Cygwin supports the O_PATH flag starting with release 3.0.0, but it is buggy 
until release 3.0.8.  (Opening a FIFO with O_PATH causes a hang.)  The attached 
patches work around this problem.  The first patch (which still has a bug number 
that needs to be filled in) uses incorrect indentation for legibility.  The 
second patch fixes the indentation.

Ken