diff --git a/lib-src/wakeup.c b/lib-src/wakeup.c
index d2035e3a523..07c324d1210 100644
--- a/lib-src/wakeup.c
+++ b/lib-src/wakeup.c
@@ -2,6 +2,7 @@
 
 #include <stdio.h>
 #include <time.h>
+#include <sys/types.h>
 #include <sys/time.h>
 
 struct tm *localtime ();