The LLP client and server components described in these sections are included for legacy backward compatibility only. They are not supported for new application development. If you are developing a new application, use Iguana as the transport mechanism for sending messages over LLP, and use the Iguana plugin API to define an interface between your application and the Iguana server. For more details on using plugins in Iguana, see Working With Plugins. For reasons why you should use Iguana instead of Chameleon for your LLP solution, see Why Choose Iguana Over Chameleon?.

Under Windows, if the application is a GUI application, then a Windows message loop already exists, and there is no need to create a message loop. If the socket components are used in a console application or service application, it is important to create a message loop using the methods supplied by the LLP components. For more information, see Running the LLP Components in a Windows Service.

Under Unix and Linux applications, the event loop is proprietary to Chameleon. Internally, the components are invoking the POSIX ::select call, and so it is always necessary to make use of the methods supplied on the LLP components to run a message loop. For more information, see Running the LLP Components in Linux/Unix.

	It is important to understand that the messages handled by the message loop are not HL7 messages - they are operating system messages like "data received", "connection closed", etc.