From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Robert P. J. Day" Subject: Re: is "volatile" the cause of ifconfig flags not matching sysfs flags? Date: Thu, 23 Aug 2018 07:50:38 -0400 (EDT) Message-ID: References: <20180822155322.335bd34c@xeon-e3> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Cc: Linux kernel netdev mailing list To: Stephen Hemminger Return-path: Received: from cpanel4.indieserve.net ([199.212.143.9]:60614 "EHLO cpanel4.indieserve.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728665AbeHWPWW (ORCPT ); Thu, 23 Aug 2018 11:22:22 -0400 In-Reply-To: <20180822155322.335bd34c@xeon-e3> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 22 Aug 2018, Stephen Hemminger wrote: > On Wed, 22 Aug 2018 18:32:36 -0400 (EDT) > "Robert P. J. Day" wrote: > > > almost certainly another dumb question, but i was poking around the > > sysfs, particularly /sys/class/net//*, to familiarize myself > > with what i can glean (or set) re interfaces under /sys, and i noticed > > "flags", but what i get there doesn't match what i get by running > > ifconfig. > > > > specifically, if i list the flags for my wireless interface under > > /sys: > > > > $ cat flags > > 0x1003 > > $ > > > > but with ifconfig: > > > > $ ifconfig wlp2s0 > > wlp2s0: flags=4163 mtu 1500 > > ^^^^ > > > > do those two "flags" values represent the same set of flags? and > > does the obvious difference have to do with some of those flags being > > "volatile" as dewscribed in include/uapi/linux/if.h? or am i just > > totally misreading this? > > > > rday > > > > sysfs reports netdevice->if_flags where as ifconfig is getting hex > value from SIOCGIFFLAGS which does: > dev_get_flags(dev) > > The value in sysfs is more intended for internal debugging, where > all the normal userspace API's return a more limited set of > historical values. so the history aside, those values ultimately represent the same flags? rday -- ======================================================================== Robert P. J. Day Ottawa, Ontario, CANADA http://crashcourse.ca/dokuwiki Twitter: http://twitter.com/rpjday LinkedIn: http://ca.linkedin.com/in/rpjday ========================================================================