From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.9]:48014 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750703AbcEHJ3S (ORCPT ); Sun, 8 May 2016 05:29:18 -0400 Date: Sun, 8 May 2016 02:29:14 -0700 From: Christoph Hellwig To: "Michael Kerrisk (man-pages)" Cc: Christoph Hellwig , Christoph Hellwig , Alexander Viro , Jens Axboe , Milosz Tanski , "linux-fsdevel@vger.kernel.org" , linux-block@vger.kernel.org, Linux API Subject: Re: [PATCH 2/6] vfs: vfs: Define new syscalls preadv2,pwritev2 Message-ID: <20160508092914.GA30173@infradead.org> References: <1457017443-17662-1-git-send-email-hch@lst.de> <1457017443-17662-3-git-send-email-hch@lst.de> <56E1B9A8.3070904@gmail.com> <20160311095357.GA29350@lst.de> <5714E676.4090007@gmail.com> <20160425084715.GA29255@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org On Mon, Apr 25, 2016 at 07:35:36PM +0200, Michael Kerrisk (man-pages) wrote: > > I'd rather update the man page - EOPNOTSUPP is a much more descriptive > > error code for this case. I'll send you a patch. > > Unless I'm misunderstanding something here, you're proposing something > very inconsistent. The standard error for unknown flag bits is EINVAL. > This is so for dozens of systems calls (check the man pages; you might > find a rare exception, but that's the point, they are exceptions). It > seems to me here that it's really the implementation that needs > fixing, not the man page! For new filesystem calls we try to use EOPNOTSUPP as much as possible, e.g. fallocate.