Index: kernel/generic/src/cap/cap.c
===================================================================
--- kernel/generic/src/cap/cap.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/cap/cap.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -259,5 +259,5 @@
  * @param[out] handle  New capability handle on success.
  *
- * @return Negative error code in case of error.
+ * @return An error code in case of error.
  */
 int cap_alloc(task_t *task, cap_handle_t *handle)
Index: kernel/generic/src/debug/symtab.c
===================================================================
--- kernel/generic/src/debug/symtab.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/debug/symtab.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -50,5 +50,5 @@
  * @param offset Place to store offset from the symbol address.
  *
- * @return Zero on success or negative error code, ENOENT if not found,
+ * @return Zero on success or an error code, ENOENT if not found,
  *         ENOTSUP if symbol table not available.
  *
Index: kernel/generic/src/ipc/ipc.c
===================================================================
--- kernel/generic/src/ipc/ipc.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/ipc/ipc.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -205,5 +205,5 @@
  * @param request Call structure with request.
  *
- * @return EOK on success or a negative error code.
+ * @return EOK on success or an error code.
  *
  */
Index: kernel/generic/src/ipc/ipcrsc.c
===================================================================
--- kernel/generic/src/ipc/ipcrsc.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/ipc/ipcrsc.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -168,5 +168,5 @@
  * @param[out] out_handle  New phone capability handle.
  *
- * @return  Negative error code if a new capability cannot be allocated.
+ * @return  An error code if a new capability cannot be allocated.
  */
 int phone_alloc(task_t *task, cap_handle_t *out_handle)
Index: kernel/generic/src/ipc/irq.c
===================================================================
--- kernel/generic/src/ipc/irq.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/ipc/irq.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -387,5 +387,5 @@
  * @param handle  IRQ capability handle.
  *
- * @return EOK on success or a negative error code.
+ * @return EOK on success or an error code.
  *
  */
Index: kernel/generic/src/ipc/sysipc.c
===================================================================
--- kernel/generic/src/ipc/sysipc.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/ipc/sysipc.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -155,5 +155,5 @@
  * @param olddata Saved data of the request.
  *
- * @return Return EOK on success or a negative error code.
+ * @return Return EOK on success or an error code.
  *
  */
@@ -359,5 +359,5 @@
  *
  * @return EOK on success.
- * @return Negative error code on error.
+ * @return An error code on error.
  *
  */
@@ -740,5 +740,5 @@
  *                 for explanation.
  *
- * @return Negative error code on error.
+ * @return An error code on error.
  */
 sysarg_t sys_ipc_wait_for_call(ipc_data_t *calldata, uint32_t usec,
Index: kernel/generic/src/proc/program.c
===================================================================
--- kernel/generic/src/proc/program.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/proc/program.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -66,5 +66,5 @@
  * @param prg        Buffer for storing program information.
  *
- * @return EOK on success or negative error code.
+ * @return EOK on success or an error code.
  *
  */
@@ -134,5 +134,5 @@
  *                        will be returned.
  *
- * @return EOK on success or negative error code.
+ * @return EOK on success or an error code.
  *
  */
@@ -171,5 +171,5 @@
  * @param name Name to set for the program's task.
  *
- * @return EOK on success or negative error code.
+ * @return EOK on success or an error code.
  *
  */
Index: kernel/generic/src/syscall/copy.c
===================================================================
--- kernel/generic/src/syscall/copy.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/syscall/copy.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -57,5 +57,5 @@
  * @param size Size of the data to be copied.
  *
- * @return EOK on success or error code from @ref errno.h.
+ * @return EOK on success or an error code from @ref errno.h.
  */
 int copy_from_uspace(void *dst, const void *uspace_src, size_t size)
@@ -108,5 +108,5 @@
  * @param size Size of the data to be copied.
  *
- * @return 0 on success or error code from @ref errno.h.
+ * @return 0 on success or an error code from @ref errno.h.
  */
 int copy_to_uspace(void *uspace_dst, const void *src, size_t size)
Index: kernel/generic/src/udebug/udebug.c
===================================================================
--- kernel/generic/src/udebug/udebug.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/udebug/udebug.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -394,5 +394,5 @@
  * @param task Task structure. task->udebug.lock must be already locked.
  *
- * @return Zero on success or negative error code.
+ * @return Zero on success or an error code.
  *
  */
Index: kernel/generic/src/udebug/udebug_ops.c
===================================================================
--- kernel/generic/src/udebug/udebug_ops.c	(revision ee6f4342058a8205c52ba1e31e063a17c0cf6f18)
+++ kernel/generic/src/udebug/udebug_ops.c	(revision 13dc048ab1b8dfe020d96582cf64de71305f3834)
@@ -216,5 +216,5 @@
  * Closes the debugging session for the current task.
  *
- * @return Zero on success or negative error code.
+ * @return Zero on success or an error code.
  *
  */
@@ -236,5 +236,5 @@
  * @param mask Or combination of events that should be enabled.
  *
- * @return Zero on success or negative error code.
+ * @return Zero on success or an error code.
  *
  */