/usr/share/gocode/src/code.google.com/p/go.net/ipv6/doc.go is in golang-go.net-dev 0.0~hg20131201-1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 | // Copyright 2013 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 ipv6 implements IP-level socket options for the Internet
// Protocol version 6.
//
// The package provides IP-level socket options that allow
// manipulation of IPv6 facilities. The IPv6 and socket options for
// IPv6 are defined in RFC 2460, RFC 3493 and RFC 3542.
//
//
// Unicasting
//
// The options for unicasting are available for net.TCPConn,
// net.UDPConn and net.IPConn which are created as network connections
// that use the IPv6 transport. When a single TCP connection carrying
// a data flow of multiple packets needs to indicate the flow is
// important, ipv6.Conn is used to set the traffic class field on the
// IPv6 header for each packet.
//
// ln, err := net.Listen("tcp6", "[::]:1024")
// if err != nil {
// // error handling
// }
// defer ln.Close()
// for {
// c, err := ln.Accept()
// if err != nil {
// // error handling
// }
// go func(c net.Conn) {
// defer c.Close()
//
// The outgoing packets will be labeled DiffServ assured forwarding
// class 1 low drop precedence, as known as AF11 packets.
//
// if err := ipv6.NewConn(c).SetTrafficClass(DiffServAF11); err != nil {
// // error handling
// }
// if _, err := c.Write(data); err != nil {
// // error handling
// }
// }(c)
// }
//
//
// Multicasting
//
// The options for multicasting are available for net.UDPConn and
// net.IPconn which are created as network connections that use the
// IPv6 transport. A few network facilities must be prepared before
// you begin multicasting, at a minimum joining network interfaces and
// multicast groups.
//
// en0, err := net.InterfaceByName("en0")
// if err != nil {
// // error handling
// }
// en1, err := net.InterfaceByIndex(911)
// if err != nil {
// // error handling
// }
// group := net.ParseIP("ff02::114")
//
// First, an application listens to an appropriate address with an
// appropriate service port.
//
// c, err := net.ListenPacket("udp6", "[::]:1024")
// if err != nil {
// // error handling
// }
// defer c.Close()
//
// Second, the application joins multicast groups, starts listening to
// the groups on the specified network interfaces. Note that the
// service port for transport layer protocol does not matter with this
// operation as joining groups affects only network and link layer
// protocols, such as IPv6 and Ethernet.
//
// p := ipv6.NewPacketConn(c)
// if err := p.JoinGroup(en0, &net.UDPAddr{IP: group}); err != nil {
// // error handling
// }
// if err := p.JoinGroup(en1, &net.UDPAddr{IP: group}); err != nil {
// // error handling
// }
//
// The application might set per packet control message transmissions
// between the protocol stack within the kernel. When the application
// needs a destination address on an incoming packet,
// SetControlMessage of ipv6.PacketConn is used to enable control
// message transmissons.
//
// if err := p.SetControlMessage(ipv6.FlagDst, true); err != nil {
// // error handling
// }
//
// The application could identify whether the received packets are
// of interest by using the control message that contains the
// destination address of the received packet.
//
// b := make([]byte, 1500)
// for {
// n, rcm, src, err := p.ReadFrom(b)
// if err != nil {
// // error handling
// }
// if rcm.Dst.IsMulticast() {
// if rcm.Dst.Equal(group)
// // joined group, do something
// } else {
// // unknown group, discard
// continue
// }
// }
//
// The application can also send both unicast and multicast packets.
//
// p.SetTrafficClass(DiffServCS0)
// p.SetHopLimit(16)
// if _, err := p.WriteTo(data[:n], nil, src); err != nil {
// // error handling
// }
// dst := &net.UDPAddr{IP: group, Port: 1024}
// wcm := ipv6.ControlMessage{TrafficClass: DiffServCS7, HopLimit: 1}
// for _, ifi := range []*net.Interface{en0, en1} {
// wcm.IfIndex = ifi.Index
// if _, err := p.WriteTo(data[:n], &wcm, dst); err != nil {
// // error handling
// }
// }
// }
//
//
// More multicasting
//
// An application that uses PacketConn may join multiple multicast
// groups. For example, a UDP listener with port 1024 might join two
// different groups across over two different network interfaces by
// using:
//
// c, err := net.ListenPacket("udp6", "[::]:1024")
// if err != nil {
// // error handling
// }
// defer c.Close()
// p := ipv6.NewPacketConn(c)
// if err := p.JoinGroup(en0, &net.UDPAddr{IP: net.ParseIP("ff02::1:114")}); err != nil {
// // error handling
// }
// if err := p.JoinGroup(en0, &net.UDPAddr{IP: net.ParseIP("ff02::2:114")}); err != nil {
// // error handling
// }
// if err := p.JoinGroup(en1, &net.UDPAddr{IP: net.ParseIP("ff02::2:114")}); err != nil {
// // error handling
// }
//
// It is possible for multiple UDP listeners that listen on the same
// UDP port to join the same multicast group. The net package will
// provide a socket that listens to a wildcard address with reusable
// UDP port when an appropriate multicast address prefix is passed to
// the net.ListenPacket or net.ListenUDP.
//
// c1, err := net.ListenPacket("udp6", "[ff02::]:1024")
// if err != nil {
// // error handling
// }
// defer c1.Close()
// c2, err := net.ListenPacket("udp6", "[ff02::]:1024")
// if err != nil {
// // error handling
// }
// defer c2.Close()
// p1 := ipv6.NewPacketConn(c1)
// if err := p1.JoinGroup(en0, &net.UDPAddr{IP: net.ParseIP("ff02::114")}); err != nil {
// // error handling
// }
// p2 := ipv6.NewPacketConn(c2)
// if err := p2.JoinGroup(en0, &net.UDPAddr{IP: net.ParseIP("ff02::114")}); err != nil {
// // error handling
// }
//
// Also it is possible for the application to leave or rejoin a
// multicast group on the network interface.
//
// if err := p.LeaveGroup(en0, &net.UDPAddr{IP: net.ParseIP("ff02::114")}); err != nil {
// // error handling
// }
// if err := p.JoinGroup(en0, &net.UDPAddr{IP: net.ParseIP("ff01::114")}); err != nil {
// // error handling
// }
package ipv6
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