Instead of using index() macro defined to strchr, use C99 strchr.
Instead of using rindex() macro defined to strrchr, use C99 strrchr.
If you want to try building on a platform that doesn't offer those
two functions, these are available:
define NOT_C99 /* to make some non-C99 code available */
define NEED_INDEX /* to define a macro for index() */
define NEED_RINDX /* to define a macro for rindex() */
rename sys/winnt to sys/windows
move vs (visual studio) folder out of win/win32 and into sys/windows
rename include/ntconf.h to include/windconf.h
rename winnt.c to windsys.c
place visual studio projects into individual subfolders.
This will hopefully resolve GitHub issue #484 as well.
If an old port is resurrected to work with current version code, its files
can be relocated to the appropriate sys or win folder as required.
In the meantime, the burden of upkeep can be avoided for the stuff in the
outdated folder for now.