From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] usage: try harder to format very long error messages
Date: Tue, 11 Aug 2015 09:34:31 -0700
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References: <20150811161752.GA14829@sigill.intra.peff.net>
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Cc: git@vger.kernel.org
To: Jeff King <peff@peff.net>
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In-Reply-To: <20150811161752.GA14829@sigill.intra.peff.net> (Jeff King's
	message of "Tue, 11 Aug 2015 12:17:53 -0400")
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Jeff King <peff@peff.net> writes:

> We use a fixed-size buffer of 4096 bytes to format die() and
> error() messages. We explicitly avoided using a strbuf or
> other fanciness here, because we want to make sure that we
> report the message even in the face of malloc() failure
> (after all, we might even be dying due to a malloc call).

Yes, that was the rationale behind the "we use a fixed-buffer and
try not to allocate in this codepath", I think.

> As for vwritef, it exists solely to work over write(), _and_ it doesn't
> get the "one-shot" thing right (which is probably OK, as we use it only
> when exec fails). But we could probably teach run-command to fdopen(),
> and get rid of it entirely (in favor of teaching vreportf to take a
> FILE* handle instead of assuming stderr).

Sounds like a plan ;-)

The patch looks very sensible.