md2pdf.rb

#!/usr/bin/env ruby
# -*- coding: utf-8; -*-

require 'rubygems'
require 'pathname'
require 'github/markdown'

Dir['*.md'].each do |md|
  target = Pathname.new(md)
  header = <<-HEADER
\\documentclass[a4paper]{report}
\\usepackage{hyperref}
\\usepackage{ctable}
\\setcounter{chapter}{1}

\\begin{document}
HEADER
  footer = <<-FOOTER
\\end{document}
FOOTER

  html_file = target.sub(/\.md\z/, '.html')
  tex_file  = target.sub(/\.md\z/, '.tex')
  dvi_file  = target.sub(/\.md\z/, '.dvi')

  html = GitHub::Markdown.render(File.open(md).read)
  open(html_file, 'wb' ) {|f| f.write html }

  tex = `pandoc --to=latex #{html_file}`
  open(tex_file, 'wb' ) {|f| f.write header + tex + footer }
  `platex -kanji=utf-8 #{tex_file}`
  `dvipdfmx #{dvi_file}`
end