ちょっとふるいぞ。
ruby -v ruby 2.0.0p648 (2015-12-16 revision 53162) [universal.x86_64-darwin15]
こういうやつ。
Dir::glob("/home/shigemk2/test/*.csv").each {|f| p f file = File.open(f + "-new.csv","a") File.open(f, 'r:utf-8') do |f| f.each_line do |line| file.puts line.chomp + "\thoge\n" end end }