Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753985Ab1DSInl (ORCPT ); Tue, 19 Apr 2011 04:43:41 -0400 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:36694 "EHLO www.etchedpixels.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753318Ab1DSInk (ORCPT ); Tue, 19 Apr 2011 04:43:40 -0400 Date: Tue, 19 Apr 2011 09:44:36 +0100 From: Alan Cox To: Alexander Holler Cc: Mike Frysinger , linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/1] Implement /dev/byte (a generic byte source similiar to /dev/zero) Message-ID: <20110419094436.0b667410@lxorguk.ukuu.org.uk> In-Reply-To: <4DAD48FC.5040003@ahsoftware.de> References: <1303126676-3456-1-git-send-email-holler@ahsoftware.de> <4DAD48FC.5040003@ahsoftware.de> X-Mailer: Claws Mail 3.7.8 (GTK+ 2.22.0; x86_64-redhat-linux-gnu) Face: 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 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1240 Lines: 26 > As for /dev/zero there are many other possible reasons to use such a > device, besides filling something with a value. For me it's as > reasonable as dev/zero, just that it offers a bit more flexibility and > provides another, at least for me useful, default value. Maybe > /dev/nzero would have been a good name too. ;) /dev/zero exists not to put \0's into files as such but because it is very useful to be able to map the zero page (a read only, or copy-on-write blank page) into programs. The mmap is the reason it is there. > But I don't really care about inclusion into the kernel, it's just > something I had lying around (and needed only marginally work to > finalize as a proper patch) and I thought someone else could find it > usefull and I should share that here. Implementationwise I think I would have gone for allocating a new device and range of 256 minors - that would avoid the funky stuff setting what it fills with as you'd just fill with the minor number. Alan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/