From owner-freebsd-questions@FreeBSD.ORG  Thu Jan 29 08:40:56 2004
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id C35DD16A4CF
	for <questions@freebsd.org>; Thu, 29 Jan 2004 08:40:56 -0800 (PST)
Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 6BC1843D4C
	for <questions@freebsd.org>; Thu, 29 Jan 2004 08:40:55 -0800 (PST)
	(envelope-from dan@dan.emsphone.com)
Received: (from dan@localhost)
	by dan.emsphone.com (8.12.10/8.12.10) id i0TGetJK022528;
	Thu, 29 Jan 2004 10:40:55 -0600 (CST)
	(envelope-from dan)
Date: Thu, 29 Jan 2004 10:40:54 -0600
From: Dan Nelson <dnelson@allantgroup.com>
To: zhangweiwu@realss.com
Message-ID: <20040129164054.GC31560@dan.emsphone.com>
References: <Law11-F24kd4grUYzTB00027121@hotmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <Law11-F24kd4grUYzTB00027121@hotmail.com>
X-OS: FreeBSD 5.2-CURRENT
X-message-flag: Outlook Error
User-Agent: Mutt/1.5.5.1i
cc: questions@freebsd.org
Subject: Re: use \000 in sed
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>,
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>,
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 29 Jan 2004 16:40:56 -0000

In the last episode (Jan 30), Zhang Weiwu said:
> Dan Nelson wrote:
> >I'm not sure that sed can process \123-style octal characters, since
> >it already uses the \ character for backreferences.  Since you're
> >only replacing one letter, you can use tr:
> >
> >manpath | tr ':' '\000' | xargs -0 ls 
> >
> oh Brilliant, i almost forgot this command!
> 
> But once I need to work with complex replacement, do I have to use
> the two commands together?
> 
> #cmd... | tr .... | sed ...

Maybe.  After reading a bit about xargs, here's an alternate way using
only sed:

manpath | sed -e 's/ /\\ /g' -e 's/:/ /g' | xargs -0 ls

First you escape any spaces in the input, then you replace : with
space.  If you have even weirder pathnames, like ones with quotes or
backslashes in them, you can use this:

sed -e 's/\([^:]\)/\\\1/g' -e 's/:/ /g'

which will backslash-escape everything except colons.

-- 
	Dan Nelson
	dnelson@allantgroup.com