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Date: Tue, 03 Aug 2010 20:21:56 +0200
From: Gabor Kovesdan <gabor@FreeBSD.org>
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To: poyopoyo@puripuri.plala.or.jp
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Cc: current@FreeBSD.org
Subject: Re: bsdgrep does not work with tail -f | grep combination
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Em 2010.08.03. 19:25, poyopoyo@puripuri.plala.or.jp escreveu:
> Hi,
>
> It seems bsdgrep does not work when piped from tail -f.
> I'm running r210728.
>
> term0$ jot 10>  /tmp/1
> term0$ tail -f /tmp/1 | grep 0
> [no output]
>
> otherterm$ jot 10>>  /tmp/1
> [no output to term0]
>
> =====
>
> with GNU grep:
>
> term0$ tail -f /tmp/1 | gnugrep 0
> 10
> otherterm$ jot 10>>  /tmp/1
> [on term0]
> 10
> 10
>    
I've checked on 8.0 and GNU grep doesn't output anything either for me. 
If you use tail -f, you will enter more lines and end it with EOF, won't 
you? And then BSD grep will process the input and print out matches. I 
don't think it's bad behaviour in itself but if you can explain why you 
think it's bad I'm willing to change it.

Thanks for your comment,

Gabor