# File lib/net/ldap.rb, line 529
    def open
      raise LdapError.new( "open already in progress" ) if @open_connection
      begin
        @open_connection = Connection.new( :host => @host, :port => @port, :encryption => @encryption )
        @open_connection.bind @auth
        yield self
      ensure
        @open_connection.close if @open_connection
        @open_connection = nil
      end
    end