1 files changed, 4 insertions, 0 deletions

diff --git a/src/wsocket.h b/src/wsocket.h
index 0783b00..8fbc54d 100644
--- a/src/wsocket.h
+++ b/src/wsocket.h
@@ -16,6 +16,10 @@ typedef SOCKADDR_STORAGE t_sockaddr_storage;
 typedef SOCKET t_socket;
 typedef t_socket *p_socket;
 
+#ifndef IPV6_V6ONLY
+#define IPV6_V6ONLY 27
+#endif
+
 #define SOCKET_INVALID (INVALID_SOCKET)
 
 #ifndef SO_REUSEPORT