SRA Win32 sync() code

Here is the SRA sync() code for Win32.  As you might know, fsync on
Win32 is _commit, and sync() is _flushall.  However, _flushall only
flushes only _open_ kernel buffers, not dirty buffers that have been
closed.  Therefore, on Win32, during checkpoint, you have to open,
fsync(_commit), close all file that have been modified since the
previous checkpoint.

Not sure how we are going to do this in Win32, but somehow we will have
to record all open files between checkpoints in an area that the
checkpoint process can read during a checkpoint.

Here is the SRA code that records the dirty file and the code that
cycles through the list and fsync's each one.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
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