anchor.diff:            type = types.str;
             default = "";
             description = "Additional command line parameters";
  -          example = "-P mysecurepassword -l 192.168.1.10 -p 23";
  +          example = "-l 192.168.1.10 -p 23";
  +        };
  +
  +        passwordFile = mkOption {
  +          type = types.str;
  +          default = "";
  +          description = "File that containts password";
           };
         };
   
  
positive.code:           foo = {
              server = "tunnel.mdomain.com";
              relay = "8.8.8.8";
              extraConfig = "-P mysecurepassword";
            }
          }
          '';
  
negative.code:         description = "iodine, ip over dns server daemon";
          after = [ "network.target" ];
          wantedBy = [ "multi-user.target" ];
          preStart = ''
            cat > /run/iodined/script << EOF
              #!/bin/sh
              ${pkgs.iodine}/bin/iodined -f -u ${iodinedUser} ${cfg.server.extraConfig} ${optionalString (cfg.passwordFile != "") "-P $(cat \"${cfg.passwordFile}\")"} ${cfg.server.ip} ${cfg.server.domain}
            EOF
            chmod 700 /run/iodined/script
          '';
          script = "/run/iodined/script";
          serviceConfig.RuntimeDirectory = [ "iodined" ];
        };
      };
  
  