diff --git a/libc/include/fcntl.h b/libc/include/fcntl.h
index db56ce3..f57c320 100644
--- a/libc/include/fcntl.h
+++ b/libc/include/fcntl.h
@@ -46,6 +46,7 @@
 #endif
 
 #define O_ASYNC FASYNC
+#define O_RSYNC O_SYNC
 
 #define SPLICE_F_MOVE 1
 #define SPLICE_F_NONBLOCK 2