diff --git a/include/rtdef.h b/include/rtdef.h
index 1966595ced27..3fdc381ab3b3 100644
--- a/include/rtdef.h
+++ b/include/rtdef.h
@@ -60,6 +60,7 @@
 #include <stddef.h>
 #include <stdarg.h>
 #include <sys/types.h>
+#include <sys/errno.h>
 #endif /* RT_USING_LIBC */
 
 #ifdef __cplusplus
@@ -380,12 +381,30 @@ typedef int (*init_fn_t)(void);
 #endif
 
 /**
- * @addtogroup Error
+ * @addtogroup Error Code
  */
 
 /**@{*/
 
 /* RT-Thread error code definitions */
+#ifdef RT_USING_LIBC
+/* POSIX error code compatible */
+#define RT_EOK                          0               /**< There is no error */
+#define RT_ERROR                        ERROR           /**< A generic error happens */
+#define RT_ETIMEOUT                     ETIMEDOUT       /**< Timed out */
+#define RT_EFULL                        ETIMEDOUT       /**< The resource is full */
+#define RT_EEMPTY                       ENODATA         /**< The resource is empty */
+#define RT_ENOMEM                       ENOMEM          /**< No memory */
+#define RT_ENOSYS                       ENOSYS          /**< No system */
+#define RT_EBUSY                        EBUSY           /**< Busy */
+#define RT_EIO                          EIO             /**< IO error */
+#define RT_EINTR                        EINTR           /**< Interrupted system call */
+#define RT_EINVAL                       EINVAL          /**< Invalid argument */
+#define RT_ETRAP                        ETRAP           /**< Trap event */
+#define RT_ENOENT                       ENOENT          /**< No entry */
+#define RT_ENOSPC                       ENOSPC          /**< No space left */
+#define RT_EPERM                        EPERM           /**< Operation not permitted */
+#else
 #define RT_EOK                          0               /**< There is no error */
 #define RT_ERROR                        1               /**< A generic error happens */
 #define RT_ETIMEOUT                     2               /**< Timed out */
@@ -401,6 +420,7 @@ typedef int (*init_fn_t)(void);
 #define RT_ENOENT                       12              /**< No entry */
 #define RT_ENOSPC                       13              /**< No space left */
 #define RT_EPERM                        14              /**< Operation not permitted */
+#endif /* RT_USING_LIBC */
 
 /**@}*/