From: Jeff King <peff@peff.net>
Date: Wed, 28 Jan 2009 04:28:14 GMT
Subject: Re: [PATCH] Windows: Fix intermittent failures of t7701
Message-ID: <20090128042814.GA18216@coredump.intra.peff.net>
In-Reply-To: <alpine.DEB.1.00.0901271740320.3586@pacific.mpi-cbg.de>

On Tue, Jan 27, 2009 at 05:42:03PM +0100, Johannes Schindelin wrote:

> > We want to catch failures of test-chmtime; but since it appears in a 
> > pipe, we cannot access its exit code. Therefore, we at least make sure 
> > that it prints time stamps of all files that are passed on its command 
> > line.
> 
> I use this trick in my valgrind series:
> 
> 	($PROGRAM; echo $? > exit.code) | $OTHER_PROGRAM &&
> 	test 0 = "$(cat exit.code)"

Oh, that's far too readable. How about:

  exec 3>&1
  status=$( ( ($PROGRAM ; echo $? >&4) | $OTHER_PROGRAM >&3) 4>&1 )
  exec 3>&-

But seriously, I think if we are talking about tests, then

  $PROGRAM >output &&
  $OTHER_PROGRAM <output

is very clear to read, and as a bonus makes "output" accessible for
viewing when the test breaks. The downside is that it isn't very
efficient for a large output, but most of our test output is small (and
we don't care that much about efficiency).

Just my shell bikeshedding 2 cents. Feel free to ignore.

-Peff