如何显示执行代码所在文件和行号？ 使用go中的log.Println()实现

实现在控制台和日志文件中打印日志? 使用log.SetOutput()实现

package main

import (
	"io"
	"log"
	"os"
	"runtime"
	"time"
)

type Logger struct{}

func main() {
	logger := Logger{}
	logger.Log()
}

// Logs the message to both console and log file.
func (c Logger) Log() {
	// If logs.txt doesn't exist, it will be created.
	file, err := os.OpenFile("./logs/logs_"+time.Now().Format("2006-01-02")+".txt", os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0666)
	if err != nil {
		log.Fatal(err)
	}

	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)
	log.SetOutput(io.MultiWriter(file, os.Stdout)) // Sets the output to both file and console
	log.Println("log is working!")
}

// Gets the name of the running function.
func (c Logger) runFuncName() string {
	pc := make([]uintptr, 1)
	runtime.Callers(2, pc)
	f := runtime.FuncForPC(pc[0])
	return f.Name()
}