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Socket v6only #18

merged 1 commit into from

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IPV6_V6ONLY is set to 0 in Network.Socket.socket.
This option must be set between socket() and bind().
If we set this in Network.Socket.bind, there is no choice for users to set it to 1.
Thus, this is set in Network.Socket.socket.

@tibbe tibbe merged commit 51b2c5a into from
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Commits on Sep 28, 2011
  1. @kazu-yamamoto
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Showing with 11 additions and 5 deletions.
  1. +4 −4 Network.hs
  2. +7 −1 Network/Socket.hsc
8 Network.hs
@@ -160,13 +160,16 @@ connect' host serv = do
-- | Creates the server side socket which has been bound to the
--- specified port.
+-- specified port.
-- NOTE: To avoid the \"Address already in use\"
-- problems popped up several times on the GHC-Users mailing list we
-- set the 'ReuseAddr' socket option on the listening socket. If you
-- don't want this behaviour, please use the lower level
-- 'Network.Socket.listen' instead.
+-- If available, the 'IPv6Only' socket option is set to 0
+-- so that both IPv4 and IPv6 can be accepted with this socket.
listenOn :: PortID -- ^ Port Identifier
-> IO Socket -- ^ Connected Socket
@@ -240,9 +243,6 @@ listen' serv = do
(\sock -> do
setSocketOption sock ReuseAddr 1
- setSocketOption sock IPv6Only 0
bindSocket sock (addrAddress addr)
listen sock maxListenQueue
return sock
8 Network/Socket.hsc
@@ -402,6 +402,8 @@ instance Show SockAddr where
-- and protocol number. The address family is usually 'AF_INET',
-- 'AF_INET6', or 'AF_UNIX'. The socket type is usually 'Stream' or
-- 'Datagram'. The protocol number is usually 'defaultProtocol'.
+-- If 'AF_INET6' is used, the 'IPv6Only' socket option is set to 0
+-- so that both IPv4 and IPv6 can be handled with one socket.
socket :: Family -- Family Name (usually AF_INET)
-> SocketType -- Socket Type (usually Stream)
-> ProtocolNumber -- Protocol Number (getProtocolByName to find value)
@@ -417,7 +419,11 @@ socket family stype protocol = do
# endif
socket_status <- newMVar NotConnected
- return (MkSocket fd family stype protocol socket_status)
+ let sock = MkSocket fd family stype protocol socket_status
+ when (family == AF_INET6) $ setSocketOption sock IPv6Only 0
+ return sock
-- | Build a pair of connected socket objects using the given address
-- family, socket type, and protocol number. Address family, socket
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