Re: [PATCH 2/3] t5615: avoid re-using descriptor 4

From: Stefan Beller <sbeller@google.com>
Date: Oct 19, 2017, 21:46 UTC
Message-ID: <CAGZ79kYTmUnM+fcf222-cvwB3Fg4+J_xy28E7A3AYryx4qDf_w@mail.gmail.com>
In-Reply-To: <20171019210730.sgm4g4tmor2dgjv7@sigill.intra.peff.net>

Show 11 quoted lines

> I also considered trying to bump the "set -x" output descriptor to "9".
> That just moves the problem around, but presumably scripts are less
> likely to go that high. :)
>
> It would also be possible to pick something insanely high, like "999".
> Many shells choke on descriptors higher than 9, but since the issue is
> related to BASH_XTRACEFD, we could make it a bash-only thing. I don't
> know if it's worth the trouble. I hate leaving a subtle "don't use
> descriptor 4 in a subshell or your script will break" hand-grenade like
> this lying around, but we do seem to have only one instance of it over
> the whole test suite.

I would imagine that a higher fd for BASH_XTRACEFD would be less explosive than requiring the tests to skip the low number 4. (It is not *that* low. In e.g. git-submodule.sh we make use of 3 in cmd_foreach, not needing more.)

Thanks, Stefan