Merge 2 csv files line by line in Go via goroutines

mergecsv.go

// go build -ldflags "-s -w" .\mergecsv.go
// analyse 2 csv files line by line sequentially via goroutines
// 04/2021

package main

import (
	"bufio"
	"fmt"
	"log"
	"math/rand"
	"os"
	"time"
)

func file(name string) *os.File {
	file, err := os.Open(name)
	if err != nil {
		log.Fatal(err)
	}
	return file
}

func fn1(c chan string, fileName string) {
	file := file(fileName)
	defer file.Close()
	defer close(c)

	scanner1 := bufio.NewScanner(file)
	for scanner1.Scan() {
		var msec = rand.Intn(1)
		time.Sleep(time.Duration(msec) * time.Millisecond)
		c <- scanner1.Text()
	}
}

func main() {
	rand.Seed(time.Now().Unix())
	c1, c2 := make(chan string), make(chan string)

	go fn1(c1, "file1.txt")
	go fn1(c2, "file2.txt")

	for {
		msg1, ok1 := <-c1
		msg2, ok2 := <-c2

		if !ok1 && !ok2 {
			break
		}
		fmt.Printf("one: %s\n", msg1)
		fmt.Printf("two: %s\n", msg2)
	}
}