IDL provides both a number of primitive data types - such as various sizes of integers and floats, bytes, and booleans - as well as pointers and a variety of constructed types based on the primitive types. The use of the primitive types is quite straightforward. The only important policy issues have to do with IDL data type to C data type mappings and with character handling. Pointers and the constructed types raise many more policy and style issues, and the bulk of this topic is devoted to describing them.
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