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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: set_index and and end_of_file with just a stream reference
Date: Sat, 20 Feb 2021 21:41:06 +0000
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Mehdi Saada <00120260a@gmail.com> writes:

> Okay :-)
> what I wanted is:
> I read an acronyme in the stream file, if good I input the adjacent
> record type, otherwise I would advance on the stream until the next
> acronyme with set_index(stream_access, index(stream_access) +
> composite_type_stream_size) and read the next acronyme
> (unbounded_string).
> Now I just input both objects and verify the acronyme.
> But I don't like writing an object that maybe won't be used.

Unless your objects are megabytes in size, I'd strongly suggest you just
read the thing in anyway. It'd stand a chance of working, then you can
benchmark and see whether it needs improvement.

I thought you wanted to manage concurrent access to this stream? in
which case you're going to need to read the tag and the object together,
even if it turns out you don't need the object after all.