From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-patches-return-108518-listarch-gdb-patches=sources.redhat.com@sourceware.org>
Received: (qmail 13234 invoked by alias); 18 Dec 2013 20:01:26 -0000
Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <gdb-patches.sourceware.org>
List-Subscribe: <mailto:gdb-patches-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/gdb-patches/>
List-Post: <mailto:gdb-patches@sourceware.org>
List-Help: <mailto:gdb-patches-help@sourceware.org>, <http://sourceware.org/ml/#faqs>
Sender: gdb-patches-owner@sourceware.org
Received: (qmail 13222 invoked by uid 89); 18 Dec 2013 20:01:25 -0000
Authentication-Results: sourceware.org; auth=none
X-Virus-Found: No
X-Spam-SWARE-Status: No, score=-3.0 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,SPF_SOFTFAIL autolearn=no version=3.3.2
X-HELO: mtaout23.012.net.il
Received: from mtaout23.012.net.il (HELO mtaout23.012.net.il) (80.179.55.175) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 18 Dec 2013 20:01:24 +0000
Received: from conversion-daemon.a-mtaout23.012.net.il by a-mtaout23.012.net.il (HyperSendmail v2007.08) id <0MY000100Q4XBY00@a-mtaout23.012.net.il> for gdb-patches@sourceware.org; Wed, 18 Dec 2013 22:01:21 +0200 (IST)
Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout23.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0MY000178QA95JA0@a-mtaout23.012.net.il> for gdb-patches@sourceware.org; Wed, 18 Dec 2013 22:01:21 +0200 (IST)
Date: Wed, 18 Dec 2013 20:01:00 -0000
From: Eli Zaretskii <eliz@gnu.org>
Subject: Re: [RFA] Fix cygwin compilation failure due to nameless LOAD_DLL_DEBUG_EVENT causes ntdll.dll to be missing
In-reply-to: <20131218191757.GC30010@calimero.vinschen.de>
To: gdb-patches@sourceware.org
Reply-to: Eli Zaretskii <eliz@gnu.org>
Message-id: <83y53iapy6.fsf@gnu.org>
References: <52ab8d0e.8aa2420a.30ff.ffffd8f1SMTPIN_ADDED_BROKEN@mx.google.com> <52AF3493.9090708@redhat.com> <20131218112045.GQ30010@calimero.vinschen.de> <83bo0ecgdw.fsf@gnu.org> <20131218160707.GV30010@calimero.vinschen.de> <834n66ccs9.fsf@gnu.org> <20131218171819.GY30010@calimero.vinschen.de> <831u1acblu.fsf@gnu.org> <20131218173155.GA30010@calimero.vinschen.de> <83zjnyaupt.fsf@gnu.org> <20131218191757.GC30010@calimero.vinschen.de>
X-IsSubscribed: yes
X-SW-Source: 2013-12/txt/msg00722.txt.bz2

> Date: Wed, 18 Dec 2013 20:17:57 +0100
> From: Corinna Vinschen <vinschen@redhat.com>
> 
> > > I don't know, but I doubt it.  The filenames in case of calling the
> > > _wfopen functions are probably sent directly to the underlying WIn32
> > > functions.
> > 
> > I don't think they can do that, because it would mean that relative
> > file names, "../foo", etc. are forbidden for _wfopen.  The CRT
> > functions must go through file-name normalization, so unless they
> > detect \\?\ file names up front and refrain from any processing, the
> > long file names will not work, because the normalization routines are
> > where these limitations live, AFAIK.
> 
> There's a lot of theory here.  Did you actually *try* it?

No.  Who can afford to try everything, unless they are paying you to
do that?

> I just did:
> 
> ===========================================
> #include <stdio.h>
> #include <errno.h>
> 
> int main(void)
> {
>   FILE *fp;
> 
>   fp = _wfopen (L"\\\\?\\C:\\Windows\\System32\\ntdll.dll", L"r");
>   if (!fp)
>     printf ("_wfopen w/ long pathname fails, errno = %d\n", errno);
>   else
>     {
>       printf ("_wfopen w/ long pathname works\n");
>       fclose(fp);
>     }
>    return 0;
> }
> ===========================================

Thanks, that's good to know.  But that's just one CRT function.  There
are a gazillion of them, and I'm quite sure some use MAX_PATH of 260
internally.  Just grep the sources of the CRT functions.