From owner-svn-src-head@freebsd.org  Sun Aug 28 00:38:21 2016
Return-Path: <owner-svn-src-head@freebsd.org>
Delivered-To: svn-src-head@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 2A8BFA940E4
 for <svn-src-head@mailman.ysv.freebsd.org>;
 Sun, 28 Aug 2016 00:38:21 +0000 (UTC)
 (envelope-from mailing-machine@vniz.net)
Received: from mail-lf0-f53.google.com (mail-lf0-f53.google.com
 [209.85.215.53])
 (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits))
 (Client CN "smtp.gmail.com",
 Issuer "Google Internet Authority G2" (verified OK))
 by mx1.freebsd.org (Postfix) with ESMTPS id A708FF56
 for <svn-src-head@freebsd.org>; Sun, 28 Aug 2016 00:38:20 +0000 (UTC)
 (envelope-from mailing-machine@vniz.net)
Received: by mail-lf0-f53.google.com with SMTP id f93so79299395lfi.2
 for <svn-src-head@freebsd.org>; Sat, 27 Aug 2016 17:38:20 -0700 (PDT)
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20130820;
 h=x-gm-message-state:subject:to:references:from:message-id:date
 :user-agent:mime-version:in-reply-to:content-transfer-encoding;
 bh=CqzY24gTXCDAhois49WeRcC2izgSSxhhQlJS35mdWlY=;
 b=VMMjX5uEjwDDgNr4n1Vo00L2b6ye0K5/aBpBcedkLPHgclQfHhpfXRDTwC9FTISmv2
 aPs7lSVpoE9Q2enJwB9/eEoA4y0/hDuDd/Ez8QPFX+5altNKK0jEqX3pH+iF6fQ7CJi7
 cK2IXHC3rktOwhCkFlx/6nP1AuXu+HYl5AskgGwN8JS253SLKbhF8kCLex8RSJpFz5hf
 RevrBt8WK2FNwweFzzjFkvC4C2PBzTRy782tRY4ovinQH9bO9psZCNWbqYb8y8oJ8pRs
 F+mSJRb8uXJIxA9D/00tVW4kGFlQJVyrz23eI2pC79vAP+3NsrLYg77lR4arwKUCXBQG
 nCMQ==
X-Gm-Message-State: AE9vXwPlhmlq35y5MQRD7u0wF710xKhev6k1h1OtC//RckYrhE7jCgd7SMfkkPFS+PVkyQ==
X-Received: by 10.25.150.208 with SMTP id y199mr45608lfd.92.1472344692318;
 Sat, 27 Aug 2016 17:38:12 -0700 (PDT)
Received: from [192.168.1.2] ([89.169.173.68])
 by smtp.gmail.com with ESMTPSA id e123sm5282761lfg.16.2016.08.27.17.38.11
 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
 Sat, 27 Aug 2016 17:38:11 -0700 (PDT)
Subject: Re: svn commit: r304928 - in head/lib/libc: amd64/sys i386/sys sys
To: Konstantin Belousov <kib@FreeBSD.org>, src-committers@freebsd.org,
 svn-src-all@freebsd.org, svn-src-head@freebsd.org
References: <201608272303.u7RN3N0D078505@repo.freebsd.org>
From: Andrey Chernov <ache@freebsd.org>
Message-ID: <9bcf10db-de3f-33ce-e418-03ce3283ac90@freebsd.org>
Date: Sun, 28 Aug 2016 03:38:10 +0300
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101
 Thunderbird/45.2.0
MIME-Version: 1.0
In-Reply-To: <201608272303.u7RN3N0D078505@repo.freebsd.org>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
 <svn-src-head.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head/>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 28 Aug 2016 00:38:21 -0000

On 28.08.2016 2:03, Konstantin Belousov wrote:
>   Since ptrace(2) syscall can return -1 for non-error situations, libc
>   wrappers set errno to 0 before performing the syscall, as the service
>   to the caller.

Both C99 and POSIX directly prohibits any standard function to set errno
to 0. ptrace() should either choose other errno to indicate non-error
situation or change return -1 to something else.