From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCHv3] gpg-interface: check gpg signature creation status
Date: Tue, 14 Jun 2016 11:13:54 -0700
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Cc: git@vger.kernel.org, Jeff King <peff@peff.net>,
	ZhenTian <loooseleaves@gmail.com>
To: Michael J Gruber <git@drmicha.warpmail.net>
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In-Reply-To: <8e08b63b58302b6e7fe91f0dfb5b476781bfd37d.1465915311.git.git@drmicha.warpmail.net>
	(Michael J. Gruber's message of "Tue, 14 Jun 2016 16:44:18 +0200")
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Michael J Gruber <git@drmicha.warpmail.net> writes:

>  	bottom = signature->len;
> -	len = strbuf_read(signature, gpg.out, 1024);
> +	strbuf_read(signature, gpg.out, 1024);
> +	strbuf_read(&err, gpg.err, 0);

Hmmmm, isn't this asking for a deadlock?  When GPG spews more than
what would fit in a pipe buffer to its standard error (hence gets
blocked), its standard output may not complete, and the we would get
stuck by attempting to read from gpg.out, failing to reach the other
strbuf_read() that would unblock GPG by reading from gpg.err?