From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: [PATCH 3 of 3] [xen-detect] Add arguments to print out only outputs we are interested in Date: Tue, 22 Dec 2009 20:21:14 +0000 Message-ID: References: <04c067941b17bdc679ff.1261500538@phenom.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <04c067941b17bdc679ff.1261500538@phenom.dumpdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Konrad Rzeszutek Wilk , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 22/12/2009 16:48, "Konrad Rzeszutek Wilk" wrote: > # HG changeset patch > # User konrad@phenom.dumpdata.com > # Date 1261498156 18000 > # Node ID 04c067941b17bdc679ffdc2f6c81f8e2f78e9cc5 > # Parent 7bd805a543da685a3dba7b8b0c4e3e7052c863b3 > [xen-detect] Add arguments to print out only outputs we are interested in. > > This is quite usefull in scripts where you can do > if xen-detect -P || modprobe xen- > > And do not have to parse the output - instead you will get > the output only if the condition exists. Er, what? The above shell fragment is affected by the value returned by xen-detect (0 versus non-0), not by whether it prints something! Here is my suggestion: keep your new command-line options, but instead of affecting printing, have them affect the return value. E.g., -P causes return 0 if running PV, else return 1. Further, we can add a -q option to quiesce normal output from xen-detect, to make it quieter for use in shell scripts. E.g, xen-detect -Pq && modprobe some-xen-pv-specific-module What do you think of that? -- Keir