From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Greear Subject: Re: RFC: Allow 'ip' to run in daemon mode? Date: Thu, 01 Jul 2010 08:41:45 -0700 Message-ID: <4C2CB739.3020001@candelatech.com> References: <4C2A1291.7000203@candelatech.com> <20100701070753.GA15216@verge.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: NetDev , Stephen Hemminger To: Simon Horman Return-path: Received: from mail.candelatech.com ([208.74.158.172]:54368 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756589Ab0GAPl7 (ORCPT ); Thu, 1 Jul 2010 11:41:59 -0400 In-Reply-To: <20100701070753.GA15216@verge.net.au> Sender: netdev-owner@vger.kernel.org List-ID: On 07/01/2010 12:07 AM, Simon Horman wrote: > On Tue, Jun 29, 2010 at 08:34:41AM -0700, Ben Greear wrote: >> I'm considering modifying 'ip' to be able to run in daemon >> mode so that I can do lots of IP commands without having to >> pay the startup cost of iproute. >> >> The -batch option almost works, but it's hard to programatically >> figure out failure codes. >> >> I'm thinking about making these changes: >> >> 1) Move all of the error printing code into common methods (basically, >> wrap printf). In daemon mode this text can be sent back to the >> calling process, and in normal mode, it will be printed to stdout/stderr >> as it is currently. >> >> 2) Remove all or most calls to 'exit' and instead return error codes >> to the calling logic. >> >> 3) Add ability to listen on a unix socket for commands, basically treat >> them just like batch commands, one command per packet. >> >> 4) Return well formatted error code and text response to calling process >> over the unix socket, maybe something like: >> >> RV: [errno or equiv, zero for success]\n >> CMD: [ command string this relates to ]\n >> [ Optional free form text ] >> >> >> Does something like this have any chance of upstream inclusion? > > Hi Ben, > > can't you achieve as much by omitting 3) and using stdio (cleanly)? > Or in other words, fix batch mode rather than adding another mode. > Or are you worried about backwards-compatibility? I think the most of the work will be in steps 1 and 2. Adding a listening socket and dealing with that is probably 50-100 lines of code. I'd be happy to attempt steps 1, 2, and possibly 4 for standard iproute2. If the unix socket thing still isn't wanted, it would be relatively easy for me to carry a patch to enable it in my own code. I think a lot of folks are scraping the output of 'ip', so backwards compat of the error messages is a concern. Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com