Self-Describing Data

Rendezvous programs exchange self-describing data. Each item of self-describing data consists of up to six parts:

• Data	The data itself.
• Type	An indicator to manipulate and interpret the data as an integer, a string, a composite message, or other datatype.
• Size	The number of bytes that the data occupies.
• Name	The subject name of the message, or the name of a field within a message.
• Identifier	An optional integer that uniquely identifies a field within a message.
• Count	The number of elements in an array datatype.

Between sender and listener, Rendezvous software uses this descriptive information to automatically convert messages between the local data format and Rendezvous wire format—a universal format that is independent of hardware, operating system, and programming language architectures. The universal wire format provides a common language to connect diverse programs. For details see Rendezvous Datatypes.