diff --git a/stepmania/src/RageFileDriverTimeout.cpp b/stepmania/src/RageFileDriverTimeout.cpp
index 7972b1f6f5..f5d3291e56 100644
--- a/stepmania/src/RageFileDriverTimeout.cpp
+++ b/stepmania/src/RageFileDriverTimeout.cpp
@@ -45,6 +45,7 @@
 #include "RageUtil.h"
 #include "RageUtil_FileDB.h"
 #include "RageLog.h"
+#include <errno.h>
 
 enum ThreadRequest
 {