csv.go

package main

import (
    "bufio"
    "encoding/csv"
    "fmt"
    "log"
    "os"
    "strings"
    "time"
    "sync"
)

func main() {
    file, err := os.Open("caribbean.csv")
    if err != nil {
        log.Fatal(err)
    }
    defer file.Close()
    scanner := bufio.NewScanner(file)
    wg := &sync.WaitGroup{}
    for scanner.Scan() {
        line := scanner.Text()
        wg.Add(1)
        go func() {
            defer wg.Done()
            parseCSV(line)
        }()
    }
    wg.Wait()
    if err := scanner.Err(); err != nil {
        log.Fatal(err)
    }
    fmt.Println("---------------------------DONE------------------------------")
}

func parseCSV(s string) {
    r := csv.NewReader(strings.NewReader(s))
    record, err := r.Read()
    if err != nil {
        log.Fatal("Read error: ", err)
    }
    time.Sleep(time.Millisecond * 10) // 10msの処理をさせる
    fmt.Println(record[3])            // タイトルを表示
}