diff --git a/driver-ti.c b/driver-ti.c
index 11b8ef2..7424c4e 100644
--- a/driver-ti.c
+++ b/driver-ti.c
@@ -1,4 +1,5 @@
 // we want strdup()
+#define _XPG6
 #define _XOPEN_SOURCE 500
 
 #include "termkey.h"