Re: [PATCH 4/4] coccicheck: add indexing enhancement options

From: "Luis R. Rodriguez" <mcgrof@kernel.org>
To: Julia Lawall <julia.lawall@lip6.fr>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>,
	Gilles Muller <Gilles.Muller@lip6.fr>,
	nicolas.palix@imag.fr, mmarek@suse.com,
	linux-kernel@vger.kernel.org, cocci@systeme.lip6.fr
Subject: Re: [PATCH 4/4] coccicheck: add indexing enhancement options
Date: Tue, 14 Jun 2016 23:10:43 +0200	[thread overview]
Message-ID: <20160614211043.GF11948@wotan.suse.de> (raw)
In-Reply-To: <alpine.DEB.2.02.1606142246030.2057@localhost6.localdomain6>

On Tue, Jun 14, 2016 at 10:47:32PM +0200, Julia Lawall wrote:
> 
> 
> On Tue, 14 Jun 2016, Luis R. Rodriguez wrote:
> 
> > On Tue, Jun 14, 2016 at 07:22:03AM +0200, Julia Lawall wrote:
> > > 
> > > 
> > > On Mon, 13 Jun 2016, Luis R. Rodriguez wrote:
> > > 
> > > > On Mon, Jun 13, 2016 at 09:50:15PM +0200, Julia Lawall wrote:
> > > > > 
> > > > > 
> > > > > On Mon, 13 Jun 2016, Luis R. Rodriguez wrote:
> > > > > > 
> > > > > > I'll redirect stderr to stdout by default when parmap support is used then.
> > > > > 
> > > > > Usually I put them in different files.
> > > > 
> > > > We can do that as well but I would only want to deal with parmap support 
> > > > case. Any preference? How about .coccicheck.stderr.$PID where PID would 
> > > > be the PID of the shell script?
> > > 
> > > I don't understand the connection with parmap.
> > 
> > When parmap support is not available the cocciscript will currently
> > disregard stderr, output is provided as it comes to stdout from each
> > thread I guess.
> 
> Deepa's recent patch to coccicheck made apparent that Coccicheck uses 
> --very-quiet, so there is standard error.

OK I'm disegarding the redirect for non-parmap for now but we'd have to
determine if we want to append or add one per PID... I rather leave that
stuff as-is and encourage folks to upgrade coccinelle.

> > > Originally our use of parmap made output files based on pids.  Maybe this 
> > > is the default for parmap.  I found this completely unusable.  I guess one 
> > > could look at the dates to see which file is the most recent one, but it 
> > > seems tedious.  If you are putting the standard output in x.out, then put 
> > > the standard error in x.err.
> > 
> > I'll use ${DIR}/coccicheck.$$.err for stderr.
> 
> What is ${DIR}? and what is $$?

When you run scripts/coccicheck we take the absolute directory
of it and then go down one level of directory, so in this case it
would be the base directory of the Linux kernel.

$$ is the PID of the bash script.

  Luis