Golang snippet to detect file duplicates in a directory by comparing MD5 checksums.

detect_file_dupes.go

// Tool to check for duplicates in a directory by calculating and comparing
//   md5 checksums on the directory contents

package main

import (
	"crypto/md5"
	"encoding/hex"
	"fmt"
	"io/ioutil"
	"os"
)

func main() {
	files, _ := ioutil.ReadDir(os.Args[1])
	s, sep := "", ""
	for _, f := range files {
		fullname := os.Args[1] + "/" + f.Name()
		md5sum := checksum(fullname)
		s += sep + f.Name() + "\n" + "MD5 checksum: " + md5sum + "\n"
		sep = "\n"
	}
	fmt.Printf(s + sep)
}

func checksum(fname string) string {
	data, err := ioutil.ReadFile(fname)
	if err != nil {
		fmt.Printf("Error on " + fname)
	}

	sum := md5.Sum(data)
	return hex.EncodeToString(sum[:])
}