diff --git a/pattern.h b/pattern.h
index 51ff298..65af64e 100644
--- a/pattern.h
+++ b/pattern.h
@@ -28,6 +28,7 @@
 #include "winglue.h"
 #else
 #define INLINE inline
+#define PRSIZET "z"
 #include <sys/time.h>
 #include <sys/stat.h>
 #include <errno.h>
diff --git a/winglue.h b/winglue.h
index d499733..896a4b7 100644
--- a/winglue.h
+++ b/winglue.h
@@ -41,4 +41,6 @@ extern int getopt(int argc, TCHAR *argv[], TCHAR *optstring);
 
 extern int count_processors(void);
 
+#define PRSIZET "I"
+
 #endif /* !defined (__VG_WINGLUE_H__) */