PFSYNC (was Re: Record locking)

[Kenneth Brody]

John Esak wrote:
[...]
> All that PFSYNC does (on Windows
> that is...) is force the immediate writing of the directory table.

Actually, under DOS, the system call simply causes the directory entry
to be updated.  (Normally, if you write off the end of a file, the file
size as listed in the directory not not increase until the file is
closed.  If the system crashed before you exited filePro, the file
would not show any of the new records, even though they may have been
written to the disk.  A chkdsk usually recovered most of the records.)

However, under Windows, the API documentation shows that it "flushes
the buffers of the specified file and causes all buffered data to be
written to the file".

However, as you point out later, it has no effect on filePro's locking.

[...]
> Therefore, say in Richard's case, I do not think it is helping in the
> WRITE/NOT-UNLOCKING-THE-RECORD problem.
[...]

-- 

+---------+----------------------------------+-----------------------------+
| Kenneth |     kenbrody at spamcop.net      | "The opinions expressed     |
|    J.   |    http://www.hvcomputer.com     |  herein are not necessarily |
|  Brody  |      http://www.fptech.com       |  those of fP Technologies." |
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