pip_demo.go

package main

import (
	"fmt"
	"io"
	"io/ioutil"
	"log"
	"sync"
)

var wg sync.WaitGroup

func checkError(err error) {
	if err != nil {
		log.Fatal("[ERROR] ", err)
	}
}

func main() {
	wg.Add(2)

	pipR, pipW := io.Pipe()

	go func() {
		defer wg.Done()
		defer pipR.Close()
		buf, err := ioutil.ReadAll(pipR)
		checkError(err)
		fmt.Println("Read() finished, content =", string(buf))
	}()

	go func() {
		defer wg.Done()
		defer pipW.Close()
		n, err := pipW.Write([]byte("Hello World!"))
		checkError(err)
		fmt.Println("Write() finished, wrote", n, "bytes")
	}()

	wg.Wait()
}