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Date:   Mon, 31 Jul 2023 17:41:36 +0200
From:   Thomas =?utf-8?Q?Wei=C3=9Fschuh?= <thomas@t-8ch.de>
To:     Yuan Tan <tanyuan@tinylab.org>
Cc:     falcon@tinylab.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org, w@1wt.eu
Subject: Re: [PATCH v2 2/2] selftests/nolibc: add testcase for pipe
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On 2023-07-31 20:35:28+0800, Yuan Tan wrote:
> On Mon, 2023-07-31 at 08:10 +0200, Thomas Weißschuh wrote:
> > On 2023-07-31 13:51:00+0800, Yuan Tan wrote:
> > > Add a testcase of pipe that child process sends message to parent
> > > process.
> > 
> > Thinking about it some more:
> > 
> > What's the advantage of going via a child process?
> > The pipe should work the same within the same process.
> > 
> 
> The pipe is commonly used for process communication, and I think as a
> test case it is supposed to cover the most common scenarios.

The testcase is supposed to cover the code of nolibc.
It should be the *minimal* amount of code to be reasonable sure that the
code in nolibc does the correct thing.
If pipe() returns a value that behaves like a pipe I see no reason to
doubt it will also survive fork().

Validating that would mean testing the kernel and not nolibc.
For the kernel there are different testsuites.

Less code means less work for everyone involved, now and in the future.