From owner-cvs-all  Tue Mar 27 23:45: 3 2001
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Date: Wed, 28 Mar 2001 08:44:57 +0100
From: David Malone <dwmalone@maths.tcd.ie>
To: "Andrey A. Chernov" <ache@FreeBSD.org>
Cc: cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org
Subject: Re: cvs commit: src/usr.bin/tail forward.c
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On Tue, Mar 27, 2001 at 03:24:26PM -0800, Andrey A. Chernov wrote:

>   Restore part of my fix spammed in v1.23:

I actually discussed this with Ian before committing, so spammed
is a bit strong. ;-)

>   fseeko(file_size, SEEK_SET) -> fseek(0L, SEEK_END)
>   1) File may grows between operations, so fseeko to file_size may miss
>   2) 0L, SEEK_END is the same code using in tail in all other places

The problem is that you only want to seek to the end of the data
you have already displayed, not to the end of the file.  Otherwise
if you are using "tail -f" and the file grows between the original
stat and the fseek you will not print the data in between.

Can you confirm that fseeko(file_size, SEEK_SET) is actually correct?

	David.

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