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Date:   Fri, 8 Feb 2019 13:03:21 -0500
From:   Jeff King <peff@peff.net>
To:     "Randall S. Becker" <rsbecker@nexbridge.com>
Cc:     'Junio C Hamano' <gitster@pobox.com>, git@vger.kernel.org,
        'Linux Kernel' <linux-kernel@vger.kernel.org>,
        git-packagers@googlegroups.com
Subject: Re: [Breakage] Git v2.21.0-rc0 - t5318 (NonStop)
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On Fri, Feb 08, 2019 at 12:49:59PM -0500, Randall S. Becker wrote:

> > We did discuss this at the time of the patch, but it seems we already use
> > /dev/zero in a bunch of places:
> > 
> >   https://public-inbox.org/git/xmqqbm57rkg5.fsf@gitster-ct.c.googlers.com/
> > 
> > Were you just skipping the other tests before?
> 
> I did not catch the implications of the review at the time - my bad. We were not intentionally skipping the tests. It looks like some are automatically skipped. t4153 automatically skips (missing TTY), and t5562 fails also but for a different reason (hang - we don't have apache2 to serve up http content).
> 
> Would you object to something like this:
> 
> if [ ! -e /dev/zero ]; then
> 	# use shred or some other mechanism (still trying to figure out a solution)
> else
> 	# existing dd
> fi

That's fine, as long as it's wrapped up in a function in order to keep
the tests readable.

Though I suspect we may be able to just find a solution that works
everywhere, without having two different implementations. If we know we
need $count bytes for dd, we could probably just generate a file with
that many NULs in it.

Other cases don't seem to actually care that they're getting NULs, and
are just redirecting stdin from /dev/zero to get an infinite amount of
input. They could probably use "yes" for that.

-Peff