package main

import (
	"io"
	"log"
	"os"
)

func main() {

	err := WriteString("hello world")
	if err != nil {
		log.Fatalln(err)
	}
}

func WriteString(str string) (err error) {
	var f *os.File
	f, err = os.Create("./notes.txt")
	if err != nil {
		return
	}

	defer func() {
		cerr := f.Close()
		if err == nil {
			err = cerr
		}
	}()

	_, err = io.WriteString(f, str)
	return
}