Simple reader/writer in Go

echo-simple.go

package main

import (
    "bufio"
	"fmt"
	"log"
	"os"
)

func reader(path string, p chan string) {
	f, err := os.Open(path)
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()
	buf := bufio.NewReader(f)
	for {
		line, err := buf.ReadString('\n')
		if err != nil {
			break
		}
		p <- line
	}
}

func writer(p chan string) {
	for line := range p {
		fmt.Print(line)
	}
}

func main() {
	p := make(chan string)
	go func() { reader(os.Args[1], p); close(p) }()
	writer(p)
}

echo.go

package main

import (
	"bufio"
	"fmt"
	"log"
	"os"
)

func reader(path string, p chan string) {
	f, err := os.Open(path)
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()
	buf := bufio.NewReader(f)
	for {
		line, err := buf.ReadString('\n')
		if err != nil {
			break
		}
		p <- line
	}
}

func writer(p chan string) {
	for line := range p {
		fmt.Print(line)
	}
}

func main() {
	p := make(chan string, 10)
	qr := make(chan int)
	qw := make(chan int)

	for i := 1; i < len(os.Args); i++ {
		go func(i int) { reader(os.Args[i], p); qr <- 1 }(i)
	}
	go func() { writer(p); qw <- 1 }()

	for i := 1; i < len(os.Args); i++ {
		<-qr
	}
	close(p)

	<-qw
}