create a backup of files

backup.go

// Copyright 2017 Kranz. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package main

import (
	"os/exec"
	"log"
	"os"
	"time"
	"fmt"
)

var (
	fileNameBackup string = time.Now().Format("20060102150405")
	fileNameError  string = "error"
	dirName        string = "log"
)

func main() {
	// Backup file
	fileBackup, err := os.Create(fmt.Sprintf("%v/%v.log", dirName, fileNameBackup))
	if err != nil {
		log.Fatalf("Error to create file: %v", err.Error())
		os.Exit(1)
	}
	defer fileBackup.Close()

	// Error File
	fileError, err := os.Create(fmt.Sprintf("%v/%v.log", dirName, fileNameError))
	if err != nil {
		log.Fatalf("Error to create file: %v", err.Error())
		os.Exit(1)
	}
	defer fileError.Close()

	// Execute command
	cmd := exec.Command("_mysql", "-h localhost")
	cmd.Stdout = fileBackup // return only out of file
	cmd.Stderr = fileError  // return error

	// execute command
	if err := cmd.Run(); err != nil {
		log.Fatalf("Error to exec: %v", err.Error())
		os.Exit(1)
	}

	// everything is ok.
	log.Print("command finished!")
	os.Exit(0)
}