# File lib/automateit/package_manager/yum.rb, line 13
  def installed?(*packages)
    return _installed_helper?(*packages) do |list, opts|
      ### rpm -q --nosignature --nodigest --qf "%{NAME} # %{VERSION} # %{RELEASE}\n" httpd nomarch foo
      cmd = 'rpm -q --nosignature --nodigest --qf "%{NAME} # %{VERSION} # %{RELEASE}\n"'
      list.each{|package| cmd << " "+package}
      cmd << " 2>&1" # missing packages are listed on STDERR

      log.debug(PEXEC+cmd)
      data = `#{cmd}`
      matches = data.scan(/^(.+) # (.+) # .+$/)
      available = matches.inject([]) do |sum, match|
        package, status = match
        sum << package
        sum
      end
      available
    end
  end