1 files changed, 387 insertions, 0 deletions
diff --git a/src/net/example_test.go b/src/net/example_test.go
new file mode 100644
index 0000000..2c045d7
--- /dev/null
+++ b/src/net/example_test.go
@@ -0,0 +1,387 @@
+// Copyright 2012 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_test
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"time"
+)
+
+func ExampleListener() {
+	// Listen on TCP port 2000 on all available unicast and
+	// anycast IP addresses of the local system.
+	l, err := net.Listen("tcp", ":2000")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer l.Close()
+	for {
+		// Wait for a connection.
+		conn, err := l.Accept()
+		if err != nil {
+			log.Fatal(err)
+		}
+		// Handle the connection in a new goroutine.
+		// The loop then returns to accepting, so that
+		// multiple connections may be served concurrently.
+		go func(c net.Conn) {
+			// Echo all incoming data.
+			io.Copy(c, c)
+			// Shut down the connection.
+			c.Close()
+		}(conn)
+	}
+}
+
+func ExampleDialer() {
+	var d net.Dialer
+	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
+	defer cancel()
+
+	conn, err := d.DialContext(ctx, "tcp", "localhost:12345")
+	if err != nil {
+		log.Fatalf("Failed to dial: %v", err)
+	}
+	defer conn.Close()
+
+	if _, err := conn.Write([]byte("Hello, World!")); err != nil {
+		log.Fatal(err)
+	}
+}
+
+func ExampleDialer_unix() {
+	// DialUnix does not take a context.Context parameter. This example shows
+	// how to dial a Unix socket with a Context. Note that the Context only
+	// applies to the dial operation; it does not apply to the connection once
+	// it has been established.
+	var d net.Dialer
+	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
+	defer cancel()
+
+	d.LocalAddr = nil // if you have a local addr, add it here
+	raddr := net.UnixAddr{Name: "/path/to/unix.sock", Net: "unix"}
+	conn, err := d.DialContext(ctx, "unix", raddr.String())
+	if err != nil {
+		log.Fatalf("Failed to dial: %v", err)
+	}
+	defer conn.Close()
+	if _, err := conn.Write([]byte("Hello, socket!")); err != nil {
+		log.Fatal(err)
+	}
+}
+
+func ExampleIPv4() {
+	fmt.Println(net.IPv4(8, 8, 8, 8))
+
+	// Output:
+	// 8.8.8.8
+}
+
+func ExampleParseCIDR() {
+	ipv4Addr, ipv4Net, err := net.ParseCIDR("192.0.2.1/24")
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println(ipv4Addr)
+	fmt.Println(ipv4Net)
+
+	ipv6Addr, ipv6Net, err := net.ParseCIDR("2001:db8:a0b:12f0::1/32")
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println(ipv6Addr)
+	fmt.Println(ipv6Net)
+
+	// Output:
+	// 192.0.2.1
+	// 192.0.2.0/24
+	// 2001:db8:a0b:12f0::1
+	// 2001:db8::/32
+}
+
+func ExampleParseIP() {
+	fmt.Println(net.ParseIP("192.0.2.1"))
+	fmt.Println(net.ParseIP("2001:db8::68"))
+	fmt.Println(net.ParseIP("192.0.2"))
+
+	// Output:
+	// 192.0.2.1
+	// 2001:db8::68
+	// <nil>
+}
+
+func ExampleIP_DefaultMask() {
+	ip := net.ParseIP("192.0.2.1")
+	fmt.Println(ip.DefaultMask())
+
+	// Output:
+	// ffffff00
+}
+
+func ExampleIP_Equal() {
+	ipv4DNS := net.ParseIP("8.8.8.8")
+	ipv4Lo := net.ParseIP("127.0.0.1")
+	ipv6DNS := net.ParseIP("0:0:0:0:0:FFFF:0808:0808")
+
+	fmt.Println(ipv4DNS.Equal(ipv4DNS))
+	fmt.Println(ipv4DNS.Equal(ipv4Lo))
+	fmt.Println(ipv4DNS.Equal(ipv6DNS))
+
+	// Output:
+	// true
+	// false
+	// true
+}
+
+func ExampleIP_IsGlobalUnicast() {
+	ipv6Global := net.ParseIP("2000::")
+	ipv6UniqLocal := net.ParseIP("2000::")
+	ipv6Multi := net.ParseIP("FF00::")
+
+	ipv4Private := net.ParseIP("10.255.0.0")
+	ipv4Public := net.ParseIP("8.8.8.8")
+	ipv4Broadcast := net.ParseIP("255.255.255.255")
+
+	fmt.Println(ipv6Global.IsGlobalUnicast())
+	fmt.Println(ipv6UniqLocal.IsGlobalUnicast())
+	fmt.Println(ipv6Multi.IsGlobalUnicast())
+
+	fmt.Println(ipv4Private.IsGlobalUnicast())
+	fmt.Println(ipv4Public.IsGlobalUnicast())
+	fmt.Println(ipv4Broadcast.IsGlobalUnicast())
+
+	// Output:
+	// true
+	// true
+	// false
+	// true
+	// true
+	// false
+}
+
+func ExampleIP_IsInterfaceLocalMulticast() {
+	ipv6InterfaceLocalMulti := net.ParseIP("ff01::1")
+	ipv6Global := net.ParseIP("2000::")
+	ipv4 := net.ParseIP("255.0.0.0")
+
+	fmt.Println(ipv6InterfaceLocalMulti.IsInterfaceLocalMulticast())
+	fmt.Println(ipv6Global.IsInterfaceLocalMulticast())
+	fmt.Println(ipv4.IsInterfaceLocalMulticast())
+
+	// Output:
+	// true
+	// false
+	// false
+}
+
+func ExampleIP_IsLinkLocalMulticast() {
+	ipv6LinkLocalMulti := net.ParseIP("ff02::2")
+	ipv6LinkLocalUni := net.ParseIP("fe80::")
+	ipv4LinkLocalMulti := net.ParseIP("224.0.0.0")
+	ipv4LinkLocalUni := net.ParseIP("169.254.0.0")
+
+	fmt.Println(ipv6LinkLocalMulti.IsLinkLocalMulticast())
+	fmt.Println(ipv6LinkLocalUni.IsLinkLocalMulticast())
+	fmt.Println(ipv4LinkLocalMulti.IsLinkLocalMulticast())
+	fmt.Println(ipv4LinkLocalUni.IsLinkLocalMulticast())
+
+	// Output:
+	// true
+	// false
+	// true
+	// false
+}
+
+func ExampleIP_IsLinkLocalUnicast() {
+	ipv6LinkLocalUni := net.ParseIP("fe80::")
+	ipv6Global := net.ParseIP("2000::")
+	ipv4LinkLocalUni := net.ParseIP("169.254.0.0")
+	ipv4LinkLocalMulti := net.ParseIP("224.0.0.0")
+
+	fmt.Println(ipv6LinkLocalUni.IsLinkLocalUnicast())
+	fmt.Println(ipv6Global.IsLinkLocalUnicast())
+	fmt.Println(ipv4LinkLocalUni.IsLinkLocalUnicast())
+	fmt.Println(ipv4LinkLocalMulti.IsLinkLocalUnicast())
+
+	// Output:
+	// true
+	// false
+	// true
+	// false
+}
+
+func ExampleIP_IsLoopback() {
+	ipv6Lo := net.ParseIP("::1")
+	ipv6 := net.ParseIP("ff02::1")
+	ipv4Lo := net.ParseIP("127.0.0.0")
+	ipv4 := net.ParseIP("128.0.0.0")
+
+	fmt.Println(ipv6Lo.IsLoopback())
+	fmt.Println(ipv6.IsLoopback())
+	fmt.Println(ipv4Lo.IsLoopback())
+	fmt.Println(ipv4.IsLoopback())
+
+	// Output:
+	// true
+	// false
+	// true
+	// false
+}
+
+func ExampleIP_IsMulticast() {
+	ipv6Multi := net.ParseIP("FF00::")
+	ipv6LinkLocalMulti := net.ParseIP("ff02::1")
+	ipv6Lo := net.ParseIP("::1")
+	ipv4Multi := net.ParseIP("239.0.0.0")
+	ipv4LinkLocalMulti := net.ParseIP("224.0.0.0")
+	ipv4Lo := net.ParseIP("127.0.0.0")
+
+	fmt.Println(ipv6Multi.IsMulticast())
+	fmt.Println(ipv6LinkLocalMulti.IsMulticast())
+	fmt.Println(ipv6Lo.IsMulticast())
+	fmt.Println(ipv4Multi.IsMulticast())
+	fmt.Println(ipv4LinkLocalMulti.IsMulticast())
+	fmt.Println(ipv4Lo.IsMulticast())
+
+	// Output:
+	// true
+	// true
+	// false
+	// true
+	// true
+	// false
+}
+
+func ExampleIP_IsPrivate() {
+	ipv6Private := net.ParseIP("fc00::")
+	ipv6Public := net.ParseIP("fe00::")
+	ipv4Private := net.ParseIP("10.255.0.0")
+	ipv4Public := net.ParseIP("11.0.0.0")
+
+	fmt.Println(ipv6Private.IsPrivate())
+	fmt.Println(ipv6Public.IsPrivate())
+	fmt.Println(ipv4Private.IsPrivate())
+	fmt.Println(ipv4Public.IsPrivate())
+
+	// Output:
+	// true
+	// false
+	// true
+	// false
+}
+
+func ExampleIP_IsUnspecified() {
+	ipv6Unspecified := net.ParseIP("::")
+	ipv6Specified := net.ParseIP("fe00::")
+	ipv4Unspecified := net.ParseIP("0.0.0.0")
+	ipv4Specified := net.ParseIP("8.8.8.8")
+
+	fmt.Println(ipv6Unspecified.IsUnspecified())
+	fmt.Println(ipv6Specified.IsUnspecified())
+	fmt.Println(ipv4Unspecified.IsUnspecified())
+	fmt.Println(ipv4Specified.IsUnspecified())
+
+	// Output:
+	// true
+	// false
+	// true
+	// false
+}
+
+func ExampleIP_Mask() {
+	ipv4Addr := net.ParseIP("192.0.2.1")
+	// This mask corresponds to a /24 subnet for IPv4.
+	ipv4Mask := net.CIDRMask(24, 32)
+	fmt.Println(ipv4Addr.Mask(ipv4Mask))
+
+	ipv6Addr := net.ParseIP("2001:db8:a0b:12f0::1")
+	// This mask corresponds to a /32 subnet for IPv6.
+	ipv6Mask := net.CIDRMask(32, 128)
+	fmt.Println(ipv6Addr.Mask(ipv6Mask))
+
+	// Output:
+	// 192.0.2.0
+	// 2001:db8::
+}
+
+func ExampleIP_String() {
+	ipv6 := net.IP{0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+	ipv4 := net.IPv4(10, 255, 0, 0)
+
+	fmt.Println(ipv6.String())
+	fmt.Println(ipv4.String())
+
+	// Output:
+	// fc00::
+	// 10.255.0.0
+}
+
+func ExampleIP_To16() {
+	ipv6 := net.IP{0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+	ipv4 := net.IPv4(10, 255, 0, 0)
+
+	fmt.Println(ipv6.To16())
+	fmt.Println(ipv4.To16())
+
+	// Output:
+	// fc00::
+	// 10.255.0.0
+}
+
+func ExampleIP_to4() {
+	ipv6 := net.IP{0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+	ipv4 := net.IPv4(10, 255, 0, 0)
+
+	fmt.Println(ipv6.To4())
+	fmt.Println(ipv4.To4())
+
+	// Output:
+	// <nil>
+	// 10.255.0.0
+}
+
+func ExampleCIDRMask() {
+	// This mask corresponds to a /31 subnet for IPv4.
+	fmt.Println(net.CIDRMask(31, 32))
+
+	// This mask corresponds to a /64 subnet for IPv6.
+	fmt.Println(net.CIDRMask(64, 128))
+
+	// Output:
+	// fffffffe
+	// ffffffffffffffff0000000000000000
+}
+
+func ExampleIPv4Mask() {
+	fmt.Println(net.IPv4Mask(255, 255, 255, 0))
+
+	// Output:
+	// ffffff00
+}
+
+func ExampleUDPConn_WriteTo() {
+	// Unlike Dial, ListenPacket creates a connection without any
+	// association with peers.
+	conn, err := net.ListenPacket("udp", ":0")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer conn.Close()
+
+	dst, err := net.ResolveUDPAddr("udp", "192.0.2.1:2000")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// The connection can write data to the desired address.
+	_, err = conn.WriteTo([]byte("data"), dst)
+	if err != nil {
+		log.Fatal(err)
+	}
+}