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Date: Wed, 01 Aug 2012 16:17:25 +0200
From: Laszlo Nagy <gandalf@shopzeus.com>
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>
> Thanks a lotl, someone that writes on the file while reading might be
> an explanation, the problem is that everyone claims that they are only
> reading the file.
If that is true, then make that file system read only. Soon it will turn 
out who is writing them. ;-)
>
> Apparently this file is generated once and a long time after only read
> by two different tools (in sequence), so this could not be possible
> either in theory.. I'll try to investigate more in this sense since
> it's the only reasonable explation I've found so far.
>
Safe solution would be to develop a system where files go through 
"states" in a predefined order:

* allow programs to write into files with .incomplete extension.
* allow them to rename the file to .complete.
* create a single program that renames .complete files to .gz files 
AFTER making them read-only for everybody else.
* readers should only read .gz file
* .gz files are then guaranteed to be complete.