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From: "G.B." <bauhaus@futureapps.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Exclusive file access
Date: Thu, 27 Aug 2015 16:48:55 +0200
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Date: 2015-08-27T16:48:55+02:00
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On 27.08.15 15:52, ahlan@marriott.org wrote:
> Dear All,
>
> Obviously I'm misunderstanding something here.
>
> I thought that if two processes tried to open the same file for write access then the second process would get an exception.
>
> I have a simple example which when compiled using GnatPro 7.3.1 and run under 32-bit Windows XP demonstrates that this is not so.
>
> Which then begs the question on how to detect if the file is in use and abort if it is.
> This should be simple but obviously too complex for my tiny brain.
> Does anyone know how to do this from Ada (without resorting to the OS directly)?

GNAT RM, section "11.10 Shared Files" addresses this for
GNAT GPL; GNAT Pro should have a similar/the same section.

(The manual is installed with the compiler, e.g. in the
share/doc/gnat subdirectory.)