diff --git a/source/fs/sd_fat_devoptab.cpp b/source/fs/sd_fat_devoptab.cpp
index 6f51511..70c596b 100644
--- a/source/fs/sd_fat_devoptab.cpp
+++ b/source/fs/sd_fat_devoptab.cpp
@@ -30,6 +30,7 @@
 #include <stdio.h>
 #include <dynamic_libs/fs_functions.h>
 #include <dynamic_libs/os_functions.h>
+#include <sys/iosupport.h>
 
 #include "disc_io.h"
 #include "FSOSUtils.h"