From mboxrd@z Thu Jan  1 00:00:00 1970
From: ishare <june.tune.sea@gmail.com>
Date: Thu, 14 Mar 2013 12:24:21 +0000
Subject: sed questions
Message-Id: <20130314122421.GA4610@debian.localdomain>
List-Id: <linux-sh.vger.kernel.org>
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To: linux-sh@vger.kernel.org

   In this command:

       sed '/^$/d' 1.txt
   
   what is the use of ^ and $ ?
   
   Are they two belonged to shell sematic or exlusive use for sed?  

   thanks!