45 lines
622 B
Go
45 lines
622 B
Go
package main
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import (
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"flag"
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"log"
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"net"
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)
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var (
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laddr string
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)
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func init() {
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log.SetFlags(log.LstdFlags | log.Lshortfile)
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flag.StringVar(&laddr, "L", ":8080", "listen address")
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flag.Parse()
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}
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func main() {
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udpEchoServer()
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}
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func udpEchoServer() {
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addr, err := net.ResolveUDPAddr("udp", laddr)
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if err != nil {
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log.Fatal(err)
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}
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conn, err := net.ListenUDP("udp", addr)
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if err != nil {
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log.Fatal(err)
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}
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for {
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b := make([]byte, 1024)
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n, raddr, err := conn.ReadFromUDP(b)
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if err != nil {
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log.Fatal(err)
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}
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if _, err = conn.WriteToUDP(b[:n], raddr); err != nil {
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log.Fatal(err)
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}
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}
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}
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