diff --git a/libc/include/errno.h b/libc/include/errno.h
index a2408110db..2dcc3e5789 100644
--- a/libc/include/errno.h
+++ b/libc/include/errno.h
@@ -91,6 +91,8 @@ __BEGIN_DECLS
 #define ENOTBLK			82
 #define EEXISTS			83
 
+#define EUNKNOWN		0xFF
+
 #define errno __errno
 
 extern int __errno;
diff --git a/libc/include/sys/banan-os.h b/libc/include/sys/banan-os.h
index 9db8b93c45..cb2a41cf36 100644
--- a/libc/include/sys/banan-os.h
+++ b/libc/include/sys/banan-os.h
@@ -11,6 +11,9 @@ __BEGIN_DECLS
 #define TTY_FLAG_ENABLE_OUTPUT	1
 #define TTY_FLAG_ENABLE_INPUT	2
 
+#define POWER_SHUTDOWN 0
+#define POWER_REBOOT 1
+
 /*
 fildes:		refers to valid tty device
 command:	one of TTY_CMD_* definitions
diff --git a/libc/string.cpp b/libc/string.cpp
index f51d311084..3f4ba105ef 100644
--- a/libc/string.cpp
+++ b/libc/string.cpp
@@ -173,6 +173,7 @@ const char* strerrorname_np(int error)
 		case EXDEV:				return "EXDEV";
 		case EEXISTS:			return "EEXISTS";
 		case ENOTBLK:			return "ENOTBLK";
+		case EUNKNOWN:			return "EUNKNOWN";
 	}
 
 	errno = EINVAL;
@@ -267,6 +268,7 @@ const char* strerrordesc_np(int error)
 		case EXDEV:				return "Cross-device link.";
 		case EEXISTS:			return "File exists";
 		case ENOTBLK:			return "Block device required";
+		case EUNKNOWN:			return "Unknown error";
 	}
 
 	errno = EINVAL;