diff --git a/Libraries/LibC/mman.h b/Libraries/LibC/mman.h
index 86c020c11c..5147914129 100644
--- a/Libraries/LibC/mman.h
+++ b/Libraries/LibC/mman.h
@@ -3,6 +3,7 @@
 #include <sys/cdefs.h>
 #include <sys/types.h>
 
+#define MAP_FILE 0x00
 #define MAP_SHARED 0x01
 #define MAP_PRIVATE 0x02
 #define MAP_FIXED 0x10