binary?

# File lib/rdoc/parser.rb, line 73
  def self.binary?(file)
    return false if file =~ /\.(rdoc|txt)$/

    s = File.read(file, 1024) or return false

    return true if s[0, 2] == Marshal.dump('')[0, 2] or s.index("\x00")

    mode = 'r:utf-8' # default source encoding has been chagened to utf-8
    s.sub!(/\A#!.*\n/, '')     # assume shebang line isn't longer than 1024.
    encoding = s[/^\s*\#\s*(?:-\*-\s*)?(?:en)?coding:\s*([^\s;]+?)(?:-\*-|[\s;])/, 1]
    mode = "rb:#{encoding}" if encoding
    s = File.open(file, mode) {|f| f.gets(nil, 1024)}

    not s.valid_encoding?
  end