From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 907CC16256E1 for ; Mon, 30 Jul 2018 17:30:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 012F3204EC for ; Mon, 30 Jul 2018 17:30:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 012F3204EC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ucw.cz Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727357AbeG3TG4 (ORCPT ); Mon, 30 Jul 2018 15:06:56 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:40429 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726782AbeG3TG4 (ORCPT ); Mon, 30 Jul 2018 15:06:56 -0400 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 512) id 7B1F780662; Mon, 30 Jul 2018 19:30:53 +0200 (CEST) Date: Mon, 30 Jul 2018 19:30:53 +0200 From: Pavel Machek To: David Howells Cc: viro@zeniv.linux.org.uk, torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 36/38] vfs: Add a sample program for the new mount API [ver #10] Message-ID: <20180730173052.GA881@amd> References: <20180730143104.GB24051@amd> <20180729113749.GA7333@amd> <153271267980.9458.7640156373438016898.stgit@warthog.procyon.org.uk> <153271292330.9458.14583488053811372222.stgit@warthog.procyon.org.uk> <25489.1532953411@warthog.procyon.org.uk> <21165.1532964795@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="fdj2RfSjLxBAspz7" Content-Disposition: inline In-Reply-To: <21165.1532964795@warthog.procyon.org.uk> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --fdj2RfSjLxBAspz7 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon 2018-07-30 16:33:15, David Howells wrote: > Pavel Machek wrote: >=20 > > Well, I guess errors should have numbers, and catalog explaining what > > error means what. That way userspace can translate, and it is what we > > do with errno. > > > > I believe numbers are best. If you hate numbers, you can still use > > strings, as long as you can enumerate them in docs (but it will be > > strange design). >=20 > Simply returning error numbers is *not* sufficient. The messages need to= be > parameterised. Still userland needs a way to understand the errors. One way is to pass ( "not enough pixie dust (%d too short) on device %s in %s", 123, "foo", "warddrobe" ). But if you pass it as one string, it becomes hard / impossible to parse. (For example if device is named "foo in bar".) Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --fdj2RfSjLxBAspz7 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAltfS0wACgkQMOfwapXb+vIk3wCfX+fZLbNSHOPD56IRl20NWUh9 n30AoLAjzvWAym6Q24Riu+oKZiPB6NUC =i5V3 -----END PGP SIGNATURE----- --fdj2RfSjLxBAspz7--