GNU bug report logs - #9370
"tail -f -1" should work

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Message #11 received at 9370 <at> debbugs.gnu.org (full text, mbox):

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Eli the Beareded <gnu-bugs <at> panix.com>
Cc: 9370 <at> debbugs.gnu.org
Subject: Re: bug#9370: "tail -f -1" should work
Date: Thu, 25 Aug 2011 11:48:45 -0700

On 08/24/11 23:15, Eli the Beareded wrote:
> On any other system I have used the -NUM option can be used with
> the -f option to specify how many lines of the file as-is to print
> before starting to follow it for updates.

The interaction between -NUM and other options is so complicated
and unportable (different editions of the POSIX standards
disagree!) that GNU 'tail' is fairly conservative about where it
allows -NUM.  It might be nice to add support for your particular usage,
if someone wants to write the code, but it'll require some care to make
sure it doesn't run afoul of existing usage or standard in some other way.

In the meantime I suggest using "tail -f -n NUM", as that's standard
and portable these days.

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