diff --git a/TOOLS/netstream.c b/TOOLS/netstream.c
index 8bc09b9a9d..300b1d3f80 100644
--- a/TOOLS/netstream.c
+++ b/TOOLS/netstream.c
@@ -28,7 +28,7 @@
 
 #include "config.h"
 
-#ifndef HAVE_WINSOCK2_H
+#if !HAVE_WINSOCK2_H
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>