# File lib/archive/tar/minitar.rb, line 394
394:     def mkdir(name, opts = {})
395:       raise ClosedStream if @closed
396:       name, prefix = split_name(name)
397:       header = { :name => name, :mode => opts[:mode], :typeflag => "5",
398:                  :size => 0, :gid => opts[:gid], :uid => opts[:uid],
399:                  :mtime => opts[:mtime], :prefix => prefix }
400:       header = Archive::Tar::PosixHeader.new(header).to_s
401:       @io.write(header)
402:       nil
403:     end