From owner-freebsd-hackers  Fri Sep 21 21:25:47 2001
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Date: Fri, 21 Sep 2001 21:25:30 -0700
From: John Merryweather Cooper <john_m_cooper@yahoo.com>
To: Mario Sergio Fujikawa Ferreira <lioux@uol.com.br>
Cc: freebsd-hackers@freebsd.org
Subject: Re: bug in shell `` expansion code?
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References: <20010922011302.A44620@exxodus.fedaykin.here>
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In-Reply-To: <20010922011302.A44620@exxodus.fedaykin.here>; from lioux@uol.com.br on Fri, Sep 21, 2001 at 21:13:02 -0700
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On 2001.09.21 21:13 Mario Sergio Fujikawa Ferreira wrote:
> Hi,
> 
> 	While working on a make .mk code, I and Chris Wasser (TDF
> on IRC) came across an interesting behavior:
> 
> sh -c 'TDF="echo a && echo b";for i in `${TDF}`; do echo "i:$i"; done'
> 
> This should return:
> 
> i:a
> i:b
> 
> instead, it returns:
> 
> i:a
> i:&&
> i:echo
> i:b
> 
> 	If this is not a bug, how do we get it working?
> 
> 	Regards,
> 
> -- 
> Mario S F Ferreira - UnB - Brazil - "I guess this is a signature."
> lioux at ( freebsd dot org | linf dot unb dot br )
> flames to beloved devnull@someotherworldbeloworabove.org
> feature, n: a documented bug | bug, n: an undocumented feature
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
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> 

This works:

$ sh -c 'TDF="echo a && echo b";for i in `eval ${TDF}`; do echo "i:$i";
done'

I believe eval is necessary in this context, otherwise the && is not
"evaluated."  I checked, and the same behavior holds if sh is changed to
bash.

-- 
jmc

MacroHard -- the perfection of form over
             substance, marketing over
             performance, and greed over
             design . . .

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