diff --git a/mt.c b/mt.c
index d4058c0..b53c8d8 100644
--- a/mt.c
+++ b/mt.c
@@ -22,6 +22,7 @@
 #include <sys/ioctl.h>
 #include <sys/stat.h>
 #include <sys/utsname.h>
+#include <sys/sysmacros.h>
 
 #include "mtio.h"