diff --git a/libc/sysv/consts/pr.h b/libc/sysv/consts/pr.h
index fded62fdf..4006e3949 100644
--- a/libc/sysv/consts/pr.h
+++ b/libc/sysv/consts/pr.h
@@ -99,6 +99,8 @@
 #define PR_SET_SPECULATION_CTRL     53
 #define PR_SET_TAGGED_ADDR_CTRL     55
 #define PR_GET_TAGGED_ADDR_CTRL     56
+#define PR_SET_IO_FLUSHER           57
+#define PR_GET_IO_FLUSHER           58
 #define PR_SET_PTRACER              0x59616d61
 #define PR_SET_PTRACER_ANY          -1