Index: uspace/dist/src/c/demos/tetris/scores.c
===================================================================
--- uspace/dist/src/c/demos/tetris/scores.c	(revision cf13b1787530fe212a0ac74399fd6d4b0f096731)
+++ uspace/dist/src/c/demos/tetris/scores.c	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -206,9 +206,9 @@
 }
 
-int loadscores(void)
+errno_t loadscores(void)
 {
 	FILE *f;
 	size_t cnt;
-	int rc;
+	errno_t rc;
 
 	f = fopen("/data/tetris.sco", "rb");
@@ -229,5 +229,5 @@
 	FILE *f;
 	size_t cnt;
-	int rc;
+	errno_t rc;
 
 	f = fopen("/data/tetris.sco", "wb");
Index: uspace/dist/src/c/demos/tetris/scores.h
===================================================================
--- uspace/dist/src/c/demos/tetris/scores.h	(revision cf13b1787530fe212a0ac74399fd6d4b0f096731)
+++ uspace/dist/src/c/demos/tetris/scores.h	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -72,5 +72,5 @@
 extern void initscores(void);
 extern void insertscore(int score, int level);
-extern int loadscores(void);
+extern errno_t loadscores(void);
 extern void savescores(void);
 
Index: uspace/dist/src/c/demos/tetris/screen.c
===================================================================
--- uspace/dist/src/c/demos/tetris/screen.c	(revision cf13b1787530fe212a0ac74399fd6d4b0f096731)
+++ uspace/dist/src/c/demos/tetris/screen.c	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -147,5 +147,5 @@
 {
 	sysarg_t ccap;
-	int rc = console_get_color_cap(console, &ccap);
+	errno_t rc = console_get_color_cap(console, &ccap);
 	
 	if (rc != 0)
@@ -353,5 +353,5 @@
  *
  */
-int tgetchar(void)
+errno_t tgetchar(void)
 {
 	/*
@@ -392,5 +392,5 @@
  *
  */
-int twait(void)
+errno_t twait(void)
 {
 	wchar_t c = 0;
Index: uspace/dist/src/c/demos/tetris/screen.h
===================================================================
--- uspace/dist/src/c/demos/tetris/screen.h	(revision cf13b1787530fe212a0ac74399fd6d4b0f096731)
+++ uspace/dist/src/c/demos/tetris/screen.h	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -71,5 +71,5 @@
 extern void clear_screen(void);
 
-extern int put(int);
+extern errno_t put(int);
 extern void scr_clear(void);
 extern void scr_end(void);
@@ -80,6 +80,6 @@
 
 extern void tsleep(void);
-extern int tgetchar(void);
-extern int twait(void);
+extern errno_t tgetchar(void);
+extern errno_t twait(void);
 
 /** @}
Index: uspace/dist/src/c/demos/tetris/shapes.c
===================================================================
--- uspace/dist/src/c/demos/tetris/shapes.c	(revision cf13b1787530fe212a0ac74399fd6d4b0f096731)
+++ uspace/dist/src/c/demos/tetris/shapes.c	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -93,5 +93,5 @@
  * taking the current board into account.
  */
-int fits_in(const struct shape *shape, int pos)
+errno_t fits_in(const struct shape *shape, int pos)
 {
 	const int *o = shape->off;
Index: uspace/dist/src/c/demos/tetris/tetris.h
===================================================================
--- uspace/dist/src/c/demos/tetris/tetris.h	(revision cf13b1787530fe212a0ac74399fd6d4b0f096731)
+++ uspace/dist/src/c/demos/tetris/tetris.h	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -194,5 +194,5 @@
 extern int classic;
 
-extern int fits_in(const struct shape *, int);
+extern errno_t fits_in(const struct shape *, int);
 extern void place(const struct shape *, int, int);
 extern void stop(const char *);