#!/bin/sh

# headerがついてるなら↓
ruby -rcsv -e 'File.write("#{ARGV[0]}_utf8.csv", CSV.read(ARGV[0], headers: true, encoding: "CP932:UTF-8"))' "hoge_target_file"

# headerがついてないなら↓
ruby -rcsv -e 'File.write("#{ARGV[0]}_utf8.csv", CSV.read(ARGV[0],                encoding: "CP932:UTF-8"))' "hoge_target_file"