To simplify common code, I propose changing the status of realpath() from a Posix-specific API to a globally available API, i.e. adding it to the "Hotspot Porting API".

This would require the addition of a stub routine in os_posix.cpp and a Windows implementation of realpath(), using Windows _fullpath().

Please note that guidelines for doing this appear in src/hotspot/share/runtime/os.hpp