This is a simple netcat implementation in go.

netcat.go

/*
 * This is a simple netcat implementation in go.
 * Test this program in terminal:
 * 
 *   $ go run simplerouter.go
 *   GET / HTTP/1.0<CR>
 *   <CR>
 *   HTTP/1.0 302 Found
 *   ...
 *
 */

package main

import (
    "io"
    "os"
    "log"
    "net"
    "strings"
)

var quit chan bool

func io2io(src io.Reader, dst io.Writer) {
    defer func() { quit <- true }()

    buf := make([]byte, 8192)
    for {
        n, err := src.Read(buf)
        if err != nil {
            if err != io.EOF {
                log.Println("read error:", err)
            }
            break
        }

        str := strings.Replace(string(buf[:n]), "\n", "\r\n", -1)

        _, err = dst.Write([]byte(str))
        if err != nil {
            log.Println("write error:", err)
            break
        }
    }
}

func main() {
    quit = make(chan bool)

    conn, err := net.Dial("tcp", "www.google.com:80")
    if err != nil {
        log.Println("failed to connect:", err)
        os.Exit(1)
    }

    go io2io(os.Stdin, conn)
    go io2io(conn, os.Stdout)

    select {
    case <-quit:
        return
    }
}