diff --git a/include/sys/random.h b/include/sys/random.h
index 401146b4ee3..4ac586176b9 100644
--- a/include/sys/random.h
+++ b/include/sys/random.h
@@ -44,6 +44,22 @@
 #include <nuttx/config.h>
 #include <stddef.h>
 
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/*
+ * Flags for getrandom(2)
+ *
+ * GRND_NONBLOCK  Don't block and return EAGAIN instead
+ * GRND_RANDOM    No effect
+ * GRND_INSECURE  Return non-cryptographic random bytes
+ */
+
+#define GRND_NONBLOCK   0x0001
+#define GRND_RANDOM     0x0002
+#define GRND_INSECURE   0x0004
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/