Index: uspace/lib/c/include/device/char.h
===================================================================
--- uspace/lib/c/include/device/char.h	(revision c47e1a8fb8e2a2556518fd57f186595422ca4484)
+++ uspace/lib/c/include/device/char.h	(revision a6ba0c9cb46c31fab5fccc5ab7ff90a3a8cacb82)
@@ -26,5 +26,5 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
- 
+
  /** @addtogroup libc
  * @{
@@ -32,5 +32,5 @@
 /** @file
  */
- 
+
 #ifndef LIBC_DEVICE_HW_RES_H_
 #define LIBC_DEVICE_HW_RES_H_
@@ -38,9 +38,9 @@
 typedef enum {
 	CHAR_READ_DEV = 0,
-	CHAR_WRITE_DEV	
+	CHAR_WRITE_DEV
 } hw_res_funcs_t;
 
-int read_dev(int dev_phone, void *buf, size_t len);
-int write_dev(int dev_phone, void *buf, size_t len);
+ssize_t read_dev(int dev_phone, void *buf, size_t len);
+ssize_t write_dev(int dev_phone, void *buf, size_t len);
 
 #endif