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From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] Refactor recv_sideband()
Date: Tue, 14 Jun 2016 12:16:17 -0700
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Cc: "Nicolas Pitre" <nico@fluxnic.net>, git@vger.kernel.org,
	"Johannes Sixt" <j6t@kdbg.org>
To: Lukas Fleischer <lfleischer@lfos.de>
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In-Reply-To: <146593150503.20857.6674861809731777501@typhoon.lan> (Lukas
	Fleischer's message of "Tue, 14 Jun 2016 21:11:55 +0200")
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Lukas Fleischer <lfleischer@lfos.de> writes:

> One possible solution is using strbuf and constructing the message as we
> did before. However, that still relies on fprintf() only calling write()
> once per format specifier. While that is probably true for all existing
> implementations, I don't think it is guaranteed by some standard.
> Shouldn't we always use the stderr stream when printing error messages
> instead, especially when we care about thread safety?

Or you can always write(2) to fd=2 and that is safe, too.