diff --git a/src/axl_io.c b/src/axl_io.c
index df1016a..ad8cdad 100644
--- a/src/axl_io.c
+++ b/src/axl_io.c
@@ -6,6 +6,7 @@
 
 /* file open modes */
 #include <sys/file.h>
+#include <fcntl.h>
 
 /* exit & malloc */
 #include <stdlib.h>