|Informative Information for the Uninformed
Two separate file descriptor lists are maintained; destinations for inbound data and sources of outbound data. The data structure for storage of a file descriptor and its data for inclusion in either list is defined in Figure below.
The independence of the file descriptor lists from the outbound data polling and message handler components provides for a flexible and versatile environment within which to expand functionality. In order to include new data types for transfer, all that is required is to define a new data type ID for both applications to correlate messages upon, open a file descriptor to the appropriate place to read or write the data, and include the file descriptor in the appropriate list.