Imported Upstream version 2011.08.17

26 files changed, 2652 insertions, 1465 deletions

diff --git a/src/pkg/net/Makefile b/src/pkg/net/Makefile
index 6b3d0b328..eba9e26d9 100644
--- a/src/pkg/net/Makefile
+++ b/src/pkg/net/Makefile
@@ -9,16 +9,14 @@ GOFILES=\
 	dial.go\
 	dnsclient.go\
 	dnsmsg.go\
-	fd_$(GOOS).go\
 	hosts.go\
 	interface.go\
 	ip.go\
-	ipsock.go\
 	iprawsock.go\
+	ipsock.go\
 	net.go\
 	parse.go\
 	pipe.go\
-	sock.go\
 	tcpsock.go\
 	udpsock.go\
 	unixsock.go\
@@ -27,80 +25,129 @@ GOFILES_freebsd=\
 	dnsclient_unix.go\
 	dnsconfig.go\
 	fd.go\
+	fd_$(GOOS).go\
 	file.go\
 	interface_bsd.go\
 	interface_freebsd.go\
+	iprawsock_posix.go\
+	ipsock_posix.go\
 	lookup_unix.go\
 	newpollserver.go\
 	port.go\
 	sendfile_stub.go\
+	sock.go\
 	sock_bsd.go\
+	tcpsock_posix.go\
+	udpsock_posix.go\
+	unixsock_posix.go\
 
+ifeq ($(CGO_ENABLED),1)
 CGOFILES_freebsd=\
 	cgo_bsd.go\
-	cgo_unix.go\
+	cgo_unix.go
+else
+GOFILES_freebsd+=cgo_stub.go
+endif
 
 GOFILES_darwin=\
 	dnsclient_unix.go\
 	dnsconfig.go\
 	fd.go\
+	fd_$(GOOS).go\
 	file.go\
 	interface_bsd.go\
 	interface_darwin.go\
+	iprawsock_posix.go\
+	ipsock_posix.go\
 	lookup_unix.go\
 	newpollserver.go\
 	port.go\
 	sendfile_stub.go\
+	sock.go\
 	sock_bsd.go\
+	tcpsock_posix.go\
+	udpsock_posix.go\
+	unixsock_posix.go\
 
+ifeq ($(CGO_ENABLED),1)
 CGOFILES_darwin=\
 	cgo_bsd.go\
-	cgo_unix.go\
+	cgo_unix.go
+else
+GOFILES_darwin+=cgo_stub.go
+endif
 
 GOFILES_linux=\
 	dnsclient_unix.go\
 	dnsconfig.go\
 	fd.go\
+	fd_$(GOOS).go\
 	file.go\
 	interface_linux.go\
+	iprawsock_posix.go\
+	ipsock_posix.go\
 	lookup_unix.go\
 	newpollserver.go\
 	port.go\
 	sendfile_linux.go\
+	sock.go\
 	sock_linux.go\
+	tcpsock_posix.go\
+	udpsock_posix.go\
+	unixsock_posix.go\
+
+ifeq ($(CGO_ENABLED),1)
+CGOFILES_linux=\
+	cgo_linux.go\
+	cgo_unix.go
+else
+GOFILES_linux+=cgo_stub.go
+endif
 
 GOFILES_openbsd=\
-	dnsclient.go\
+	dnsclient_unix.go\
 	dnsconfig.go\
 	fd.go\
+	fd_$(GOOS).go\
 	file.go\
 	interface_bsd.go\
+	interface_openbsd.go\
+	iprawsock_posix.go\
+	ipsock_posix.go\
+	lookup_unix.go\
 	newpollserver.go\
 	port.go\
 	sendfile_stub.go\
+	sock.go\
 	sock_bsd.go\
+	tcpsock_posix.go\
+	udpsock_posix.go\
+	unixsock_posix.go\
 	cgo_stub.go\
 
 GOFILES_plan9=\
+	file_plan9.go\
 	interface_stub.go\
-	lookup_unix.go\
-	sendfile_stub.go\
-
-ifeq ($(GOARCH),arm)
-# ARM has no cgo, so use the stubs.
-GOFILES_linux+=cgo_stub.go
-else
-CGOFILES_linux=\
-	cgo_linux.go\
-	cgo_unix.go
-endif
+	iprawsock_plan9.go\
+	ipsock_plan9.go\
+	lookup_plan9.go\
+	tcpsock_plan9.go\
+	udpsock_plan9.go\
+	unixsock_plan9.go\
 
 GOFILES_windows=\
+	fd_$(GOOS).go\
 	file_windows.go\
 	interface_windows.go\
+	iprawsock_posix.go\
+	ipsock_posix.go\
 	lookup_windows.go\
 	sendfile_windows.go\
+	sock.go\
 	sock_windows.go\
+	tcpsock_posix.go\
+	udpsock_posix.go\
+	unixsock_posix.go\
 
 GOFILES+=$(GOFILES_$(GOOS))
 ifneq ($(CGOFILES_$(GOOS)),)
diff --git a/src/pkg/net/fd.go b/src/pkg/net/fd.go
index cd1a21dc3..707dccaa4 100644
--- a/src/pkg/net/fd.go
+++ b/src/pkg/net/fd.go
@@ -585,20 +585,25 @@ func (fd *netFD) accept(toAddr func(syscall.Sockaddr) Addr) (nfd *netFD, err os.
 
 	fd.incref()
 	defer fd.decref()
+	if fd.rdeadline_delta > 0 {
+		fd.rdeadline = pollserver.Now() + fd.rdeadline_delta
+	} else {
+		fd.rdeadline = 0
+	}
 
 	// See ../syscall/exec.go for description of ForkLock.
 	// It is okay to hold the lock across syscall.Accept
 	// because we have put fd.sysfd into non-blocking mode.
 	syscall.ForkLock.RLock()
 	var s, e int
-	var sa syscall.Sockaddr
+	var rsa syscall.Sockaddr
 	for {
 		if fd.closing {
 			syscall.ForkLock.RUnlock()
 			return nil, os.EINVAL
 		}
-		s, sa, e = syscall.Accept(fd.sysfd)
-		if e != syscall.EAGAIN {
+		s, rsa, e = syscall.Accept(fd.sysfd)
+		if e != syscall.EAGAIN || fd.rdeadline < 0 {
 			break
 		}
 		syscall.ForkLock.RUnlock()
@@ -616,7 +621,8 @@ func (fd *netFD) accept(toAddr func(syscall.Sockaddr) Addr) (nfd *netFD, err os.
 		syscall.Close(s)
 		return nil, err
 	}
-	nfd.setAddr(fd.laddr, toAddr(sa))
+	lsa, _ := syscall.Getsockname(nfd.sysfd)
+	nfd.setAddr(toAddr(lsa), toAddr(rsa))
 	return nfd, nil
 }
 
diff --git a/src/pkg/net/file_plan9.go b/src/pkg/net/file_plan9.go
new file mode 100644
index 000000000..a07e74331
--- /dev/null
+++ b/src/pkg/net/file_plan9.go
@@ -0,0 +1,33 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"os"
+)
+
+// FileConn returns a copy of the network connection corresponding to
+// the open file f.  It is the caller's responsibility to close f when
+// finished.  Closing c does not affect f, and closing f does not
+// affect c.
+func FileConn(f *os.File) (c Conn, err os.Error) {
+	return nil, os.EPLAN9
+}
+
+// FileListener returns a copy of the network listener corresponding
+// to the open file f.  It is the caller's responsibility to close l
+// when finished.  Closing c does not affect l, and closing l does not
+// affect c.
+func FileListener(f *os.File) (l Listener, err os.Error) {
+	return nil, os.EPLAN9
+}
+
+// FilePacketConn returns a copy of the packet network connection
+// corresponding to the open file f.  It is the caller's
+// responsibility to close f when finished.  Closing c does not affect
+// f, and closing f does not affect c.
+func FilePacketConn(f *os.File) (c PacketConn, err os.Error) {
+	return nil, os.EPLAN9
+}
diff --git a/src/pkg/net/file_test.go b/src/pkg/net/file_test.go
index bd1e2c9d7..9a8c2dcbc 100644
--- a/src/pkg/net/file_test.go
+++ b/src/pkg/net/file_test.go
@@ -57,7 +57,7 @@ func testFileListener(t *testing.T, net, laddr string) {
 }
 
 func TestFileListener(t *testing.T) {
-	if runtime.GOOS == "windows" {
+	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
 		return
 	}
 	testFileListener(t, "tcp", "127.0.0.1")
@@ -116,7 +116,7 @@ func testFilePacketConnDial(t *testing.T, net, raddr string) {
 }
 
 func TestFilePacketConn(t *testing.T) {
-	if runtime.GOOS == "windows" {
+	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
 		return
 	}
 	testFilePacketConnListen(t, "udp", "127.0.0.1:0")
diff --git a/src/pkg/net/interface_bsd.go b/src/pkg/net/interface_bsd.go
index 130820d4a..2675f94b9 100644
--- a/src/pkg/net/interface_bsd.go
+++ b/src/pkg/net/interface_bsd.go
@@ -169,34 +169,3 @@ func newAddr(m *syscall.InterfaceAddrMessage) ([]Addr, os.Error) {
 
 	return ifat, nil
 }
-
-func newMulticastAddr(m *syscall.InterfaceMulticastAddrMessage) ([]Addr, os.Error) {
-	var ifmat []Addr
-
-	sas, e := syscall.ParseRoutingSockaddr(m)
-	if e != 0 {
-		return nil, os.NewSyscallError("route sockaddr", e)
-	}
-
-	for _, s := range sas {
-		switch v := s.(type) {
-		case *syscall.SockaddrInet4:
-			ifma := &IPAddr{IP: IPv4(v.Addr[0], v.Addr[1], v.Addr[2], v.Addr[3])}
-			ifmat = append(ifmat, ifma.toAddr())
-		case *syscall.SockaddrInet6:
-			ifma := &IPAddr{IP: make(IP, IPv6len)}
-			copy(ifma.IP, v.Addr[:])
-			// NOTE: KAME based IPv6 protcol stack usually embeds
-			// the interface index in the interface-local or link-
-			// local address as the kernel-internal form.
-			if ifma.IP.IsInterfaceLocalMulticast() ||
-				ifma.IP.IsLinkLocalMulticast() {
-				// remove embedded scope zone ID
-				ifma.IP[2], ifma.IP[3] = 0, 0
-			}
-			ifmat = append(ifmat, ifma.toAddr())
-		}
-	}
-
-	return ifmat, nil
-}
diff --git a/src/pkg/net/interface_darwin.go b/src/pkg/net/interface_darwin.go
index 6fbcd3723..a7b68ad7f 100644
--- a/src/pkg/net/interface_darwin.go
+++ b/src/pkg/net/interface_darwin.go
@@ -47,3 +47,34 @@ func interfaceMulticastAddrTable(ifindex int) ([]Addr, os.Error) {
 
 	return ifmat, nil
 }
+
+func newMulticastAddr(m *syscall.InterfaceMulticastAddrMessage) ([]Addr, os.Error) {
+	var ifmat []Addr
+
+	sas, e := syscall.ParseRoutingSockaddr(m)
+	if e != 0 {
+		return nil, os.NewSyscallError("route sockaddr", e)
+	}
+
+	for _, s := range sas {
+		switch v := s.(type) {
+		case *syscall.SockaddrInet4:
+			ifma := &IPAddr{IP: IPv4(v.Addr[0], v.Addr[1], v.Addr[2], v.Addr[3])}
+			ifmat = append(ifmat, ifma.toAddr())
+		case *syscall.SockaddrInet6:
+			ifma := &IPAddr{IP: make(IP, IPv6len)}
+			copy(ifma.IP, v.Addr[:])
+			// NOTE: KAME based IPv6 protcol stack usually embeds
+			// the interface index in the interface-local or link-
+			// local address as the kernel-internal form.
+			if ifma.IP.IsInterfaceLocalMulticast() ||
+				ifma.IP.IsLinkLocalMulticast() {
+				// remove embedded scope zone ID
+				ifma.IP[2], ifma.IP[3] = 0, 0
+			}
+			ifmat = append(ifmat, ifma.toAddr())
+		}
+	}
+
+	return ifmat, nil
+}
diff --git a/src/pkg/net/interface_freebsd.go b/src/pkg/net/interface_freebsd.go
index e0ff6caf0..20f506b08 100644
--- a/src/pkg/net/interface_freebsd.go
+++ b/src/pkg/net/interface_freebsd.go
@@ -47,3 +47,34 @@ func interfaceMulticastAddrTable(ifindex int) ([]Addr, os.Error) {
 
 	return ifmat, nil
 }
+
+func newMulticastAddr(m *syscall.InterfaceMulticastAddrMessage) ([]Addr, os.Error) {
+	var ifmat []Addr
+
+	sas, e := syscall.ParseRoutingSockaddr(m)
+	if e != 0 {
+		return nil, os.NewSyscallError("route sockaddr", e)
+	}
+
+	for _, s := range sas {
+		switch v := s.(type) {
+		case *syscall.SockaddrInet4:
+			ifma := &IPAddr{IP: IPv4(v.Addr[0], v.Addr[1], v.Addr[2], v.Addr[3])}
+			ifmat = append(ifmat, ifma.toAddr())
+		case *syscall.SockaddrInet6:
+			ifma := &IPAddr{IP: make(IP, IPv6len)}
+			copy(ifma.IP, v.Addr[:])
+			// NOTE: KAME based IPv6 protcol stack usually embeds
+			// the interface index in the interface-local or link-
+			// local address as the kernel-internal form.
+			if ifma.IP.IsInterfaceLocalMulticast() ||
+				ifma.IP.IsLinkLocalMulticast() {
+				// remove embedded scope zone ID
+				ifma.IP[2], ifma.IP[3] = 0, 0
+			}
+			ifmat = append(ifmat, ifma.toAddr())
+		}
+	}
+
+	return ifmat, nil
+}
diff --git a/src/pkg/net/interface_openbsd.go b/src/pkg/net/interface_openbsd.go
new file mode 100644
index 000000000..f18149393
--- /dev/null
+++ b/src/pkg/net/interface_openbsd.go
@@ -0,0 +1,16 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Network interface identification for OpenBSD
+
+package net
+
+import "os"
+
+// If the ifindex is zero, interfaceMulticastAddrTable returns
+// addresses for all network interfaces.  Otherwise it returns
+// addresses for a specific interface.
+func interfaceMulticastAddrTable(ifindex int) ([]Addr, os.Error) {
+	return nil, nil
+}
diff --git a/src/pkg/net/iprawsock.go b/src/pkg/net/iprawsock.go
index 43047a78e..662b9f57b 100644
--- a/src/pkg/net/iprawsock.go
+++ b/src/pkg/net/iprawsock.go
@@ -8,22 +8,8 @@ package net
 
 import (
 	"os"
-	"sync"
-	"syscall"
 )
 
-var onceReadProtocols sync.Once
-
-func sockaddrToIP(sa syscall.Sockaddr) Addr {
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		return &IPAddr{sa.Addr[0:]}
-	case *syscall.SockaddrInet6:
-		return &IPAddr{sa.Addr[0:]}
-	}
-	return nil
-}
-
 // IPAddr represents the address of a IP end point.
 type IPAddr struct {
 	IP IP
@@ -39,27 +25,6 @@ func (a *IPAddr) String() string {
 	return a.IP.String()
 }
 
-func (a *IPAddr) family() int {
-	if a == nil || len(a.IP) <= 4 {
-		return syscall.AF_INET
-	}
-	if a.IP.To4() != nil {
-		return syscall.AF_INET
-	}
-	return syscall.AF_INET6
-}
-
-func (a *IPAddr) sockaddr(family int) (syscall.Sockaddr, os.Error) {
-	return ipToSockaddr(family, a.IP, 0)
-}
-
-func (a *IPAddr) toAddr() sockaddr {
-	if a == nil { // nil *IPAddr
-		return nil // nil interface
-	}
-	return a
-}
-
 // ResolveIPAddr parses addr as a IP address and resolves domain
 // names to numeric addresses on the network net, which must be
 // "ip", "ip4" or "ip6".  A literal IPv6 host address must be
@@ -72,168 +37,6 @@ func ResolveIPAddr(net, addr string) (*IPAddr, os.Error) {
 	return &IPAddr{ip}, nil
 }
 
-// IPConn is the implementation of the Conn and PacketConn
-// interfaces for IP network connections.
-type IPConn struct {
-	fd *netFD
-}
-
-func newIPConn(fd *netFD) *IPConn { return &IPConn{fd} }
-
-func (c *IPConn) ok() bool { return c != nil && c.fd != nil }
-
-// Implementation of the Conn interface - see Conn for documentation.
-
-// Read implements the net.Conn Read method.
-func (c *IPConn) Read(b []byte) (n int, err os.Error) {
-	n, _, err = c.ReadFrom(b)
-	return
-}
-
-// Write implements the net.Conn Write method.
-func (c *IPConn) Write(b []byte) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	return c.fd.Write(b)
-}
-
-// Close closes the IP connection.
-func (c *IPConn) Close() os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	err := c.fd.Close()
-	c.fd = nil
-	return err
-}
-
-// LocalAddr returns the local network address.
-func (c *IPConn) LocalAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.laddr
-}
-
-// RemoteAddr returns the remote network address, a *IPAddr.
-func (c *IPConn) RemoteAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.raddr
-}
-
-// SetTimeout implements the net.Conn SetTimeout method.
-func (c *IPConn) SetTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setTimeout(c.fd, nsec)
-}
-
-// SetReadTimeout implements the net.Conn SetReadTimeout method.
-func (c *IPConn) SetReadTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadTimeout(c.fd, nsec)
-}
-
-// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
-func (c *IPConn) SetWriteTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteTimeout(c.fd, nsec)
-}
-
-// SetReadBuffer sets the size of the operating system's
-// receive buffer associated with the connection.
-func (c *IPConn) SetReadBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadBuffer(c.fd, bytes)
-}
-
-// SetWriteBuffer sets the size of the operating system's
-// transmit buffer associated with the connection.
-func (c *IPConn) SetWriteBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteBuffer(c.fd, bytes)
-}
-
-// IP-specific methods.
-
-// ReadFromIP reads a IP packet from c, copying the payload into b.
-// It returns the number of bytes copied into b and the return address
-// that was on the packet.
-//
-// ReadFromIP can be made to time out and return an error with
-// Timeout() == true after a fixed time limit; see SetTimeout and
-// SetReadTimeout.
-func (c *IPConn) ReadFromIP(b []byte) (n int, addr *IPAddr, err os.Error) {
-	if !c.ok() {
-		return 0, nil, os.EINVAL
-	}
-	// TODO(cw,rsc): consider using readv if we know the family
-	// type to avoid the header trim/copy
-	n, sa, err := c.fd.ReadFrom(b)
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		addr = &IPAddr{sa.Addr[0:]}
-		if len(b) >= 4 { // discard ipv4 header
-			hsize := (int(b[0]) & 0xf) * 4
-			copy(b, b[hsize:])
-			n -= hsize
-		}
-	case *syscall.SockaddrInet6:
-		addr = &IPAddr{sa.Addr[0:]}
-	}
-	return
-}
-
-// ReadFrom implements the net.PacketConn ReadFrom method.
-func (c *IPConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
-	if !c.ok() {
-		return 0, nil, os.EINVAL
-	}
-	n, uaddr, err := c.ReadFromIP(b)
-	return n, uaddr.toAddr(), err
-}
-
-// WriteToIP writes a IP packet to addr via c, copying the payload from b.
-//
-// WriteToIP can be made to time out and return
-// an error with Timeout() == true after a fixed time limit;
-// see SetTimeout and SetWriteTimeout.
-// On packet-oriented connections, write timeouts are rare.
-func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	sa, err1 := addr.sockaddr(c.fd.family)
-	if err1 != nil {
-		return 0, &OpError{Op: "write", Net: "ip", Addr: addr, Error: err1}
-	}
-	return c.fd.WriteTo(b, sa)
-}
-
-// WriteTo implements the net.PacketConn WriteTo method.
-func (c *IPConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	a, ok := addr.(*IPAddr)
-	if !ok {
-		return 0, &OpError{"writeto", "ip", addr, os.EINVAL}
-	}
-	return c.WriteToIP(b, a)
-}
-
 // Convert "host" into IP address.
 func hostToIP(net, host string) (ip IP, err os.Error) {
 	var addr IP
@@ -264,100 +67,3 @@ func hostToIP(net, host string) (ip IP, err os.Error) {
 Error:
 	return nil, err
 }
-
-var protocols map[string]int
-
-func readProtocols() {
-	protocols = make(map[string]int)
-	if file, err := open("/etc/protocols"); err == nil {
-		for line, ok := file.readLine(); ok; line, ok = file.readLine() {
-			// tcp    6   TCP    # transmission control protocol
-			if i := byteIndex(line, '#'); i >= 0 {
-				line = line[0:i]
-			}
-			f := getFields(line)
-			if len(f) < 2 {
-				continue
-			}
-			if proto, _, ok := dtoi(f[1], 0); ok {
-				protocols[f[0]] = proto
-				for _, alias := range f[2:] {
-					protocols[alias] = proto
-				}
-			}
-		}
-		file.close()
-	}
-}
-
-func splitNetProto(netProto string) (net string, proto int, err os.Error) {
-	onceReadProtocols.Do(readProtocols)
-	i := last(netProto, ':')
-	if i < 0 { // no colon
-		return "", 0, os.NewError("no IP protocol specified")
-	}
-	net = netProto[0:i]
-	protostr := netProto[i+1:]
-	proto, i, ok := dtoi(protostr, 0)
-	if !ok || i != len(protostr) {
-		// lookup by name
-		proto, ok = protocols[protostr]
-		if ok {
-			return
-		}
-	}
-	return
-}
-
-// DialIP connects to the remote address raddr on the network net,
-// which must be "ip", "ip4", or "ip6".
-func DialIP(netProto string, laddr, raddr *IPAddr) (c *IPConn, err os.Error) {
-	net, proto, err := splitNetProto(netProto)
-	if err != nil {
-		return
-	}
-	switch net {
-	case "ip", "ip4", "ip6":
-	default:
-		return nil, UnknownNetworkError(net)
-	}
-	if raddr == nil {
-		return nil, &OpError{"dial", "ip", nil, errMissingAddress}
-	}
-	fd, e := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_RAW, proto, "dial", sockaddrToIP)
-	if e != nil {
-		return nil, e
-	}
-	return newIPConn(fd), nil
-}
-
-// ListenIP listens for incoming IP packets addressed to the
-// local address laddr.  The returned connection c's ReadFrom
-// and WriteTo methods can be used to receive and send IP
-// packets with per-packet addressing.
-func ListenIP(netProto string, laddr *IPAddr) (c *IPConn, err os.Error) {
-	net, proto, err := splitNetProto(netProto)
-	if err != nil {
-		return
-	}
-	switch net {
-	case "ip", "ip4", "ip6":
-	default:
-		return nil, UnknownNetworkError(net)
-	}
-	fd, e := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_RAW, proto, "dial", sockaddrToIP)
-	if e != nil {
-		return nil, e
-	}
-	return newIPConn(fd), nil
-}
-
-// BindToDevice binds an IPConn to a network interface.
-func (c *IPConn) BindToDevice(device string) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	c.fd.incref()
-	defer c.fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.BindToDevice(c.fd.sysfd, device))
-}
diff --git a/src/pkg/net/iprawsock_plan9.go b/src/pkg/net/iprawsock_plan9.go
new file mode 100644
index 000000000..808e17974
--- /dev/null
+++ b/src/pkg/net/iprawsock_plan9.go
@@ -0,0 +1,99 @@
+// Copyright 2010 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// (Raw) IP sockets stubs for Plan 9
+
+package net
+
+import (
+	"os"
+)
+
+// IPConn is the implementation of the Conn and PacketConn
+// interfaces for IP network connections.
+type IPConn bool
+
+// Implementation of the Conn interface - see Conn for documentation.
+
+// Read implements the net.Conn Read method.
+func (c *IPConn) Read(b []byte) (n int, err os.Error) {
+	return 0, os.EPLAN9
+}
+
+// Write implements the net.Conn Write method.
+func (c *IPConn) Write(b []byte) (n int, err os.Error) {
+	return 0, os.EPLAN9
+}
+
+// Close closes the IP connection.
+func (c *IPConn) Close() os.Error {
+	return os.EPLAN9
+}
+
+// LocalAddr returns the local network address.
+func (c *IPConn) LocalAddr() Addr {
+	return nil
+}
+
+// RemoteAddr returns the remote network address, a *IPAddr.
+func (c *IPConn) RemoteAddr() Addr {
+	return nil
+}
+
+// SetTimeout implements the net.Conn SetTimeout method.
+func (c *IPConn) SetTimeout(nsec int64) os.Error {
+	return os.EPLAN9
+}
+
+// SetReadTimeout implements the net.Conn SetReadTimeout method.
+func (c *IPConn) SetReadTimeout(nsec int64) os.Error {
+	return os.EPLAN9
+}
+
+// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
+func (c *IPConn) SetWriteTimeout(nsec int64) os.Error {
+	return os.EPLAN9
+}
+
+// IP-specific methods.
+
+// ReadFrom implements the net.PacketConn ReadFrom method.
+func (c *IPConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
+	err = os.EPLAN9
+	return
+}
+
+// WriteToIP writes a IP packet to addr via c, copying the payload from b.
+//
+// WriteToIP can be made to time out and return
+// an error with Timeout() == true after a fixed time limit;
+// see SetTimeout and SetWriteTimeout.
+// On packet-oriented connections, write timeouts are rare.
+func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (n int, err os.Error) {
+	return 0, os.EPLAN9
+}
+
+// WriteTo implements the net.PacketConn WriteTo method.
+func (c *IPConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
+	return 0, os.EPLAN9
+}
+
+func splitNetProto(netProto string) (net string, proto int, err os.Error) {
+	err = os.EPLAN9
+	return
+}
+
+// DialIP connects to the remote address raddr on the network net,
+// which must be "ip", "ip4", or "ip6".
+func DialIP(netProto string, laddr, raddr *IPAddr) (c *IPConn, err os.Error) {
+	return nil, os.EPLAN9
+}
+
+// ListenIP listens for incoming IP packets addressed to the
+// local address laddr.  The returned connection c's ReadFrom
+// and WriteTo methods can be used to receive and send IP
+// packets with per-packet addressing.
+func ListenIP(netProto string, laddr *IPAddr) (c *IPConn, err os.Error) {
+	return nil, os.EPLAN9
+}
diff --git a/src/pkg/net/iprawsock_posix.go b/src/pkg/net/iprawsock_posix.go
new file mode 100644
index 000000000..4e1151800
--- /dev/null
+++ b/src/pkg/net/iprawsock_posix.go
@@ -0,0 +1,305 @@
+// Copyright 2010 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// (Raw) IP sockets
+
+package net
+
+import (
+	"os"
+	"sync"
+	"syscall"
+)
+
+var onceReadProtocols sync.Once
+
+func sockaddrToIP(sa syscall.Sockaddr) Addr {
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		return &IPAddr{sa.Addr[0:]}
+	case *syscall.SockaddrInet6:
+		return &IPAddr{sa.Addr[0:]}
+	}
+	return nil
+}
+
+func (a *IPAddr) family() int {
+	if a == nil || len(a.IP) <= 4 {
+		return syscall.AF_INET
+	}
+	if a.IP.To4() != nil {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+func (a *IPAddr) sockaddr(family int) (syscall.Sockaddr, os.Error) {
+	return ipToSockaddr(family, a.IP, 0)
+}
+
+func (a *IPAddr) toAddr() sockaddr {
+	if a == nil { // nil *IPAddr
+		return nil // nil interface
+	}
+	return a
+}
+
+// IPConn is the implementation of the Conn and PacketConn
+// interfaces for IP network connections.
+type IPConn struct {
+	fd *netFD
+}
+
+func newIPConn(fd *netFD) *IPConn { return &IPConn{fd} }
+
+func (c *IPConn) ok() bool { return c != nil && c.fd != nil }
+
+// Implementation of the Conn interface - see Conn for documentation.
+
+// Read implements the net.Conn Read method.
+func (c *IPConn) Read(b []byte) (n int, err os.Error) {
+	n, _, err = c.ReadFrom(b)
+	return
+}
+
+// Write implements the net.Conn Write method.
+func (c *IPConn) Write(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	return c.fd.Write(b)
+}
+
+// Close closes the IP connection.
+func (c *IPConn) Close() os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	err := c.fd.Close()
+	c.fd = nil
+	return err
+}
+
+// LocalAddr returns the local network address.
+func (c *IPConn) LocalAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.laddr
+}
+
+// RemoteAddr returns the remote network address, a *IPAddr.
+func (c *IPConn) RemoteAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.raddr
+}
+
+// SetTimeout implements the net.Conn SetTimeout method.
+func (c *IPConn) SetTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setTimeout(c.fd, nsec)
+}
+
+// SetReadTimeout implements the net.Conn SetReadTimeout method.
+func (c *IPConn) SetReadTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadTimeout(c.fd, nsec)
+}
+
+// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
+func (c *IPConn) SetWriteTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteTimeout(c.fd, nsec)
+}
+
+// SetReadBuffer sets the size of the operating system's
+// receive buffer associated with the connection.
+func (c *IPConn) SetReadBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadBuffer(c.fd, bytes)
+}
+
+// SetWriteBuffer sets the size of the operating system's
+// transmit buffer associated with the connection.
+func (c *IPConn) SetWriteBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteBuffer(c.fd, bytes)
+}
+
+// IP-specific methods.
+
+// ReadFromIP reads a IP packet from c, copying the payload into b.
+// It returns the number of bytes copied into b and the return address
+// that was on the packet.
+//
+// ReadFromIP can be made to time out and return an error with
+// Timeout() == true after a fixed time limit; see SetTimeout and
+// SetReadTimeout.
+func (c *IPConn) ReadFromIP(b []byte) (n int, addr *IPAddr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	// TODO(cw,rsc): consider using readv if we know the family
+	// type to avoid the header trim/copy
+	n, sa, err := c.fd.ReadFrom(b)
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		addr = &IPAddr{sa.Addr[0:]}
+		if len(b) >= 4 { // discard ipv4 header
+			hsize := (int(b[0]) & 0xf) * 4
+			copy(b, b[hsize:])
+			n -= hsize
+		}
+	case *syscall.SockaddrInet6:
+		addr = &IPAddr{sa.Addr[0:]}
+	}
+	return
+}
+
+// ReadFrom implements the net.PacketConn ReadFrom method.
+func (c *IPConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	n, uaddr, err := c.ReadFromIP(b)
+	return n, uaddr.toAddr(), err
+}
+
+// WriteToIP writes a IP packet to addr via c, copying the payload from b.
+//
+// WriteToIP can be made to time out and return
+// an error with Timeout() == true after a fixed time limit;
+// see SetTimeout and SetWriteTimeout.
+// On packet-oriented connections, write timeouts are rare.
+func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	sa, err1 := addr.sockaddr(c.fd.family)
+	if err1 != nil {
+		return 0, &OpError{Op: "write", Net: "ip", Addr: addr, Error: err1}
+	}
+	return c.fd.WriteTo(b, sa)
+}
+
+// WriteTo implements the net.PacketConn WriteTo method.
+func (c *IPConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	a, ok := addr.(*IPAddr)
+	if !ok {
+		return 0, &OpError{"writeto", "ip", addr, os.EINVAL}
+	}
+	return c.WriteToIP(b, a)
+}
+
+var protocols map[string]int
+
+func readProtocols() {
+	protocols = make(map[string]int)
+	if file, err := open("/etc/protocols"); err == nil {
+		for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+			// tcp    6   TCP    # transmission control protocol
+			if i := byteIndex(line, '#'); i >= 0 {
+				line = line[0:i]
+			}
+			f := getFields(line)
+			if len(f) < 2 {
+				continue
+			}
+			if proto, _, ok := dtoi(f[1], 0); ok {
+				protocols[f[0]] = proto
+				for _, alias := range f[2:] {
+					protocols[alias] = proto
+				}
+			}
+		}
+		file.close()
+	}
+}
+
+func splitNetProto(netProto string) (net string, proto int, err os.Error) {
+	onceReadProtocols.Do(readProtocols)
+	i := last(netProto, ':')
+	if i < 0 { // no colon
+		return "", 0, os.NewError("no IP protocol specified")
+	}
+	net = netProto[0:i]
+	protostr := netProto[i+1:]
+	proto, i, ok := dtoi(protostr, 0)
+	if !ok || i != len(protostr) {
+		// lookup by name
+		proto, ok = protocols[protostr]
+		if ok {
+			return
+		}
+	}
+	return
+}
+
+// DialIP connects to the remote address raddr on the network net,
+// which must be "ip", "ip4", or "ip6".
+func DialIP(netProto string, laddr, raddr *IPAddr) (c *IPConn, err os.Error) {
+	net, proto, err := splitNetProto(netProto)
+	if err != nil {
+		return
+	}
+	switch net {
+	case "ip", "ip4", "ip6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if raddr == nil {
+		return nil, &OpError{"dial", "ip", nil, errMissingAddress}
+	}
+	fd, e := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_RAW, proto, "dial", sockaddrToIP)
+	if e != nil {
+		return nil, e
+	}
+	return newIPConn(fd), nil
+}
+
+// ListenIP listens for incoming IP packets addressed to the
+// local address laddr.  The returned connection c's ReadFrom
+// and WriteTo methods can be used to receive and send IP
+// packets with per-packet addressing.
+func ListenIP(netProto string, laddr *IPAddr) (c *IPConn, err os.Error) {
+	net, proto, err := splitNetProto(netProto)
+	if err != nil {
+		return
+	}
+	switch net {
+	case "ip", "ip4", "ip6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	fd, e := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_RAW, proto, "dial", sockaddrToIP)
+	if e != nil {
+		return nil, e
+	}
+	return newIPConn(fd), nil
+}
+
+// BindToDevice binds an IPConn to a network interface.
+func (c *IPConn) BindToDevice(device string) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	c.fd.incref()
+	defer c.fd.decref()
+	return os.NewSyscallError("setsockopt", syscall.BindToDevice(c.fd.sysfd, device))
+}
diff --git a/src/pkg/net/ipsock.go b/src/pkg/net/ipsock.go
index e831d9afc..4e2a5622b 100644
--- a/src/pkg/net/ipsock.go
+++ b/src/pkg/net/ipsock.go
@@ -8,94 +8,10 @@ package net
 
 import (
 	"os"
-	"syscall"
 )
 
-// Should we try to use the IPv4 socket interface if we're
-// only dealing with IPv4 sockets?  As long as the host system
-// understands IPv6, it's okay to pass IPv4 addresses to the IPv6
-// interface.  That simplifies our code and is most general.
-// Unfortunately, we need to run on kernels built without IPv6
-// support too.  So probe the kernel to figure it out.
-//
-// probeIPv6Stack probes both basic IPv6 capability and IPv6 IPv4-
-// mapping capability which is controlled by IPV6_V6ONLY socket
-// option and/or kernel state "net.inet6.ip6.v6only".
-// It returns two boolean values.  If the first boolean value is
-// true, kernel supports basic IPv6 functionality.  If the second
-// boolean value is true, kernel supports IPv6 IPv4-mapping.
-func probeIPv6Stack() (supportsIPv6, supportsIPv4map bool) {
-	var probes = []struct {
-		la TCPAddr
-		ok bool
-	}{
-		// IPv6 communication capability
-		{TCPAddr{IP: ParseIP("::1")}, false},
-		// IPv6 IPv4-mapped address communication capability
-		{TCPAddr{IP: IPv4(127, 0, 0, 1)}, false},
-	}
-
-	for i := range probes {
-		s, errno := syscall.Socket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
-		if errno != 0 {
-			continue
-		}
-		defer closesocket(s)
-		sa, err := probes[i].la.toAddr().sockaddr(syscall.AF_INET6)
-		if err != nil {
-			continue
-		}
-		errno = syscall.Bind(s, sa)
-		if errno != 0 {
-			continue
-		}
-		probes[i].ok = true
-	}
-
-	return probes[0].ok, probes[1].ok
-}
-
 var supportsIPv6, supportsIPv4map = probeIPv6Stack()
 
-// favoriteAddrFamily returns the appropriate address family to
-// the given net, raddr, laddr and mode.  At first it figures
-// address family out from the net.  If mode indicates "listen"
-// and laddr.(type).IP is nil, it assumes that the user wants to
-// make a passive connection with wildcard address family, both
-// INET and INET6, and wildcard address.  Otherwise guess: if the
-// addresses are IPv4 then returns INET, or else returns INET6.
-func favoriteAddrFamily(net string, raddr, laddr sockaddr, mode string) int {
-	switch net[len(net)-1] {
-	case '4':
-		return syscall.AF_INET
-	case '6':
-		return syscall.AF_INET6
-	}
-
-	if mode == "listen" {
-		switch a := laddr.(type) {
-		case *TCPAddr:
-			if a.IP == nil && supportsIPv6 {
-				return syscall.AF_INET6
-			}
-		case *UDPAddr:
-			if a.IP == nil && supportsIPv6 {
-				return syscall.AF_INET6
-			}
-		case *IPAddr:
-			if a.IP == nil && supportsIPv6 {
-				return syscall.AF_INET6
-			}
-		}
-	}
-
-	if (laddr == nil || laddr.family() == syscall.AF_INET) &&
-		(raddr == nil || raddr.family() == syscall.AF_INET) {
-		return syscall.AF_INET
-	}
-	return syscall.AF_INET6
-}
-
 func firstFavoriteAddr(filter func(IP) IP, addrs []string) (addr IP) {
 	if filter == anyaddr {
 		// We'll take any IP address, but since the dialing code
@@ -143,93 +59,12 @@ func ipv6only(x IP) IP {
 	return nil
 }
 
-// TODO(rsc): if syscall.OS == "linux", we're supposed to read
-// /proc/sys/net/core/somaxconn,
-// to take advantage of kernels that have raised the limit.
-func listenBacklog() int { return syscall.SOMAXCONN }
-
-// Internet sockets (TCP, UDP)
-
-// A sockaddr represents a TCP or UDP network address that can
-// be converted into a syscall.Sockaddr.
-type sockaddr interface {
-	Addr
-	sockaddr(family int) (syscall.Sockaddr, os.Error)
-	family() int
-}
-
-func internetSocket(net string, laddr, raddr sockaddr, socktype, proto int, mode string, toAddr func(syscall.Sockaddr) Addr) (fd *netFD, err os.Error) {
-	var oserr os.Error
-	var la, ra syscall.Sockaddr
-	family := favoriteAddrFamily(net, raddr, laddr, mode)
-	if laddr != nil {
-		if la, oserr = laddr.sockaddr(family); oserr != nil {
-			goto Error
-		}
-	}
-	if raddr != nil {
-		if ra, oserr = raddr.sockaddr(family); oserr != nil {
-			goto Error
-		}
-	}
-	fd, oserr = socket(net, family, socktype, proto, la, ra, toAddr)
-	if oserr != nil {
-		goto Error
-	}
-	return fd, nil
-
-Error:
-	addr := raddr
-	if mode == "listen" {
-		addr = laddr
-	}
-	return nil, &OpError{mode, net, addr, oserr}
-}
-
 type InvalidAddrError string
 
 func (e InvalidAddrError) String() string  { return string(e) }
 func (e InvalidAddrError) Timeout() bool   { return false }
 func (e InvalidAddrError) Temporary() bool { return false }
 
-func ipToSockaddr(family int, ip IP, port int) (syscall.Sockaddr, os.Error) {
-	switch family {
-	case syscall.AF_INET:
-		if len(ip) == 0 {
-			ip = IPv4zero
-		}
-		if ip = ip.To4(); ip == nil {
-			return nil, InvalidAddrError("non-IPv4 address")
-		}
-		s := new(syscall.SockaddrInet4)
-		for i := 0; i < IPv4len; i++ {
-			s.Addr[i] = ip[i]
-		}
-		s.Port = port
-		return s, nil
-	case syscall.AF_INET6:
-		if len(ip) == 0 {
-			ip = IPv6zero
-		}
-		// IPv4 callers use 0.0.0.0 to mean "announce on any available address".
-		// In IPv6 mode, Linux treats that as meaning "announce on 0.0.0.0",
-		// which it refuses to do.  Rewrite to the IPv6 all zeros.
-		if ip.Equal(IPv4zero) {
-			ip = IPv6zero
-		}
-		if ip = ip.To16(); ip == nil {
-			return nil, InvalidAddrError("non-IPv6 address")
-		}
-		s := new(syscall.SockaddrInet6)
-		for i := 0; i < IPv6len; i++ {
-			s.Addr[i] = ip[i]
-		}
-		s.Port = port
-		return s, nil
-	}
-	return nil, InvalidAddrError("unexpected socket family")
-}
-
 // SplitHostPort splits a network address of the form
 // "host:port" or "[host]:port" into host and port.
 // The latter form must be used when host contains a colon.
diff --git a/src/pkg/net/ipsock_plan9.go b/src/pkg/net/ipsock_plan9.go
new file mode 100644
index 000000000..9e5da6d38
--- /dev/null
+++ b/src/pkg/net/ipsock_plan9.go
@@ -0,0 +1,305 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// IP sockets stubs for Plan 9
+
+package net
+
+import (
+	"os"
+)
+
+// probeIPv6Stack returns two boolean values.  If the first boolean value is
+// true, kernel supports basic IPv6 functionality.  If the second
+// boolean value is true, kernel supports IPv6 IPv4-mapping.
+func probeIPv6Stack() (supportsIPv6, supportsIPv4map bool) {
+	return false, false
+}
+
+// parsePlan9Addr parses address of the form [ip!]port (e.g. 127.0.0.1!80).
+func parsePlan9Addr(s string) (ip IP, iport int, err os.Error) {
+	var (
+		addr IP
+		p, i int
+		ok   bool
+	)
+	addr = IPv4zero // address contains port only
+	i = byteIndex(s, '!')
+	if i >= 0 {
+		addr = ParseIP(s[:i])
+		if addr == nil {
+			err = os.NewError("net: parsing IP failed")
+			goto Error
+		}
+	}
+	p, _, ok = dtoi(s[i+1:], 0)
+	if !ok {
+		err = os.NewError("net: parsing port failed")
+		goto Error
+	}
+	if p < 0 || p > 0xFFFF {
+		err = &AddrError{"invalid port", string(p)}
+		goto Error
+	}
+	return addr, p, nil
+
+Error:
+	return nil, 0, err
+}
+
+func readPlan9Addr(proto, filename string) (addr Addr, err os.Error) {
+	var buf [128]byte
+
+	f, err := os.Open(filename)
+	if err != nil {
+		return
+	}
+	n, err := f.Read(buf[:])
+	if err != nil {
+		return
+	}
+	ip, port, err := parsePlan9Addr(string(buf[:n]))
+	if err != nil {
+		return
+	}
+	switch proto {
+	case "tcp":
+		addr = &TCPAddr{ip, port}
+	case "udp":
+		addr = &UDPAddr{ip, port}
+	default:
+		return nil, os.NewError("unknown protocol " + proto)
+	}
+	return addr, nil
+}
+
+type plan9Conn struct {
+	proto, name, dir string
+	ctl, data        *os.File
+	laddr, raddr     Addr
+}
+
+func newPlan9Conn(proto, name string, ctl *os.File, laddr, raddr Addr) *plan9Conn {
+	return &plan9Conn{proto, name, "/net/" + proto + "/" + name, ctl, nil, laddr, raddr}
+}
+
+func (c *plan9Conn) ok() bool { return c != nil && c.ctl != nil }
+
+// Implementation of the Conn interface - see Conn for documentation.
+
+// Read implements the net.Conn Read method.
+func (c *plan9Conn) Read(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	if c.data == nil {
+		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
+		if err != nil {
+			return 0, err
+		}
+	}
+	n, err = c.data.Read(b)
+	if c.proto == "udp" && err == os.EOF {
+		n = 0
+		err = nil
+	}
+	return
+}
+
+// Write implements the net.Conn Write method.
+func (c *plan9Conn) Write(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	if c.data == nil {
+		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
+		if err != nil {
+			return 0, err
+		}
+	}
+	return c.data.Write(b)
+}
+
+// Close closes the connection.
+func (c *plan9Conn) Close() os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	err := c.ctl.Close()
+	if err != nil {
+		return err
+	}
+	if c.data != nil {
+		err = c.data.Close()
+	}
+	c.ctl = nil
+	c.data = nil
+	return err
+}
+
+// LocalAddr returns the local network address.
+func (c *plan9Conn) LocalAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.laddr
+}
+
+// RemoteAddr returns the remote network address.
+func (c *plan9Conn) RemoteAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.raddr
+}
+
+// SetTimeout implements the net.Conn SetTimeout method.
+func (c *plan9Conn) SetTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return os.EPLAN9
+}
+
+// SetReadTimeout implements the net.Conn SetReadTimeout method.
+func (c *plan9Conn) SetReadTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return os.EPLAN9
+}
+
+// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
+func (c *plan9Conn) SetWriteTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return os.EPLAN9
+}
+
+func startPlan9(net string, addr Addr) (ctl *os.File, dest, proto, name string, err os.Error) {
+	var (
+		ip   IP
+		port int
+	)
+	switch a := addr.(type) {
+	case *TCPAddr:
+		proto = "tcp"
+		ip = a.IP
+		port = a.Port
+	case *UDPAddr:
+		proto = "udp"
+		ip = a.IP
+		port = a.Port
+	default:
+		err = UnknownNetworkError(net)
+		return
+	}
+
+	clone, dest, err := queryCS1(proto, ip, port)
+	if err != nil {
+		return
+	}
+	f, err := os.OpenFile(clone, os.O_RDWR, 0)
+	if err != nil {
+		return
+	}
+	var buf [16]byte
+	n, err := f.Read(buf[:])
+	if err != nil {
+		return
+	}
+	return f, dest, proto, string(buf[:n]), nil
+}
+
+func dialPlan9(net string, laddr, raddr Addr) (c *plan9Conn, err os.Error) {
+	f, dest, proto, name, err := startPlan9(net, raddr)
+	if err != nil {
+		return
+	}
+	_, err = f.WriteString("connect " + dest)
+	if err != nil {
+		return
+	}
+	laddr, err = readPlan9Addr(proto, "/net/"+proto+"/"+name+"/local")
+	if err != nil {
+		return
+	}
+	raddr, err = readPlan9Addr(proto, "/net/"+proto+"/"+name+"/remote")
+	if err != nil {
+		return
+	}
+	return newPlan9Conn(proto, name, f, laddr, raddr), nil
+}
+
+type plan9Listener struct {
+	proto, name, dir string
+	ctl              *os.File
+	laddr            Addr
+}
+
+func listenPlan9(net string, laddr Addr) (l *plan9Listener, err os.Error) {
+	f, dest, proto, name, err := startPlan9(net, laddr)
+	if err != nil {
+		return
+	}
+	_, err = f.WriteString("announce " + dest)
+	if err != nil {
+		return
+	}
+	laddr, err = readPlan9Addr(proto, "/net/"+proto+"/"+name+"/local")
+	if err != nil {
+		return
+	}
+	l = new(plan9Listener)
+	l.proto = proto
+	l.name = name
+	l.dir = "/net/" + proto + "/" + name
+	l.ctl = f
+	l.laddr = laddr
+	return l, nil
+}
+
+func (l *plan9Listener) plan9Conn() *plan9Conn {
+	return newPlan9Conn(l.proto, l.name, l.ctl, l.laddr, nil)
+}
+
+func (l *plan9Listener) acceptPlan9() (c *plan9Conn, err os.Error) {
+	f, err := os.Open(l.dir + "/listen")
+	if err != nil {
+		return
+	}
+	var buf [16]byte
+	n, err := f.Read(buf[:])
+	if err != nil {
+		return
+	}
+	name := string(buf[:n])
+	laddr, err := readPlan9Addr(l.proto, l.dir+"/local")
+	if err != nil {
+		return
+	}
+	raddr, err := readPlan9Addr(l.proto, l.dir+"/remote")
+	if err != nil {
+		return
+	}
+	return newPlan9Conn(l.proto, name, f, laddr, raddr), nil
+}
+
+func (l *plan9Listener) Accept() (c Conn, err os.Error) {
+	c1, err := l.acceptPlan9()
+	if err != nil {
+		return
+	}
+	return c1, nil
+}
+
+func (l *plan9Listener) Close() os.Error {
+	if l == nil || l.ctl == nil {
+		return os.EINVAL
+	}
+	return l.ctl.Close()
+}
+
+func (l *plan9Listener) Addr() Addr { return l.laddr }
diff --git a/src/pkg/net/ipsock_posix.go b/src/pkg/net/ipsock_posix.go
new file mode 100644
index 000000000..0c522fb7f
--- /dev/null
+++ b/src/pkg/net/ipsock_posix.go
@@ -0,0 +1,174 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"os"
+	"syscall"
+)
+
+// Should we try to use the IPv4 socket interface if we're
+// only dealing with IPv4 sockets?  As long as the host system
+// understands IPv6, it's okay to pass IPv4 addresses to the IPv6
+// interface.  That simplifies our code and is most general.
+// Unfortunately, we need to run on kernels built without IPv6
+// support too.  So probe the kernel to figure it out.
+//
+// probeIPv6Stack probes both basic IPv6 capability and IPv6 IPv4-
+// mapping capability which is controlled by IPV6_V6ONLY socket
+// option and/or kernel state "net.inet6.ip6.v6only".
+// It returns two boolean values.  If the first boolean value is
+// true, kernel supports basic IPv6 functionality.  If the second
+// boolean value is true, kernel supports IPv6 IPv4-mapping.
+func probeIPv6Stack() (supportsIPv6, supportsIPv4map bool) {
+	var probes = []struct {
+		la TCPAddr
+		ok bool
+	}{
+		// IPv6 communication capability
+		{TCPAddr{IP: ParseIP("::1")}, false},
+		// IPv6 IPv4-mapped address communication capability
+		{TCPAddr{IP: IPv4(127, 0, 0, 1)}, false},
+	}
+
+	for i := range probes {
+		s, errno := syscall.Socket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
+		if errno != 0 {
+			continue
+		}
+		defer closesocket(s)
+		sa, err := probes[i].la.toAddr().sockaddr(syscall.AF_INET6)
+		if err != nil {
+			continue
+		}
+		errno = syscall.Bind(s, sa)
+		if errno != 0 {
+			continue
+		}
+		probes[i].ok = true
+	}
+
+	return probes[0].ok, probes[1].ok
+}
+
+// favoriteAddrFamily returns the appropriate address family to
+// the given net, raddr, laddr and mode.  At first it figures
+// address family out from the net.  If mode indicates "listen"
+// and laddr.(type).IP is nil, it assumes that the user wants to
+// make a passive connection with wildcard address family, both
+// INET and INET6, and wildcard address.  Otherwise guess: if the
+// addresses are IPv4 then returns INET, or else returns INET6.
+func favoriteAddrFamily(net string, raddr, laddr sockaddr, mode string) int {
+	switch net[len(net)-1] {
+	case '4':
+		return syscall.AF_INET
+	case '6':
+		return syscall.AF_INET6
+	}
+
+	if mode == "listen" {
+		switch a := laddr.(type) {
+		case *TCPAddr:
+			if a.IP == nil && supportsIPv6 {
+				return syscall.AF_INET6
+			}
+		case *UDPAddr:
+			if a.IP == nil && supportsIPv6 {
+				return syscall.AF_INET6
+			}
+		case *IPAddr:
+			if a.IP == nil && supportsIPv6 {
+				return syscall.AF_INET6
+			}
+		}
+	}
+
+	if (laddr == nil || laddr.family() == syscall.AF_INET) &&
+		(raddr == nil || raddr.family() == syscall.AF_INET) {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+// TODO(rsc): if syscall.OS == "linux", we're supposed to read
+// /proc/sys/net/core/somaxconn,
+// to take advantage of kernels that have raised the limit.
+func listenBacklog() int { return syscall.SOMAXCONN }
+
+// Internet sockets (TCP, UDP)
+
+// A sockaddr represents a TCP or UDP network address that can
+// be converted into a syscall.Sockaddr.
+type sockaddr interface {
+	Addr
+	sockaddr(family int) (syscall.Sockaddr, os.Error)
+	family() int
+}
+
+func internetSocket(net string, laddr, raddr sockaddr, socktype, proto int, mode string, toAddr func(syscall.Sockaddr) Addr) (fd *netFD, err os.Error) {
+	var oserr os.Error
+	var la, ra syscall.Sockaddr
+	family := favoriteAddrFamily(net, raddr, laddr, mode)
+	if laddr != nil {
+		if la, oserr = laddr.sockaddr(family); oserr != nil {
+			goto Error
+		}
+	}
+	if raddr != nil {
+		if ra, oserr = raddr.sockaddr(family); oserr != nil {
+			goto Error
+		}
+	}
+	fd, oserr = socket(net, family, socktype, proto, la, ra, toAddr)
+	if oserr != nil {
+		goto Error
+	}
+	return fd, nil
+
+Error:
+	addr := raddr
+	if mode == "listen" {
+		addr = laddr
+	}
+	return nil, &OpError{mode, net, addr, oserr}
+}
+
+func ipToSockaddr(family int, ip IP, port int) (syscall.Sockaddr, os.Error) {
+	switch family {
+	case syscall.AF_INET:
+		if len(ip) == 0 {
+			ip = IPv4zero
+		}
+		if ip = ip.To4(); ip == nil {
+			return nil, InvalidAddrError("non-IPv4 address")
+		}
+		s := new(syscall.SockaddrInet4)
+		for i := 0; i < IPv4len; i++ {
+			s.Addr[i] = ip[i]
+		}
+		s.Port = port
+		return s, nil
+	case syscall.AF_INET6:
+		if len(ip) == 0 {
+			ip = IPv6zero
+		}
+		// IPv4 callers use 0.0.0.0 to mean "announce on any available address".
+		// In IPv6 mode, Linux treats that as meaning "announce on 0.0.0.0",
+		// which it refuses to do.  Rewrite to the IPv6 all zeros.
+		if ip.Equal(IPv4zero) {
+			ip = IPv6zero
+		}
+		if ip = ip.To16(); ip == nil {
+			return nil, InvalidAddrError("non-IPv6 address")
+		}
+		s := new(syscall.SockaddrInet6)
+		for i := 0; i < IPv6len; i++ {
+			s.Addr[i] = ip[i]
+		}
+		s.Port = port
+		return s, nil
+	}
+	return nil, InvalidAddrError("unexpected socket family")
+}
diff --git a/src/pkg/net/lookup_plan9.go b/src/pkg/net/lookup_plan9.go
new file mode 100644
index 000000000..37d6b8e31
--- /dev/null
+++ b/src/pkg/net/lookup_plan9.go
@@ -0,0 +1,226 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"os"
+)
+
+func query(filename, query string, bufSize int) (res []string, err os.Error) {
+	file, err := os.OpenFile(filename, os.O_RDWR, 0)
+	if err != nil {
+		return
+	}
+	defer file.Close()
+
+	_, err = file.WriteString(query)
+	if err != nil {
+		return
+	}
+	_, err = file.Seek(0, 0)
+	if err != nil {
+		return
+	}
+	buf := make([]byte, bufSize)
+	for {
+		n, _ := file.Read(buf)
+		if n <= 0 {
+			break
+		}
+		res = append(res, string(buf[:n]))
+	}
+	return
+}
+
+func queryCS(net, host, service string) (res []string, err os.Error) {
+	switch net {
+	case "tcp4", "tcp6":
+		net = "tcp"
+	case "udp4", "udp6":
+		net = "udp"
+	}
+	if host == "" {
+		host = "*"
+	}
+	return query("/net/cs", net+"!"+host+"!"+service, 128)
+}
+
+func queryCS1(net string, ip IP, port int) (clone, dest string, err os.Error) {
+	ips := "*"
+	if !ip.IsUnspecified() {
+		ips = ip.String()
+	}
+	lines, err := queryCS(net, ips, itoa(port))
+	if err != nil {
+		return
+	}
+	f := getFields(lines[0])
+	if len(f) < 2 {
+		return "", "", os.NewError("net: bad response from ndb/cs")
+	}
+	clone, dest = f[0], f[1]
+	return
+}
+
+func queryDNS(addr string, typ string) (res []string, err os.Error) {
+	return query("/net/dns", addr+" "+typ, 1024)
+}
+
+// LookupHost looks up the given host using the local resolver.
+// It returns an array of that host's addresses.
+func LookupHost(host string) (addrs []string, err os.Error) {
+	// Use /net/cs insead of /net/dns because cs knows about
+	// host names in local network (e.g. from /lib/ndb/local)
+	lines, err := queryCS("tcp", host, "1")
+	if err != nil {
+		return
+	}
+	for _, line := range lines {
+		f := getFields(line)
+		if len(f) < 2 {
+			continue
+		}
+		addr := f[1]
+		if i := byteIndex(addr, '!'); i >= 0 {
+			addr = addr[:i] // remove port
+		}
+		if ParseIP(addr) == nil {
+			continue
+		}
+		addrs = append(addrs, addr)
+	}
+	return
+}
+
+// LookupIP looks up host using the local resolver.
+// It returns an array of that host's IPv4 and IPv6 addresses.
+func LookupIP(host string) (ips []IP, err os.Error) {
+	addrs, err := LookupHost(host)
+	if err != nil {
+		return
+	}
+	for _, addr := range addrs {
+		if ip := ParseIP(addr); ip != nil {
+			ips = append(ips, ip)
+		}
+	}
+	return
+}
+
+// LookupPort looks up the port for the given network and service.
+func LookupPort(network, service string) (port int, err os.Error) {
+	switch network {
+	case "tcp4", "tcp6":
+		network = "tcp"
+	case "udp4", "udp6":
+		network = "udp"
+	}
+	lines, err := queryCS(network, "127.0.0.1", service)
+	if err != nil {
+		return
+	}
+	unknownPortError := &AddrError{"unknown port", network + "/" + service}
+	if len(lines) == 0 {
+		return 0, unknownPortError
+	}
+	f := getFields(lines[0])
+	if len(f) < 2 {
+		return 0, unknownPortError
+	}
+	s := f[1]
+	if i := byteIndex(s, '!'); i >= 0 {
+		s = s[i+1:] // remove address
+	}
+	if n, _, ok := dtoi(s, 0); ok {
+		return n, nil
+	}
+	return 0, unknownPortError
+}
+
+// LookupCNAME returns the canonical DNS host for the given name.
+// Callers that do not care about the canonical name can call
+// LookupHost or LookupIP directly; both take care of resolving
+// the canonical name as part of the lookup.
+func LookupCNAME(name string) (cname string, err os.Error) {
+	lines, err := queryDNS(name, "cname")
+	if err != nil {
+		return
+	}
+	if len(lines) > 0 {
+		if f := getFields(lines[0]); len(f) >= 3 {
+			return f[2] + ".", nil
+		}
+	}
+	return "", os.NewError("net: bad response from ndb/dns")
+}
+
+// LookupSRV tries to resolve an SRV query of the given service,
+// protocol, and domain name, as specified in RFC 2782. In most cases
+// the proto argument can be the same as the corresponding
+// Addr.Network(). The returned records are sorted by priority 
+// and randomized by weight within a priority.
+func LookupSRV(service, proto, name string) (cname string, addrs []*SRV, err os.Error) {
+	target := "_" + service + "._" + proto + "." + name
+	lines, err := queryDNS(target, "srv")
+	if err != nil {
+		return
+	}
+	for _, line := range lines {
+		f := getFields(line)
+		if len(f) < 6 {
+			continue
+		}
+		port, _, portOk := dtoi(f[2], 0)
+		priority, _, priorityOk := dtoi(f[3], 0)
+		weight, _, weightOk := dtoi(f[4], 0)
+		if !(portOk && priorityOk && weightOk) {
+			continue
+		}
+		addrs = append(addrs, &SRV{f[5], uint16(port), uint16(priority), uint16(weight)})
+		cname = f[0]
+	}
+	byPriorityWeight(addrs).sort()
+	return
+}
+
+// LookupMX returns the DNS MX records for the given domain name sorted by preference.
+func LookupMX(name string) (mx []*MX, err os.Error) {
+	lines, err := queryDNS(name, "mx")
+	if err != nil {
+		return
+	}
+	for _, line := range lines {
+		f := getFields(line)
+		if len(f) < 4 {
+			continue
+		}
+		if pref, _, ok := dtoi(f[2], 0); ok {
+			mx = append(mx, &MX{f[3], uint16(pref)})
+		}
+	}
+	byPref(mx).sort()
+	return
+}
+
+// LookupAddr performs a reverse lookup for the given address, returning a list
+// of names mapping to that address.
+func LookupAddr(addr string) (name []string, err os.Error) {
+	arpa, err := reverseaddr(addr)
+	if err != nil {
+		return
+	}
+	lines, err := queryDNS(arpa, "ptr")
+	if err != nil {
+		return
+	}
+	for _, line := range lines {
+		f := getFields(line)
+		if len(f) < 3 {
+			continue
+		}
+		name = append(name, f[2])
+	}
+	return
+}
diff --git a/src/pkg/net/parse_test.go b/src/pkg/net/parse_test.go
index 226f354d3..8d51eba18 100644
--- a/src/pkg/net/parse_test.go
+++ b/src/pkg/net/parse_test.go
@@ -12,8 +12,8 @@ import (
 )
 
 func TestReadLine(t *testing.T) {
-	// /etc/services file does not exist on windows.
-	if runtime.GOOS == "windows" {
+	// /etc/services file does not exist on windows and Plan 9.
+	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
 		return
 	}
 	filename := "/etc/services" // a nice big file
diff --git a/src/pkg/net/server_test.go b/src/pkg/net/server_test.go
index 36780d789..7d7f7fc01 100644
--- a/src/pkg/net/server_test.go
+++ b/src/pkg/net/server_test.go
@@ -146,8 +146,8 @@ func TestTCPServer(t *testing.T) {
 }
 
 func TestUnixServer(t *testing.T) {
-	// "unix" sockets are not supported on windows.
-	if runtime.GOOS == "windows" {
+	// "unix" sockets are not supported on windows and Plan 9.
+	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
 		return
 	}
 	os.Remove("/tmp/gotest.net")
@@ -225,8 +225,8 @@ func TestUDPServer(t *testing.T) {
 }
 
 func TestUnixDatagramServer(t *testing.T) {
-	// "unix" sockets are not supported on windows.
-	if runtime.GOOS == "windows" {
+	// "unix" sockets are not supported on windows and Plan 9.
+	if runtime.GOOS == "windows" || runtime.GOOS == "plan9" {
 		return
 	}
 	for _, isEmpty := range []bool{false} {
diff --git a/src/pkg/net/tcpsock.go b/src/pkg/net/tcpsock.go
index 9ee6c14f7..f5c0a2781 100644
--- a/src/pkg/net/tcpsock.go
+++ b/src/pkg/net/tcpsock.go
@@ -7,21 +7,9 @@
 package net
 
 import (
-	"io"
 	"os"
-	"syscall"
 )
 
-func sockaddrToTCP(sa syscall.Sockaddr) Addr {
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		return &TCPAddr{sa.Addr[0:], sa.Port}
-	case *syscall.SockaddrInet6:
-		return &TCPAddr{sa.Addr[0:], sa.Port}
-	}
-	return nil
-}
-
 // TCPAddr represents the address of a TCP end point.
 type TCPAddr struct {
 	IP   IP
@@ -38,27 +26,6 @@ func (a *TCPAddr) String() string {
 	return JoinHostPort(a.IP.String(), itoa(a.Port))
 }
 
-func (a *TCPAddr) family() int {
-	if a == nil || len(a.IP) <= 4 {
-		return syscall.AF_INET
-	}
-	if a.IP.To4() != nil {
-		return syscall.AF_INET
-	}
-	return syscall.AF_INET6
-}
-
-func (a *TCPAddr) sockaddr(family int) (syscall.Sockaddr, os.Error) {
-	return ipToSockaddr(family, a.IP, a.Port)
-}
-
-func (a *TCPAddr) toAddr() sockaddr {
-	if a == nil { // nil *TCPAddr
-		return nil // nil interface
-	}
-	return a
-}
-
 // ResolveTCPAddr parses addr as a TCP address of the form
 // host:port and resolves domain names or port names to
 // numeric addresses on the network net, which must be "tcp",
@@ -71,234 +38,3 @@ func ResolveTCPAddr(net, addr string) (*TCPAddr, os.Error) {
 	}
 	return &TCPAddr{ip, port}, nil
 }
-
-// TCPConn is an implementation of the Conn interface
-// for TCP network connections.
-type TCPConn struct {
-	fd *netFD
-}
-
-func newTCPConn(fd *netFD) *TCPConn {
-	c := &TCPConn{fd}
-	c.SetNoDelay(true)
-	return c
-}
-
-func (c *TCPConn) ok() bool { return c != nil && c.fd != nil }
-
-// Implementation of the Conn interface - see Conn for documentation.
-
-// Read implements the net.Conn Read method.
-func (c *TCPConn) Read(b []byte) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	return c.fd.Read(b)
-}
-
-// ReadFrom implements the io.ReaderFrom ReadFrom method.
-func (c *TCPConn) ReadFrom(r io.Reader) (int64, os.Error) {
-	if n, err, handled := sendFile(c.fd, r); handled {
-		return n, err
-	}
-	return genericReadFrom(c, r)
-}
-
-// Write implements the net.Conn Write method.
-func (c *TCPConn) Write(b []byte) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	return c.fd.Write(b)
-}
-
-// Close closes the TCP connection.
-func (c *TCPConn) Close() os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	err := c.fd.Close()
-	c.fd = nil
-	return err
-}
-
-// LocalAddr returns the local network address, a *TCPAddr.
-func (c *TCPConn) LocalAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.laddr
-}
-
-// RemoteAddr returns the remote network address, a *TCPAddr.
-func (c *TCPConn) RemoteAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.raddr
-}
-
-// SetTimeout implements the net.Conn SetTimeout method.
-func (c *TCPConn) SetTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setTimeout(c.fd, nsec)
-}
-
-// SetReadTimeout implements the net.Conn SetReadTimeout method.
-func (c *TCPConn) SetReadTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadTimeout(c.fd, nsec)
-}
-
-// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
-func (c *TCPConn) SetWriteTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteTimeout(c.fd, nsec)
-}
-
-// SetReadBuffer sets the size of the operating system's
-// receive buffer associated with the connection.
-func (c *TCPConn) SetReadBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadBuffer(c.fd, bytes)
-}
-
-// SetWriteBuffer sets the size of the operating system's
-// transmit buffer associated with the connection.
-func (c *TCPConn) SetWriteBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteBuffer(c.fd, bytes)
-}
-
-// SetLinger sets the behavior of Close() on a connection
-// which still has data waiting to be sent or to be acknowledged.
-//
-// If sec < 0 (the default), Close returns immediately and
-// the operating system finishes sending the data in the background.
-//
-// If sec == 0, Close returns immediately and the operating system
-// discards any unsent or unacknowledged data.
-//
-// If sec > 0, Close blocks for at most sec seconds waiting for
-// data to be sent and acknowledged.
-func (c *TCPConn) SetLinger(sec int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setLinger(c.fd, sec)
-}
-
-// SetKeepAlive sets whether the operating system should send
-// keepalive messages on the connection.
-func (c *TCPConn) SetKeepAlive(keepalive bool) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setKeepAlive(c.fd, keepalive)
-}
-
-// SetNoDelay controls whether the operating system should delay
-// packet transmission in hopes of sending fewer packets
-// (Nagle's algorithm).  The default is true (no delay), meaning
-// that data is sent as soon as possible after a Write.
-func (c *TCPConn) SetNoDelay(noDelay bool) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setNoDelay(c.fd, noDelay)
-}
-
-// File returns a copy of the underlying os.File, set to blocking mode.
-// It is the caller's responsibility to close f when finished.
-// Closing c does not affect f, and closing f does not affect c.
-func (c *TCPConn) File() (f *os.File, err os.Error) { return c.fd.dup() }
-
-// DialTCP connects to the remote address raddr on the network net,
-// which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is used
-// as the local address for the connection.
-func DialTCP(net string, laddr, raddr *TCPAddr) (c *TCPConn, err os.Error) {
-	if raddr == nil {
-		return nil, &OpError{"dial", "tcp", nil, errMissingAddress}
-	}
-	fd, e := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_STREAM, 0, "dial", sockaddrToTCP)
-	if e != nil {
-		return nil, e
-	}
-	return newTCPConn(fd), nil
-}
-
-// TCPListener is a TCP network listener.
-// Clients should typically use variables of type Listener
-// instead of assuming TCP.
-type TCPListener struct {
-	fd *netFD
-}
-
-// ListenTCP announces on the TCP address laddr and returns a TCP listener.
-// Net must be "tcp", "tcp4", or "tcp6".
-// If laddr has a port of 0, it means to listen on some available port.
-// The caller can use l.Addr() to retrieve the chosen address.
-func ListenTCP(net string, laddr *TCPAddr) (l *TCPListener, err os.Error) {
-	fd, err := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_STREAM, 0, "listen", sockaddrToTCP)
-	if err != nil {
-		return nil, err
-	}
-	errno := syscall.Listen(fd.sysfd, listenBacklog())
-	if errno != 0 {
-		closesocket(fd.sysfd)
-		return nil, &OpError{"listen", "tcp", laddr, os.Errno(errno)}
-	}
-	l = new(TCPListener)
-	l.fd = fd
-	return l, nil
-}
-
-// AcceptTCP accepts the next incoming call and returns the new connection
-// and the remote address.
-func (l *TCPListener) AcceptTCP() (c *TCPConn, err os.Error) {
-	if l == nil || l.fd == nil || l.fd.sysfd < 0 {
-		return nil, os.EINVAL
-	}
-	fd, err := l.fd.accept(sockaddrToTCP)
-	if err != nil {
-		return nil, err
-	}
-	return newTCPConn(fd), nil
-}
-
-// Accept implements the Accept method in the Listener interface;
-// it waits for the next call and returns a generic Conn.
-func (l *TCPListener) Accept() (c Conn, err os.Error) {
-	c1, err := l.AcceptTCP()
-	if err != nil {
-		return nil, err
-	}
-	return c1, nil
-}
-
-// Close stops listening on the TCP address.
-// Already Accepted connections are not closed.
-func (l *TCPListener) Close() os.Error {
-	if l == nil || l.fd == nil {
-		return os.EINVAL
-	}
-	return l.fd.Close()
-}
-
-// Addr returns the listener's network address, a *TCPAddr.
-func (l *TCPListener) Addr() Addr { return l.fd.laddr }
-
-// File returns a copy of the underlying os.File, set to blocking mode.
-// It is the caller's responsibility to close f when finished.
-// Closing c does not affect f, and closing f does not affect c.
-func (l *TCPListener) File() (f *os.File, err os.Error) { return l.fd.dup() }
diff --git a/src/pkg/net/tcpsock_plan9.go b/src/pkg/net/tcpsock_plan9.go
new file mode 100644
index 000000000..f4f6e9fee
--- /dev/null
+++ b/src/pkg/net/tcpsock_plan9.go
@@ -0,0 +1,63 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// TCP for Plan 9
+
+package net
+
+import (
+	"os"
+)
+
+// TCPConn is an implementation of the Conn interface
+// for TCP network connections.
+type TCPConn struct {
+	plan9Conn
+}
+
+// DialTCP connects to the remote address raddr on the network net,
+// which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is used
+// as the local address for the connection.
+func DialTCP(net string, laddr, raddr *TCPAddr) (c *TCPConn, err os.Error) {
+	switch net {
+	case "tcp", "tcp4", "tcp6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if raddr == nil {
+		return nil, &OpError{"dial", "tcp", nil, errMissingAddress}
+	}
+	c1, err := dialPlan9(net, laddr, raddr)
+	if err != nil {
+		return
+	}
+	return &TCPConn{*c1}, nil
+}
+
+// TCPListener is a TCP network listener.
+// Clients should typically use variables of type Listener
+// instead of assuming TCP.
+type TCPListener struct {
+	plan9Listener
+}
+
+// ListenTCP announces on the TCP address laddr and returns a TCP listener.
+// Net must be "tcp", "tcp4", or "tcp6".
+// If laddr has a port of 0, it means to listen on some available port.
+// The caller can use l.Addr() to retrieve the chosen address.
+func ListenTCP(net string, laddr *TCPAddr) (l *TCPListener, err os.Error) {
+	switch net {
+	case "tcp", "tcp4", "tcp6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if laddr == nil {
+		return nil, &OpError{"listen", "tcp", nil, errMissingAddress}
+	}
+	l1, err := listenPlan9(net, laddr)
+	if err != nil {
+		return
+	}
+	return &TCPListener{*l1}, nil
+}
diff --git a/src/pkg/net/tcpsock_posix.go b/src/pkg/net/tcpsock_posix.go
new file mode 100644
index 000000000..5560301b4
--- /dev/null
+++ b/src/pkg/net/tcpsock_posix.go
@@ -0,0 +1,283 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// TCP sockets
+
+package net
+
+import (
+	"io"
+	"os"
+	"syscall"
+)
+
+func sockaddrToTCP(sa syscall.Sockaddr) Addr {
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		return &TCPAddr{sa.Addr[0:], sa.Port}
+	case *syscall.SockaddrInet6:
+		return &TCPAddr{sa.Addr[0:], sa.Port}
+	}
+	return nil
+}
+
+func (a *TCPAddr) family() int {
+	if a == nil || len(a.IP) <= 4 {
+		return syscall.AF_INET
+	}
+	if a.IP.To4() != nil {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+func (a *TCPAddr) sockaddr(family int) (syscall.Sockaddr, os.Error) {
+	return ipToSockaddr(family, a.IP, a.Port)
+}
+
+func (a *TCPAddr) toAddr() sockaddr {
+	if a == nil { // nil *TCPAddr
+		return nil // nil interface
+	}
+	return a
+}
+
+// TCPConn is an implementation of the Conn interface
+// for TCP network connections.
+type TCPConn struct {
+	fd *netFD
+}
+
+func newTCPConn(fd *netFD) *TCPConn {
+	c := &TCPConn{fd}
+	c.SetNoDelay(true)
+	return c
+}
+
+func (c *TCPConn) ok() bool { return c != nil && c.fd != nil }
+
+// Implementation of the Conn interface - see Conn for documentation.
+
+// Read implements the net.Conn Read method.
+func (c *TCPConn) Read(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	return c.fd.Read(b)
+}
+
+// ReadFrom implements the io.ReaderFrom ReadFrom method.
+func (c *TCPConn) ReadFrom(r io.Reader) (int64, os.Error) {
+	if n, err, handled := sendFile(c.fd, r); handled {
+		return n, err
+	}
+	return genericReadFrom(c, r)
+}
+
+// Write implements the net.Conn Write method.
+func (c *TCPConn) Write(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	return c.fd.Write(b)
+}
+
+// Close closes the TCP connection.
+func (c *TCPConn) Close() os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	err := c.fd.Close()
+	c.fd = nil
+	return err
+}
+
+// LocalAddr returns the local network address, a *TCPAddr.
+func (c *TCPConn) LocalAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.laddr
+}
+
+// RemoteAddr returns the remote network address, a *TCPAddr.
+func (c *TCPConn) RemoteAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.raddr
+}
+
+// SetTimeout implements the net.Conn SetTimeout method.
+func (c *TCPConn) SetTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setTimeout(c.fd, nsec)
+}
+
+// SetReadTimeout implements the net.Conn SetReadTimeout method.
+func (c *TCPConn) SetReadTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadTimeout(c.fd, nsec)
+}
+
+// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
+func (c *TCPConn) SetWriteTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteTimeout(c.fd, nsec)
+}
+
+// SetReadBuffer sets the size of the operating system's
+// receive buffer associated with the connection.
+func (c *TCPConn) SetReadBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadBuffer(c.fd, bytes)
+}
+
+// SetWriteBuffer sets the size of the operating system's
+// transmit buffer associated with the connection.
+func (c *TCPConn) SetWriteBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteBuffer(c.fd, bytes)
+}
+
+// SetLinger sets the behavior of Close() on a connection
+// which still has data waiting to be sent or to be acknowledged.
+//
+// If sec < 0 (the default), Close returns immediately and
+// the operating system finishes sending the data in the background.
+//
+// If sec == 0, Close returns immediately and the operating system
+// discards any unsent or unacknowledged data.
+//
+// If sec > 0, Close blocks for at most sec seconds waiting for
+// data to be sent and acknowledged.
+func (c *TCPConn) SetLinger(sec int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setLinger(c.fd, sec)
+}
+
+// SetKeepAlive sets whether the operating system should send
+// keepalive messages on the connection.
+func (c *TCPConn) SetKeepAlive(keepalive bool) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setKeepAlive(c.fd, keepalive)
+}
+
+// SetNoDelay controls whether the operating system should delay
+// packet transmission in hopes of sending fewer packets
+// (Nagle's algorithm).  The default is true (no delay), meaning
+// that data is sent as soon as possible after a Write.
+func (c *TCPConn) SetNoDelay(noDelay bool) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setNoDelay(c.fd, noDelay)
+}
+
+// File returns a copy of the underlying os.File, set to blocking mode.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+func (c *TCPConn) File() (f *os.File, err os.Error) { return c.fd.dup() }
+
+// DialTCP connects to the remote address raddr on the network net,
+// which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is used
+// as the local address for the connection.
+func DialTCP(net string, laddr, raddr *TCPAddr) (c *TCPConn, err os.Error) {
+	if raddr == nil {
+		return nil, &OpError{"dial", "tcp", nil, errMissingAddress}
+	}
+	fd, e := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_STREAM, 0, "dial", sockaddrToTCP)
+	if e != nil {
+		return nil, e
+	}
+	return newTCPConn(fd), nil
+}
+
+// TCPListener is a TCP network listener.
+// Clients should typically use variables of type Listener
+// instead of assuming TCP.
+type TCPListener struct {
+	fd *netFD
+}
+
+// ListenTCP announces on the TCP address laddr and returns a TCP listener.
+// Net must be "tcp", "tcp4", or "tcp6".
+// If laddr has a port of 0, it means to listen on some available port.
+// The caller can use l.Addr() to retrieve the chosen address.
+func ListenTCP(net string, laddr *TCPAddr) (l *TCPListener, err os.Error) {
+	fd, err := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_STREAM, 0, "listen", sockaddrToTCP)
+	if err != nil {
+		return nil, err
+	}
+	errno := syscall.Listen(fd.sysfd, listenBacklog())
+	if errno != 0 {
+		closesocket(fd.sysfd)
+		return nil, &OpError{"listen", "tcp", laddr, os.Errno(errno)}
+	}
+	l = new(TCPListener)
+	l.fd = fd
+	return l, nil
+}
+
+// AcceptTCP accepts the next incoming call and returns the new connection
+// and the remote address.
+func (l *TCPListener) AcceptTCP() (c *TCPConn, err os.Error) {
+	if l == nil || l.fd == nil || l.fd.sysfd < 0 {
+		return nil, os.EINVAL
+	}
+	fd, err := l.fd.accept(sockaddrToTCP)
+	if err != nil {
+		return nil, err
+	}
+	return newTCPConn(fd), nil
+}
+
+// Accept implements the Accept method in the Listener interface;
+// it waits for the next call and returns a generic Conn.
+func (l *TCPListener) Accept() (c Conn, err os.Error) {
+	c1, err := l.AcceptTCP()
+	if err != nil {
+		return nil, err
+	}
+	return c1, nil
+}
+
+// Close stops listening on the TCP address.
+// Already Accepted connections are not closed.
+func (l *TCPListener) Close() os.Error {
+	if l == nil || l.fd == nil {
+		return os.EINVAL
+	}
+	return l.fd.Close()
+}
+
+// Addr returns the listener's network address, a *TCPAddr.
+func (l *TCPListener) Addr() Addr { return l.fd.laddr }
+
+// SetTimeout sets the deadline associated with the listener
+func (l *TCPListener) SetTimeout(nsec int64) os.Error {
+	if l == nil || l.fd == nil {
+		return os.EINVAL
+	}
+	return setTimeout(l.fd, nsec)
+}
+
+// File returns a copy of the underlying os.File, set to blocking mode.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+func (l *TCPListener) File() (f *os.File, err os.Error) { return l.fd.dup() }
diff --git a/src/pkg/net/udpsock.go b/src/pkg/net/udpsock.go
index 94e249d62..3dfa71675 100644
--- a/src/pkg/net/udpsock.go
+++ b/src/pkg/net/udpsock.go
@@ -8,19 +8,8 @@ package net
 
 import (
 	"os"
-	"syscall"
 )
 
-func sockaddrToUDP(sa syscall.Sockaddr) Addr {
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		return &UDPAddr{sa.Addr[0:], sa.Port}
-	case *syscall.SockaddrInet6:
-		return &UDPAddr{sa.Addr[0:], sa.Port}
-	}
-	return nil
-}
-
 // UDPAddr represents the address of a UDP end point.
 type UDPAddr struct {
 	IP   IP
@@ -37,27 +26,6 @@ func (a *UDPAddr) String() string {
 	return JoinHostPort(a.IP.String(), itoa(a.Port))
 }
 
-func (a *UDPAddr) family() int {
-	if a == nil || len(a.IP) <= 4 {
-		return syscall.AF_INET
-	}
-	if a.IP.To4() != nil {
-		return syscall.AF_INET
-	}
-	return syscall.AF_INET6
-}
-
-func (a *UDPAddr) sockaddr(family int) (syscall.Sockaddr, os.Error) {
-	return ipToSockaddr(family, a.IP, a.Port)
-}
-
-func (a *UDPAddr) toAddr() sockaddr {
-	if a == nil { // nil *UDPAddr
-		return nil // nil interface
-	}
-	return a
-}
-
 // ResolveUDPAddr parses addr as a UDP address of the form
 // host:port and resolves domain names or port names to
 // numeric addresses on the network net, which must be "udp",
@@ -70,254 +38,3 @@ func ResolveUDPAddr(net, addr string) (*UDPAddr, os.Error) {
 	}
 	return &UDPAddr{ip, port}, nil
 }
-
-// UDPConn is the implementation of the Conn and PacketConn
-// interfaces for UDP network connections.
-type UDPConn struct {
-	fd *netFD
-}
-
-func newUDPConn(fd *netFD) *UDPConn { return &UDPConn{fd} }
-
-func (c *UDPConn) ok() bool { return c != nil && c.fd != nil }
-
-// Implementation of the Conn interface - see Conn for documentation.
-
-// Read implements the net.Conn Read method.
-func (c *UDPConn) Read(b []byte) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	return c.fd.Read(b)
-}
-
-// Write implements the net.Conn Write method.
-func (c *UDPConn) Write(b []byte) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	return c.fd.Write(b)
-}
-
-// Close closes the UDP connection.
-func (c *UDPConn) Close() os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	err := c.fd.Close()
-	c.fd = nil
-	return err
-}
-
-// LocalAddr returns the local network address.
-func (c *UDPConn) LocalAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.laddr
-}
-
-// RemoteAddr returns the remote network address, a *UDPAddr.
-func (c *UDPConn) RemoteAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.raddr
-}
-
-// SetTimeout implements the net.Conn SetTimeout method.
-func (c *UDPConn) SetTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setTimeout(c.fd, nsec)
-}
-
-// SetReadTimeout implements the net.Conn SetReadTimeout method.
-func (c *UDPConn) SetReadTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadTimeout(c.fd, nsec)
-}
-
-// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
-func (c *UDPConn) SetWriteTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteTimeout(c.fd, nsec)
-}
-
-// SetReadBuffer sets the size of the operating system's
-// receive buffer associated with the connection.
-func (c *UDPConn) SetReadBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadBuffer(c.fd, bytes)
-}
-
-// SetWriteBuffer sets the size of the operating system's
-// transmit buffer associated with the connection.
-func (c *UDPConn) SetWriteBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteBuffer(c.fd, bytes)
-}
-
-// UDP-specific methods.
-
-// ReadFromUDP reads a UDP packet from c, copying the payload into b.
-// It returns the number of bytes copied into b and the return address
-// that was on the packet.
-//
-// ReadFromUDP can be made to time out and return an error with Timeout() == true
-// after a fixed time limit; see SetTimeout and SetReadTimeout.
-func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err os.Error) {
-	if !c.ok() {
-		return 0, nil, os.EINVAL
-	}
-	n, sa, err := c.fd.ReadFrom(b)
-	switch sa := sa.(type) {
-	case *syscall.SockaddrInet4:
-		addr = &UDPAddr{sa.Addr[0:], sa.Port}
-	case *syscall.SockaddrInet6:
-		addr = &UDPAddr{sa.Addr[0:], sa.Port}
-	}
-	return
-}
-
-// ReadFrom implements the net.PacketConn ReadFrom method.
-func (c *UDPConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
-	if !c.ok() {
-		return 0, nil, os.EINVAL
-	}
-	n, uaddr, err := c.ReadFromUDP(b)
-	return n, uaddr.toAddr(), err
-}
-
-// WriteToUDP writes a UDP packet to addr via c, copying the payload from b.
-//
-// WriteToUDP can be made to time out and return
-// an error with Timeout() == true after a fixed time limit;
-// see SetTimeout and SetWriteTimeout.
-// On packet-oriented connections, write timeouts are rare.
-func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	sa, err1 := addr.sockaddr(c.fd.family)
-	if err1 != nil {
-		return 0, &OpError{Op: "write", Net: "udp", Addr: addr, Error: err1}
-	}
-	return c.fd.WriteTo(b, sa)
-}
-
-// WriteTo implements the net.PacketConn WriteTo method.
-func (c *UDPConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	a, ok := addr.(*UDPAddr)
-	if !ok {
-		return 0, &OpError{"writeto", "udp", addr, os.EINVAL}
-	}
-	return c.WriteToUDP(b, a)
-}
-
-// DialUDP connects to the remote address raddr on the network net,
-// which must be "udp", "udp4", or "udp6".  If laddr is not nil, it is used
-// as the local address for the connection.
-func DialUDP(net string, laddr, raddr *UDPAddr) (c *UDPConn, err os.Error) {
-	switch net {
-	case "udp", "udp4", "udp6":
-	default:
-		return nil, UnknownNetworkError(net)
-	}
-	if raddr == nil {
-		return nil, &OpError{"dial", "udp", nil, errMissingAddress}
-	}
-	fd, e := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_DGRAM, 0, "dial", sockaddrToUDP)
-	if e != nil {
-		return nil, e
-	}
-	return newUDPConn(fd), nil
-}
-
-// ListenUDP listens for incoming UDP packets addressed to the
-// local address laddr.  The returned connection c's ReadFrom
-// and WriteTo methods can be used to receive and send UDP
-// packets with per-packet addressing.
-func ListenUDP(net string, laddr *UDPAddr) (c *UDPConn, err os.Error) {
-	switch net {
-	case "udp", "udp4", "udp6":
-	default:
-		return nil, UnknownNetworkError(net)
-	}
-	if laddr == nil {
-		return nil, &OpError{"listen", "udp", nil, errMissingAddress}
-	}
-	fd, e := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_DGRAM, 0, "dial", sockaddrToUDP)
-	if e != nil {
-		return nil, e
-	}
-	return newUDPConn(fd), nil
-}
-
-// BindToDevice binds a UDPConn to a network interface.
-func (c *UDPConn) BindToDevice(device string) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	c.fd.incref()
-	defer c.fd.decref()
-	return os.NewSyscallError("setsockopt", syscall.BindToDevice(c.fd.sysfd, device))
-}
-
-// File returns a copy of the underlying os.File, set to blocking mode.
-// It is the caller's responsibility to close f when finished.
-// Closing c does not affect f, and closing f does not affect c.
-func (c *UDPConn) File() (f *os.File, err os.Error) { return c.fd.dup() }
-
-var errInvalidMulticast = os.NewError("invalid IPv4 multicast address")
-
-// JoinGroup joins the IPv4 multicast group named by addr.
-// The UDPConn must use the "udp4" network.
-func (c *UDPConn) JoinGroup(addr IP) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	ip := addr.To4()
-	if ip == nil {
-		return &OpError{"joingroup", "udp", &IPAddr{ip}, errInvalidMulticast}
-	}
-	mreq := &syscall.IPMreq{
-		Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]},
-	}
-	err := os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreq(c.fd.sysfd, syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq))
-	if err != nil {
-		return &OpError{"joingroup", "udp", &IPAddr{ip}, err}
-	}
-	return nil
-}
-
-// LeaveGroup exits the IPv4 multicast group named by addr.
-func (c *UDPConn) LeaveGroup(addr IP) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	ip := addr.To4()
-	if ip == nil {
-		return &OpError{"leavegroup", "udp", &IPAddr{ip}, errInvalidMulticast}
-	}
-	mreq := &syscall.IPMreq{
-		Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]},
-	}
-	err := os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreq(c.fd.sysfd, syscall.IPPROTO_IP, syscall.IP_DROP_MEMBERSHIP, mreq))
-	if err != nil {
-		return &OpError{"leavegroup", "udp", &IPAddr{ip}, err}
-	}
-	return nil
-}
diff --git a/src/pkg/net/udpsock_plan9.go b/src/pkg/net/udpsock_plan9.go
new file mode 100644
index 000000000..bb7196041
--- /dev/null
+++ b/src/pkg/net/udpsock_plan9.go
@@ -0,0 +1,187 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// UDP for Plan 9
+
+package net
+
+import (
+	"os"
+)
+
+// UDPConn is the implementation of the Conn and PacketConn
+// interfaces for UDP network connections.
+type UDPConn struct {
+	plan9Conn
+}
+
+// UDP-specific methods.
+
+// ReadFromUDP reads a UDP packet from c, copying the payload into b.
+// It returns the number of bytes copied into b and the return address
+// that was on the packet.
+//
+// ReadFromUDP can be made to time out and return an error with Timeout() == true
+// after a fixed time limit; see SetTimeout and SetReadTimeout.
+func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	if c.data == nil {
+		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
+		if err != nil {
+			return 0, nil, err
+		}
+	}
+	buf := make([]byte, udpHeaderSize+len(b))
+	m, err := c.data.Read(buf)
+	if err != nil {
+		return
+	}
+	if m < udpHeaderSize {
+		return 0, nil, os.NewError("short read reading UDP header")
+	}
+	buf = buf[:m]
+
+	h, buf := unmarshalUDPHeader(buf)
+	n = copy(b, buf)
+	return n, &UDPAddr{h.raddr, int(h.rport)}, nil
+}
+
+// ReadFrom implements the net.PacketConn ReadFrom method.
+func (c *UDPConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	return c.ReadFromUDP(b)
+}
+
+// WriteToUDP writes a UDP packet to addr via c, copying the payload from b.
+//
+// WriteToUDP can be made to time out and return
+// an error with Timeout() == true after a fixed time limit;
+// see SetTimeout and SetWriteTimeout.
+// On packet-oriented connections, write timeouts are rare.
+func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	if c.data == nil {
+		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
+		if err != nil {
+			return 0, err
+		}
+	}
+	h := new(udpHeader)
+	h.raddr = addr.IP.To16()
+	h.laddr = c.laddr.(*UDPAddr).IP.To16()
+	h.ifcaddr = IPv6zero // ignored (receive only)
+	h.rport = uint16(addr.Port)
+	h.lport = uint16(c.laddr.(*UDPAddr).Port)
+
+	buf := make([]byte, udpHeaderSize+len(b))
+	i := copy(buf, h.Bytes())
+	copy(buf[i:], b)
+	return c.data.Write(buf)
+}
+
+// WriteTo implements the net.PacketConn WriteTo method.
+func (c *UDPConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	a, ok := addr.(*UDPAddr)
+	if !ok {
+		return 0, &OpError{"writeto", "udp", addr, os.EINVAL}
+	}
+	return c.WriteToUDP(b, a)
+}
+
+// DialUDP connects to the remote address raddr on the network net,
+// which must be "udp", "udp4", or "udp6".  If laddr is not nil, it is used
+// as the local address for the connection.
+func DialUDP(net string, laddr, raddr *UDPAddr) (c *UDPConn, err os.Error) {
+	switch net {
+	case "udp", "udp4", "udp6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if raddr == nil {
+		return nil, &OpError{"dial", "udp", nil, errMissingAddress}
+	}
+	c1, err := dialPlan9(net, laddr, raddr)
+	if err != nil {
+		return
+	}
+	return &UDPConn{*c1}, nil
+}
+
+const udpHeaderSize = 16*3 + 2*2
+
+type udpHeader struct {
+	raddr, laddr, ifcaddr IP
+	rport, lport          uint16
+}
+
+func (h *udpHeader) Bytes() []byte {
+	b := make([]byte, udpHeaderSize)
+	i := 0
+	i += copy(b[i:i+16], h.raddr)
+	i += copy(b[i:i+16], h.laddr)
+	i += copy(b[i:i+16], h.ifcaddr)
+	b[i], b[i+1], i = byte(h.rport>>8), byte(h.rport), i+2
+	b[i], b[i+1], i = byte(h.lport>>8), byte(h.lport), i+2
+	return b
+}
+
+func unmarshalUDPHeader(b []byte) (*udpHeader, []byte) {
+	h := new(udpHeader)
+	h.raddr, b = IP(b[:16]), b[16:]
+	h.laddr, b = IP(b[:16]), b[16:]
+	h.ifcaddr, b = IP(b[:16]), b[16:]
+	h.rport, b = uint16(b[0])<<8|uint16(b[1]), b[2:]
+	h.lport, b = uint16(b[0])<<8|uint16(b[1]), b[2:]
+	return h, b
+}
+
+// ListenUDP listens for incoming UDP packets addressed to the
+// local address laddr.  The returned connection c's ReadFrom
+// and WriteTo methods can be used to receive and send UDP
+// packets with per-packet addressing.
+func ListenUDP(net string, laddr *UDPAddr) (c *UDPConn, err os.Error) {
+	switch net {
+	case "udp", "udp4", "udp6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if laddr == nil {
+		return nil, &OpError{"listen", "udp", nil, errMissingAddress}
+	}
+	l, err := listenPlan9(net, laddr)
+	if err != nil {
+		return
+	}
+	_, err = l.ctl.WriteString("headers")
+	if err != nil {
+		return
+	}
+	return &UDPConn{*l.plan9Conn()}, nil
+}
+
+// JoinGroup joins the IPv4 multicast group named by addr.
+// The UDPConn must use the "udp4" network.
+func (c *UDPConn) JoinGroup(addr IP) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return os.EPLAN9
+}
+
+// LeaveGroup exits the IPv4 multicast group named by addr.
+func (c *UDPConn) LeaveGroup(addr IP) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return os.EPLAN9
+}
diff --git a/src/pkg/net/udpsock_posix.go b/src/pkg/net/udpsock_posix.go
new file mode 100644
index 000000000..d4ea056f3
--- /dev/null
+++ b/src/pkg/net/udpsock_posix.go
@@ -0,0 +1,294 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// UDP sockets
+
+package net
+
+import (
+	"os"
+	"syscall"
+)
+
+func sockaddrToUDP(sa syscall.Sockaddr) Addr {
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		return &UDPAddr{sa.Addr[0:], sa.Port}
+	case *syscall.SockaddrInet6:
+		return &UDPAddr{sa.Addr[0:], sa.Port}
+	}
+	return nil
+}
+
+func (a *UDPAddr) family() int {
+	if a == nil || len(a.IP) <= 4 {
+		return syscall.AF_INET
+	}
+	if a.IP.To4() != nil {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+func (a *UDPAddr) sockaddr(family int) (syscall.Sockaddr, os.Error) {
+	return ipToSockaddr(family, a.IP, a.Port)
+}
+
+func (a *UDPAddr) toAddr() sockaddr {
+	if a == nil { // nil *UDPAddr
+		return nil // nil interface
+	}
+	return a
+}
+
+// UDPConn is the implementation of the Conn and PacketConn
+// interfaces for UDP network connections.
+type UDPConn struct {
+	fd *netFD
+}
+
+func newUDPConn(fd *netFD) *UDPConn { return &UDPConn{fd} }
+
+func (c *UDPConn) ok() bool { return c != nil && c.fd != nil }
+
+// Implementation of the Conn interface - see Conn for documentation.
+
+// Read implements the net.Conn Read method.
+func (c *UDPConn) Read(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	return c.fd.Read(b)
+}
+
+// Write implements the net.Conn Write method.
+func (c *UDPConn) Write(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	return c.fd.Write(b)
+}
+
+// Close closes the UDP connection.
+func (c *UDPConn) Close() os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	err := c.fd.Close()
+	c.fd = nil
+	return err
+}
+
+// LocalAddr returns the local network address.
+func (c *UDPConn) LocalAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.laddr
+}
+
+// RemoteAddr returns the remote network address, a *UDPAddr.
+func (c *UDPConn) RemoteAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.raddr
+}
+
+// SetTimeout implements the net.Conn SetTimeout method.
+func (c *UDPConn) SetTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setTimeout(c.fd, nsec)
+}
+
+// SetReadTimeout implements the net.Conn SetReadTimeout method.
+func (c *UDPConn) SetReadTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadTimeout(c.fd, nsec)
+}
+
+// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
+func (c *UDPConn) SetWriteTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteTimeout(c.fd, nsec)
+}
+
+// SetReadBuffer sets the size of the operating system's
+// receive buffer associated with the connection.
+func (c *UDPConn) SetReadBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadBuffer(c.fd, bytes)
+}
+
+// SetWriteBuffer sets the size of the operating system's
+// transmit buffer associated with the connection.
+func (c *UDPConn) SetWriteBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteBuffer(c.fd, bytes)
+}
+
+// UDP-specific methods.
+
+// ReadFromUDP reads a UDP packet from c, copying the payload into b.
+// It returns the number of bytes copied into b and the return address
+// that was on the packet.
+//
+// ReadFromUDP can be made to time out and return an error with Timeout() == true
+// after a fixed time limit; see SetTimeout and SetReadTimeout.
+func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	n, sa, err := c.fd.ReadFrom(b)
+	switch sa := sa.(type) {
+	case *syscall.SockaddrInet4:
+		addr = &UDPAddr{sa.Addr[0:], sa.Port}
+	case *syscall.SockaddrInet6:
+		addr = &UDPAddr{sa.Addr[0:], sa.Port}
+	}
+	return
+}
+
+// ReadFrom implements the net.PacketConn ReadFrom method.
+func (c *UDPConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	n, uaddr, err := c.ReadFromUDP(b)
+	return n, uaddr.toAddr(), err
+}
+
+// WriteToUDP writes a UDP packet to addr via c, copying the payload from b.
+//
+// WriteToUDP can be made to time out and return
+// an error with Timeout() == true after a fixed time limit;
+// see SetTimeout and SetWriteTimeout.
+// On packet-oriented connections, write timeouts are rare.
+func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	sa, err1 := addr.sockaddr(c.fd.family)
+	if err1 != nil {
+		return 0, &OpError{Op: "write", Net: "udp", Addr: addr, Error: err1}
+	}
+	return c.fd.WriteTo(b, sa)
+}
+
+// WriteTo implements the net.PacketConn WriteTo method.
+func (c *UDPConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	a, ok := addr.(*UDPAddr)
+	if !ok {
+		return 0, &OpError{"writeto", "udp", addr, os.EINVAL}
+	}
+	return c.WriteToUDP(b, a)
+}
+
+// DialUDP connects to the remote address raddr on the network net,
+// which must be "udp", "udp4", or "udp6".  If laddr is not nil, it is used
+// as the local address for the connection.
+func DialUDP(net string, laddr, raddr *UDPAddr) (c *UDPConn, err os.Error) {
+	switch net {
+	case "udp", "udp4", "udp6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if raddr == nil {
+		return nil, &OpError{"dial", "udp", nil, errMissingAddress}
+	}
+	fd, e := internetSocket(net, laddr.toAddr(), raddr.toAddr(), syscall.SOCK_DGRAM, 0, "dial", sockaddrToUDP)
+	if e != nil {
+		return nil, e
+	}
+	return newUDPConn(fd), nil
+}
+
+// ListenUDP listens for incoming UDP packets addressed to the
+// local address laddr.  The returned connection c's ReadFrom
+// and WriteTo methods can be used to receive and send UDP
+// packets with per-packet addressing.
+func ListenUDP(net string, laddr *UDPAddr) (c *UDPConn, err os.Error) {
+	switch net {
+	case "udp", "udp4", "udp6":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if laddr == nil {
+		return nil, &OpError{"listen", "udp", nil, errMissingAddress}
+	}
+	fd, e := internetSocket(net, laddr.toAddr(), nil, syscall.SOCK_DGRAM, 0, "dial", sockaddrToUDP)
+	if e != nil {
+		return nil, e
+	}
+	return newUDPConn(fd), nil
+}
+
+// BindToDevice binds a UDPConn to a network interface.
+func (c *UDPConn) BindToDevice(device string) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	c.fd.incref()
+	defer c.fd.decref()
+	return os.NewSyscallError("setsockopt", syscall.BindToDevice(c.fd.sysfd, device))
+}
+
+// File returns a copy of the underlying os.File, set to blocking mode.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+func (c *UDPConn) File() (f *os.File, err os.Error) { return c.fd.dup() }
+
+var errInvalidMulticast = os.NewError("invalid IPv4 multicast address")
+
+// JoinGroup joins the IPv4 multicast group named by addr.
+// The UDPConn must use the "udp4" network.
+func (c *UDPConn) JoinGroup(addr IP) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	ip := addr.To4()
+	if ip == nil {
+		return &OpError{"joingroup", "udp", &IPAddr{ip}, errInvalidMulticast}
+	}
+	mreq := &syscall.IPMreq{
+		Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]},
+	}
+	err := os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreq(c.fd.sysfd, syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq))
+	if err != nil {
+		return &OpError{"joingroup", "udp", &IPAddr{ip}, err}
+	}
+	return nil
+}
+
+// LeaveGroup exits the IPv4 multicast group named by addr.
+func (c *UDPConn) LeaveGroup(addr IP) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	ip := addr.To4()
+	if ip == nil {
+		return &OpError{"leavegroup", "udp", &IPAddr{ip}, errInvalidMulticast}
+	}
+	mreq := &syscall.IPMreq{
+		Multiaddr: [4]byte{ip[0], ip[1], ip[2], ip[3]},
+	}
+	err := os.NewSyscallError("setsockopt", syscall.SetsockoptIPMreq(c.fd.sysfd, syscall.IPPROTO_IP, syscall.IP_DROP_MEMBERSHIP, mreq))
+	if err != nil {
+		return &OpError{"leavegroup", "udp", &IPAddr{ip}, err}
+	}
+	return nil
+}
diff --git a/src/pkg/net/unixsock.go b/src/pkg/net/unixsock.go
index 8c26a7baf..d5040f9a2 100644
--- a/src/pkg/net/unixsock.go
+++ b/src/pkg/net/unixsock.go
@@ -8,109 +8,14 @@ package net
 
 import (
 	"os"
-	"syscall"
 )
 
-func unixSocket(net string, laddr, raddr *UnixAddr, mode string) (fd *netFD, err os.Error) {
-	var proto int
-	switch net {
-	default:
-		return nil, UnknownNetworkError(net)
-	case "unix":
-		proto = syscall.SOCK_STREAM
-	case "unixgram":
-		proto = syscall.SOCK_DGRAM
-	case "unixpacket":
-		proto = syscall.SOCK_SEQPACKET
-	}
-
-	var la, ra syscall.Sockaddr
-	switch mode {
-	default:
-		panic("unixSocket mode " + mode)
-
-	case "dial":
-		if laddr != nil {
-			la = &syscall.SockaddrUnix{Name: laddr.Name}
-		}
-		if raddr != nil {
-			ra = &syscall.SockaddrUnix{Name: raddr.Name}
-		} else if proto != syscall.SOCK_DGRAM || laddr == nil {
-			return nil, &OpError{Op: mode, Net: net, Error: errMissingAddress}
-		}
-
-	case "listen":
-		if laddr == nil {
-			return nil, &OpError{mode, net, nil, errMissingAddress}
-		}
-		la = &syscall.SockaddrUnix{Name: laddr.Name}
-		if raddr != nil {
-			return nil, &OpError{Op: mode, Net: net, Addr: raddr, Error: &AddrError{Error: "unexpected remote address", Addr: raddr.String()}}
-		}
-	}
-
-	f := sockaddrToUnix
-	if proto == syscall.SOCK_DGRAM {
-		f = sockaddrToUnixgram
-	} else if proto == syscall.SOCK_SEQPACKET {
-		f = sockaddrToUnixpacket
-	}
-
-	fd, oserr := socket(net, syscall.AF_UNIX, proto, 0, la, ra, f)
-	if oserr != nil {
-		goto Error
-	}
-	return fd, nil
-
-Error:
-	addr := raddr
-	if mode == "listen" {
-		addr = laddr
-	}
-	return nil, &OpError{Op: mode, Net: net, Addr: addr, Error: oserr}
-}
-
 // UnixAddr represents the address of a Unix domain socket end point.
 type UnixAddr struct {
 	Name string
 	Net  string
 }
 
-func sockaddrToUnix(sa syscall.Sockaddr) Addr {
-	if s, ok := sa.(*syscall.SockaddrUnix); ok {
-		return &UnixAddr{s.Name, "unix"}
-	}
-	return nil
-}
-
-func sockaddrToUnixgram(sa syscall.Sockaddr) Addr {
-	if s, ok := sa.(*syscall.SockaddrUnix); ok {
-		return &UnixAddr{s.Name, "unixgram"}
-	}
-	return nil
-}
-
-func sockaddrToUnixpacket(sa syscall.Sockaddr) Addr {
-	if s, ok := sa.(*syscall.SockaddrUnix); ok {
-		return &UnixAddr{s.Name, "unixpacket"}
-	}
-	return nil
-}
-
-func protoToNet(proto int) string {
-	switch proto {
-	case syscall.SOCK_STREAM:
-		return "unix"
-	case syscall.SOCK_SEQPACKET:
-		return "unixpacket"
-	case syscall.SOCK_DGRAM:
-		return "unixgram"
-	default:
-		panic("protoToNet unknown protocol")
-	}
-	return ""
-}
-
 // Network returns the address's network name, "unix" or "unixgram".
 func (a *UnixAddr) Network() string {
 	return a.Net
@@ -143,307 +48,3 @@ func ResolveUnixAddr(net, addr string) (*UnixAddr, os.Error) {
 	}
 	return &UnixAddr{addr, net}, nil
 }
-
-// UnixConn is an implementation of the Conn interface
-// for connections to Unix domain sockets.
-type UnixConn struct {
-	fd *netFD
-}
-
-func newUnixConn(fd *netFD) *UnixConn { return &UnixConn{fd} }
-
-func (c *UnixConn) ok() bool { return c != nil && c.fd != nil }
-
-// Implementation of the Conn interface - see Conn for documentation.
-
-// Read implements the net.Conn Read method.
-func (c *UnixConn) Read(b []byte) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	return c.fd.Read(b)
-}
-
-// Write implements the net.Conn Write method.
-func (c *UnixConn) Write(b []byte) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	return c.fd.Write(b)
-}
-
-// Close closes the Unix domain connection.
-func (c *UnixConn) Close() os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	err := c.fd.Close()
-	c.fd = nil
-	return err
-}
-
-// LocalAddr returns the local network address, a *UnixAddr.
-// Unlike in other protocols, LocalAddr is usually nil for dialed connections.
-func (c *UnixConn) LocalAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.laddr
-}
-
-// RemoteAddr returns the remote network address, a *UnixAddr.
-// Unlike in other protocols, RemoteAddr is usually nil for connections
-// accepted by a listener.
-func (c *UnixConn) RemoteAddr() Addr {
-	if !c.ok() {
-		return nil
-	}
-	return c.fd.raddr
-}
-
-// SetTimeout implements the net.Conn SetTimeout method.
-func (c *UnixConn) SetTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setTimeout(c.fd, nsec)
-}
-
-// SetReadTimeout implements the net.Conn SetReadTimeout method.
-func (c *UnixConn) SetReadTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadTimeout(c.fd, nsec)
-}
-
-// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
-func (c *UnixConn) SetWriteTimeout(nsec int64) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteTimeout(c.fd, nsec)
-}
-
-// SetReadBuffer sets the size of the operating system's
-// receive buffer associated with the connection.
-func (c *UnixConn) SetReadBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setReadBuffer(c.fd, bytes)
-}
-
-// SetWriteBuffer sets the size of the operating system's
-// transmit buffer associated with the connection.
-func (c *UnixConn) SetWriteBuffer(bytes int) os.Error {
-	if !c.ok() {
-		return os.EINVAL
-	}
-	return setWriteBuffer(c.fd, bytes)
-}
-
-// ReadFromUnix reads a packet from c, copying the payload into b.
-// It returns the number of bytes copied into b and the return address
-// that was on the packet.
-//
-// ReadFromUnix can be made to time out and return
-// an error with Timeout() == true after a fixed time limit;
-// see SetTimeout and SetReadTimeout.
-func (c *UnixConn) ReadFromUnix(b []byte) (n int, addr *UnixAddr, err os.Error) {
-	if !c.ok() {
-		return 0, nil, os.EINVAL
-	}
-	n, sa, err := c.fd.ReadFrom(b)
-	switch sa := sa.(type) {
-	case *syscall.SockaddrUnix:
-		addr = &UnixAddr{sa.Name, protoToNet(c.fd.proto)}
-	}
-	return
-}
-
-// ReadFrom implements the net.PacketConn ReadFrom method.
-func (c *UnixConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
-	if !c.ok() {
-		return 0, nil, os.EINVAL
-	}
-	n, uaddr, err := c.ReadFromUnix(b)
-	return n, uaddr.toAddr(), err
-}
-
-// WriteToUnix writes a packet to addr via c, copying the payload from b.
-//
-// WriteToUnix can be made to time out and return
-// an error with Timeout() == true after a fixed time limit;
-// see SetTimeout and SetWriteTimeout.
-// On packet-oriented connections, write timeouts are rare.
-func (c *UnixConn) WriteToUnix(b []byte, addr *UnixAddr) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	if addr.Net != protoToNet(c.fd.proto) {
-		return 0, os.EAFNOSUPPORT
-	}
-	sa := &syscall.SockaddrUnix{Name: addr.Name}
-	return c.fd.WriteTo(b, sa)
-}
-
-// WriteTo implements the net.PacketConn WriteTo method.
-func (c *UnixConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
-	if !c.ok() {
-		return 0, os.EINVAL
-	}
-	a, ok := addr.(*UnixAddr)
-	if !ok {
-		return 0, &OpError{"writeto", "unix", addr, os.EINVAL}
-	}
-	return c.WriteToUnix(b, a)
-}
-
-func (c *UnixConn) ReadMsgUnix(b, oob []byte) (n, oobn, flags int, addr *UnixAddr, err os.Error) {
-	if !c.ok() {
-		return 0, 0, 0, nil, os.EINVAL
-	}
-	n, oobn, flags, sa, err := c.fd.ReadMsg(b, oob)
-	switch sa := sa.(type) {
-	case *syscall.SockaddrUnix:
-		addr = &UnixAddr{sa.Name, protoToNet(c.fd.proto)}
-	}
-	return
-}
-
-func (c *UnixConn) WriteMsgUnix(b, oob []byte, addr *UnixAddr) (n, oobn int, err os.Error) {
-	if !c.ok() {
-		return 0, 0, os.EINVAL
-	}
-	if addr != nil {
-		if addr.Net != protoToNet(c.fd.proto) {
-			return 0, 0, os.EAFNOSUPPORT
-		}
-		sa := &syscall.SockaddrUnix{Name: addr.Name}
-		return c.fd.WriteMsg(b, oob, sa)
-	}
-	return c.fd.WriteMsg(b, oob, nil)
-}
-
-// File returns a copy of the underlying os.File, set to blocking mode.
-// It is the caller's responsibility to close f when finished.
-// Closing c does not affect f, and closing f does not affect c.
-func (c *UnixConn) File() (f *os.File, err os.Error) { return c.fd.dup() }
-
-// DialUnix connects to the remote address raddr on the network net,
-// which must be "unix" or "unixgram".  If laddr is not nil, it is used
-// as the local address for the connection.
-func DialUnix(net string, laddr, raddr *UnixAddr) (c *UnixConn, err os.Error) {
-	fd, e := unixSocket(net, laddr, raddr, "dial")
-	if e != nil {
-		return nil, e
-	}
-	return newUnixConn(fd), nil
-}
-
-// UnixListener is a Unix domain socket listener.
-// Clients should typically use variables of type Listener
-// instead of assuming Unix domain sockets.
-type UnixListener struct {
-	fd   *netFD
-	path string
-}
-
-// ListenUnix announces on the Unix domain socket laddr and returns a Unix listener.
-// Net must be "unix" (stream sockets).
-func ListenUnix(net string, laddr *UnixAddr) (l *UnixListener, err os.Error) {
-	if net != "unix" && net != "unixgram" && net != "unixpacket" {
-		return nil, UnknownNetworkError(net)
-	}
-	if laddr != nil {
-		laddr = &UnixAddr{laddr.Name, net} // make our own copy
-	}
-	fd, err := unixSocket(net, laddr, nil, "listen")
-	if err != nil {
-		return nil, err
-	}
-	e1 := syscall.Listen(fd.sysfd, 8) // listenBacklog());
-	if e1 != 0 {
-		closesocket(fd.sysfd)
-		return nil, &OpError{Op: "listen", Net: "unix", Addr: laddr, Error: os.Errno(e1)}
-	}
-	return &UnixListener{fd, laddr.Name}, nil
-}
-
-// AcceptUnix accepts the next incoming call and returns the new connection
-// and the remote address.
-func (l *UnixListener) AcceptUnix() (c *UnixConn, err os.Error) {
-	if l == nil || l.fd == nil {
-		return nil, os.EINVAL
-	}
-	fd, e := l.fd.accept(sockaddrToUnix)
-	if e != nil {
-		return nil, e
-	}
-	c = newUnixConn(fd)
-	return c, nil
-}
-
-// Accept implements the Accept method in the Listener interface;
-// it waits for the next call and returns a generic Conn.
-func (l *UnixListener) Accept() (c Conn, err os.Error) {
-	c1, err := l.AcceptUnix()
-	if err != nil {
-		return nil, err
-	}
-	return c1, nil
-}
-
-// Close stops listening on the Unix address.
-// Already accepted connections are not closed.
-func (l *UnixListener) Close() os.Error {
-	if l == nil || l.fd == nil {
-		return os.EINVAL
-	}
-
-	// The operating system doesn't clean up
-	// the file that announcing created, so
-	// we have to clean it up ourselves.
-	// There's a race here--we can't know for
-	// sure whether someone else has come along
-	// and replaced our socket name already--
-	// but this sequence (remove then close)
-	// is at least compatible with the auto-remove
-	// sequence in ListenUnix.  It's only non-Go
-	// programs that can mess us up.
-	if l.path[0] != '@' {
-		syscall.Unlink(l.path)
-	}
-	err := l.fd.Close()
-	l.fd = nil
-	return err
-}
-
-// Addr returns the listener's network address.
-func (l *UnixListener) Addr() Addr { return l.fd.laddr }
-
-// File returns a copy of the underlying os.File, set to blocking mode.
-// It is the caller's responsibility to close f when finished.
-// Closing c does not affect f, and closing f does not affect c.
-func (l *UnixListener) File() (f *os.File, err os.Error) { return l.fd.dup() }
-
-// ListenUnixgram listens for incoming Unix datagram packets addressed to the
-// local address laddr.  The returned connection c's ReadFrom
-// and WriteTo methods can be used to receive and send UDP
-// packets with per-packet addressing.  The network net must be "unixgram".
-func ListenUnixgram(net string, laddr *UnixAddr) (c *UDPConn, err os.Error) {
-	switch net {
-	case "unixgram":
-	default:
-		return nil, UnknownNetworkError(net)
-	}
-	if laddr == nil {
-		return nil, &OpError{"listen", "unixgram", nil, errMissingAddress}
-	}
-	fd, e := unixSocket(net, laddr, nil, "listen")
-	if e != nil {
-		return nil, e
-	}
-	return newUDPConn(fd), nil
-}
diff --git a/src/pkg/net/unixsock_plan9.go b/src/pkg/net/unixsock_plan9.go
new file mode 100644
index 000000000..7e212df8a
--- /dev/null
+++ b/src/pkg/net/unixsock_plan9.go
@@ -0,0 +1,105 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Unix domain sockets stubs for Plan 9
+
+package net
+
+import (
+	"os"
+)
+
+// UnixConn is an implementation of the Conn interface
+// for connections to Unix domain sockets.
+type UnixConn bool
+
+// Implementation of the Conn interface - see Conn for documentation.
+
+// Read implements the net.Conn Read method.
+func (c *UnixConn) Read(b []byte) (n int, err os.Error) {
+	return 0, os.EPLAN9
+}
+
+// Write implements the net.Conn Write method.
+func (c *UnixConn) Write(b []byte) (n int, err os.Error) {
+	return 0, os.EPLAN9
+}
+
+// Close closes the Unix domain connection.
+func (c *UnixConn) Close() os.Error {
+	return os.EPLAN9
+}
+
+// LocalAddr returns the local network address, a *UnixAddr.
+// Unlike in other protocols, LocalAddr is usually nil for dialed connections.
+func (c *UnixConn) LocalAddr() Addr {
+	return nil
+}
+
+// RemoteAddr returns the remote network address, a *UnixAddr.
+// Unlike in other protocols, RemoteAddr is usually nil for connections
+// accepted by a listener.
+func (c *UnixConn) RemoteAddr() Addr {
+	return nil
+}
+
+// SetTimeout implements the net.Conn SetTimeout method.
+func (c *UnixConn) SetTimeout(nsec int64) os.Error {
+	return os.EPLAN9
+}
+
+// SetReadTimeout implements the net.Conn SetReadTimeout method.
+func (c *UnixConn) SetReadTimeout(nsec int64) os.Error {
+	return os.EPLAN9
+}
+
+// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
+func (c *UnixConn) SetWriteTimeout(nsec int64) os.Error {
+	return os.EPLAN9
+}
+
+// ReadFrom implements the net.PacketConn ReadFrom method.
+func (c *UnixConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
+	err = os.EPLAN9
+	return
+}
+
+// WriteTo implements the net.PacketConn WriteTo method.
+func (c *UnixConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
+	err = os.EPLAN9
+	return
+}
+
+// DialUnix connects to the remote address raddr on the network net,
+// which must be "unix" or "unixgram".  If laddr is not nil, it is used
+// as the local address for the connection.
+func DialUnix(net string, laddr, raddr *UnixAddr) (c *UnixConn, err os.Error) {
+	return nil, os.EPLAN9
+}
+
+// UnixListener is a Unix domain socket listener.
+// Clients should typically use variables of type Listener
+// instead of assuming Unix domain sockets.
+type UnixListener bool
+
+// ListenUnix announces on the Unix domain socket laddr and returns a Unix listener.
+// Net must be "unix" (stream sockets).
+func ListenUnix(net string, laddr *UnixAddr) (l *UnixListener, err os.Error) {
+	return nil, os.EPLAN9
+}
+
+// Accept implements the Accept method in the Listener interface;
+// it waits for the next call and returns a generic Conn.
+func (l *UnixListener) Accept() (c Conn, err os.Error) {
+	return nil, os.EPLAN9
+}
+
+// Close stops listening on the Unix address.
+// Already accepted connections are not closed.
+func (l *UnixListener) Close() os.Error {
+	return os.EPLAN9
+}
+
+// Addr returns the listener's network address.
+func (l *UnixListener) Addr() Addr { return nil }
diff --git a/src/pkg/net/unixsock_posix.go b/src/pkg/net/unixsock_posix.go
new file mode 100644
index 000000000..38c6fe9eb
--- /dev/null
+++ b/src/pkg/net/unixsock_posix.go
@@ -0,0 +1,418 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Unix domain sockets
+
+package net
+
+import (
+	"os"
+	"syscall"
+)
+
+func unixSocket(net string, laddr, raddr *UnixAddr, mode string) (fd *netFD, err os.Error) {
+	var proto int
+	switch net {
+	default:
+		return nil, UnknownNetworkError(net)
+	case "unix":
+		proto = syscall.SOCK_STREAM
+	case "unixgram":
+		proto = syscall.SOCK_DGRAM
+	case "unixpacket":
+		proto = syscall.SOCK_SEQPACKET
+	}
+
+	var la, ra syscall.Sockaddr
+	switch mode {
+	default:
+		panic("unixSocket mode " + mode)
+
+	case "dial":
+		if laddr != nil {
+			la = &syscall.SockaddrUnix{Name: laddr.Name}
+		}
+		if raddr != nil {
+			ra = &syscall.SockaddrUnix{Name: raddr.Name}
+		} else if proto != syscall.SOCK_DGRAM || laddr == nil {
+			return nil, &OpError{Op: mode, Net: net, Error: errMissingAddress}
+		}
+
+	case "listen":
+		if laddr == nil {
+			return nil, &OpError{mode, net, nil, errMissingAddress}
+		}
+		la = &syscall.SockaddrUnix{Name: laddr.Name}
+		if raddr != nil {
+			return nil, &OpError{Op: mode, Net: net, Addr: raddr, Error: &AddrError{Error: "unexpected remote address", Addr: raddr.String()}}
+		}
+	}
+
+	f := sockaddrToUnix
+	if proto == syscall.SOCK_DGRAM {
+		f = sockaddrToUnixgram
+	} else if proto == syscall.SOCK_SEQPACKET {
+		f = sockaddrToUnixpacket
+	}
+
+	fd, oserr := socket(net, syscall.AF_UNIX, proto, 0, la, ra, f)
+	if oserr != nil {
+		goto Error
+	}
+	return fd, nil
+
+Error:
+	addr := raddr
+	if mode == "listen" {
+		addr = laddr
+	}
+	return nil, &OpError{Op: mode, Net: net, Addr: addr, Error: oserr}
+}
+
+func sockaddrToUnix(sa syscall.Sockaddr) Addr {
+	if s, ok := sa.(*syscall.SockaddrUnix); ok {
+		return &UnixAddr{s.Name, "unix"}
+	}
+	return nil
+}
+
+func sockaddrToUnixgram(sa syscall.Sockaddr) Addr {
+	if s, ok := sa.(*syscall.SockaddrUnix); ok {
+		return &UnixAddr{s.Name, "unixgram"}
+	}
+	return nil
+}
+
+func sockaddrToUnixpacket(sa syscall.Sockaddr) Addr {
+	if s, ok := sa.(*syscall.SockaddrUnix); ok {
+		return &UnixAddr{s.Name, "unixpacket"}
+	}
+	return nil
+}
+
+func protoToNet(proto int) string {
+	switch proto {
+	case syscall.SOCK_STREAM:
+		return "unix"
+	case syscall.SOCK_SEQPACKET:
+		return "unixpacket"
+	case syscall.SOCK_DGRAM:
+		return "unixgram"
+	default:
+		panic("protoToNet unknown protocol")
+	}
+	return ""
+}
+
+// UnixConn is an implementation of the Conn interface
+// for connections to Unix domain sockets.
+type UnixConn struct {
+	fd *netFD
+}
+
+func newUnixConn(fd *netFD) *UnixConn { return &UnixConn{fd} }
+
+func (c *UnixConn) ok() bool { return c != nil && c.fd != nil }
+
+// Implementation of the Conn interface - see Conn for documentation.
+
+// Read implements the net.Conn Read method.
+func (c *UnixConn) Read(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	return c.fd.Read(b)
+}
+
+// Write implements the net.Conn Write method.
+func (c *UnixConn) Write(b []byte) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	return c.fd.Write(b)
+}
+
+// Close closes the Unix domain connection.
+func (c *UnixConn) Close() os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	err := c.fd.Close()
+	c.fd = nil
+	return err
+}
+
+// LocalAddr returns the local network address, a *UnixAddr.
+// Unlike in other protocols, LocalAddr is usually nil for dialed connections.
+func (c *UnixConn) LocalAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.laddr
+}
+
+// RemoteAddr returns the remote network address, a *UnixAddr.
+// Unlike in other protocols, RemoteAddr is usually nil for connections
+// accepted by a listener.
+func (c *UnixConn) RemoteAddr() Addr {
+	if !c.ok() {
+		return nil
+	}
+	return c.fd.raddr
+}
+
+// SetTimeout implements the net.Conn SetTimeout method.
+func (c *UnixConn) SetTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setTimeout(c.fd, nsec)
+}
+
+// SetReadTimeout implements the net.Conn SetReadTimeout method.
+func (c *UnixConn) SetReadTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadTimeout(c.fd, nsec)
+}
+
+// SetWriteTimeout implements the net.Conn SetWriteTimeout method.
+func (c *UnixConn) SetWriteTimeout(nsec int64) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteTimeout(c.fd, nsec)
+}
+
+// SetReadBuffer sets the size of the operating system's
+// receive buffer associated with the connection.
+func (c *UnixConn) SetReadBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setReadBuffer(c.fd, bytes)
+}
+
+// SetWriteBuffer sets the size of the operating system's
+// transmit buffer associated with the connection.
+func (c *UnixConn) SetWriteBuffer(bytes int) os.Error {
+	if !c.ok() {
+		return os.EINVAL
+	}
+	return setWriteBuffer(c.fd, bytes)
+}
+
+// ReadFromUnix reads a packet from c, copying the payload into b.
+// It returns the number of bytes copied into b and the return address
+// that was on the packet.
+//
+// ReadFromUnix can be made to time out and return
+// an error with Timeout() == true after a fixed time limit;
+// see SetTimeout and SetReadTimeout.
+func (c *UnixConn) ReadFromUnix(b []byte) (n int, addr *UnixAddr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	n, sa, err := c.fd.ReadFrom(b)
+	switch sa := sa.(type) {
+	case *syscall.SockaddrUnix:
+		addr = &UnixAddr{sa.Name, protoToNet(c.fd.proto)}
+	}
+	return
+}
+
+// ReadFrom implements the net.PacketConn ReadFrom method.
+func (c *UnixConn) ReadFrom(b []byte) (n int, addr Addr, err os.Error) {
+	if !c.ok() {
+		return 0, nil, os.EINVAL
+	}
+	n, uaddr, err := c.ReadFromUnix(b)
+	return n, uaddr.toAddr(), err
+}
+
+// WriteToUnix writes a packet to addr via c, copying the payload from b.
+//
+// WriteToUnix can be made to time out and return
+// an error with Timeout() == true after a fixed time limit;
+// see SetTimeout and SetWriteTimeout.
+// On packet-oriented connections, write timeouts are rare.
+func (c *UnixConn) WriteToUnix(b []byte, addr *UnixAddr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	if addr.Net != protoToNet(c.fd.proto) {
+		return 0, os.EAFNOSUPPORT
+	}
+	sa := &syscall.SockaddrUnix{Name: addr.Name}
+	return c.fd.WriteTo(b, sa)
+}
+
+// WriteTo implements the net.PacketConn WriteTo method.
+func (c *UnixConn) WriteTo(b []byte, addr Addr) (n int, err os.Error) {
+	if !c.ok() {
+		return 0, os.EINVAL
+	}
+	a, ok := addr.(*UnixAddr)
+	if !ok {
+		return 0, &OpError{"writeto", "unix", addr, os.EINVAL}
+	}
+	return c.WriteToUnix(b, a)
+}
+
+func (c *UnixConn) ReadMsgUnix(b, oob []byte) (n, oobn, flags int, addr *UnixAddr, err os.Error) {
+	if !c.ok() {
+		return 0, 0, 0, nil, os.EINVAL
+	}
+	n, oobn, flags, sa, err := c.fd.ReadMsg(b, oob)
+	switch sa := sa.(type) {
+	case *syscall.SockaddrUnix:
+		addr = &UnixAddr{sa.Name, protoToNet(c.fd.proto)}
+	}
+	return
+}
+
+func (c *UnixConn) WriteMsgUnix(b, oob []byte, addr *UnixAddr) (n, oobn int, err os.Error) {
+	if !c.ok() {
+		return 0, 0, os.EINVAL
+	}
+	if addr != nil {
+		if addr.Net != protoToNet(c.fd.proto) {
+			return 0, 0, os.EAFNOSUPPORT
+		}
+		sa := &syscall.SockaddrUnix{Name: addr.Name}
+		return c.fd.WriteMsg(b, oob, sa)
+	}
+	return c.fd.WriteMsg(b, oob, nil)
+}
+
+// File returns a copy of the underlying os.File, set to blocking mode.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+func (c *UnixConn) File() (f *os.File, err os.Error) { return c.fd.dup() }
+
+// DialUnix connects to the remote address raddr on the network net,
+// which must be "unix" or "unixgram".  If laddr is not nil, it is used
+// as the local address for the connection.
+func DialUnix(net string, laddr, raddr *UnixAddr) (c *UnixConn, err os.Error) {
+	fd, e := unixSocket(net, laddr, raddr, "dial")
+	if e != nil {
+		return nil, e
+	}
+	return newUnixConn(fd), nil
+}
+
+// UnixListener is a Unix domain socket listener.
+// Clients should typically use variables of type Listener
+// instead of assuming Unix domain sockets.
+type UnixListener struct {
+	fd   *netFD
+	path string
+}
+
+// ListenUnix announces on the Unix domain socket laddr and returns a Unix listener.
+// Net must be "unix" (stream sockets).
+func ListenUnix(net string, laddr *UnixAddr) (l *UnixListener, err os.Error) {
+	if net != "unix" && net != "unixgram" && net != "unixpacket" {
+		return nil, UnknownNetworkError(net)
+	}
+	if laddr != nil {
+		laddr = &UnixAddr{laddr.Name, net} // make our own copy
+	}
+	fd, err := unixSocket(net, laddr, nil, "listen")
+	if err != nil {
+		return nil, err
+	}
+	e1 := syscall.Listen(fd.sysfd, 8) // listenBacklog());
+	if e1 != 0 {
+		closesocket(fd.sysfd)
+		return nil, &OpError{Op: "listen", Net: "unix", Addr: laddr, Error: os.Errno(e1)}
+	}
+	return &UnixListener{fd, laddr.Name}, nil
+}
+
+// AcceptUnix accepts the next incoming call and returns the new connection
+// and the remote address.
+func (l *UnixListener) AcceptUnix() (c *UnixConn, err os.Error) {
+	if l == nil || l.fd == nil {
+		return nil, os.EINVAL
+	}
+	fd, e := l.fd.accept(sockaddrToUnix)
+	if e != nil {
+		return nil, e
+	}
+	c = newUnixConn(fd)
+	return c, nil
+}
+
+// Accept implements the Accept method in the Listener interface;
+// it waits for the next call and returns a generic Conn.
+func (l *UnixListener) Accept() (c Conn, err os.Error) {
+	c1, err := l.AcceptUnix()
+	if err != nil {
+		return nil, err
+	}
+	return c1, nil
+}
+
+// Close stops listening on the Unix address.
+// Already accepted connections are not closed.
+func (l *UnixListener) Close() os.Error {
+	if l == nil || l.fd == nil {
+		return os.EINVAL
+	}
+
+	// The operating system doesn't clean up
+	// the file that announcing created, so
+	// we have to clean it up ourselves.
+	// There's a race here--we can't know for
+	// sure whether someone else has come along
+	// and replaced our socket name already--
+	// but this sequence (remove then close)
+	// is at least compatible with the auto-remove
+	// sequence in ListenUnix.  It's only non-Go
+	// programs that can mess us up.
+	if l.path[0] != '@' {
+		syscall.Unlink(l.path)
+	}
+	err := l.fd.Close()
+	l.fd = nil
+	return err
+}
+
+// Addr returns the listener's network address.
+func (l *UnixListener) Addr() Addr { return l.fd.laddr }
+
+// SetTimeout sets the deadline associated wuth the listener
+func (l *UnixListener) SetTimeout(nsec int64) (err os.Error) {
+	if l == nil || l.fd == nil {
+		return os.EINVAL
+	}
+	return setTimeout(l.fd, nsec)
+}
+
+// File returns a copy of the underlying os.File, set to blocking mode.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+func (l *UnixListener) File() (f *os.File, err os.Error) { return l.fd.dup() }
+
+// ListenUnixgram listens for incoming Unix datagram packets addressed to the
+// local address laddr.  The returned connection c's ReadFrom
+// and WriteTo methods can be used to receive and send UDP
+// packets with per-packet addressing.  The network net must be "unixgram".
+func ListenUnixgram(net string, laddr *UnixAddr) (c *UDPConn, err os.Error) {
+	switch net {
+	case "unixgram":
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	if laddr == nil {
+		return nil, &OpError{"listen", "unixgram", nil, errMissingAddress}
+	}
+	fd, e := unixSocket(net, laddr, nil, "listen")
+	if e != nil {
+		return nil, e
+	}
+	return newUDPConn(fd), nil
+}