From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262024AbVGFAcQ (ORCPT ); Tue, 5 Jul 2005 20:32:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262023AbVGFAcP (ORCPT ); Tue, 5 Jul 2005 20:32:15 -0400 Received: from rwcrmhc14.comcast.net ([216.148.227.89]:21222 "EHLO rwcrmhc12.comcast.net") by vger.kernel.org with ESMTP id S262024AbVGFAbu (ORCPT ); Tue, 5 Jul 2005 20:31:50 -0400 Message-ID: <42CB2677.8060409@namesys.com> Date: Tue, 05 Jul 2005 17:31:51 -0700 From: Hans Reiser User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20041217 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Jeremy Maitin-Shepard CC: David Masover , linux-kernel@vger.kernel.org Subject: Re: reiser4 plugins References: <200507042032.j64KWiY9009684@laptop11.inf.utfsm.cl> <42CB0A40.3070903@slaphack.com> <877jg4an70.fsf@jbms.ath.cx> <42CB0F22.5030609@slaphack.com> <87pstw979h.fsf@jbms.ath.cx> In-Reply-To: <87pstw979h.fsf@jbms.ath.cx> X-Enigmail-Version: 0.90.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Maitin-Shepard wrote: >Okay, so you are suggesting that file-as-dir would provide the user >interface for enabling the encryption or compression. Alternatively, >though, an ioctl could be used to control compression and encryption. > > > Why is it that /proc does not use an ioctl? Use of metafiles could allow eliminating ioctl(), which most folks I know hate as an interface. Wouldn't it be cleaner if we could find out what ioctl()s are supported by a given file using ls filename/..../ioctl? Excerpt from the ioctl man page, which lacks a list of what features are implemented or how to find out. CONFORMING TO No single standard. Arguments, returns, and semantics of ioctl(2) vary according to the device driver in question (the call is used as a catch-all for operations that don't cleanly fit the Unix stream I/O model). See ioctl_list(2) for a list of many of the known ioctl calls. The ioctl function call appeared in Version 7 AT&T Unix.