diff --git a/src/libstrongswan/utils/utils.h b/src/libstrongswan/utils/utils.h
index ced47a4b8..5a455baff 100644
--- a/src/libstrongswan/utils/utils.h
+++ b/src/libstrongswan/utils/utils.h
@@ -83,6 +83,15 @@
 #include "enum.h"
 #include "utils/strerror.h"
 
+/**
+ * Directory separator character in paths on this platform
+ */
+#ifdef WIN32
+# define DIRECTORY_SEPARATOR "\\"
+#else
+# define DIRECTORY_SEPARATOR "/"
+#endif
+
 /**
  * Initialize utility functions
  */