# File lib/rubytorrent/message.rb, line 25
  def to_fbbe # four-byte big-endian integer
    raise "fbbe must be < 2^32" unless self <= 2**32
    raise "fbbe must be >= 0" unless self >= 0
    s = "    "
    s[0] = (self >> 24) % 256
    s[1] = (self >> 16) % 256
    s[2] = (self >>  8) % 256
    s[3] = (self      ) % 256
    s
  end