Write README.md

README.md

@@ -1,4 +1,45 @@
 go-fastping
 ===========
 
-go-fastping is a Go language port of AnyEvent::FastPing Perl module to send ICMP ECHO REQUEST packets quickly
+go-fastping is a Go language port of Marc Lehmann's AnyEvent::FastPing Perl
+module to send ICMP ECHO REQUEST packets quickly. Original Perl module is
+available at
+http://search.cpan.org/~mlehmann/AnyEvent-FastPing-2.01/
+
+It hasn't been fully implemented original functions yet and only for IPv4 now.
+
+## Installation
+
+Install and update this go package with `go get -u github.com/tatsushid/go-fastping`
+
+## Examples
+
+Import this package and write
+
+```go
+p := fastping.NewPinger()
+ra, err := net.ResolveIPAddr("ip4:icmp", os.Args[1])
+if err != nil {
+	fmt.Println(err)
+	os.Exit(1)
+}
+p.AddIPAddr(ra)
+p.AddHandler("receive", func(addr *net.IPAddr, rtt time.Duration) {
+	fmt.Printf("IP Addr: %s receive, RTT: %v\n", addr.String(), rtt)
+})
+p.AddHandler("idle", func() {
+	fmt.Println("finish")
+})
+p.Run()
+```
+
+It sends an ICMP packet and wait a response. If it receives a response, it
+calls "receive" callback. After that, MaxRTT time passed, it calls "idle"
+callback. For more detail, refer [godoc][godoc] and If you need more example,
+please see "cmd/ping/ping.go".
+
+## License
+go-fastping is under MIT License. See the [LICENSE][license] file for details.
+
+[godoc]: http://godoc.org/github.com/tatsushid/go-fastping
+[license]: https://github.com/tatsushid/go-fastping/blob/master/LICENSE