"Test case 'csv' produces incorrect result on OpenBSD"
  mmapped pages were not being invalidated when writes occurred to the
  file vi a fd i/o operation. 
  Force explicit invalidation and not rely on implicit invalidation.


sql/examples/ha_tina.cc:
  Bug#15669
    Make sure to invalidate in memory pages when the file has been 
    altered by fd i/o.
    This is important to some operating systems, such as OpenBSD.