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--- a/src/internfile/mh_mbox.cpp
+++ b/src/internfile/mh_mbox.cpp
@@ -24,8 +24,9 @@
 #include <unistd.h>
 #include <time.h>
 #include <regex.h>
+#include <sys/stat.h>
+
 #include <cstring>
-
 #include <map>
 #include <sstream>
 #include <fstream>