List all the files with suffix .csv (e.g.) in directory "./" (e.g.)

cat_all

#!/usr/bin/env ruby

require "find"

def get_opts
  require 'trollop'

  opts = Trollop::options do
    version "#{File.basename($PROGRAM_NAME)} 1.0.0 (c) 2014 Wubin Qu"
    banner <<-EOS
    List all the files with suffix .csv (e.g.) in directory "./" (e.g.)

    Usage:

    #{File.basename($PROGRAM_NAME)} [options]

    EOS

    opt :dir, "e.g. /home, /opt/, ./ etc.", type: :string, required: true
    opt :suffix, "e.g. .csv, .fasta etc.", type: :string, required: true
    opt :out, "Concatenate the contents into Out file.", type: :string, required: true
  end

  opts
end


if $0 == __FILE__
  opts = get_opts

  File.open(opts.out, "a") do |oh|
    Find.find(opts.dir) do |file|
      next unless file.end_with?(opts.suffix)
      File.foreach(File.join(opts.dir, file)) do |line|
        oh.write(line)
      end
    end
  end
end