t, const char *);
+typedef errno_t (*device_callback_t)(service_id_t, const char *);
 
-int hound_server_register(const char *name, service_id_t *id);
+errno_t hound_server_register(const char *name, service_id_t *id);
 void hound_server_unregister(service_id_t id);
-int hound_server_set_device_change_callback(dev_change_callback_t cb);
-int hound_server_devices_iterate(device_callback_t callback);
+errno_t hound_server_set_device_change_callback(dev_change_callback_t cb);
+errno_t hound_server_devices_iterate(device_callback_t callback);
 
 #endif