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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: File manipulations in Ada.Text_IO
Date: 08 Aug 2005 18:25:13 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2005-08-08T18:25:13-04:00
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Jeffrey Carter <spam@spam.com> writes:

> Larry Kilgallen wrote:
> > But such a function for a non-wildcarded filename is always going
> > to be susceptible to a race condition if the next step would be
> > to open the file.  The file might be deleted or created between
> > the test and using the information gained from the test.
> 
> That's true in the general case, and something I've never encountered in
> 30 years of actual SW development, including software that was intended
> to manipulate the same file from different applications running at the
> same time.

How do you know?  ;-)  I mean, if somebody writes code that contains
such a race condition, and their customer trips over it once in a while,
the programmer might never find out about it.

The server process crashes once in a while.  Nobody knows why.  So the
solution is to restart the server by hand.  (Yuck.)

Race conditions, by their very nature, are impossible to detect with any
confidence via testing.

- Bob