diff --git a/newlib/libc/sys/rtems/include/sys/un.h b/newlib/libc/sys/rtems/include/sys/un.h
index 3a011aeef..e02484151 100644
--- a/newlib/libc/sys/rtems/include/sys/un.h
+++ b/newlib/libc/sys/rtems/include/sys/un.h
@@ -67,6 +67,7 @@ struct sockaddr_un {
 /* Socket options. */
 #define	LOCAL_PEERCRED		1	/* retrieve peer credentials */
 #define	LOCAL_CREDS		2	/* pass credentials to receiver */
+#define	LOCAL_CREDS_PERSISTENT	3	/* pass credentials to receiver */
 #define	LOCAL_CONNWAIT		4	/* connects block until accepted */
 
 /* Start of reserved space for third-party socket options. */