From 4b35a635629f852eccbbfc68d454083586804072 Mon Sep 17 00:00:00 2001
From: Juhani Haverinen <juhani.haverinen@gmail.com>
Date: Tue, 12 Jul 2016 17:16:21 +0300
Subject: [PATCH] Only attempt to set IPV6_V6ONLY for IPv6 sockets

---
 neomi.py | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/neomi.py b/neomi.py
index 90c05b2..ec93ac2 100644
--- a/neomi.py
+++ b/neomi.py
@@ -36,10 +36,12 @@ def bind(port, backlog = 1):
 			s = socket.socket(af, socktype, proto)
 		except OSError:
 			continue
-		try:
-			s.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
-		except OSError:
-			pass
+		# Make IPv6 socket only bind on IPv6 address, otherwise may clash with IPv4 and not get enabled
+		if af == socket.AF_INET6:
+			try:
+				s.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
+			except OSError:
+				pass
 		try:
 			s.bind(sa)
 			s.listen(backlog)