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From: kilgallen@eisner.decus.org (Larry Kilgallen)
Subject: Re: Conceptual Ada Problems
Date: 1996/09/29
Message-ID: <1996Sep29.194017.1@eisner>#1/1
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 <Pine.GSO.3.93.960929230049.29986A-100000@firefly.sd.monash.edu.au>
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Date: 1996-09-29T00:00:00+00:00
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In article <Pine.GSO.3.93.960929230049.29986A-100000@firefly.sd.monash.edu.au>, Vasilios Tourloupis <vasilios@insect.sd.monash.edu.au> writes:

> * Is there some way of storing/retrieving records in an Ada.Direct_IO
>   file using key fields of records rather than their location in the file?

That sounds like an indexed file system, and Ada standards have not
included the specification of such.  DEC Ada for VMS includes packages
to access the RMS indexed file system which is already present on that
operating system.  I would presume that in other environments which
have an indexed file system Ada vendors likewise supply such packages
so all customers do not have to reinvent the wheel.

One could of course write a portable indexed file system in Ada,
but considering the degree of system-specific optimization generally
provided for indexed file systems, the performance of a portable
system would likely be unsatisfactory.

Larry Kilgallen