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Date: Sun, 28 Aug 2016 03:56:37 +0300
From: Konstantin Belousov <kostikbel@gmail.com>
To: Andrey Chernov <ache@freebsd.org>
Cc: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: Re: svn commit: r304928 - in head/lib/libc: amd64/sys i386/sys sys
Message-ID: <20160828005637.GG83214@kib.kiev.ua>
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On Sun, Aug 28, 2016 at 03:38:10AM +0300, Andrey Chernov wrote:
> 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.
> 
ptrace(2) is not a standard function.
And, we cannot break ABI for the syscall.