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From: Arnd Bergmann <arnd@arndb.de>
To: Roland McGrath <roland@redhat.com>
Subject: Re: [BUG] Generic syscalls -- chmod vs. fchmodat
Date: Tue, 25 Jan 2011 19:21:14 +0100
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On Tuesday 25 January 2011 18:45:15 Roland McGrath wrote:
>  I know of no reason to
> think that the current treatment of the empty string was ever intended at
> the creation of the *at interfaces.

I always assumed that this was done so that the *at syscalls can replace
both the ones that take a file descriptor (e.g. fstat) and the ones that
take a pathname (e.g. stat), which is sensible for the non-AT_FDCWD case,
although not documented in the man pages.

Treating the empty string special for AT_FDCWD is rather pointless, but
at least consistent.

	Arnd

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Subject: Re: [BUG] Generic syscalls -- chmod vs. fchmodat
Date: Tue, 25 Jan 2011 19:21:14 +0100
Message-ID: <201101251921.15184.arnd@arndb.de>
References: <AANLkTikhKHnR+7DskxYqWXduX4=tpfgsfL4sNYq+4QDq@mail.gmail.com> <201101251529.24779.arnd@arndb.de> <20110125174515.C1DC2183C19@magilla.sf.frob.com>
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On Tuesday 25 January 2011 18:45:15 Roland McGrath wrote:
>  I know of no reason to
> think that the current treatment of the empty string was ever intended at
> the creation of the *at interfaces.

I always assumed that this was done so that the *at syscalls can replace
both the ones that take a file descriptor (e.g. fstat) and the ones that
take a pathname (e.g. stat), which is sensible for the non-AT_FDCWD case,
although not documented in the man pages.

Treating the empty string special for AT_FDCWD is rather pointless, but
at least consistent.

	Arnd