PR_EXTERN ========= Used to define the prototypes for functions or variables that are to be exported from a shared library. Syntax ------ .. code:: #include PR_EXTERN(type)prototype Description ----------- :ref:`PR_EXTERN` is used to define externally visible routines and globals. For syntax details for each platform, see `prtypes.h `__. The macro includes the proper specifications to declare the target ``extern`` and set up other required linkages. .. warning:: **Warning**: Some platforms do not allow the use of the underscore character (_) as the first character of an exported symbol.