Re: Question on File locking

Hi Vinay -

On Mon, 11 Aug 2014 16:58:16 -0400, Vinay Gavankar
<vinaygav@xxxxxxxxx> wrote:

There is only one program that is writing to this file, but is running
concurrently.

What would be a fool-proof way of writing to the file without having to
trap for error on write and looping.

For example, when getting the lowest sequence, I can keep that record
locked, and then write a record with a lower sequence and then unlock the
file.

You could have a record in another file that the program chains to
first, and holds the lock until the entire CHAIN/subtract/WRITE
sequence is done. This serializes the processing so that there may be
multiple instances of the program running simultaneously, but only one
at a time can add a record.

Ken
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