diff --git a/rsync.h b/rsync.h
index cf48611d..a4b993e1 100644
--- a/rsync.h
+++ b/rsync.h
@@ -284,6 +284,7 @@ enum msgcode {
 
 #include <stdarg.h>
 #include <netinet/in.h>
+#include <netinet/ip.h>
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <syslog.h>