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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: GNAT Modification_Time limitation
Date: Wed, 21 Nov 2018 19:48:39 +0000
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Date: 2018-11-21T19:48:39+00:00
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Lionel Draghi <lionel.draghi@gmail.com> writes:

> And to build the dependency graph, I need to identify which file is an
> input file, and which one is an output (a target).
>
> To do so, I can either:
> 1. make a complex analysis of a detailed strace log file on each file
> operation;
> 2. just ask strace the list of the involved files, and classify those
> file thanks to modification time : if file modification time >
> execution time, then it's an output.

Can't you tell from strace which files were opened for read and which
for write?

I suppose there are some files that are opened read/write; either,
perhaps most usually, in separate parts of the build, or by being
updated in one.

I have one project (tcladashell) which runs a tcl script to generate a C
source, which is compiled, built, and run to generate an Ada package
spec. Which is then used in the rest of the build.