golang log的简单操作

golog.go

package main

import (
	"flag"
	"fmt"
	"log"
	"os"
)

var fpath *string = flag.String("d", "Null", "please input a file path.")

func main() {
	flag.Parse()
	if *fpath == "Null" {
		fmt.Println("please input a file path")
		return
	}

	//检查路径是否存在
	_, err := os.Stat(*fpath)
	if err != nil {
		_, err := os.Create(*fpath)
		if err != nil {
			fmt.Println(err)
		}
	}

	logfile, err := os.OpenFile(*fpath, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0)
	if err != nil {
		fmt.Printf("%s\r\n", err.Error())
		os.Exit(-1)
	}

	defer logfile.Close()
	logger := log.New(logfile, " ", log.Ldate|log.Ltime|log.Llongfile)
	logger.Println("hello")
	logger.Println("oh....")
	logger.Println("test")
}