# File lib/archive/tar/minitar.rb, line 400
400:     def mkdir(name, opts = {})
401:       raise ClosedStream if @closed
402:       name, prefix = split_name(name)
403:       header = { :name => name, :mode => opts[:mode], :typeflag => "5",
404:                  :size => 0, :gid => opts[:gid], :uid => opts[:uid],
405:                  :mtime => opts[:mtime], :prefix => prefix }
406:       header = Archive::Tar::PosixHeader.new(header).to_s
407:       @io.write(header)
408:       nil
409:     end