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Date: Fri, 15 Feb 2002 12:17:58 -0600 (CST)
From: Jesse Pollard <pollard@tomcat.admin.navo.hpc.mil>
Message-Id: <200202151817.MAA28366@tomcat.admin.navo.hpc.mil>
To: l.allegrucci@tiscalinet.it, linux-kernel@vger.kernel.org
Subject: Re: Redundant syscalls?
In-Reply-To: <02021517152700.01701@odyssey>
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> 
> 
> I was wondering why do we need fsetxattr(2), fgetxattr(2) etc when we 
> already have setxattr(2), getxattr(2) etc working on file names
> instead of file descriptors.
> truncate(2)/ftruncate(2) is another more traditional example.

Atomic actions.

Consider the case of a file that doesn't exist yet. first you
open it, then perform the fsetxattr. If you use the name, then it becomes
possible to rename the file and substitute a different one before the
setxattr. Now, the open file will be missing the attribute(s).
-------------------------------------------------------------------------
Jesse I Pollard, II
Email: pollard@navo.hpc.mil

Any opinions expressed are solely my own.
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