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Date: Mon, 10 Dec 2012 21:18:53 +1100
From: Kevin Easton <kevin@guarana.org>
To: Tristan Wibberley <tristan.wibberley@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: New system call wanted: fdreopen
References: <ka2982$ra3$1@ger.gmane.org>
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Quoting Tristan Wibberley <tristan.wibberley@gmail.com>:

> Why
> ===
>
> A common idiom on Linux is to open a file and keep the fd open so that
> the underlying file can be unlinked from its directory. But if the file
> needs to be read from several different parts of the codebase then due to
> the file descriptor having exactly one read pointer those different parts
> must be synchronised which is a relatively difficult task.

Another alternative is to use pwrite() / pread(), which do not affect the file
pointer.  They're in POSIX.

     - Kevin