From: Jeff King <peff@peff.net>
Date: Mon, 16 Apr 2012 17:42:30 GMT
Subject: Re: [PATCH] t5570: forward git-daemon messages in a different way
Message-ID: <20120416174230.GA19226@sigill.intra.peff.net>
In-Reply-To: <4F8C3E0F.2040300@in.waw.pl>

On Mon, Apr 16, 2012 at 05:43:11PM +0200, Zbigniew Jędrzejewski-Szmek wrote:

> % dash -x test2.sh | wc -l
> + mkfifo fd
> + pid=10738
> + read line
> + yes
> + echo y
> + sleep 1
> + kill 10738
> test2.sh: 12: kill: No such process
> 
> + wait 10738
> + rm -f fd
> ^C
> 
> It hangs at the end until killed with ^C. This seem to happen fairly reliably
> (nineteen times out of twenty or so). This is with dash 0.5.7-3 and 0.5.5.1-7.4
> from debian. With bash test2.sh seems to always run successfully.

Hmm. t5570 seems to pass reliably on dash for me with:

diff --git a/t/lib-git-daemon.sh b/t/lib-git-daemon.sh
index ef2d01f..9f52cb6 100644
--- a/t/lib-git-daemon.sh
+++ b/t/lib-git-daemon.sh
@@ -33,7 +33,7 @@ start_git_daemon() {
 	{
 		read line
 		echo >&4 "$line"
-		cat >&4 &
+		cat >&4 <git_daemon_output &
 
 		# Check expected output
 		if test x"$(expr "$line" : "\[[0-9]*\] \(.*\)")" != x"Ready to rumble"

But the test above does fail. Is it purely luck of the timing that
git-daemon never gets SIGPIPE? I guess the problem is that the
{}-section can finish before "cat <git_daemon_output" has actually
opened the pipe?

I'd just feel better about the solution if we were sure we understood
the exact problem.

-Peff