Files
learngo/x-tba/slices/15-empty-file-finder/main.go
T
2019-01-22 01:47:11 +03:00

68 lines
1.2 KiB
Go

// For more tutorials: https://blog.learngoprogramming.com
//
// Copyright © 2018 Inanc Gumus
// Learn Go Programming Course
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
//
package main
import (
"fmt"
"io/ioutil"
"os"
)
// You can easily write to a file using bash.
//
// However, when what you're creating is a library,
// then you won't have that option. So, it's good to learn
// how to write to a file using a byte slice.
// ioutil.ReadDir
// os.FileInfo
func main() {
args := os.Args[1:]
if len(args) == 0 {
fmt.Println("Provide a directory")
return
}
files, err := ioutil.ReadDir(args[0])
if err != nil {
fmt.Println(err)
return
}
var data []byte
// optimize:
// var total int
// for _, file := range files {
// if file.Size() == 0 {
// // +1 for the newline character
// total += len(file.Name()) + 1
// }
// }
// data := make([]byte, 0, total)
for _, file := range files {
if file.Size() == 0 {
name := file.Name()
// fmt.Println(name)
data = append(data, name...)
data = append(data, '\n')
}
}
ioutil.WriteFile("out.txt", data, 0644)
fmt.Printf("%s", data)
}
// See: https://www.tutorialspoint.com/unix/unix-file-permission.htm
// See: http://permissions-calculator.org/