Return-path: Received: from xc.sipsolutions.net ([83.246.72.84]:58656 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754262AbZIWHVw (ORCPT ); Wed, 23 Sep 2009 03:21:52 -0400 Subject: Re: [RFC] nl80211: introduce NL80211_ATTR_SCAN_EXPIRE From: Johannes Berg To: Holger Schurig Cc: Dan Williams , "linux-wireless@vger.kernel.org" , John W Linville In-Reply-To: <200909230912.57417.hs4233@mail.mn-solutions.de> References: <200909181849.22302.hs4233@mail.mn-solutions.de> <200909210946.19675.hs4233@mail.mn-solutions.de> <1253662172.2510.60.camel@localhost.localdomain> <200909230912.57417.hs4233@mail.mn-solutions.de> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-WrR2JOkOPoZPXaSNOYwT" Date: Wed, 23 Sep 2009 09:21:45 +0200 Message-Id: <1253690505.4458.29.camel@johannes.local> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: --=-WrR2JOkOPoZPXaSNOYwT Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2009-09-23 at 09:12 +0200, Holger Schurig wrote: > There's just one case: if there is no BSS in the scan list. > Then any app doing a "get scan results" call wouldn't know > if the last scan is ages ago or if there is really no AP > in the vincinity, doing an immediate re-scan. This can be > harmful for battery-driven devices. So maybe a timestamp > "last scan was at timestamp XXX" besides the individual > BSS timestamps would be helpful here. >=20 > This way apps can synchronize themselfes and, even if > different apps do scanning, they can say "We don't scan > more often than every N seconds". You can monitor nl80211 events for scan completion already, so this isn't really an issue. In fact, adding a "last scan" thing would not be a good idea since the scan might have been different, only contained a subset of channels, etc. johannes --=-WrR2JOkOPoZPXaSNOYwT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- iQIcBAABAgAGBQJKucyFAAoJEODzc/N7+QmaragQALR5lFDklG1ss5ACb6MXsOly EiMmeLAjP4sQPs+lv6fkIYg6CakUFenRwiVPeXV1HDpze9z9EOw59DBtMoZ7MnI2 yXJ9gKvjt9cbFLeeAzcTZhzzxlntrADJ8yUF9YRBiZerWA1wm+wzdl2ker1f049n 8Pvvl6oGH34RabClyS/8u5tib2JhWDSPZXyf9ZlxJ7KYt9rX0O1RvfFlAl6JxPrH S6zhTFMUzzA/4x3llAybj8mJLZ+uukdsNduxVdNcSaV27+iNX15weMkIckzWk3q/ CtX2DUkquc+Sc0TL5q/RLwtLc48rja57gc4+BA52l4G5XuVo2H2//wp84qVKNkPX gH0Tt3vBkowBrmvbwrlMLMWV9wlFOL1PRVTnA+k/IUMNgCnUyzM7P7h9zomGyQth t1Y8a/sZXiZ4CzMbuKvsvmzgewbob1cty2MdcfTjz56O4F8RLGrwOjQzV+TFnLBG LCx+CsfYTYuEchBhp3oZ8TjCqRey7nT1iNEQ6kPvICRXVGNn7L2VTkxsltQrtTAL D5zaNYE20LZ0+M3OnRPnM3Ks6evdoZTyccytDBpYcu27AQ9RhaSDsA3sClZS1qOI tQEUed4yKuzvq7qpID76xVK9GFsdOlCZf2T7F+tzYSH7g1yB8hFG2uxyy8QZUUHQ 31IanHBqyuH9KPvdtn5O =C1ZX -----END PGP SIGNATURE----- --=-WrR2JOkOPoZPXaSNOYwT--