diff --git a/uloop.c b/uloop.c
index e361c37..f226f50 100644
--- a/uloop.c
+++ b/uloop.c
@@ -39,6 +39,7 @@
 #ifdef USE_EPOLL
 #include <sys/epoll.h>
 #endif
+#include <sys/wait.h>
 
 
 #ifndef ARRAY_SIZE