Net::FTP#close

# File tmp/rubies/ruby-3.0.5/lib/net/ftp.rb, line 1363
def close
  if @sock and not @sock.closed?
    begin
      @sock.shutdown(Socket::SHUT_WR) rescue nil
      orig, self.read_timeout = self.read_timeout, 3
      @sock.read rescue nil
    ensure
      @sock.close
      self.read_timeout = orig
    end
  end
end