52 lines
932 B
Go
52 lines
932 B
Go
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// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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// See page 223.
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// Reverb1 is a TCP server that simulates an echo.
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package main
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import (
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"bufio"
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"fmt"
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"log"
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"net"
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"strings"
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"time"
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)
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//!+
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func echo(c net.Conn, shout string, delay time.Duration) {
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fmt.Fprintln(c, "\t", strings.ToUpper(shout))
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time.Sleep(delay)
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fmt.Fprintln(c, "\t", shout)
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time.Sleep(delay)
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fmt.Fprintln(c, "\t", strings.ToLower(shout))
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}
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func handleConn(c net.Conn) {
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input := bufio.NewScanner(c)
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for input.Scan() {
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echo(c, input.Text(), 1*time.Second)
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}
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// NOTE: ignoring potential errors from input.Err()
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c.Close()
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}
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//!-
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func main() {
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l, err := net.Listen("tcp", "localhost:8000")
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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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conn, err := l.Accept()
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if err != nil {
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log.Print(err) // e.g., connection aborted
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continue
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}
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go handleConn(conn)
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}
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}
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