├── README.md
├── main.go
└── screenshot.gif


/README.md:
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 1 | # nyan-ping
 2 | 
 3 | にゃーん
 4 | 
 5 | ![にゃーん](https://raw.githubusercontent.com/mattn/nyan-ping/master/screenshot.gif)
 6 | 
 7 | ## Usage
 8 | 
 9 | ```
10 | Usage of nyan-ping:
11 |   -6	ip6
12 |   -s duration
13 |     	sleep (default 1ms)
14 |   -t duration
15 |     	timeout (default 100ms)
16 | ```
17 | 
18 | ## Installation
19 | 
20 | ```
21 | $ go get github.com/mattn/nyan-ping
22 | ```
23 | 
24 | ## License
25 | 
26 | MIT
27 | 
28 | ## Author
29 | 
30 | Yasuhiro Matsumoto (a.k.a. mattn)
31 | 


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/main.go:
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 1 | package main
 2 | 
 3 | import (
 4 | 	"flag"
 5 | 	"fmt"
 6 | 	"log"
 7 | 	"net"
 8 | 	"os"
 9 | 	"time"
10 | 
11 | 	"golang.org/x/net/icmp"
12 | 	"golang.org/x/net/ipv4"
13 | )
14 | 
15 | func main() {
16 | 	var sleep time.Duration
17 | 	var timeout time.Duration
18 | 	var ipv6 bool
19 | 
20 | 	flag.DurationVar(&sleep, "s", 1*time.Millisecond, "sleep")
21 | 	flag.DurationVar(&timeout, "t", 100*time.Millisecond, "timeout")
22 | 	flag.BoolVar(&ipv6, "6", false, "ip6")
23 | 	flag.Parse()
24 | 
25 | 	proto := "ip4"
26 | 	host := "pong4.kooshin.net"
27 | 	if ipv6 {
28 | 		proto = "ip6"
29 | 		host = "pong6.kooshin.net"
30 | 	}
31 | 
32 | 	ip, err := net.ResolveIPAddr(proto, host)
33 | 	if err != nil {
34 | 		log.Fatalf("ResolveIPAddr: %v", err)
35 | 	}
36 | 
37 | 	c, err := icmp.ListenPacket(proto+":icmp", "0.0.0.0")
38 | 	if err != nil {
39 | 		log.Fatalf("ListenPacket: %v", err)
40 | 	}
41 | 	defer c.Close()
42 | 
43 | 	for i := 1; i <= 1400; i++ {
44 | 		wm := icmp.Message{
45 | 			Type: ipv4.ICMPTypeEcho,
46 | 			Code: 0,
47 | 			Body: &icmp.Echo{
48 | 				ID: os.Getpid() & 0xffff, Seq: i,
49 | 				Data: []byte("HELLO-R-U-THERE"),
50 | 			},
51 | 		}
52 | 		wb, err := wm.Marshal(nil)
53 | 		if err != nil {
54 | 			log.Fatalf("Marshal: %v", err)
55 | 		}
56 | 		if _, err := c.WriteTo(wb, &net.IPAddr{IP: ip.IP}); err != nil {
57 | 			log.Fatalf("WriteTo: %v", err)
58 | 		}
59 | 
60 | 		c.SetReadDeadline(time.Now().Add(timeout))
61 | 		rb := make([]byte, 1500)
62 | 		n, _, err := c.ReadFrom(rb)
63 | 		if err != nil {
64 | 			fmt.Print("U")
65 | 		} else {
66 | 			rm, err := icmp.ParseMessage(ipv4.ICMPTypeEcho.Protocol(), rb[:n])
67 | 			if err == nil && rm.Type == ipv4.ICMPTypeEchoReply {
68 | 				fmt.Print("!")
69 | 			} else {
70 | 				fmt.Print("U")
71 | 			}
72 | 		}
73 | 		if i%70 == 0 {
74 | 			fmt.Println()
75 | 		}
76 | 		time.Sleep(sleep)
77 | 	}
78 | }
79 | 


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/screenshot.gif:
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https://raw.githubusercontent.com/mattn/nyan-ping/be305b6e24699f5bee47f793e706b76ffa5c47e6/screenshot.gif


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