diff --git a/include/sys/shm.h b/include/sys/shm.h
index ce3029f5..bca6ed62 100644
--- a/include/sys/shm.h
+++ b/include/sys/shm.h
@@ -16,6 +16,9 @@ extern "C" {
 #include <sys/ipc.h>
 #include <bits/shm.h>
 
+#define SHM_R 0400
+#define SHM_W 0200
+
 #define SHM_RDONLY 010000
 #define SHM_RND    020000
 #define SHM_REMAP  040000