This directory contains component macro .def files that are referenced by X-Macros in
the ptpd source code.

The component macros are used to define message, derived data
types, and management TLV fields.

The X-Macros are used to automatically generate most of
the code used to pack, unpack, and free ptp data fields.

Documentation on how to use X-Macros can be found at:
http://en.wikibooks.org/wiki/C_Programming/Preprocessor#X-Macros
