将内容以覆盖的形式写入文件中

test_overwrite_file.go

package main

import (
	"io/ioutil"
	"time"
)

func main() {
	counter := 0
	go func() {
		for {
			ioutil.WriteFile("./truncate.txt", []byte(fmt.Sprintf("%d", counter)), 0755)
			counter++
			time.Sleep(3 * time.Second)
		}
	}()

	time.Sleep(500 * time.Second)
}