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Date: Tue, 11 Jun 2013 09:10:15 +0200
From: Christoph Kukulies <kuku@kukulies.org>
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To: lconrad@go2france.com
Subject: Re: Bourne shell "if" syntax
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On 10.06.2013 20:53, lconrad@go2france.com wrote:
>
>
> script fragment:
>
> PTR=`dig @some.dns +short +norec -x a.b.c.d`
>
> echo "$PTR"
>
> if  [  "$PTR"  ==  ""  ]  ;  then


Use something like (== is wrong, btw.)

#!/bin/sh

if [ "X$1" = "X" ] ; then
    echo foo
fi


--
Christoph

>
> echo "$PTR" >> /path/to/PTR_absent.txt
>
> fi
>
> ===========
>
> output for an IP:
>
>
> a-b-c-d.domain.net.
> [: a-b-c-d.domain.net.: unexpected operator
>
> thanks
> Len
>
>
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