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Date: Mon, 18 Aug 2003 00:24:35 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: Dan Langille <dan@langille.org>
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cc: freebsd-hackers@freebsd.org
Subject: Re: Is tar doing the right thing here?
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In the last episode (Aug 18), Dan Langille said:
> Why is this message not being suppressed?
> 
> $ tar -czf test.tgz / 2>&1 > /dev/null
> tar: Removing leading `/' from member names

What you did was dup fd1 onto fd2, then redirect fd1 to /dev/null:

        fd1 -> stdout        fd2 -> stderr
2>&1
        fd1 -> stdout        fd2 -> stdout
>/dev/null
        fd1 -> /dev/null     fd2 -> stdout

Swap the two redirects, so you redirect fd1 to /dev/null, then dup it
onto fd2:

        fd1 -> stdout        fd2 -> stderr
>/dev/null
        fd1 -> /dev/null     fd2 -> stdout
2>&1
        fd1 -> /dev/null     fd2 -> /dev/null

-- 
	Dan Nelson
	dnelson@allantgroup.com