# File lib/net/ssh/known_hosts.rb, line 121
121:     def add(host, key)
122:       File.open(source, "a") do |file|
123:         blob = [Net::SSH::Buffer.from(:key, key).to_s].pack("m*").gsub(/\s/, "")
124:         file.puts "#{host} #{key.ssh_type} #{blob}"
125:       end
126:     end